bims-instec Biomed News
on Intestinal stem cells and chemoresistance in colon cancer and intestinal regeneration
Issue of 2024–01–14
eleven papers selected by
Maria-Virginia Giolito, Université Catholique de Louvain



  1. Cell Death Dis. 2024 Jan 10. 15(1): 27
      Intestinal epithelial renewal, which depends on the proliferation and differentiation of intestinal stem cells (ISCs), is essential for epithelial homoeostasis. Understanding the mechanism controlling ISC activity is important. We found that death receptor 5 (DR5) gene deletion (DR5-/-) mice had impaired epithelial absorption and barrier function, resulting in delayed weight gain, which might be related to the general reduction of differentiated epithelial cells. In DR5-/- mice, the expression of ISC marker genes, the number of Olfm4+ ISCs, and the number of Ki67+ and BrdU+ cells in crypt were reduced. Furthermore, DR5 deletion inhibited the expression of lineage differentiation genes driving ISC differentiation into enterocytes, goblet cells, enteroendocrine cells, and Paneth cells. Therefore, DR5 gene loss may inhibit the intestinal epithelial renewal by dampening ISC activity. The ability of crypts from DR5-/- mice to form organoids decreased, and selective DR5 activation by Bioymifi promoted organoid growth and the expression of ISC and intestinal epithelial cell marker genes. Silencing of endogenous DR5 ligand TRAIL in organoids down-regulated the expression of ISC and intestinal epithelial cell marker genes. So, DR5 expressed in intestinal crypts was involved in the regulation of ISC activity. DR5 deletion in vivo or activation in organoids inhibited or enhanced the activity of Wnt, Notch, and BMP signalling through regulating the production of Paneth cell-derived ISC niche factors. DR5 gene deletion caused apoptosis and DNA damage in transit amplifying cells by inhibiting ERK1/2 activity in intestinal crypts. Inhibition of ERK1/2 with PD0325901 dampened the ISC activity and epithelial regeneration. In organoids, when Bioymifi's effect in activating ERK1/2 activity was completely blocked by PD0325901, its role in stimulating ISC activity and promoting epithelial regeneration was also eliminated. In summary, DR5 in intestinal crypts is essential for ISC activity during epithelial renewal under homoeostasis.
    DOI:  https://doi.org/10.1038/s41419-023-06409-4
  2. Cells. 2023 Dec 25. pii: 46. [Epub ahead of print]13(1):
      Tissue radiosensitivity plays a critical role in the overall outcome of radiation therapy. Identifying characteristics that predict how a patient may respond to radiotherapy enables clinicians to maximize the therapeutic window. Limited clinical data have suggested a difference in male and female radiotherapy outcomes. Radiotherapy for gastrointestinal malignancy is still a challenge due to intestinal sensitivity to radiation toxicity. In this manuscript, we demonstrated sex-specific differences in intestinal epithelial radiosensitivity. In a mouse model of abdominal irradiation, we observed a significant increase in oxidative stress and injury in males compared to females. Lgr5+ve intestinal stem cells from male mice showed higher sensitivity to radiation-induced toxicity. However, sex-specific differences in intestinal radiosensitivity were not dependent on sex hormones, as we demonstrated similar sex-specific radiosensitivity differences in pre-pubescent mice. In an ex vivo study, we found that patient-derived intestinal organoid (PID) from males showed higher sensitivity to radiation compared to females as evident from loss of budding crypts, organoid size, and membrane integrity. Transcriptomic analysis of human Lgr5+ intestinal stem cells suggested radiation-induced upregulation of mitochondrial oxidative metabolism in males compared to females, a possible mechanism for radiosensitivity differences.
    Keywords:  ISCs; LGR5+; oxidative stress; radiosensitivity
    DOI:  https://doi.org/10.3390/cells13010046
  3. bioRxiv. 2023 Dec 23. pii: 2023.12.21.572810. [Epub ahead of print]
      Approximately 40% of colorectal cancer (CRC) cases are characterized by KRAS mutations, rendering them insensitive to most CRC therapies. While the reasons for this resistance remain incompletely understood, one key aspect is genetic complexity: in CRC, oncogenic KRAS is most commonly paired with mutations that alter WNT and P53 activities ("RAP"). Here, we demonstrate that elevated WNT activity upregulates canonical (NF-κB) signalling in both Drosophila and human RAS mutant tumours. This upregulation required Toll-1 and Toll-9 and resulted in reduced efficacy of RAS pathway targeted drugs such as the MEK inhibitor trametinib. Inhibiting WNT activity pharmacologically significantly suppressed trametinib resistance in RAP tumours and more genetically complex RAP-containing 'patient avatar' models. WNT/MEK drug inhibitor combinations were further improved by targeting brm, shg, ago, rhoGAPp190 and upf1, highlighting these genes as candidate biomarkers for patients sensitive to this duel approach. These findings shed light on how genetic complexity impacts drug resistance and proposes a therapeutic strategy to reverse this resistance.
