bims-miptne 2024-08-18 papers

bims-miptne

Biomed News

on Mitochondrial permeability transition pore-dependent necrosis

Issue of 2024–08–18
nine papers selected by
Oluwatobi Samuel Adegbite, University of Liverpool

Mitochondrial permeability transition dictates mitochondrial maturation upon switch in cellular identity of hematopoietic precursors.
TRPC6 regulates necroptosis in myocardial ischemia/reperfusion injury via Ca2+/CaMKII signaling pathway.
Mitochondrial Ca 2+ controls pancreatic cancer growth and metastasis by regulating epithelial cell plasticity.
Engineered Mitochondrial Transplantation as An Anti-Aging Therapy.
Mitochondrial complex I promotes kidney cancer metastasis.
Mfn2 induces NCLX-mediated calcium release from mitochondria.
COA6 promotes the oncogenesis and progression of breast cancer by oxidative phosphorylation pathway.
Deregulation of mitochondrial gene expression in cancer: mechanisms and therapeutic opportunities.
Exercise-downregulated CD300E acted as a negative prognostic implication and tumor-promoted role in pan-cancer.

Commun Biol. 2024 Aug 09. 7(1): 967

Mitochondrial permeability transition dictates mitochondrial maturation upon switch in cellular identity of hematopoietic precursors.

Sandeep P Dumbali, Paulina D Horton, Travis I Moore, Pamela L Wenzel.

The mitochondrial permeability transition pore (mPTP) is a supramolecular channel that regulates exchange of solutes across cristae membranes, with executive roles in mitochondrial function and cell death. The contribution of the mPTP to normal physiology remains debated, although evidence implicates the mPTP in mitochondrial inner membrane remodeling in differentiating progenitor cells. Here, we demonstrate that strict control over mPTP conductance shapes metabolic machinery as cells transit toward hematopoietic identity. Cells undergoing the endothelial-to-hematopoietic transition (EHT) tightly control chief regulatory elements of the mPTP. During EHT, maturing arterial endothelium restricts mPTP activity just prior to hematopoietic commitment. After transition in cellular identity, mPTP conductance is restored. In utero treatment with NIM811, a molecule that blocks sensitization of the mPTP to opening by Cyclophilin D (CypD), amplifies oxidative phosphorylation (OXPHOS) in hematopoietic precursors and increases hematopoiesis in the embryo. Additionally, differentiating pluripotent stem cells (PSCs) acquire greater organization of mitochondrial cristae and hematopoietic activity following knockdown of the CypD gene, Ppif. Conversely, knockdown of Opa1, a GTPase critical for proper cristae architecture, induces cristae irregularity and impairs hematopoiesis. These data elucidate a mechanism that regulates mitochondrial maturation in hematopoietic precursors and underscore a role for the mPTP in the acquisition of hematopoietic fate.

DOI: https://doi.org/10.1038/s42003-024-06671-y
Cell Signal. 2024 Aug 10. pii: S0898-6568(24)00312-7. [Epub ahead of print]122 111344

TRPC6 regulates necroptosis in myocardial ischemia/reperfusion injury via Ca2+/CaMKII signaling pathway.

Junhao Li, Jiaji Zhang, Yunlong Zhong, Dongge Xie, Han Han, Zhongqing Zhang, Yong Liu, Shoutian Li.

  Myocardial ischemia-reperfusion injury (MIRI) frequently complicates postoperative cardiovascular disease treatment. Necroptosis, a cell death mechanism similar to apoptosis, is regulated by specific signaling pathways and plays an important role in MIRI. Receptor-interacting protein 3 (RIP3), a key protein regulating necroptosis during MIRI, directly phosphorylates calmodulin-dependent protein kinase II (CaMKII). Leading to mitochondrial permeablity transition pore (mPTP) opening and inducing necroptosis. Transient receptor potential canonical channel 6 (TRPC6) regulats Ca2+ entry, is linked to CaMKII as an important upstream effector. However, the connection between TRPC6 and MIRI necroptosis remains unclear. The study aimed to investigate the relationship between TRPC6 and MIRI necroptosis, with a specific focus on elucidating the role of TRPC6 in regulating CaMKII phosphorylation during cardiac necroptosis via Ca2+ modulation. METHODS AND RESULTS: The experiment used wild-type (WT) and TRPC6 knockout (TRPC6-/-) mice for I/R model construction, and H9c2 myocardial cell line for H/R model. After ischemia-reperfusion (I/R), TRPC6 protein levels in mice significantly increased, exacerbating myocardial injury, infarct size (IS), and cardiac function in WT mice. In contrast, TRPC6 knockout attenuated myocardial injury, IS, and improved cardiac function. The results showed a significant correlation between changes in CaMKII and TRPC6. TRPC6 knockout led to decreased intracellular calcium levels, CaMKII phosphorylation, reactive oxygen species levels, mPTP opening, and improve mitochondrial structure. CONCLUSION: I/R upregulates TRPC6, which mediates Ca2+ entry and CaMKII phosphorylation, exacerbates oxidative stress, and induces necroptosis. These findings suggest a potential therapeutic avenue for mitigating MIRI by targeting TRPC6.

