bims-cagime 2024-03-31 papers

bims-cagime

Biomed News

on Cancer, aging and metabolism

Issue of 2024–03–31
38 papers selected by
Kıvanç Görgülü, Technical University of Munich

Embracing cancer complexity: Hallmarks of systemic disease.
Stress-induced microautophagy is coordinated with lysosome biogenesis and regulated by PIKfyve.
Treatment of pancreatic cancer in 2022.
Glutamine antagonist DRP-104 suppresses tumor growth and enhances response to checkpoint blockade in KEAP1 mutant lung cancer.
Quality of life endpoints in cancer cachexia clinical trials: Systematic review 3 of the cachexia endpoints series.
BCAA metabolism in pancreatic cancer affects lipid balance by regulating fatty acid import into mitochondria.
Circulating factors in cancer cachexia: recent opportunities for translational research.
How much do we know about the metastatic process?
Phosphatidylserine regulates plasma membrane repair through tetraspanin-enriched macrodomains.
Quantitative and Qualitative Radiological Assessment of Sarcopenia and Cachexia in Cancer Patients: A Systematic Review.
Nucleolar stress caused by arginine-rich peptides triggers a ribosomopathy and accelerates aging in mice.
p53: A tale of complexity and context.
It took a long, long time: Ras and the race to cure cancer.
Spatial proteomics in neurons at single-protein resolution.
Control of cell proliferation by memories of mitosis.
KRAS degradation averts PDAC chemoresistance.
TP53INP2-dependent activation of muscle autophagy ameliorates sarcopenia and promotes healthy aging.
Research autopsy programmes in oncology: shared experience from 14 centres across the world.
Western diet-induced ultrastructural changes in mouse pancreatic acinar cells.
Activation of endogenous retroviruses and induction of viral mimicry by MEK1/2 inhibition in pancreatic cancer.
The pleiotropic functions of reactive oxygen species in cancer.
Tumor-secreted FGF21 acts as an immune suppressor by rewiring cholesterol metabolism of CD8+T cells.
Cachexia-Affected Survival Based on Inflammatory Parameters Compared to Complex Conventional Nutritional Assessments in Patients with Pancreatic Cancer and Other Gastrointestinal Tumors-The CONKO 020 Investigation.
The MUC1-HIF-1α signaling axis regulates pancreatic cancer pathogenesis through polyamine metabolism remodeling.
Inoculation of Pan02 cells produces tumor nodules in mouse pancreas: Characterization of a novel orthotopic pancreatic ductal adenocarcinoma tumor model for interventional studies.
EHMT2 Inactivation in Pancreatic Epithelial Cells Shapes the Transcriptional Landscape and Inflammation Response of the Whole Pancreas.
Acute pancreatitis: pathogenesis and emerging therapies.
Pyrimidines maintain mitochondrial pyruvate oxidation to support de novo lipogenesis.
FixNCut: single-cell genomics through reversible tissue fixation and dissociation.
Humanized mouse models for anti-cancer therapy.
p53 dosage can impede KrasG12D- and KrasQ61R-mediated tumorigenesis.
Adhesion energy controls lipid binding-mediated endocytosis.
Senolytic CAR T cells reverse aging-associated defects in intestinal regeneration and fitness.
Paradoxical activation of oncogenic signaling as a cancer treatment strategy.
Expanding the molecular language of protein liquid-liquid phase separation.
Cancer cell invasion: Caveolae and invadosomes are partners in crime.
Non-invasive measurements of blood glucose levels by time-gating mid-infrared optoacoustic signals.
Molecular Pathology of Pancreatic Cystic Lesions with a Focus on Malignant Progression.

Cell. 2024 Mar 28. pii: S0092-8674(24)00175-2. [Epub ahead of print]187(7): 1589-1616

Embracing cancer complexity: Hallmarks of systemic disease.

Charles Swanton, Elsa Bernard, Chris Abbosh, Fabrice André, Johan Auwerx, Allan Balmain, Dafna Bar-Sagi, René Bernards, Susan Bullman, James DeGregori, Catherine Elliott, Ayelet Erez, Gerard Evan, Mark A Febbraio, Andrés Hidalgo, Mariam Jamal-Hanjani, Johanna A Joyce, Matthew Kaiser, Katja Lamia, Jason W Locasale, Sherene Loi, Ilaria Malanchi, Miriam Merad, Kathryn Musgrave, Ketan J Patel, Sergio Quezada, Jennifer A Wargo, Ashani Weeraratna, Eileen White, Frank Winkler, John N Wood, Karen H Vousden, Douglas Hanahan.

The last 50 years have witnessed extraordinary developments in understanding mechanisms of carcinogenesis, synthesized as the hallmarks of cancer. Despite this logical framework, our understanding of the molecular basis of systemic manifestations and the underlying causes of cancer-related death remains incomplete. Looking forward, elucidating how tumors interact with distant organs and how multifaceted environmental and physiological parameters impinge on tumors and their hosts will be crucial for advances in preventing and more effectively treating human cancers. In this perspective, we discuss complexities of cancer as a systemic disease, including tumor initiation and promotion, tumor micro- and immune macro-environments, aging, metabolism and obesity, cancer cachexia, circadian rhythms, nervous system interactions, tumor-related thrombosis, and the microbiome. Model systems incorporating human genetic variation will be essential to decipher the mechanistic basis of these phenomena and unravel gene-environment interactions, providing a modern synthesis of molecular oncology that is primed to prevent cancers and improve patient quality of life and cancer outcomes.

DOI: https://doi.org/10.1016/j.cell.2024.02.009
Mol Biol Cell. 2024 Mar 27. mbcE23080332

Stress-induced microautophagy is coordinated with lysosome biogenesis and regulated by PIKfyve.

Alison D Klein, Kayla L Petruzzi, Chan Lee, Michael Overholtzer.

Lysosome turnover and biogenesis are induced in response to treatment of cells with agents that cause membrane rupture, but whether other stress conditions engage similar homeostatic mechanisms is not well understood. Recently we described a form of selective turnover of lysosomes that is induced by metabolic stress or by treatment of cells with ionophores or lysosomotropic agents, involving the formation of intraluminal vesicles within intact organelles through microautophagy. Selective turnover involves non-canonical autophagy and the lipidation of LC3 onto lysosomal membranes, as well as the autophagy gene-dependent formation of intraluminal vesicles. Here we find a form of microautophagy induction that requires activity of the lipid kinase PIKfyve and is associated with the nuclear translocation of TFEB, a known mediator of lysosome biogenesis. We show that LC3 undergoes turnover during this process, and that PIKfyve is required for the formation of intraluminal vesicles and LC3 turnover, but not for LC3 lipidation onto lysosomal membranes, demonstrating that microautophagy is regulated by PIKfyve downstream of non-canonical autophagy. We further show that TFEB activation requires non-canonical autophagy but not PIKfyve, distinguishing the regulation of biogenesis from microautophagy occurring in response to agents that induce lysosomal stress. [Media: see text] [Media: see text] [Media: see text] [Media: see text] [Media: see text].

DOI: https://doi.org/10.1091/mbc.E23-08-0332
Camb Prism Precis Med. 2023 ;1 e14

Treatment of pancreatic cancer in 2022.

Raffaella Casolino, Andrew V Biankin.

  Pancreatic ductal adenocarcinoma (PDAC) is usually diagnosed at an advanced, incurable, stage and has an extremely poor prognosis. Systemic chemotherapy represents the standard treatment either in the pre-operative, adjuvant and palliative setting, which is associated with only modest improvement in survival. More recently, advances in cancer genomic sequencing have unravelled the molecular heterogeneity of PDAC and identified small patient subgroups harbouring unique actionable aberrations in BRCA, NTRK, NRG1 and mismatch repair genes paving the way to a more personalised approach for this tumour. However, the evolution of PDAC treatment towards a successful precision approach presents many challenges. In this review, we discuss the current standard treatments of PDAC, from early stage to advanced disease, and we illustrate the opportunities and challenges of precision medicine for this deadly cancer.