    DOI:  https://doi.org/10.1101/2023.12.21.572810
  4. Biochim Biophys Acta Mol Cell Res. 2024 Jan 10. pii: S0167-4889(24)00001-6. [Epub ahead of print] 119658
       BACKGROUND: We have previously shown that non-curative chemotherapy imposes fetal conversion and high metastatic capacity to cancer cells. From the set of genes differentially expressed in Chemotherapy Resistant Cells, we obtained a characteristic fetal intestinal cell signature that is present in a group of untreated tumors and is sufficient to predict patient prognosis. A feature of this fetal signature is the loss of CDX1.
    METHODS: We have analyzed transcriptomic data in public datasets and performed immunohistochemistry analysis of paraffin embedded tumor samples from two cohorts of colorectal cancer patients.
    RESULTS: We demonstrated that low levels of CDX1 are sufficient to identify patients with poorest outcome at the early tumor stages II and III. Presence tumor areas that are negative for CDX1 staining in stage I cancers is associated with tumor relapse.
    CONCLUSIONS: Our results reveal the actual possibility of incorporating CDX1 immunostaining as a valuable biomarker for CRC patients.
    Keywords:  CDX1; Colorectal cancer; Fetal conversion; Patient prognosis
    DOI:  https://doi.org/10.1016/j.bbamcr.2024.119658
  5. Cell Mol Life Sci. 2024 Jan 12. 81(1): 28
      Although amplifications and mutations in receptor tyrosine kinases (RTKs) act as bona fide oncogenes, in most cancers, RTKs maintain moderate expression and remain wild-type. Consequently, cognate ligands control many facets of tumorigenesis, including resistance to anti-RTK therapies. Herein, we show that the ligands for the RTKs MET and RON, HGF and HGFL, respectively, are synthesized as inactive precursors that are activated by cellular proteases. Our newly generated HGF/HGFL protease inhibitors could overcome both de novo and acquired cetuximab resistance in colorectal cancer (CRC). Conversely, HGF overexpression was necessary and sufficient to induce cetuximab resistance and loss of polarity. Moreover, HGF-induced cetuximab resistance could be overcome by the downstream MET inhibitor, crizotinib, and upstream protease inhibitors. Additionally, HAI-1, an endogenous inhibitor of HGF proteases, (i) was downregulated in CRC, (ii) exhibited increased genomic methylation that correlated with poor prognosis, (iii) HAI-1 expression correlated with cetuximab response in a panel of cancer cell lines, and (iv) exogenous addition of recombinant HAI-1 overcame cetuximab resistance in CC-HGF cells. Thus, we describe a targetable, autocrine HAI-1/Protease/HGF/MET axis in cetuximab resistance in CRC.
    Keywords:  3D culture; Cetuximab; Colorectal cancer; Crizotinib; Drug resistance; EGFR; HAI-1; HGF; MET; Protease inhibition
    DOI:  https://doi.org/10.1007/s00018-023-05071-5
  6. Cancer Lett. 2024 Jan 10. pii: S0304-3835(24)00026-0. [Epub ahead of print] 216632
      WNT/β-catenin signaling is aberrantly activated in colorectal cancer (CRC) mainly by loss-of-function mutations in adenomatous polyposis coli (APC) and is involved in tumor progression. Tankyrase inhibitors, which suppress WNT/β-catenin signaling, are currently in pre-clinical and clinical trials. However, the mechanisms of resistance to tankyrase inhibitors remain unclear. In this study, we established tankyrase inhibitor-resistant CRC cells, JC73-RK100, from APC-mutated patient-derived CRC cells. JC73-RK100 cells and several CRC cell lines were sensitive to tankyrase inhibitors at low concentrations but were resistant at high concentrations, showing an intrinsic/acquired bell-shaped dose response. Mechanistically, tankyrase inhibitors at high concentrations promoted BRD3/4-dependent E2F target gene transcription and over-activated cell cycle progression in these cells. BET inhibitors canceled the bell-shaped dose response to tankyrase inhibitors. Combination of tankyrase and BET inhibitors significantly suppress tumor growth in a mouse xenograft model. These observations suggest that the combination of tankyrase and BET inhibitors may be a useful therapeutic approach to overcome the resistance of a subset of CRCs to tankyrase inhibitors.
