Abstract 960: RNF43 G659fs is an oncogenic mutation in colorectal cancer and sensitizes tumor cells to PI3K/mTOR inhibition

Circulating tumor cells (CTCs) are cells shed from the primary tumor into the bloodstream. While many studies on solid tumor cells exist, data on CTCs are scarce. The mortality of cancer is mostly associated with metastasis and recent research identified CTCs as initiators of metastasis. The PI3K/AKT/mTOR signaling pathway is an intracellular pathway that regulates essential functions including protein biosynthesis, cell growth, cell cycle control, survival and migration. Importantly, activating oncogenic mutations and amplifications in this pathway are frequently observed in a wide variety of cancer entities, underlining the significance of this signaling pathway. In this study, we analyzed the functional role of the PI3K/AKT/mTOR signaling pathway in the CTC-MCC-41 line, derived from a patient with metastatic colorectal cancer. One striking finding in our study was the strong sensitivity of this CTC line against AKT inhibition using MK2206 and mTOR inhibition using RAD001 within the nanomolar range. This suggests that therapies targeting AKT and mTOR could have been beneficial for the patient from which the CTC line was isolated. Additionally, a dual targeting approach of AKT/mTOR inside the PI3K/AKT/mTOR signaling pathway in the colorectal CTCs showed synergistic effects in vitro. Depending on the phenotypical behavior of CTC-MCC-41 in cell culture (adherent vs. suspension), we identified altered phosphorylation levels inside the PI3K/AKT/mTOR pathway. We observed a downregulation of the PI3K/AKT/mTOR signaling pathway, but not of the RAS/RAF/MAPK pathway, in CTCs growing in suspension in comparison to adherent CTCs. Our results highlight distinct functions of AKT isoforms in CTC-MCC-41 cells with respect to cell proliferation. Knockdown of AKT1 and AKT2 leads to significantly impaired proliferation of CTC-MCC-41 cells in vitro. Therefore, our data demonstrate that the PI3K/AKT/mTOR signaling pathway plays a key role in the proliferation of CTC-MCC-41.

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Faculty Opinions recommendation of Isolated tumor cells in regional lymph nodes as relapse predictors in stage I and II colorectal cancer.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.14264074.15779078 ◽

2012 ◽

Author(s):

Daniel Vorobiof ◽

Keo Tabane

Keyword(s):

Colorectal Cancer ◽

Lymph Nodes ◽

Tumor Cells ◽

Stage I ◽

Isolated Tumor Cells ◽

Regional Lymph Nodes

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The Caspase-1/IL-18 Axis of the Inflammasome in Tumor Cells: A Modulator of the Th1/Tc1 Response of Tumor-Infiltrating T Lymphocytes in Colorectal Cancer

Cancers ◽

10.3390/cancers13020189 ◽

2021 ◽

Vol 13 (2) ◽

pp. 189

Author(s):

Linda Bilonda Mutala ◽

Cécile Deleine ◽

Matilde Karakachoff ◽

Delphine Dansette ◽

Kathleen Ducoin ◽

...

Keyword(s):