Keywords:  cancer; clinical trials; pancreatic cancer; precision medicine; therapeutics; treatment approaches

DOI:  https://doi.org/10.1017/pcm.2023.2
Sci Adv. 2024 Mar 29. 10(13): eadm9859

Glutamine antagonist DRP-104 suppresses tumor growth and enhances response to checkpoint blockade in KEAP1 mutant lung cancer.

Ray Pillai, Sarah E LeBoeuf, Yuan Hao, Connie New, Jenna L E Blum, Ali Rashidfarrokhi, Shih Ming Huang, Christian Bahamon, Warren L Wu, Burcu Karadal-Ferrena, Alberto Herrera, Ellie Ivanova, Michael Cross, Jozef P Bossowski, Hongyu Ding, Makiko Hayashi, Sahith Rajalingam, Triantafyllia Karakousi, Volkan I Sayin, Kamal M Khanna, Kwok-Kin Wong, Robert Wild, Aristotelis Tsirigos, John T Poirier, Charles M Rudin, Shawn M Davidson, Sergei B Koralov, Thales Papagiannakopoulos.

Loss-of-function mutations in KEAP1 frequently occur in lung cancer and are associated with poor prognosis and resistance to standard of care treatment, highlighting the need for the development of targeted therapies. We previously showed that KEAP1 mutant tumors consume glutamine to support the metabolic rewiring associated with NRF2-dependent antioxidant production. Here, using preclinical patient-derived xenograft models and antigenic orthotopic lung cancer models, we show that the glutamine antagonist prodrug DRP-104 impairs the growth of KEAP1 mutant tumors. We find that DRP-104 suppresses KEAP1 mutant tumors by inhibiting glutamine-dependent nucleotide synthesis and promoting antitumor T cell responses. Using multimodal single-cell sequencing and ex vivo functional assays, we demonstrate that DRP-104 reverses T cell exhaustion, decreases Tregs, and enhances the function of CD4 and CD8 T cells, culminating in an improved response to anti-PD1 therapy. Our preclinical findings provide compelling evidence that DRP-104, currently in clinical trials, offers a promising therapeutic approach for treating patients with KEAP1 mutant lung cancer.

DOI: https://doi.org/10.1126/sciadv.adm9859
J Cachexia Sarcopenia Muscle. 2024 Mar 29.

Quality of life endpoints in cancer cachexia clinical trials: Systematic review 3 of the cachexia endpoints series.

Cancer Cachexia Endpoints Working Group

  The use of patient-reported outcomes (PROMs) of quality of life (QOL) is common in cachexia trials. Patients' self-report on health, functioning, wellbeing, and perceptions of care, represent important measures of efficacy. This review describes the frequency, variety, and reporting of QOL endpoints used in cancer cachexia clinical trials. Electronic literature searches were performed in Medline, Embase, and Cochrane (1990-2023). Seven thousand four hundred thirty-five papers were retained for evaluation. Eligibility criteria included QOL as a study endpoint using validated measures, controlled design, adults (>18 years), ≥40 participants randomized, and intervention exceeding 2 weeks. The Covidence software was used for review procedures and data extractions. Four independent authors screened all records for consensus. Papers were screened by titles and abstracts, prior to full-text reading. PRISMA guidance for systematic reviews was followed. The protocol was prospectively registered via PROSPERO (CRD42022276710). Fifty papers focused on QOL. Twenty-four (48%) were double-blind randomized controlled trials. Sample sizes varied considerably (n = 42 to 469). Thirty-nine trials (78%) included multiple cancer types. Twenty-seven trials (54%) featured multimodal interventions with various drugs and dietary supplements, 11 (22%) used nutritional interventions alone and 12 (24%) used a single pharmacological intervention only. The median duration of the interventions was 12 weeks (4-96). The most frequent QOL measure was the EORTC QLQ-C30 (60%), followed by different FACIT questionnaires (34%). QOL was a primary, secondary, or exploratory endpoint in 15, 31 and 4 trials respectively, being the single primary in six. Statistically significant results on one or more QOL items favouring the intervention group were found in 18 trials. Eleven of these used a complete multidimensional measure. Adjustments for multiple testing when using multicomponent QOL measures were not reported. Nine trials (18%) defined a statistically or clinically significant difference for QOL, five with QOL as a primary outcome, and four with QOL as a secondary outcome. Correlation statistics with other study outcomes were rarely performed. PROMs including QOL are important endpoints in cachexia trials. We recommend using well-validated QOL measures, including cachexia-specific items such as weight history, appetite loss, and nutritional intake. Appropriate statistical methods with definitions of clinical significance, adjustment for multiple testing and few co-primary endpoints are encouraged, as is an understanding of how interventions may relate to changes in QOL endpoints. A strategic and scientific-based approach to PROM research in cachexia trials is warranted, to improve the research base in this field and avoid the use of QOL as supplementary measures.

Keywords:  Cachexia; Cancer; Patient‐reported outcomes; Quality of life

DOI:  https://doi.org/10.1002/jcsm.13453
Cancer Metab. 2024 Mar 26. 12(1): 10

BCAA metabolism in pancreatic cancer affects lipid balance by regulating fatty acid import into mitochondria.

Klára Gotvaldová, Jitka Špačková, Jiří Novotný, Kamila Baslarová, Petr Ježek, Lenka Rossmeislová, Jan Gojda, Katarína Smolková.

   BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) has been associated with the host dysmetabolism of branched-chain amino acids (BCAAs), however, the implications for the role of BCAA metabolism in PDAC development or progression are not clear. The mitochondrial catabolism of valine, leucine, and isoleucine is a multistep process leading to the production of short-chain R-CoA species. They can be subsequently exported from mitochondria as short-chain carnitines (SC-CARs), utilized in anabolic pathways, or released from the cells.
METHODS: We examined the specificities of BCAA catabolism and cellular adaptation strategies to BCAA starvation in PDAC cells in vitro. We used metabolomics and lipidomics to quantify major metabolic changes in response to BCAA withdrawal. Using confocal microscopy and flow cytometry we quantified the fluorescence of BODIPY probe and the level of lipid droplets (LDs). We used BODIPY-conjugated palmitate to evaluate transport of fatty acids (FAs) into mitochondria. Also, we have developed a protocol for quantification of SC-CARs, BCAA-derived metabolites.
RESULTS: Using metabolic profiling, we found that BCAA starvation leads to massive triglyceride (TG) synthesis and LD accumulation. This was associated with the suppression of activated FA transport into the mitochondrial matrix. The suppression of FA import into mitochondria was rescued with the inhibitor of the acetyl-CoA carboxylase (ACC) and the activator of AMP kinase (AMPK), which both regulate carnitine palmitoyltransferase 1A (CPT1) activation status.
CONCLUSIONS: Our data suggest that BCAA catabolism is required for the import of long chain carnitines (LC-CARs) into mitochondria, whereas the disruption of this link results in the redirection of activated FAs into TG synthesis and its deposition into LDs. We propose that this mechanism protects cells against mitochondrial overload with LC-CARs and it might be part of the universal reaction to amino acid perturbations during cancer growth, regulating FA handling and storage.

Keywords:  BCAA metabolism; Fatty acid/Transport; Fluorescence microscopy; Lipid droplets; Lipidomics; Mitochondria; Pancreatic cancer; Triglycerides

DOI:  https://doi.org/10.1186/s40170-024-00335-5
Curr Opin Clin Nutr Metab Care. 2024 Mar 27.

Circulating factors in cancer cachexia: recent opportunities for translational research.

Marina de Castro Coêlho, Giovana Parreira de Aquino, Amanda Soares Santos, Marilia Seelaender.