Keywords:  Calcium overload; Myocardial ischemia-reperfusion; Necroptosis; Oxidative stress; TRPC6

DOI:  https://doi.org/10.1016/j.cellsig.2024.111344
bioRxiv. 2024 Aug 09. pii: 2024.08.08.607195. [Epub ahead of print]

Mitochondrial Ca 2+ controls pancreatic cancer growth and metastasis by regulating epithelial cell plasticity.

Jillian S Weissenrieder, Jessica Peura, Usha Paudel, Nikita Bhalerao, Natalie Weinmann, Calvin Johnson, Maximilian Wengyn, Rebecca Drager, Emma Elizabeth Furth, Karl Simin, Marcus Ruscetti, Ben Z Stanger, Anil K Rustgi, Jason R Pitarresi, J Kevin Foskett.

Endoplasmic reticulum to mitochondria Ca 2+ transfer is important for cancer cell survival, but the role of mitochondrial Ca 2+ uptake through the mitochondrial Ca 2+ uniporter (MCU) in pancreatic adenocarcinoma (PDAC) is poorly understood. Here, we show that increased MCU expression is associated with malignancy and poorer outcomes in PDAC patients. In isogenic murine PDAC models, Mcu deletion ( Mcu KO ) ablated mitochondrial Ca 2+ uptake, which reduced proliferation and inhibited self-renewal. Orthotopic implantation of MCU-null tumor cells reduced primary tumor growth and metastasis. Mcu deletion reduced the cellular plasticity of tumor cells by inhibiting epithelial-to-mesenchymal transition (EMT), which contributes to metastatic competency in PDAC. Mechanistically, the loss of mitochondrial Ca 2+ uptake reduced expression of the key EMT transcription factor Snail and secretion of the EMT-inducing ligand TGFβ. Snail re-expression and TGFβ treatment rescued deficits in Mcu KO cells and restored their metastatic ability. Thus, MCU may present a therapeutic target in PDAC to limit cancer-cell-induced EMT and metastasis.

DOI: https://doi.org/10.1101/2024.08.08.607195
Aging Dis. 2024 Jul 19.

Engineered Mitochondrial Transplantation as An Anti-Aging Therapy.

Rui Zhao, Chen Dong, Qian Liang, Jianlin Gao, Chi Sun, Zhifeng Gu, Yujuan Zhu.

Aging is an inevitable and complex biological process involving multi-factorial mechanisms. Mitochondrial dysfunction is a critical factor in the aging process, characterized by a decline in mitochondrial quality and activity, leading to aging and aging-related diseases. Therefore, mitochondria have become an attractive target in anti-aging therapies. Several senolytic drugs targeting mitochondria and antioxidant agents have been used in anti-aging research in the past few years. However, these strategies may cause adverse effects with long-term medication. In this extensive review, we propose "mitochondrial transplantation," which transfers healthy mitochondria from donor cells to recipient cells to replace damaged or dysfunctional mitochondria, as a new alternative strategy for treating mitochondrial dysfunction and aging-associated diseases. In this review, we introduce the contemporary landscape of mitochondrial transplantation, then discuss intensely the successful applications of mitochondrial transplantation therapy in aging diseases such as neurodegenerative diseases, cardiovascular aging, and reproductive aging, highlighting its translational potential. Finally, we summarize and prospect the challenges and opportunities mitochondrial transplantation faces in anti-aging therapy.

DOI: https://doi.org/10.14336/AD.2024.0231
Nature. 2024 Aug 14.

Mitochondrial complex I promotes kidney cancer metastasis.

Divya Bezwada, Luigi Perelli, Nicholas P Lesner, Ling Cai, Bailey Brooks, Zheng Wu, Hieu S Vu, Varun Sondhi, Daniel L Cassidy, Stacy Kasitinon, Sherwin Kelekar, Feng Cai, Arin B Aurora, McKenzie Patrick, Ashley Leach, Rashed Ghandour, Yuanyuan Zhang, Duyen Do, Phyllis McDaniel, Jessica Sudderth, Dennis Dumesnil, Sara House, Tracy Rosales, Alan M Poole, Yair Lotan, Solomon Woldu, Aditya Bagrodia, Xiaosong Meng, Jeffrey A Cadeddu, Prashant Mishra, Javier Garcia-Bermudez, Ivan Pedrosa, Payal Kapur, Kevin D Courtney, Craig R Malloy, Giannicola Genovese, Vitaly Margulis, Ralph J DeBerardinis.