Colorectal Cancer ◽

T Lymphocytes ◽

Tumor Cells ◽

Ex Vivo ◽

Explant Culture ◽

T Cell Response ◽

Mrna Levels ◽

Innate And Adaptive Immunity ◽

Caspase 1 ◽

Culture Model

In colorectal cancer (CRC), a high density of T lymphocytes represents a strong prognostic marker in subtypes of CRC. Optimized immunotherapy strategies to boost this T-cell response are still needed. A good candidate is the inflammasome pathway, an emerging player in cancer immunology that bridges innate and adaptive immunity. Its effector protein caspase-1 matures IL-18 that can promote a T-helper/cytotoxic (Th1/Tc1) response. It is still unknown whether tumor cells from CRC possess a functional caspase-1/IL-18 axis that could modulate the Th1/Tc1 response. We used two independent cohorts of CRC patients to assess IL-18 and caspase-1 expression by tumor cells in relation to the density of TILs and the microsatellite status of CRC. Functional and multiparametric approaches at the protein and mRNA levels were performed on an ex vivo CRC explant culture model. We show that, in the majority of CRCs, tumor cells display an activated and functional caspase-1/IL-18 axis that contributes to drive a Th1/Tc1 response elicited by TILs expressing IL-18Rα. Furthermore, unsupervised clustering identified three clusters of CRCs according to the caspase-1/IL-18/TIL density/interferon gamma (IFNγ) axis and microsatellite status. Together, our results strongly suggest that targeting the caspase-1/IL-18 axis can improve the anti-tumor immune response in subgroups of CRC.

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Epithelial-Mesenchymal Transition and MicroRNAs in Colorectal Cancer Chemoresistance to FOLFOX

Pharmaceutics ◽

10.3390/pharmaceutics13010075 ◽

2021 ◽

Vol 13 (1) ◽

pp. 75

Author(s):

Paula I. Escalante ◽

Luis A. Quiñones ◽

Héctor R. Contreras

Keyword(s):

Colorectal Cancer ◽

Tumor Cells ◽

Methylenetetrahydrofolate Reductase ◽

Epithelial Mesenchymal Transition ◽

Late Onset ◽

Dihydropyrimidine Dehydrogenase ◽

Acquired Resistance ◽

Potential Effect ◽

Mesenchymal Transition ◽

Folfox Chemotherapy

The FOLFOX scheme, based on the association of 5-fluorouracil and oxaliplatin, is the most frequently indicated chemotherapy scheme for patients diagnosed with metastatic colorectal cancer. Nevertheless, development of chemoresistance is one of the major challenges associated with this disease. It has been reported that epithelial-mesenchymal transition (EMT) is implicated in microRNA-driven modulation of tumor cells response to 5-fluorouracil and oxaliplatin. Moreover, from pharmacogenomic research, it is known that overexpression of genes encoding dihydropyrimidine dehydrogenase (DPYD), thymidylate synthase (TYMS), methylenetetrahydrofolate reductase (MTHFR), the DNA repair enzymes ERCC1, ERCC2, and XRCC1, and the phase 2 enzyme GSTP1 impair the response to FOLFOX. It has been observed that EMT is associated with overexpression of DPYD, TYMS, ERCC1, and GSTP1. In this review, we investigated the role of miRNAs as EMT promotors in tumor cells, and its potential effect on the upregulation of DPYD, TYMS, MTHFR, ERCC1, ERCC2, XRCC1, and GSTP1 expression, which would lead to resistance of CRC tumor cells to 5-fluorouracil and oxaliplatin. This constitutes a potential mechanism of epigenetic regulation involved in late-onset of acquired resistance in mCRC patients under FOLFOX chemotherapy. Expression of these biomarker microRNAs could serve as tools for personalized medicine, and as potential therapeutic targets in the future.

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Unexpected tumor reduction in metastatic colorectal cancer patients during SARS-Cov-2 infection: effect of ACE-2 expression on tumor cells or molecular mimicry phenomena? Two not mutually exclusive hypotheses

Therapeutic Advances in Medical Oncology ◽

10.1177/17588359211027825 ◽

2021 ◽

Vol 13 ◽

pp. 175883592110278

Author(s):

Francesco Cappello ◽

Stefano Burgio ◽

Everly Conway de Macario ◽

Alberto J. L. Macario

Keyword(s):

Colorectal Cancer ◽

Metastatic Colorectal Cancer ◽

Cancer Patients ◽

Tumor Cells ◽

Molecular Mimicry ◽

Tumor Reduction ◽

Colorectal Cancer Patients

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Interleukin-11-expressing fibroblasts have a unique gene signature correlated with poor prognosis of colorectal cancer

Nature Communications ◽

10.1038/s41467-021-22450-3 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Takashi Nishina ◽

Yutaka Deguchi ◽

Daisuke Ohshima ◽

Wakami Takeda ◽

Masato Ohtsuka ◽

...