PURPOSE OF REVIEW: To discuss the recent discoveries and limitations of the available literature on emerging circulating biomarkers of cancer cachexia.
RECENT FINDINGS: Studies on circulating factors in cancer cachexia show promising alternatives for diagnosing the syndrome in a minimally invasive manner in the clinic setting, as well as potential targets for cancer cachexia treatment. Factors secreted by the tumor and the adipose tissue, such as extracellular vesicles and soluble proteins, respectively, have been shown to either directly induce wasting in vitro and in vivo or to be altered in the cachectic phenotype. The detection and characterization of circulating cells allows detection of the precachectic stage and the levels of the soluble immune checkpoint protein programmed death ligand-1 (PD-L1) are correlated with the presence of the hallmarks of cancer cachexia.
SUMMARY: Structural, molecular, and metabolic alterations have been observed in various tissues, revealing the occurrence of sustained inter-compartment crosstalk in cachectic patients. Early diagnosis of cancer cachexia becomes crucial to avoid the establishment of refractory cachexia through the implementation of interventions that may attenuate systemic inflammation and muscle loss. More studies on human cancer cachexia are required in order to address the recently discovered cachexia-associated circulating factors' value as biomarkers of the syndrome.

DOI: https://doi.org/10.1097/MCO.0000000000001037
Clin Exp Metastasis. 2024 Mar 23.

How much do we know about the metastatic process?

Carolina Rodriguez-Tirado, Maria Soledad Sosa.

  Cancer cells can leave their primary sites and travel through the circulation to distant sites, where they lodge as disseminated cancer cells (DCCs), even during the early and asymptomatic stages of tumor progression. In experimental models and clinical samples, DCCs can be detected in a non-proliferative state, defined as cellular dormancy. This state can persist for extended periods until DCCs reawaken, usually in response to niche-derived reactivation signals. Therefore, their clinical detection in sites like lymph nodes and bone marrow is linked to poor survival. Current cancer therapy designs are based on the biology of the primary tumor and do not target the biology of the dormant DCC population and thus fail to eradicate the initial or subsequent waves of metastasis. In this brief review, we discuss the current methods for detecting DCCs and highlight new strategies that aim to target DCCs that constitute minimal residual disease to reduce or prevent metastasis formation. Furthermore, we present current evidence on the relevance of DCCs derived from early stages of tumor progression in metastatic disease and describe the animal models available for their study. We also discuss our current understanding of the dissemination mechanisms utilized by genetically less- and more-advanced cancer cells, which include the functional analysis of intermediate or hybrid states of epithelial-mesenchymal transition (EMT). Finally, we raise some intriguing questions regarding the clinical impact of studying the crosstalk between evolutionary waves of DCCs and the initiation of metastatic disease.

Keywords:  Disseminated cancer cells; Dormancy; EMT; Early dissemination; Metastasis

DOI:  https://doi.org/10.1007/s10585-023-10248-0
J Cell Biol. 2024 Jun 03. pii: e202307041. [Epub ahead of print]223(6):

Phosphatidylserine regulates plasma membrane repair through tetraspanin-enriched macrodomains.

Yang E Li, Dougall M Norris, Fanqian N Xiao, Elvis Pandzic, Renee M Whan, Sandra Fok, Ming Zhou, Guangwei Du, Yang Liu, Ximing Du, Hongyuan Yang.

The integrity of the plasma membrane is critical to cell function and survival. Cells have developed multiple mechanisms to repair damaged plasma membranes. A key process during plasma membrane repair is to limit the size of the damage, which is facilitated by the presence of tetraspanin-enriched rings surrounding damage sites. Here, we identify phosphatidylserine-enriched rings surrounding damaged sites of the plasma membrane, resembling tetraspanin-enriched rings. Importantly, the formation of both the phosphatidylserine- and tetraspanin-enriched rings requires phosphatidylserine and its transfer proteins ORP5 and ORP9. Interestingly, ORP9, but not ORP5, is recruited to the damage sites, suggesting cells acquire phosphatidylserine from multiple sources upon plasma membrane damage. We further demonstrate that ORP9 contributes to efficient plasma membrane repair. Our results thus unveil a role for phosphatidylserine and its transfer proteins in facilitating the formation of tetraspanin-enriched macrodomains and plasma membrane repair.

DOI: https://doi.org/10.1083/jcb.202307041
J Pers Med. 2024 Feb 24. pii: 243. [Epub ahead of print]14(3):

Quantitative and Qualitative Radiological Assessment of Sarcopenia and Cachexia in Cancer Patients: A Systematic Review.

Sveva Mortellaro, Sonia Triggiani, Federica Mascaretti, Micol Galloni, Ornella Garrone, Gianpaolo Carrafiello, Michele Ghidini.

  Sarcopenia, an extremely common condition in cancer patients, is described as a progressive and generalized musculoskeletal disorder that is associated with an increased likelihood of adverse outcomes, including falls, fractures, physical disability, and mortality. By contrast, cachexia is defined as a syndrome characterized by weight loss with the concomitant loss of muscle and/or fat mass. Cancer cachexia leads to functional impairment, reduced physical performance, and decreased survival, and is often accompanied by cancer progression and reduced response to therapy. The literature states that cancer patients with cachexia or sarcopenia have many more complications than patients without these conditions. The interplay between physiologic sarcopenia and cancer cachexia is, in part, responsible for the complexity of studying wasting disorders in the cancer population, particularly in the geriatric population. For these reasons, a comprehensive assessment of the body composition and physical function of these patients is necessary. There are several modalities adapted to measure skeletal muscle mass, such as dual-energy X-ray absorptiometry (DEXA), bioelectrical impedance analysis (BIA), computed tomography (CT), magnetic resonance imaging (MRI), and ultrasound (US). The gold standard for the measurement of quantitative and qualitative changes in body composition in patients with cancer is the analysis of tissue density using a CT scan. However, this technique remains poorly implemented in clinical practice because of the use of ionizing radiation. Similarly, DEXA, MRI, and US have been proposed, but their use is limited. In this review, we present and compare the imaging techniques that have been developed so far for the nutritional assessment of cancer patients.

Keywords:  BIA; CT scan; DEXA; MRI; cachexia; radiological assessment; sarcopenia

DOI:  https://doi.org/10.3390/jpm14030243
Mol Cell. 2024 Mar 11. pii: S1097-2765(24)00173-4. [Epub ahead of print]

Nucleolar stress caused by arginine-rich peptides triggers a ribosomopathy and accelerates aging in mice.

Oleksandra Sirozh, Anabel Saez-Mas, Bomi Jung, Laura Sanchez-Burgos, Eduardo Zarzuela, Sara Rodrigo-Perez, Ivan Ventoso, Vanesa Lafarga, Oscar Fernandez-Capetillo.

  Nucleolar stress (NS) has been associated with age-related diseases such as cancer or neurodegeneration. To investigate how NS triggers toxicity, we used (PR)n arginine-rich peptides present in some neurodegenerative diseases as inducers of this perturbation. We here reveal that whereas (PR)n expression leads to a decrease in translation, this occurs concomitant with an accumulation of free ribosomal (r) proteins. Conversely, (PR)n-resistant cells have lower rates of r-protein synthesis, and targeting ribosome biogenesis by mTOR inhibition or MYC depletion alleviates (PR)n toxicity in vitro. In mice, systemic expression of (PR)97 drives widespread NS and accelerated aging, which is alleviated by rapamycin. Notably, the generalized accumulation of orphan r-proteins is a common outcome of chemical or genetic perturbations that induce NS. Together, our study presents a general model to explain how NS induces cellular toxicity and provides in vivo evidence supporting a role for NS as a driver of aging in mammals.

Keywords:  aging; nucleolar stress; nucleolus; ribosomal proteins; ribosomopathy

DOI:  https://doi.org/10.1016/j.molcel.2024.02.031
Cell. 2024 Mar 28. pii: S0092-8674(24)00246-0. [Epub ahead of print]187(7): 1569-1573

p53: A tale of complexity and context.

Moshe Oren, Carol Prives.

The story of p53 is illuminating. Despite widespread attention, the tumor-suppressive functions of wild-type p53 or the oncogenic activities of its cancer-associated mutants are still not fully understood, and our discoveries have not yet led to major therapeutic breakthroughs. There is still much to learn about this fascinating protein.