Most kidney cancers are metabolically dysfunctional1-4, but how this dysfunction affects cancer progression in humans is unknown. We infused 13C-labelled nutrients in over 80 patients with kidney cancer during surgical tumour resection. Labelling from [U-13C]glucose varies across subtypes, indicating that the kidney environment alone cannot account for all tumour metabolic reprogramming. Compared with the adjacent kidney, clear cell renal cell carcinomas (ccRCCs) display suppressed labelling of tricarboxylic acid (TCA) cycle intermediates in vivo and in ex vivo organotypic cultures, indicating that suppressed labelling is tissue intrinsic. [1,2-13C]acetate and [U-13C]glutamine infusions in patients, coupled with measurements of respiration in isolated human kidney and tumour mitochondria, reveal lower electron transport chain activity in ccRCCs that contributes to decreased oxidative and enhanced reductive TCA cycle labelling. However, ccRCC metastases unexpectedly have enhanced TCA cycle labelling compared with that of primary ccRCCs, indicating a divergent metabolic program during metastasis in patients. In mice, stimulating respiration or NADH recycling in kidney cancer cells is sufficient to promote metastasis, whereas inhibiting electron transport chain complex I decreases metastasis. These findings in humans and mice indicate that metabolic properties and liabilities evolve during kidney cancer progression, and that mitochondrial function is limiting for metastasis but not growth at the original site.

DOI: https://doi.org/10.1038/s41586-024-07812-3
bioRxiv. 2024 Aug 13. pii: 2024.08.05.606704. [Epub ahead of print]

Mfn2 induces NCLX-mediated calcium release from mitochondria.

Panagiota Kolitsida, Akash Saha, Andrew W Caliri, Essam Assali, Alejandro Martorell Riera, Samuel Itskanov, Catalina S Magana, Bjorn Stork, Orian S Shirihai, Israel Sekler, Carla M Koehler, Alexander M van der Bliek.

Mfn2 is a mitochondrial outer membrane fusion protein with the additional role of tethering mitochondria to the ER. Here, we describe a novel connection between Mfn2 and calcium release from mitochondria. We show that Mfn2 controls the mitochondrial inner membrane sodium-calcium exchange protein NCLX, which is a major source for calcium release from mitochondria. This discovery was made with the fungal toxin Phomoxanthone (PXA), which induces calcium release from mitochondria. PXA-induced calcium release is blocked by a chemical inhibitor of NCLX, while NCLX and Mfn2 deletions both also prevent PXA-induced calcium release. CETSA experiments show that PXA directly targets Mfn2, which likely controls NCLX through physical interactions since co-immunoprecipitation and proximity ligation assays show increased association between Mfn2 and NCLX upon treatment with PXA. Interactions between Mfn2 and NCLX also increase when cells are treated with mitochondrial ROS-inducing conditions, such as oligomycin treatment of respiring cells, while the interactions do not increase in Oma1 -/- cells. It seems likely that opening of cristae by Oma1-mediated cleavage of Opa1 promotes translocation of NCLX from cristae to the rim where it can come into contact with Mfn2 thus promoting PXA-induced calcium release from mitochondria. These results therefore delineate a pathway that connects ROS produced inside mitochondria with calcium release and signaling in the cytosol.

DOI: https://doi.org/10.1101/2024.08.05.606704
J Cancer. 2024 ;15(15): 5072-5084

COA6 promotes the oncogenesis and progression of breast cancer by oxidative phosphorylation pathway.

Xiaoxia Jin, Xinyan Chen, Haiyan Yu, Yushan Liu, Xiaoyun Lu, Haibing Yin, Wencheng Dai.

  Mitochondrial oxidative phosphorylation (OXPHOS) has long been considered the primary energy source in breast cancer cells. Cytochrome c oxidase assembly factor 6 (COA6), which functions as a metal chaperone to transport copper to complex Ⅳ during the OXPHOS process, plays a crucial role in the carcinogenesis of lung adenocarcinoma. Nevertheless, its specific function in breast cancer is undefined. The present investigation aimed to clarify COA6's expression profile and regulatory functions in breast cancer, as well as to unveil its underlying mechanisms. Initially, our findings revealed a significant upregulation of COA6 in breast cancer, as evidenced by an analysis of the TCGA database and tissue microarrays. This upregulation correlated with tumor size and histological grade. Additionally, survival analysis revealed that elevated COA6 amounts were correlated with decreased overall survival (OS) in breast cancer. To delve deeper into the functions of COA6, both COA6-overexpressing and COA6-knockdown breast cancer cell models were established. These experiments demonstrated COA6 is pivotal in regulating cell proliferation, apoptosis, migration, and invasion, thereby promoting cancer progression in vitro. Notably, functional enrichment analysis indicated COA6 might be involved in breast cancer progression by modulating oxidative phosphorylation (OXPHOS). Collectively, this study reveals an overt tumorigenic role for COA6 in breast cancer and sheds light on its potential mechanisms, offering valuable therapeutic targets for breast cancer therapy.