    Keywords:  BET inhibitor; Colorectal cancer; Drug resistance; Tankyrase; WNT/β-catenin signaling
    DOI:  https://doi.org/10.1016/j.canlet.2024.216632
  7. bioRxiv. 2023 Dec 23. pii: 2023.12.21.572817. [Epub ahead of print]
      Colorectal cancer (CRC) is the second most deadly cancer worldwide. One key reason is the failure of therapies that target RAS proteins, which represent approximately 40% of CRC cases. Despite the recent discovery of multiple alternative signalling pathways that contribute to resistance, durable therapies remain an unmet need. Here, we use liquid chromatography/mass spectrometry (LC/MS) analyses on Drosophila CRC tumour models to identify multiple metabolites in the glucuronidation pathway-a toxin clearance pathway-as upregulated in trametinib-resistant RAS/APC/P53 ("RAP") tumours compared to trametinib-sensitive RASG12V tumours. Elevating glucuronidation was sufficient to direct trametinib resistance in RASG12V animals while, conversely, inhibiting different steps along the glucuronidation pathway strongly reversed RAP resistance to trametinib. For example, blocking an initial HDAC1-mediated deacetylation step with the FDA-approved drug vorinostat strongly suppressed trametinib resistance in Drosophila RAP tumours. We provide functional evidence that pairing oncogenic RAS with hyperactive WNT activity strongly elevates PI3K/AKT/GLUT signalling, which in turn directs elevated glucose and subsequent glucuronidation. Finally, we show that this mechanism of trametinib resistance is conserved in an KRAS/APC/TP53 mouse CRC tumour organoid model. Our observations demonstrate a key mechanism by which oncogenic RAS/WNT activity promotes increased drug clearance in CRC. The majority of targeted therapies are glucuronidated, and our results provide a specific path towards abrogating this resistance in clinical trials.
    DOI:  https://doi.org/10.1101/2023.12.21.572817
  8. J Gastrointest Oncol. 2023 Dec 31. 14(6): 2448-2465
       Background: Liver metastasis (LM) accounts for most colorectal cancer (CRC)-related deaths. However, how metastatic CRC cells gain the ability to survive and grow in liver remains largely unknown.
    Methods: First, we screened differentially expressed genes (DEGs) between LM and paired primary tumors (PTs) in Gene Expression Omnibus (GEO) database, and identified cytochrome P450 1B1 (CYP1B1) as the only common differential gene. Then, we verified messenger RNA (mRNA) and protein expression level in clinical specimens. After constructing stable up-regulated CYP1B1 versions of HCT116 and RKO CRC cells and stable down-regulated CYP1B1 versions of SW480 and HT29 CRC cells, cell proliferation assays, subcutaneous tumor formation, and mouse LM models were used to comprehend its function. Next, we used RNA-seq to uncover specific mechanisms of growth; cell cycle, polymerase chain reaction (PCR), western blot (WB) and GEO series (GSE) datasets were used to verify its mechanism. Last, gas chromatography tandem mass spectrometry (GC-MS/MS) was adopted to examine which fatty acids were changed.
    Results: A significantly higher level of CYP1B1 was found in LM than in PT in paired clinical CRC LM samples (P<0.05). After CYP1B1 overexpression in HCT116 and RKO cells, cell proliferation abilities in vitro and in vivo were enhanced; LM of NOD.Cg-PrkdcscidIl2rgem1Smoc (NSG) mice were enhanced. And knockdown of CYP1B1 in SW480 and HT29 cells, cell proliferation abilities in vitro and in vivo were reduced; LM of NSG mice were declined (P<0.05). RNA-seq showed 59 common genes from upregulated genes of RKO overexpression group and downregulated genes of SW480 knockdown group were enriched in cell cycle and DNA replication. Further investigation revealed CYP1B1 regulated alternation of MCM5, PCNA, and FEN1 genes, and G1/S transition in CRC cells. GC-MS/MS revealed long chain fatty acids (LCFAs) made a difference in SW480 knockdown group (P<0.05). Through adding LCFAs into SW480 and HT29 knockdown groups, cell proliferation abilities in vitro and in vivo were enhanced, and expressions of MCM5, PCNA, FEN1 were upregulated (P<0.05).