DOI: https://doi.org/10.1016/j.cell.2024.02.043
Cell. 2024 Mar 28. pii: S0092-8674(24)00247-2. [Epub ahead of print]187(7): 1574-1577

It took a long, long time: Ras and the race to cure cancer.

Robert A Weinberg.

Discoveries of the roles of RAS oncogenes in cancer development four decades ago opened the door to proving that tumor development is driven by somatic mutations' altering the genomes of cancer cells. These discoveries led to illusions about the simplicity of cancer pathogenesis and how cancer could be cured.

DOI: https://doi.org/10.1016/j.cell.2024.02.042
Cell. 2024 Mar 28. pii: S0092-8674(24)00248-4. [Epub ahead of print]187(7): 1785-1800.e16

Spatial proteomics in neurons at single-protein resolution.

Eduard M Unterauer, Sayedali Shetab Boushehri, Kristina Jevdokimenko, Luciano A Masullo, Mahipal Ganji, Shama Sograte-Idrissi, Rafal Kowalewski, Sebastian Strauss, Susanne C M Reinhardt, Ana Perovic, Carsten Marr, Felipe Opazo, Eugenio F Fornasiero, Ralf Jungmann.

  To understand biological processes, it is necessary to reveal the molecular heterogeneity of cells by gaining access to the location and interaction of all biomolecules. Significant advances were achieved by super-resolution microscopy, but such methods are still far from reaching the multiplexing capacity of proteomics. Here, we introduce secondary label-based unlimited multiplexed DNA-PAINT (SUM-PAINT), a high-throughput imaging method that is capable of achieving virtually unlimited multiplexing at better than 15 nm resolution. Using SUM-PAINT, we generated 30-plex single-molecule resolved datasets in neurons and adapted omics-inspired analysis for data exploration. This allowed us to reveal the complexity of synaptic heterogeneity, leading to the discovery of a distinct synapse type. We not only provide a resource for researchers, but also an integrated acquisition and analysis workflow for comprehensive spatial proteomics at single-protein resolution.

Keywords:  DNA-PAINT; excitatory synapses; inhibitory synapses; multiplexing; neuron atlas; neuron imaging; proteomics; spatial-omics; super-resolution microscopy; synapse; synapse diversity; synaptic proteins

DOI:  https://doi.org/10.1016/j.cell.2024.02.045
Science. 2024 Mar 29. 383(6690): 1441-1448

Control of cell proliferation by memories of mitosis.

Franz Meitinger, Hazrat Belal, Robert L Davis, Mallory B Martinez, Andrew K Shiau, Karen Oegema, Arshad Desai.

Mitotic duration is tightly constrained, and extended mitosis is characteristic of problematic cells prone to chromosome missegregation and genomic instability. We show here that mitotic extension leads to the formation of p53-binding protein 1 (53BP1)-ubiquitin-specific protease 28 (USP28)-p53 protein complexes that are transmitted to, and stably retained by, daughter cells. Complexes assembled through a Polo-like kinase 1-dependent mechanism during extended mitosis and elicited a p53 response in G1 that prevented the proliferation of the progeny of cells that experienced an approximately threefold extended mitosis or successive less extended mitoses. The ability to monitor mitotic extension was lost in p53-mutant cancers and some p53-wild-type (p53-WT) cancers, consistent with classification of TP53BP1 and USP28 as tumor suppressors. Cancers retaining the ability to monitor mitotic extension exhibited sensitivity to antimitotic agents.

DOI: https://doi.org/10.1126/science.add9528
Nat Cancer. 2024 Mar;5(3): 375-377

KRAS degradation averts PDAC chemoresistance.

Laura Leonhardt, Matthias Hebrok.

DOI: https://doi.org/10.1038/s43018-023-00708-7
Autophagy. 2024 Mar 28. 1-10

TP53INP2-dependent activation of muscle autophagy ameliorates sarcopenia and promotes healthy aging.

David Sebastián, Marc Beltrà, Andrea Irazoki, David Sala, Pilar Aparicio, Cecilia Aris, Esmaeil Alibakhshi, Maria Rubio-Valera, Manuel Palacín, Juan Castellanos, Luis Lores, Antonio Zorzano.

  Sarcopenia is a major contributor to disability in older adults, and thus, it is key to elucidate the mechanisms underlying its development. Increasing evidence suggests that impaired macroautophagy/autophagy contributes to the development of sarcopenia. However, the mechanisms leading to reduced autophagy during aging remain largely unexplored, and whether autophagy activation protects from sarcopenia has not been fully addressed. Here we show that the autophagy regulator TP53INP2/TRP53INP2 is decreased during aging in mouse and human skeletal muscle. Importantly, chronic activation of autophagy by muscle-specific overexpression of TRP53INP2 prevents sarcopenia and the decline of muscle function in mice. Acute re-expression of TRP53INP2 in aged mice also improves muscle atrophy, enhances mitophagy, and reduces ROS production. In humans, high levels of TP53INP2 in muscle are associated with increased muscle strength and healthy aging. Our findings highlight the relevance of an active muscle autophagy in the maintenance of muscle mass and prevention of sarcopenia.Abbreviation: ATG7: autophagy related 7; BMI: body mass index; EIF4EBP1: eukaryotic translation initiation factor 4E binding protein 1; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; ROS: reactive oxygen species; TP53INP2: tumor protein p53 inducible nuclear protein 2; WT: wild type.

Keywords:  Sarcopenia; aging; autophagy; mitophagy; muscle atrophy

DOI:  https://doi.org/10.1080/15548627.2024.2333717
J Pathol. 2024 Mar 29.

Research autopsy programmes in oncology: shared experience from 14 centres across the world.

Tatjana Geukens, Marion Maetens, Jody E Hooper, Steffi Oesterreich, Adrian V Lee, Lori Miller, Jenny M Atkinson, Margaret Rosenzweig, Shannon Puhalla, Heather Thorne, Lisa Devereux, David Bowtell, Sherene Loi, Eliza R Bacon, Kena Ihle, Mihae Song, Lorna Rodriguez-Rodriguez, Alana L Welm, Lisa Gauchay, Rajmohan Murali, Pharto Chanda, Ali Karacay, Cristina Naceur-Lombardelli, Hayley Bridger, Charles Swanton, Mariam Jamal-Hanjani, Lori Kollath, Lawrence True, Colm Morrissey, Meagan Chambers, Arul M Chinnaiyan, Allecia Wilson, Rohit Mehra, Zachery Reichert, Lisa A Carey, Charles M Perou, Erin Kelly, Daichi Maeda, Akiteru Goto, Janina Kulka, Borbála Székely, A Marcell Szasz, Anna-Mária Tőkés, Wouter Van Den Bogaert, Giuseppe Floris, Christine Desmedt.

  While there is a great clinical need to understand the biology of metastatic cancer in order to treat it more effectively, research is hampered by limited sample availability. Research autopsy programmes can crucially advance the field through synchronous, extensive, and high-volume sample collection. However, it remains an underused strategy in translational research. Via an extensive questionnaire, we collected information on the study design, enrolment strategy, study conduct, sample and data management, and challenges and opportunities of research autopsy programmes in oncology worldwide. Fourteen programmes participated in this study. Eight programmes operated 24 h/7 days, resulting in a lower median postmortem interval (time between death and start of the autopsy, 4 h) compared with those operating during working hours (9 h). Most programmes (n = 10) succeeded in collecting all samples within a median of 12 h after death. A large number of tumour sites were sampled during each autopsy (median 15.5 per patient). The median number of samples collected per patient was 58, including different processing methods for tumour samples but also non-tumour tissues and liquid biopsies. Unique biological insights derived from these samples included metastatic progression, treatment resistance, disease heterogeneity, tumour dormancy, interactions with the tumour micro-environment, and tumour representation in liquid biopsies. Tumour patient-derived xenograft (PDX) or organoid (PDO) models were additionally established, allowing for drug discovery and treatment sensitivity assays. Apart from the opportunities and achievements, we also present the challenges related with postmortem sample collections and strategies to overcome them, based on the shared experience of these 14 programmes. Through this work, we hope to increase the transparency of postmortem tissue donation, to encourage and aid the creation of new programmes, and to foster collaborations on these unique sample collections. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Keywords:  liquid biopsy; metastatic cancer; research autopsy; tissue donation; tumour model

DOI:  https://doi.org/10.1002/path.6271
Front Cell Dev Biol. 2024 ;12 1380564

Western diet-induced ultrastructural changes in mouse pancreatic acinar cells.

