Project description:Comparison the mRNA expression profiles of 101 CRC tissues to those from matched 35 non-neoplastic colon mucosal tissues from patients with stage III CRCs treated with FOLFOX adjuvant chemotherapy in each molecular subtype. Gene expression–based subtyping is widely accepted as a relevant source of disease stratification. Results provide important information of molecular marker genes for molecular classification.
Project description:Colorectal cancer (CRC) has one of the highest worldwide incidences and mortality rates. Compared to surgery alone, adjuvant 5-Fluorouracil (5FU)-based chemotherapy improves 5-year overall survival (OS) in only 3-4% of stage II and 15-20% of stage III patients in unselected populations. Significant advances have been made in the molecular stratification of CRC, with the emerging Consensus Molecular Subtype (CMS) and Colorectal Cancer Intrinsic Signature (CRIS) transcriptomics-based classification systems; however, the therapeutic impact of molecular stratification has so far been limited. In an effort to identify subgroups of patients benefitting from chemotherapy, we assessed which CMS and CRIS subgroups of stage II and III CRC benefitted from adjuvant 5FU-based chemotherapy using in-house and published datasets.
Project description:Relapse and metastatic progression is a frequent event in colorectal cancer patients detected at early stages. The risk of recurrence requires the development of new biomarkers to correctly predict biological behavior of early stage II and stage III patients and their response to adjuvant chemotherapy. Here, we combined the proteomic quantification of secreted proteins involved in metastasis with a transcriptional analysis to develop a risk score algorithm based on the expression of six genes (SEC6). The SEC6 signature was predictive of survival and recurrence for stage II and III patients in four different datasets including a total of 1534 patients and was also associated with deficient mismatch repair, CpG-island methylator positive status and BRAF mutation. SEC6 was also predictive of beneficial or detrimental effects from 5-Fluorouracil-containing regimes and the improved response to more aggressive chemotherapies based on FOLFOX and FOLFIRI. In summary, the SEC6 risk-score algorithm may constitute a new tool for decision-making in colorectal cancer management.
Project description:Colorectal cancer is one of the most common cancers in the world. Histological staging is efficient but combination with molecular markers may improve tumors classification. Gene expression profiles have been defined as prognosis predictors among stage II and III tumors but their implementation in medical practice remains controversial. Stage-II tumors have been recognized as a heterogeneous group and high-risk morphologic features have been retained as justifying adjuvant chemotherapy. We propose here the investigation of clinical features and expression profiles from stage II and stage III colon carcinomas without DNA mismatch repair defect. A series of 130 colon cancer samples was retained. Expression profiles were established on oligonucleotide microarrays and processed in the R/Bioconductor environment. Hierarchical then supervised analyses were successively performed applying the data-sampling approach. A molecular signature of seven genes was found to cluster stage III tumors with an adjusted p-values lower than 10^-10. A subgroup of stage-II tumors aggregated this cluster in both series. No correlation was found between with the disease severity but the function of the discriminating genes suggests that tumors have been classified according to their putative response to adjuvant targeted or classic therapies. Further pharmacogenetic studies might document this observation. Expression profile of stage-II colon carcinomas distinguishes two patterns of tumors based on a 7-gene signature. One pattern is very similar to that of stage-III tumors and the corresponding tumors aggregate into a single cluster. Genes function suggests possible tumor determinism in drug response more than in prognosis evolution.
Project description:The aim of our study was to identify a microRNA signature to predict the recurrence in stage II & III CRC patients who were treated with FOLFOX-based adjuvant chemotherapy after curative resection of tumors. We performed small RNA sequencing in 71 FFPE surgical specimens, and discovered differentially expressed microRNAs in patients who developed recurrence. Thereafter, selected microRNA biomarkers were validated in independent cohort using qRT-PCR assay.
Project description:In this study, we evaluated the added value of CMS in predicting both prognosis and benefit of adjuvant chemotherapy in stage III CC patients.
Project description:Colorectal cancer is one of the most common cancers in the world. Histological staging is efficient but combination with molecular markers may improve tumors classification. Gene expression profiles have been defined as prognosis predictors among stage II and III tumors but their implementation in medical practice remains controversial. Stage-II tumors have been recognized as a heterogeneous group and high-risk morphologic features have been retained as justifying adjuvant chemotherapy. We propose here the investigation of clinical features and expression profiles from stage II and stage III colon carcinomas without DNA mismatch repair defect. A series of 130 colon cancer samples was retained. Expression profiles were established on oligonucleotide microarrays and processed in the R/Bioconductor environment. Hierarchical then supervised analyses were successively performed applying the data-sampling approach. A molecular signature of seven genes was found to cluster stage III tumors with an adjusted p-values lower than 10^-10. A subgroup of stage-II tumors aggregated this cluster in both series. No correlation was found between with the disease severity but the function of the discriminating genes suggests that tumors have been classified according to their putative response to adjuvant targeted or classic therapies. Further pharmacogenetic studies might document this observation.
Project description:To search for potential miRNAs associated with prognosis in colorectal carcinoma, miRNA expression profiles were analyzed in patients with stage III colorectal carcinoma. miRNA expression levels were compared between long and short time survival after surgery with standard chemotherapy.
Project description:SCN5A was reported to promote proliferation and invasiveness potential in colorectal cancer, yet the mechanism was not clarified, and little was known about its association with chemosensitivity to 5-fluorouracil. In the current study, elevated SCN5A expression were associated with poor prognosis and metastasis in colorectal cancers, whereas stage II-III patients with up-regulated SCN5A expression were more likely to benefit from 5-fluorouracil-based adjuvant chemotherapy. SCN5A could promote proliferation and invasiveness potential through regulating cell cycle and epithelial-mesenchymal transition in colorectal cancer cells. Furthermore, SCN5A regulated Ras signaling by stabilizing KRas-calmodulin complex through Ca2+ influx. Apart from that, under 5-fluorouracil treatment, SCN5A promoted calmodulin-dependent apoptosis in colorectal cancers.
Project description:Purpose: The DNA Damage Immune Response (DDIR) assay was developed in breast cancer (BC) based on biology associated with deficiencies in homologous recombination and Fanconi Anemia (HR/FA) pathways. A positive DDIR call identifies patients likely to respond to platinum-based chemotherapies in breast and oesophageal cancers. In colorectal cancer (CRC) there is currently no biomarker to predict response to oxaliplatin. We tested the ability of the DDIR assay to predict response to oxaliplatin-based chemotherapy in CRC and characterised the biology in DDIR-positive CRC. Methods: Samples and clinical data were assessed according to DDIR status from patients who received either 5FU or FOLFOX within the FOCUS trial (n=361, stage 4), or neo-adjuvant FOLFOX in the FOxTROT trial (n=97, stage 2/3). Whole transcriptome, mutation and immunohistochemistry data of these samples were used to interrogate the biology of DDIR in CRC. Results: Contrary to our hypothesis, DDIR negative patients displayed a trend towards improved outcome for oxaliplatin-based chemotherapy compared to DDIR positive patients. DDIR positivity was associated with Microsatellite Instability (MSI) and Colorectal Molecular Subtype 1 (CMS1). Refinement of the DDIR signature, based on overlapping interferon-related chemokine signalling associated with DDIR positivity across CRC and BC cohorts, further confirmed that the DDIR assay did not have predictive value for oxaliplatin-based chemotherapy in CRC. Conclusions: DDIR positivity does not predict improved response following oxaliplatin treatment in CRC. However, data presented here suggests the potential of the DDIR assay in identifying immune-rich tumours that may benefit from immune checkpoint blockade, beyond current use of MSI status.