    Conclusions: CYP1B1 exerts a significant influence on LM of CRC by modulating tumor cell proliferation via "CYP1B1-LCFAs-G1/S transition". This finding suggests CYP1B1 could be a promising target for CRC LM.
    Keywords:  CYP1B1; Colorectal cancer (CRC); cell cycle; fatty acids; liver metastasis (LM)
    DOI:  https://doi.org/10.21037/jgo-23-895
  9. Cell Mol Life Sci. 2024 Jan 12. 81(1): 39
      Colorectal cancer (CRC) is characterized by a complex tumor inflammatory microenvironment, while angiogenesis and immunosuppression frequently occur concomitantly. However, the exact mechanism that controls angiogenesis and immunosuppression in CRC microenvironment remains unclear. Herein, we found that expression levels of lipid raft protein STOML2 were increased in CRC and were associated with advanced disease stage and poor survival outcomes. Intriguingly, we revealed that STOML2 is essential for CRC tumor inflammatory microenvironment, which induces angiogenesis and facilitates tumor immune escape simultaneously both in vitro and in vivo. Moreover, tumors with STOML2 overexpression showed effective response to anti-angiogenesis treatment and immunotherapy in vivo. Mechanistically, STOML2 regulates CRC proliferation, angiogenesis, and immune escape through activated NF-κB signaling pathway via binding to TRADD protein, resulting in upregulation of CCND1, VEGF, and PD-L1. Furthermore, treatment with NF-κB inhibitor dramatically reversed the ability of proliferation and angiogenesis. Clinically, we also observed a strong positive correlation between STOML2 expression and Ki67, CD31, VEGFC and PD-1 of CD8+T cell expression. Taken together, our results provided novel insights into the role of STOML2 in CRC inflammatory microenvironment, which may present a therapeutic opportunity for CRC.
    Keywords:  Angiogenesis; Colorectal cancer; Lipid rafts; NF-κB; STOML2; Tumor microenvironment
    DOI:  https://doi.org/10.1007/s00018-023-05105-y
  10. Nat Cancer. 2024 Jan 10.
      Immunosuppressive myeloid cells hinder immunotherapeutic efficacy in tumors, but the precise mechanisms remain undefined. Here, by performing single-cell RNA sequencing in colorectal cancer tissues, we found tumor-associated macrophages and granulocytic myeloid-derived suppressor cells increased most compared to their counterparts in normal tissue and displayed the highest immune-inhibitory signatures among all immunocytes. These cells exhibited significantly increased expression of immunoreceptor tyrosine-based inhibitory motif-bearing receptors, including SIRPA. Notably, Sirpa-/- mice were more resistant to tumor progression than wild-type mice. Moreover, Sirpα deficiency reprogramed the tumor microenvironment through expansion of TAM_Ccl8hi and gMDSC_H2-Q10hi subsets showing strong antitumor activity. Sirpa-/- macrophages presented strong phagocytosis and antigen presentation to enhance T cell activation and proliferation. Furthermore, Sirpa-/- macrophages facilitated T cell recruitment via Syk/Btk-dependent Ccl8 secretion. Therefore, Sirpα deficiency enhances innate and adaptive immune activation independent of expression of CD47 and Sirpα blockade could be a promising strategy to improve cancer immunotherapy efficacy.
    DOI:  https://doi.org/10.1038/s43018-023-00691-z
  11. J Clin Invest. 2024 Jan 09. pii: e171788. [Epub ahead of print]
      Choline deficiency causes disorders including hepatic abnormalities and is associated with an increased risk of multiple types of cancer(1, 2). Here, by choline free diet-associated RNA-seq analyses, we found that the tumor suppressor p53 drives the Kennedy pathway via PCYT1B to control the growth of lipid droplets (LDs) and their fueling role in tumorigenesis. Mechanistically, through upregulation of PCYT1B, p53 channeled depleted choline stores to phosphatidylcholine (PC) biosynthesis during choline starvation, thus preventing LD coalescence. Cells lacking p53 failed to complete this response to choline depletion, leading to hepatic steatosis and tumorigenesis, and these effects could be reversed by enforcing PCYT1B expression or restoring PC abundance. Furthermore, loss of p53 or defects in the Kennedy pathway increased surface localization of hormone-sensitive lipase (HSL) on LDs to release specific fatty acids that fueled tumor cells in vivo and in vitro. Thus, p53 loss leads to dysregulation of choline metabolism and LD growth, and couples perturbed LD homeostasis to tumorigenesis.
    Keywords:  Cancer; Cell Biology; Cholesterol; Tumor suppressors
    DOI:  https://doi.org/10.1172/JCI171788