Keyword(s):

Colorectal Cancer ◽

Tumor Cells ◽

Human Cancer ◽

Tumor Development ◽

Gene Signature ◽

Free Survival ◽

Expression Of Genes ◽

Reporter Mice ◽

Interleukin 11

AbstractInterleukin (IL)-11 is a member of the IL-6 family of cytokines and is involved in multiple cellular responses, including tumor development. However, the origin and functions of IL-11-producing (IL-11+) cells are not fully understood. To characterize IL-11+ cells in vivo, we generate Il11 reporter mice. IL-11+ cells appear in the colon in murine tumor and acute colitis models. Il11ra1 or Il11 deletion attenuates the development of colitis-associated colorectal cancer. IL-11+ cells express fibroblast markers and genes associated with cell proliferation and tissue repair. IL-11 induces the activation of colonic fibroblasts and epithelial cells through phosphorylation of STAT3. Human cancer database analysis reveals that the expression of genes enriched in IL-11+ fibroblasts is elevated in human colorectal cancer and correlated with reduced recurrence-free survival. IL-11+ fibroblasts activate both tumor cells and fibroblasts via secretion of IL-11, thereby constituting a feed-forward loop between tumor cells and fibroblasts in the tumor microenvironment.

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TIGIT Induces (CD3+) T Cell Dysfunction by Inhibiting Glucose Metabolism and its Reversal by TIGIT and/or PD-1 Blockade in Colorectal Cancer

10.21203/rs.3.rs-641407/v1 ◽

2021 ◽

Author(s):

qi shao ◽

Lei Wang ◽

maoling yuan ◽

Xiaohong Jin ◽

changping wu

Keyword(s):

Colorectal Cancer ◽

T Cells ◽

T Cell ◽

Glucose Metabolism ◽

Tumor Growth ◽

Tumor Cells ◽

Peripheral Blood ◽

Cancer Tissue ◽

Cell Dysfunction ◽

T Cell Dysfunction

Abstract Background: T-cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain (TIGIT) is an immunosuppressive receptor expressed on the surface of immune cells, suppressing immune responses by activating the intracellular negative regulatory signals. TIGIT plays an important role in the pathogenesis of various tumors, but its immune escape in colorectal cancer remains unclear.Methods: In this study, TIGIT expression in the peripheral blood and tissue microarrays was detected flow cytometry and immunofluorescence and its relationship with prognosis was evaluated. The proliferation and cytokines of TIGIT+ T cells were measured. Glucose metabolism and key enzymes were detected by qPCR or western blot. After establishing the co-cultured system and xenotransplant models, TIGIT antibody alone or combined with PD-1 antibody was blocked to observe the tumor growth.Results: We found that the proportion of CD3+TIGIT+ T cells was increased in peripheral blood and cancer tissue in colorectal cancer patients when compared with the healthy donors. These cells exhibited functional defects, low proliferative activity, impaired cytokine production and reduced glucose metabolism. A strong association was also observed between the elevated TIGIT expression and poor prognosis. In the in vitro co-culture assays of T cells and tumor cells, the suppressed glucose metabolic activity of T cells was reversed by TIGIT blockade. In addition, this blockade induced the apoptosis and reduced G2/M transit in tumor cells. The antitumor efficacy of TIGIT Ab therapy was further demonstrated in a human colorectal xenograft mice model while co-blockers of TIGIT and PD-1 exhibited synergistic suppressing effects on tumor growth.Conclusions: It is suggest that while TIGIT induces CD3+ T cell dysfunction in colorectal cancer, co-targeting TIGIT and PD-1 can lead to an effective antitumor response and may serve as a novel therapeutic strategy for colorectal patients.

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