Search bioRxiv⌕ Search

bioRxiv · 10.1101/2022.09.07.506931

PAMR1 negatively impacts cell proliferation and migration of Human Colon Cancer HT29 Cell Line

Abstract

Colorectal cancer (CRC) is becoming one of the most prevalent cancers worldwide. Among cancers, it ranks the third place in terms of incidence and the second in terms of mortality. Even though immunological test allows fast and easy diagnostic method, there is no specific and reliable methods for early detection of CRC. Despite different treatments, high risk of re-occurrence is associated with advanced and metastatic CRC stages. An exhaustive knowledge on specific biomarkers or molecular actors involved in CRC could help to eradicate tumors or limit cancer recurrence. In this study, we focused on PAMR1 (Peptidase Domain Containing Associated with Muscle Regeneration 1), which is already considered as a tumor suppressor in breast and cervical cancers. In silico analysis of RNASeq data showed that PAMR1 was significantly downregulated in CRC tissues compared to their adjacent normal ones, as well as in cervical cancer. Our analysis showed that this downregulation, probably due to promoter hypermethylation, such as in breast cancer tissues, appeared in the four cancer stages as early as the first stage. In consistency with in silico analyses, the expression of PAMR1 was found to be lower at the transcript and protein levels in CRC tissue samples compared to normal ones, as well as in different CRC cell lines (HCT116, HT29, and SW620) compared to normal colon cell line (CCD841CoN). To understand the role of PAMR1 in CRC cancer, recombinant purified PAMR1 or concentrated secretome from CHO overexpressing PAMR1 were used to exogenously treat CRC cell lines with a focus on HT-29 cells as well as Hela cervical cancer cell line known to be sensitive to PAMR1. Transient or stable transfections were also performed to determine the impact of PAMR1 overexpression in HT29 and/or HeLa cells. In this study, we finally showed that presence of PAMR1 could reduce both cell proliferation and cell migration with a positive correlation between these biological effects and PAMR1s quantity. This implies that PAMR1 expresses anti-proliferative and anti-migrative effects in CRC. Further studies to be done in order to confirm the tumor suppressive role of PAMR1 in CRC.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Haymour, L., Chaunavel, A., Diab-Assaf, M., Maftah, A., Legardinier, S.. 2022-09-08. PAMR1 negatively impacts cell proliferation and migration of Human Colon Cancer HT29 Cell Line. https://doi.org/10.1101/2022.09.07.506931

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

Tissue resident CD4+ memory T-cells mark response to immune checkpoint inhibition in high-grade glioma

Background: Immune checkpoint inhibitors (ICI) are efficacious in many solid tumors, but response in glioma is restricted to a small subgroup. The determinants of response and resistance to ICI remain poorly understood. Methods: Here we exploit a syngeneic hypermutated high-grade glioma model with dichotomous response to combined PD-1 and CTLA-4 inhibition to unravel determinants of tumor-infiltrating T-cells driving response. Tumor-infiltrating T-cells from ICI-responsive and non-responsive tumors were analyzed by single-cell RNA and T-cell receptor sequencing and tumor-reactive T-cell receptor clonotypes were functionally validated to characterize their transcriptional phenotypes. We verify our findings in IDH1 wildtype glioblastoma patients treated with neoadjuvant pembrolizumab. Results: ICI response was associated with intratumoral clonal expansion of tumor-reactive cytotoxic T-cells and increased infiltration of CXCR6+ CD4+ tissue resident memory T-cells (Trm). CD4 stem-like memory T-cells in responding tumors demonstrated elevated interferon responses, following trajectories toward clonally expanded Trm, versus trajectories toward exhaustion in non-responsive tumors. In responsive tumors, CD4+ Trm interacted with infiltrating CXCR3+ tumor-reactive and clonally expanded, yet transcriptionally versatile cytotoxic T-cells. Probing the post neoadjuvant ICI high-grade glioma patient tissue dataset, we confirmed increased CXCR6 expression in CD4+ T cells and the association of CD4+ Trm with prolonged overall survival. Conclusion: These findings identify CD4 tissue-resident memory T-cells as determinants of ICI response in IDH1 wildtype high-grade glioma and warrant their further investigation to improve immunotherapy outcomes.

cancer biology↗

Circadian gene-network distortion in high-risk neuroblastoma across multiple biological reference contexts

Background: The circadian clock regulates cellular homeostasis, and its disruption has been implicated in aggressive neuroblastoma, particularly in tumours harbouring MYCN- amplification. However, it remains unclear whether alterations are restricted to individual clock genes or extend to circadian gene network coordination. We therefore examined circadian clock network disruption in adverse neuroblastoma across multiple biological contexts. Methods: We estimated circadian gene network dysregulation using Delta-CCD in tumours from two neuroblastoma cohorts (SEQC n=498 and Kocak n=649), comparing clinical features associated with outcome across canonical, adrenal-tissue matched, and developmental references. Robustness was assessed by cross-cohort meta-analysis and leave-one-gene-out analyses. Cox proportional hazards models adjusted for clinical covariates assessed association between individual clock gene expression patient outcome. Results: Delta-CCD was highest in tumours classified as high-risk (study-specific definition) across reference contexts in both cohorts. MYCN-amplified tumours showed a more reference-dependent pattern, strongest in adrenal context, while stage 4 tumours showed a similar but weaker pattern. Additional analyses supported the high-risk signal as a distributed network-level alteration rather than a single-gene phenomenon. Conclusions: High-risk neuroblastoma is characterised by robust disruption of coordinated clock gene network organisation across canonical and tissue-matched references, extending beyond individual clock genes. The extent of circadian dysregulation depends on the reference state used.

cancer biology↗

BAP1 loss and PRAME expression converge to remodel the tumor-immune ecosystem during uveal melanoma progression

Uveal melanoma (UM) is characterized by a small number of recurrent genetic alterations that determine metastatic propensity. BAP1 loss and PRAME expression define the dominant prognostic axes in UM, yet how they promote malignant progression remains unclear. We profiled 190,535 cells from normal uvea, uveal nevus, primary and metastatic UM using single-cell transcriptomics, T cell receptor sequencing, spatial transcriptomics and isogenic perturbation models. Normal melanocytes, nevus cells and UM cells formed a transcriptional continuum marked by loss of differentiation and emergence of neural crest-like, stress-responsive, hypoxic-glycolytic and immune-interacting states. BAP1 loss and PRAME expression imposed distinct but convergent immunoregulatory programs, inducing interferon and TNF-NFkB signaling and MHC-I expression, with HLA-E showing the strongest response. These alterations were accompanied by macrophage and CD8+ T cell remodeling. PRAME-enriched tumor regions formed spatially organized niches enriched for macrophages and plasma cells. These findings define BAP1 loss and PRAME expression as distinct but convergent axes of tumor-immune coevolution and nominate HLA-E as a candidate mediator of immune resistance.

cancer biology↗