Saška Lipovšek, Jurij Dolenšek, Barbara Dariš, Ismael Valladolid-Acebes, Tanja Vajs, Gerd Leitinger, Andraž Stožer, Maša Skelin Klemen.

  Mouse models of diet-induced type 2 diabetes mellitus provide powerful tools for studying the structural and physiological changes that are related to the disease progression. In this study, diabetic-like glucose dysregulation was induced in mice by feeding them a western diet, and light and transmission electron microscopy were used to study the ultrastructural changes in the pancreatic acinar cells. Acinar necrosis and vacuolization of the cytoplasm were the most prominent features. Furthermore, we observed intracellular and extracellular accumulation of lipid compounds in the form of lipid droplets, structural enlargement of the cisternae of the rough endoplasmic reticulum (RER), and altered mitochondrial morphology, with mitochondria lacking the typical organization of the inner membrane. Last, autophagic structures, i.e., autophagosomes, autolysosomes, and residual bodies, were abundant within the acinar cells of western diet-fed mice, and the autolysosomes contained lipids and material of varying electron density. While diets inducing obesity and type 2 diabetes are clearly associated with structural changes and dysfunction of the endocrine pancreas, we here demonstrate the strong effect of dietary intervention on the structure of acinar cells in the exocrine part of the organ before detectable changes in plasma amylase activity, which may help us better understand the development of non-alcoholic fatty pancreas disease and its association with endo- and exocrine dysfunction.

Keywords:  acinar cells; autophagy; lipid droplets; mitochondria; necrotic cells; rough endoplasmic reticulum; western diet

DOI:  https://doi.org/10.3389/fcell.2024.1380564
Sci Adv. 2024 Mar 29. 10(13): eadk5386

Activation of endogenous retroviruses and induction of viral mimicry by MEK1/2 inhibition in pancreatic cancer.

Alice Cortesi, Francesco Gandolfi, Fabiana Arco, Pierluigi Di Chiaro, Emanuele Valli, Sara Polletti, Roberta Noberini, Francesco Gualdrini, Sergio Attanasio, Francesca Citron, I-Lin Ho, Rutvi Shah, Er-Yen Yen, Mara Cetty Spinella, Simona Ronzoni, Simona Rodighiero, Nico Mitro, Tiziana Bonaldi, Serena Ghisletti, Silvia Monticelli, Andrea Viale, Giuseppe Riccardo Diaferia, Gioacchino Natoli.

While pancreatic ductal adenocarcinomas (PDACs) are addicted to KRAS-activating mutations, inhibitors of downstream KRAS effectors, such as the MEK1/2 kinase inhibitor trametinib, are devoid of therapeutic effects. However, the extensive rewiring of regulatory circuits driven by the attenuation of the KRAS pathway may induce vulnerabilities of therapeutic relevance. An in-depth molecular analysis of the transcriptional and epigenomic alterations occurring in PDAC cells in the initial hours after MEK1/2 inhibition by trametinib unveiled the induction of endogenous retroviruses (ERVs) escaping epigenetic silencing, leading to the production of double-stranded RNAs and the increased expression of interferon (IFN) genes. We tracked ERV activation to the early induction of the transcription factor ELF3, which extensively bound and activated nonsilenced retroelements and synergized with IRF1 (interferon regulatory factor 1) in the activation of IFNs and IFN-stimulated genes. Trametinib-induced viral mimicry in PDAC may be exploited in the rational design of combination therapies in immuno-oncology.

DOI: https://doi.org/10.1126/sciadv.adk5386
Nat Cancer. 2024 Mar;5(3): 384-399

The pleiotropic functions of reactive oxygen species in cancer.

Katherine Wu, Ahmed Ezat El Zowalaty, Volkan I Sayin, Thales Papagiannakopoulos.

Cellular redox homeostasis is an essential, dynamic process that ensures the balance between reducing and oxidizing reactions within cells and thus has implications across all areas of biology. Changes in levels of reactive oxygen species can disrupt redox homeostasis, leading to oxidative or reductive stress that contributes to the pathogenesis of many malignancies, including cancer. From transformation and tumor initiation to metastatic dissemination, increasing reactive oxygen species in cancer cells can paradoxically promote or suppress the tumorigenic process, depending on the extent of redox stress, its spatiotemporal characteristics and the tumor microenvironment. Here we review how redox regulation influences tumorigenesis, highlighting therapeutic opportunities enabled by redox-related alterations in cancer cells.

DOI: https://doi.org/10.1038/s43018-024-00738-9
Cell Metab. 2024 Mar 26. pii: S1550-4131(24)00092-5. [Epub ahead of print]

Tumor-secreted FGF21 acts as an immune suppressor by rewiring cholesterol metabolism of CD8+T cells.

Cegui Hu, Wen Qiao, Xiang Li, Zhi-Kun Ning, Jiang Liu, Sumiya Dalangood, Hanjun Li, Xiang Yu, Zhen Zong, Zhenke Wen, Jun Gui.

DOI: https://doi.org/10.1016/j.cmet.2024.03.013
Cancers (Basel). 2024 Mar 18. pii: 1194. [Epub ahead of print]16(6):

Cachexia-Affected Survival Based on Inflammatory Parameters Compared to Complex Conventional Nutritional Assessments in Patients with Pancreatic Cancer and Other Gastrointestinal Tumors-The CONKO 020 Investigation.

Johanna W Meyer-Knees, Janina Falkenthal, Dominik Geisel, Christopher C M Neumann, Georg Hilfenhaus, Lars U Stephan, Wenzel Schöning, Thomas Malinka, Johann Pratschke, Sebastian Stintzing, Uwe Pelzer.

   BACKGROUND: Pancreatic adenocarcinoma (PDAC) is still a complex, devastating disease. Cachexia symptoms frequently impair patient survival. This accompanying syndrome is commonly diagnosed late, when clinical signs become evident. Early diagnosis using conventional measurement methods is often difficult, and the discrimination of this disease from cancer progression is challenging and often overlaps. The aim of this study was to analyze whether conventional nutritional assessments or laboratory biomarkers are better predictive tools for the early detection of patients at risk of reduced survival.
METHODS: We analyzed a prospective predefined cohort of 182 patients with gastrointestinal cancer, 120 patients with PDAC and-as controls-62 patients with other gastrointestinal adenocarcinoma (oAC), from whom we have sufficient data of protocol-defined conventional nutritional assessments, clinical data, and specific laboratory parameters.
RESULTS: at the time of tumor diagnosis, high inflammatory biomarkers (c-reactive protein (CRP), interleukin-6 (IL-6)) and albumin serum levels were associated with impaired OS in PDAC patients, but not in patients with oAC. Hemoglobin, body mass index (BMI), and bioelectrical assessments alone did not have a prognostic impact at the time of diagnosis. In a multivariate analysis, only CRP (HR 1.91 (1.25-2.92), p = 0.003) was found to be an independent prognostic factor in PDAC patients. Over the course of the disease in PDAC patients, inflammatory biomarkers, albumin, hemoglobin, and bioelectrical assessments were associated with impaired OS. In multivariate testing, CRP (HR 2.21 (1.38-3.55), p < 0.001) and albumin (HR 1.71 (1.05-2.77), p = 0.030) were found to be independent prognostic factors in PDAC patients.
CONCLUSION: Specifically for PDAC patients, high inflammatory index and albumin serum levels potentially represent a sufficient early surrogate marker to detect patients at high risk of impaired OS better than complex conventional methods. These findings could help to identify patients who may benefit from early therapeutic interventions.