Keywords:  Breast cancer; COA6; OXPHOS; The Cancer Genome Atlas (TCGA)

DOI:  https://doi.org/10.7150/jca.98570
Br J Cancer. 2024 Aug 14.

Deregulation of mitochondrial gene expression in cancer: mechanisms and therapeutic opportunities.

Mariah J Berner, Steven W Wall, Gloria V Echeverria.

"Reprogramming of energy metabolism" was first considered an emerging hallmark of cancer in 2011 by Hanahan & Weinberg and is now considered a core hallmark of cancer. Mitochondria are the hubs of metabolism, crucial for energetic functions and cellular homeostasis. The mitochondrion's bacterial origin and preservation of their own genome, which encodes proteins and RNAs essential to their function, make them unique organelles. Successful generation of mitochondrial gene products requires coordinated functioning of the mitochondrial 'central dogma,' encompassing all steps necessary for mtDNA to yield mitochondrial proteins. Each of these processes has several levels of regulation, including mtDNA accessibility and protection through mtDNA packaging and epigenetic modifications, mtDNA copy number through mitochondrial replication, mitochondrial transcription through mitochondrial transcription factors, and mitochondrial translation through mitoribosome formation. Deregulation of these mitochondrial processes in the context of cancers has only recently been appreciated, with most studies being correlative in nature. Nonetheless, numerous significant associations of the mitochondrial central dogma with pro-tumor phenotypes have been documented. Several studies have even provided mechanistic insights and further demonstrated successful pharmacologic targeting strategies. Based on the emergent importance of mitochondria for cancer biology and therapeutics, it is becoming increasingly important that we gain an understanding of the underpinning mechanisms so they can be successfully therapeutically targeted. It is expected that this mechanistic understanding will result in mitochondria-targeting approaches that balance anticancer potency with normal cell toxicity. This review will focus on current evidence for the dysregulation of mitochondrial gene expression in cancers, as well as therapeutic opportunities on the horizon.

DOI: https://doi.org/10.1038/s41416-024-02817-1
Front Immunol. 2024 ;15 1437068

Exercise-downregulated CD300E acted as a negative prognostic implication and tumor-promoted role in pan-cancer.

Zhiwen Luo, Jinguo Zhu, Rui Xu, Renwen Wan, Yanwei He, Yisheng Chen, Qing Wang, Shuo Chen, Shiyi Chen.

   Background: Breast cancer ranks as one of the most prevalent malignancies among women globally, with increasing incidence rates. Physical activity, particularly exercise, has emerged as a potentially significant modifier of cancer prognosis, influencing tumor biology and patient outcomes.
Methods: Using a murine breast cancer model, we established a control and an exercise group, where the latter was subjected to 21 days of voluntary running. RNA Sequencing, bioinformatics analysis, pan-cancer analysis, and cell experiments were performed to validate the underlying mechanisms.
Results: We observed that exercise significantly reduced tumor size and weight, without notable changes in body weight, suggesting that physical activity can modulate tumor dynamics. mRNA sequencing post-exercise revealed substantial downregulation of CD300E in the exercise group, accompanied by alterations in critical pathways such as MicroRNAs in cancers and the Calcium signaling pathway. Expanding our analysis to a broader cancer spectrum, CD300E demonstrated significant expression variability across multiple cancer types, with pronounced upregulation in myeloma, ovarian, lung, and colorectal cancers. This upregulation was correlated with poorer prognostic outcomes, emphasizing CD300E's potential role as a prognostic marker and therapeutic target. Moreover, CD300E expression was associated with cancer cell proliferation and apoptosis.
Conclusion: The study highlights the dual role of exercise in modulating gene expression relevant to tumor growth and the potential of CD300E as a target in cancer therapeutics. Further research is encouraged to explore the mechanisms by which exercise and CD300E influence cancer progression and to develop targeted strategies that could enhance patient outcomes in clinical settings.

Keywords:  CD300E; bioinformatics; breast cancer; pan-cancer; physical exercise; proliferation

DOI:  https://doi.org/10.3389/fimmu.2024.1437068