Keywords:  CRP; IL-6; PDAC; cachexia; survival; systemic inflammation

DOI:  https://doi.org/10.3390/cancers16061194
Proc Natl Acad Sci U S A. 2024 Apr 02. 121(14): e2315509121

The MUC1-HIF-1α signaling axis regulates pancreatic cancer pathogenesis through polyamine metabolism remodeling.

Divya Murthy, Kuldeep S Attri, Voddu Suresh, Girish H Rajacharya, Carlos A Valenzuela, Ravi Thakur, Junzhang Zhao, Surendra K Shukla, Nina V Chaika, Drew LaBreck, Chinthalapally V Rao, Michael A Hollingsworth, Kamiya Mehla, Pankaj K Singh.

  Dysregulation of polyamine metabolism has been implicated in cancer initiation and progression; however, the mechanism of polyamine dysregulation in cancer is not fully understood. In this study, we investigated the role of MUC1, a mucin protein overexpressed in pancreatic cancer, in regulating polyamine metabolism. Utilizing pancreatic cancer patient data, we noted a positive correlation between MUC1 expression and the expression of key polyamine metabolism pathway genes. Functional studies revealed that knockdown of spermidine/spermine N1-acetyltransferase 1 (SAT1), a key enzyme involved in polyamine catabolism, attenuated the oncogenic functions of MUC1, including cell survival and proliferation. We further identified a regulatory axis whereby MUC1 stabilized hypoxia-inducible factor (HIF-1α), leading to increased SAT1 expression, which in turn induced carbon flux into the tricarboxylic acid cycle. MUC1-mediated stabilization of HIF-1α enhanced the promoter occupancy of the latter on SAT1 promoter and corresponding transcriptional activation of SAT1, which could be abrogated by pharmacological inhibition of HIF-1α or CRISPR/Cas9-mediated knockout of HIF1A. MUC1 knockdown caused a significant reduction in the levels of SAT1-generated metabolites, N1-acetylspermidine and N8-acetylspermidine. Given the known role of MUC1 in therapy resistance, we also investigated whether inhibiting SAT1 would enhance the efficacy of FOLFIRINOX chemotherapy. By utilizing organoid and orthotopic pancreatic cancer mouse models, we observed that targeting SAT1 with pentamidine improved the efficacy of FOLFIRINOX, suggesting that the combination may represent a promising therapeutic strategy against pancreatic cancer. This study provides insights into the interplay between MUC1 and polyamine metabolism, offering potential avenues for the development of treatments against pancreatic cancer.

Keywords:  MUC1; SAT1; hypoxia-inducible factors; pancreatic cancer; polyamine biosynthesis

DOI:  https://doi.org/10.1073/pnas.2315509121
PLoS One. 2024 ;19(3): e0300723

Inoculation of Pan02 cells produces tumor nodules in mouse pancreas: Characterization of a novel orthotopic pancreatic ductal adenocarcinoma tumor model for interventional studies.

James I Griffin, Xinyue Chen, Luqi Duan, Qingxin Mu, Rodney J Y Ho.

Preclinical models of cancer are vital for assessing and predicting efficacies and toxicities of novel treatments prior to testing in human subjects. Current pancreatic tumor models exhibit variable growth rates, unpredictable tumor size after implantation in non-native tissues, or require surgical implantation. Surgical implantation in the pancreas may produce not only unpredictable tumor uptake but could also elicit additional inflammatory responses. In searching for a pancreatic carcinoma cell that can be introduced into a mouse via simple injection, we found that Pan02, a murine ductal pancreatic adenocarcinoma derived from a pancreatic lesion of a C57BL/6 mouse, inoculated peritoneally can consistently produce pancreatic tumors. This intraperitoneal, but not intravenous, introduction of Pan02 cells leads to the attachment and growth of Pan02 in the pancreas before spreading to other tissues. Time-course tissue analysis indicates that the Pan02 cells first find, infiltrate, and grow within the pancreas, producing a pancreatic tumor model. This model appears to mimic pancreatic cancer development in humans and is the first reported use of Pan02 cells to produce orthotopic pancreatic and metastatic neoplasms in a mouse model without the need for tumor implantation within matrices or survival surgeries. This orthotopic pancreatic tumor model, with consistent tumor uptake, synchronized tumor development and survival, and predictable outcomes may enable and accelerate the preclinical evaluation of treatment candidates for pancreatic cancer.

DOI: https://doi.org/10.1371/journal.pone.0300723
bioRxiv. 2024 Mar 16. pii: 2024.03.14.584700. [Epub ahead of print]

EHMT2 Inactivation in Pancreatic Epithelial Cells Shapes the Transcriptional Landscape and Inflammation Response of the Whole Pancreas.

Gareth Pollin, Angela J Mathison, Thiago M de Assuncao, Anju Thomas, Lida Zeighami, Ann Salmonson, Hongfei Liu, Guillermo Urrutia, Pallavi Vankayala, Stephen J Pandol, Michael T Zimmermann, Juan Iovanna, Victor X Jin, Raul Urrutia, Gwen Lomberk.

The Euchromatic Histone Methyl Transferase Protein 2 (EHMT2), also known as G9a, deposits transcriptionally repressive chromatin marks that play pivotal roles in the maturation and homeostasis of multiple organs. Recently, we have shown that EHMT2 inactivation alters growth and immune gene expression networks, antagonizing KRAS-mediated pancreatic cancer initiation and promotion. Here, we elucidate the essential role of EHMT2 in maintaining a transcriptional landscape that protects organs from inflammation. Comparative RNA-seq studies between normal postnatal and young adult pancreatic tissue from EHMT2 conditional knockout animals ( EHMT2 fl/fl ) targeted to the exocrine pancreatic epithelial cells ( Pdx1-Cre and P48 Cre/+ ), reveal alterations in gene expression networks in the whole organ related to injury-inflammation-repair, suggesting an increased predisposition to damage. Thus, we induced an inflammation repair response in the EHMT2 fl/fl pancreas and used a data science-based approach to integrate RNA-seq-derived pathways and networks, deconvolution digital cytology, and spatial transcriptomics. We also analyzed the tissue response to damage at the morphological, biochemical, and molecular pathology levels. The EHMT2 fl/fl pancreas displays an enhanced injury-inflammation-repair response, offering insights into fundamental molecular and cellular mechanisms involved in this process. More importantly, these data show that conditional EHMT2 inactivation in exocrine cells reprograms the local environment to recruit mesenchymal and immunological cells needed to mount an increased inflammatory response. Mechanistically, this response is an enhanced injury-inflammation-repair reaction with a small contribution of specific EHMT2-regulated transcripts. Thus, this new knowledge extends the mechanisms underlying the role of the EHMT2-mediated pathway in suppressing pancreatic cancer initiation and modulating inflammatory pancreatic diseases.

DOI: https://doi.org/10.1101/2024.03.14.584700
J Pancreatol. 2024 Mar;7(1): 10-20

Acute pancreatitis: pathogenesis and emerging therapies.

Saif Zaman, Fred Gorelick.

  Acute pancreatitis is a severe inflammatory disorder with limited treatment options. Improved understanding of disease mechanisms has led to new and potential therapies. Here we summarize what we view as some of the most promising new therapies for treating acute pancreatitis, emphasizing the rationale of specific treatments based on disease mechanisms. Targeted pharmacologic interventions are highlighted. We explore potential treatment benefits and risks concerning reducing acute injury, minimizing complications, and improving long-term outcomes. Mechanisms associated with acute pancreatitis initiation, perpetuation, and reconstitution are highlighted, along with potential therapeutic targets and how these relate to new treatments.

Keywords:  Acinar cell; Acute pancreatitis; Calcium signaling; Transporters; Treatment

DOI:  https://doi.org/10.1097/JP9.0000000000000168
Science. 2024 Mar 29. 383(6690): 1484-1492

Pyrimidines maintain mitochondrial pyruvate oxidation to support de novo lipogenesis.

Umakant Sahu, Elodie Villa, Colleen R Reczek, Zibo Zhao, Brendan P O'Hara, Michael D Torno, Rohan Mishra, William D Shannon, John M Asara, Peng Gao, Ali Shilatifard, Navdeep S Chandel, Issam Ben-Sahra.

Cellular purines, particularly adenosine 5'-triphosphate (ATP), fuel many metabolic reactions, but less is known about the direct effects of pyrimidines on cellular metabolism. We found that pyrimidines, but not purines, maintain pyruvate oxidation and the tricarboxylic citric acid (TCA) cycle by regulating pyruvate dehydrogenase (PDH) activity. PDH activity requires sufficient substrates and cofactors, including thiamine pyrophosphate (TPP). Depletion of cellular pyrimidines decreased TPP synthesis, a reaction carried out by TPP kinase 1 (TPK1), which reportedly uses ATP to phosphorylate thiamine (vitamin B1). We found that uridine 5'-triphosphate (UTP) acts as the preferred substrate for TPK1, enabling cellular TPP synthesis, PDH activity, TCA-cycle activity, lipogenesis, and adipocyte differentiation. Thus, UTP is required for vitamin B1 utilization to maintain pyruvate oxidation and lipogenesis.

DOI: https://doi.org/10.1126/science.adh2771
Genome Biol. 2024 Mar 29. 25(1): 81

FixNCut: single-cell genomics through reversible tissue fixation and dissociation.

Laura Jiménez-Gracia, Domenica Marchese, Juan C Nieto, Ginevra Caratù, Elisa Melón-Ardanaz, Victoria Gudiño, Sara Roth, Kellie Wise, Natalie K Ryan, Kirk B Jensen, Xavier Hernando-Momblona, Joana P Bernardes, Florian Tran, Laura Katharina Sievers, Stefan Schreiber, Maarten van den Berge, Tessa Kole, Petra L van der Velde, Martijn C Nawijn, Philip Rosenstiel, Eduard Batlle, Lisa M Butler, Ian A Parish, Jasmine Plummer, Ivo Gut, Azucena Salas, Holger Heyn, Luciano G Martelotto.

  The use of single-cell technologies for clinical applications requires disconnecting sampling from downstream processing steps. Early sample preservation can further increase robustness and reproducibility by avoiding artifacts introduced during specimen handling. We present FixNCut, a methodology for the reversible fixation of tissue followed by dissociation that overcomes current limitations. We applied FixNCut to human and mouse tissues to demonstrate the preservation of RNA integrity, sequencing library complexity, and cellular composition, while diminishing stress-related artifacts. Besides single-cell RNA sequencing, FixNCut is compatible with multiple single-cell and spatial technologies, making it a versatile tool for robust and flexible study designs.

Keywords:  Cellular stress; RNA sequencing; Sample fixation; Single-cell genomics; Tissue dissociation

DOI:  https://doi.org/10.1186/s13059-024-03219-5
Methods Cell Biol. 2024 ;pii: S0091-679X(23)00114-0. [Epub ahead of print]183 317-333

Humanized mouse models for anti-cancer therapy.

Maria Francesca Baietti, Eleonora Leucci.

  Patient-derived xenograft (PDX) models are the golden standard for preclinical oncology as they can recapitulate the genotypic and phenotypic complexity of human tumors, thus enabling the development of effective therapeutic strategies. PDX models are typically established in immunocompromised animals that allow efficient growth of the xenografted tumor. Given the recent success of immune therapies in different tumors however, the establishment of humanized PDX models is critical to evaluate immune oncology drugs and/or combinations thereof. Here, we describe the detailed methods to obtain humanized PDX models for anti-cancer therapy testing.

Keywords:  Humanization; Immunotherapy; In vivo; PDX; Tumor models; Xenografts

DOI:  https://doi.org/10.1016/bs.mcb.2023.06.002
PLoS One. 2024 ;19(3): e0292189

p53 dosage can impede KrasG12D- and KrasQ61R-mediated tumorigenesis.

Özgün Le Roux, Jeffery I Everitt, Christopher M Counter.

Mice engineered with a G12D versus Q61R mutation in Kras exhibited differences in tumorigenesis. Namely, the incidence or grade of oral or forestomach squamous epithelial lesions was more prevalent in the KrasG12D background while hematolymphopoietic disease was more prevalent in the KrasQ61R background. Loss of the Trp53 gene encoding the tumor suppressor p53 enhances the ability of oncogenic Kras to initiate tumorigenesis in carcinogen and genetic models of lung cancer. Conversley, an extra copy of Trp53 (Super p53) was recently shown to suppress Kras-induced tumorigenesis in a genetic model of this disease. Given this, we evaluated whether an extra copy of Trp53 would alter tumorigenesis upon global activation of a modified Kras allele engineered with either a G12D or Q61R mutation. We report that an increase in p53 dosage significantly reduced the incidence or grade of oral and forestomach squamous tumors induced by either G12D and Q61R-mutant Kras. The incidence of myeloproliferative disease was also significantly reduced with increased p53 dosage in the KrasQ61R background. Both the percentage of mice with lung tumors and total number of adenomas per animal were unchanged. However, the incidence and grade of peripheral atypical alveolar hyperplasia was significantly decreased in both backgrounds with increased p53 dosage. Finally, the number of foci of bronchioloalveolar hyperplasia per animal significantly increased with increased p53 dosage in the KrasG12D background. These results suggest that an extra copy of p53 can impede oncogenic Kras driven tumorigenesis in some tissues.

DOI: https://doi.org/10.1371/journal.pone.0292189
Nat Commun. 2024 Mar 29. 15(1): 2767

Adhesion energy controls lipid binding-mediated endocytosis.

Raluca Groza, Kita Valerie Schmidt, Paul Markus Müller, Paolo Ronchi, Claire Schlack-Leigers, Ursula Neu, Dmytro Puchkov, Rumiana Dimova, Claudia Matthaeus, Justin Taraska, Thomas R Weikl, Helge Ewers.

Several bacterial toxins and viruses can deform membranes through multivalent binding to lipids for clathrin-independent endocytosis. However, it remains unclear, how membrane deformation and endocytic internalization are mechanistically linked. Here we show that many lipid-binding virions induce membrane deformation and clathrin-independent endocytosis, suggesting a common mechanism based on multivalent lipid binding by globular particles. We create a synthetic cellular system consisting of a lipid-anchored receptor in the form of GPI-anchored anti-GFP nanobodies and a multivalent globular binder exposing 180 regularly-spaced GFP molecules on its surface. We show that these globular, 40 nm diameter, particles bind to cells expressing the receptor, deform the plasma membrane upon adhesion and become endocytosed in a clathrin-independent manner. We explore the role of the membrane adhesion energy in endocytosis by using receptors with affinities varying over 7 orders of magnitude. Using this system, we find that once a threshold in adhesion energy is overcome to allow for membrane deformation, endocytosis occurs reliably. Multivalent, binding-induced membrane deformation by globular binders is thus sufficient for internalization to occur and we suggest it is the common, purely biophysical mechanism for lipid-binding mediated endocytosis of toxins and pathogens.

DOI: https://doi.org/10.1038/s41467-024-47109-7
bioRxiv. 2024 Mar 22. pii: 2024.03.19.585779. [Epub ahead of print]

Senolytic CAR T cells reverse aging-associated defects in intestinal regeneration and fitness.

Onur Eskiocak, Saria Chowdhury, Vyom Shah, Emmanuella Nnuji-John, Charlie Chung, Jacob A Boyer, Alexander S Harris, Jill Habel, Michel Sadelain, Semir Beyaz, Corina Amor.

Intestinal stem cells (ISCs) drive the rapid regeneration of the gut epithelium to maintain organismal homeostasis. Aging, however, significantly reduces intestinal regenerative capacity. While cellular senescence is a key feature of the aging process, little is known about the in vivo effects of senescent cells on intestinal fitness. Here, we identify the accumulation of senescent cells in the aging gut and, by harnessing senolytic CAR T cells to eliminate them, we uncover their detrimental impact on epithelial integrity and overall intestinal homeostasis in natural aging, injury and colitis. Ablation of intestinal senescent cells with senolytic CAR T cells in vivo or in vitro is sufficient to promote the regenerative potential of aged ISCs. This intervention improves epithelial integrity and mucosal immune function. Overall, these results highlight the ability of senolytic CAR T cells to rejuvenate the intestinal niche and demonstrate the potential of targeted cell therapies to promote tissue regeneration in aging organisms.

DOI: https://doi.org/10.1101/2024.03.19.585779
Cancer Discov. 2024 Mar 27.

Paradoxical activation of oncogenic signaling as a cancer treatment strategy.

Matheus Henrique Dias, Anoek Friskes, Siying Wang, Joao M Fernandes Neto, Frank van Gemert, Soufiane Mourragui, Chrysa Papagianni, Hendrik J Kuiken, Sara Mainardi, Daniel Alvarez-Villanueva, Cor Lieftink, Ben Morris, Anna Dekker, Emma van Dijk, Lieke H S Wilms, Marcelo S da Silva, Robin A Jansen, Antonio Mulero-Sanchez, Elke Malzer, August Vidal, Cristina Santos, Ramon Salazar, Rosangela A M Wailemann, Thompson E P Torres, Giulia De Conti, Jonne A Raaijmakers, Petur Snaebjornsson, Shengxian Yuan, Wenxin Qin, John S Kovach, Hugo A Armelin, Hein Te Riele, Alexander van Oudernaarden, Haojie Jin, Roderick L Beijersbergen, Alberto Villanueva, Rene H Medema, Rene Bernards.

Cancer homeostasis depends on a balance between activated oncogenic pathways driving tumorigenesis and engagement of stress-response programs that counteract the inherent toxicity of such aberrant signaling. While inhibition of oncogenic signaling pathways has been explored extensively, there is increasing evidence that overactivation of the same pathways can also disrupt cancer homeostasis and cause lethality. We show here that inhibition of Protein Phosphatase 2A (PP2A) hyperactivates multiple oncogenic pathways and engages stress responses in colon cancer cells. Genetic and compound screens identify combined inhibition of PP2A and WEE1 as synergistic in multiple cancer models by collapsing DNA replication and triggering premature mitosis followed by cell death. This combination also suppressed the growth of patient-derived tumors in vivo. Remarkably, acquired resistance to this drug combination suppressed the ability of colon cancer cells to form tumors in vivo. Our data suggest that paradoxical activation of oncogenic signaling can result in tumor suppressive resistance.

DOI: https://doi.org/10.1158/2159-8290.CD-23-0216
Nat Chem. 2024 Mar 29.

Expanding the molecular language of protein liquid-liquid phase separation.

Shiv Rekhi, Cristobal Garcia Garcia, Mayur Barai, Azamat Rizuan, Benjamin S Schuster, Kristi L Kiick, Jeetain Mittal.

Understanding the relationship between a polypeptide sequence and its phase separation has important implications for analysing cellular function, treating disease and designing novel biomaterials. Several sequence features have been identified as drivers for protein liquid-liquid phase separation (LLPS), schematized as a 'molecular grammar' for LLPS. Here we further probe how sequence modulates phase separation and the material properties of the resulting condensates, targeting sequence features previously overlooked in the literature. We generate sequence variants of a repeat polypeptide with either no charged residues, high net charge, no glycine residues or devoid of aromatic or arginine residues. All but one of 12 variants exhibited LLPS, albeit to different extents, despite substantial differences in composition. Furthermore, we find that all the condensates formed behaved like viscous fluids, despite large differences in their viscosities. Our results support the model of multiple interactions between diverse residue pairs-not just a handful of residues-working in tandem to drive the phase separation and dynamics of condensates.

DOI: https://doi.org/10.1038/s41557-024-01489-x
Curr Biol. 2024 Mar 25. pii: S0960-9822(24)00148-9. [Epub ahead of print]34(6): R244-R246

Cancer cell invasion: Caveolae and invadosomes are partners in crime.

Laura Sotodosos-Alonso, Miguel A Del Pozo.

During cancer progression, tumor cells need to disseminate by remodeling the extracellular tumor matrix. A recent study sheds light on the intricate cooperation between caveolae and invadosomes that facilitates the spread of cancer cells.

DOI: https://doi.org/10.1016/j.cub.2024.02.006
Nat Metab. 2024 Mar 27.

Non-invasive measurements of blood glucose levels by time-gating mid-infrared optoacoustic signals.

Nasire Uluç, Sarah Glasl, Francesca Gasparin, Tao Yuan, Hailong He, Dominik Jüstel, Miguel A Pleitez, Vasilis Ntziachristos.

Non-invasive glucose monitoring (NIGM) represents an attractive alternative to finger pricking for blood glucose assessment and management of diabetes. Nevertheless, current NIGM techniques do not measure glucose concentrations in blood but rely on indirect bulk measurement of glucose in interstitial fluid, where glucose is diluted and glucose dynamics are different from those in the blood, which impairs NIGM accuracy. Here we introduce a new biosensor, termed depth-gated mid-infrared optoacoustic sensor (DIROS), which allows, for the first time, non-invasive glucose detection in blood-rich volumes in the skin. DIROS minimizes interference caused by the stratum corneum and other superficial skin layers by time-gating mid-infrared optoacoustic signals to enable depth-selective localization of glucose readings in skin. In measurements on the ears of (female) mice, DIROS displays improved accuracy over bulk-tissue glucose measurements. Our work demonstrates how signal localization can improve NIGM accuracy and positions DIROS as a holistic approach, with high translational potential, that addresses a key limitation of current NIGM methods.

DOI: https://doi.org/10.1038/s42255-024-01016-9
Cancers (Basel). 2024 Mar 18. pii: 1183. [Epub ahead of print]16(6):

Molecular Pathology of Pancreatic Cystic Lesions with a Focus on Malignant Progression.

Yan Hu, Dan Jones, Ashwini K Esnakula, Somashekar G Krishna, Wei Chen.

  The malignant progression of pancreatic cystic lesions (PCLs) remains understudied with a knowledge gap, yet its exploration is pivotal for effectively stratifying patient risk and detecting cancer at its earliest stages. Within this review, we delve into the latest discoveries on the molecular level, revealing insights into the IPMN molecular landscape and revised progression model, associated histologic subtypes, and the role of inflammation in the pathogenesis and malignant progression of IPMN. Low-grade PCLs, particularly IPMNs, can develop into high-grade lesions or invasive carcinoma, underscoring the need for long-term surveillance of these lesions if they are not resected. Although KRAS and GNAS remain the primary oncogenic drivers of neoplastic development in IPMNs, additional genes that are important in tumorigenesis have been recently identified by whole exome sequencing. A more complete understanding of the genes involved in the molecular progression of IPMN is critical for effective monitoring to minimize the risk of malignant progression. Complicating these strategies, IPMNs are also frequently multifocal and multiclonal, as demonstrated by comparative molecular analysis. Algorithms for preoperative cyst sampling and improved radiomic techniques are emerging to model this spatial and temporal genetic heterogeneity better. Here, we review the molecular pathology of PCLs, focusing on changes associated with malignant progression. Developing models of molecular risk stratification in PCLs which can complement radiologic and clinical features, facilitate the early detection of pancreatic cancer, and enable the development of more personalized surveillance and management strategies are summarized.

Keywords:  EUS nCLE; IPMN; histologic subtypes; malignant progression; molecular mechanisms; pancreatic cancer; risk stratification; tumorigenesis

DOI:  https://doi.org/10.3390/cancers16061183