Project description:In this study our aim was to document recurrent DNA copy number aberration associated breakpoints in primary tumors of colorectal cancer patients that ultimately received systemic treatment in the context of metastatic disease. Such data can be used to catalogue copy number aberration associated breakpoints and thereby affected genes. To this end, high quality arrayCGH data set of clinically well annotated colorectal cancer specimens was generated using FFPE tumor samples from patients from two phase III clinical trials, namely CAIRO and CAIRO2. arrayCGH data of colorectal cancers of patients from 2 clinical trials. 108 patients were treated with capecitabine first line, 110 patients were treated with capecitabine and irinotecan first line and 134 patients were treated with capecitabine, oxaliplatin and bevacizumab.
Project description:Despite advances in contemporary chemotherapeutic strategies, long term survival still remains elusive for patients with metastatic colorectal cancer. A better understanding of the molecular markers of drug sensitivity to match therapy with patient is needed to improve clinical outcomes. In this study, we used in vitro drug sensitivity data from the NCI-60 cell lines together with their Affymetrix microarray data to develop a gene expression signature to predict sensitivity to oxaliplatin. In order to validate our oxaliplatin sensitivity signature, Patient-Derived Colorectal Cancer Explants (PDCCEs) were developed in NOD-SCID mice from resected human colorectal tumors. Analysis of gene expression profiles found similarities between the PDCCEs and their parental human tumors, suggesting their utility to study drug sensitivity in vivo. The oxaliplatin sensitivity signature was then validated in vivo with response data from 14 PDCCEs treated with oxaliplatin and was found to have an accuracy of 92.9% (Sensitivity=87.5%; Specificity=100%). Our findings suggest that PDCCEs can be a novel source to study drug sensitivity in colorectal cancer. Furthermore, genomic-based analysis has the potential to be incorporated into future strategies to optimize individual therapy for patients with metastatic colorectal cancer. Fourty-two human tumors and murine explants of colorectal origin, both primary colon and of various metastatic sites, were processed for total RNA. The samples included RNA from 14 patient samples in addition to RNA from Patient-Derived Colorectal Cancer Explant (PDCCEs) generated from these 14 patient samples. The PDCCEs were processed as fresh frozen whole tumor in addition to formalin-fixed paraffin-embedded (FFPE) tumors.
Project description:Response to drug therapy in individual colorectal cancer (CRC) patients is associated with tumor biology. Here we describe the genomic landscape of tumor samples of a homogeneous well-annotated series of patients with metastatic CRC of two phase III clinical trials, CAIRO and CAIRO2. DNA copy number aberrations of 349 patients are determined. Within three treatment arms, 194 chromosomal sub-regions are associated with progression free survival PFS (uncorrected single-test p-values < 0.005). These sub-regions are filtered for effect on mRNA expression, using an independent data set from The Cancer Genome Atlas (TCGA) which returned 171 genes. Three chromosomal regions are associated with a significant difference in PFS between treatment arms with or without irinotecan. One of these regions, 6q16.1-q21, correlates in vitro with sensitivity to SN-38, the active metabolite of irinotecan. This genomic landscape of metastatic CRC reveals a number of DNA copy number aberrations associated with response to drug therapy. aCGH data of colorectal cancers of patients from 2 clinical trials (CAIRO, CAIRO2). 105 patients were treated with capecitabine first line (CAIRO arm A), 111 patients were treated with capecitabine and irinotecan first line (CAIRO arm B), and 133 patients were treated with capecitabine, oxaliplatin and bevacizumab (CAIRO2 arm A).
Project description:Using whole genome tumor gene expression profiling in patients treated for metastatic colorectal cancer, we attempted to define a signature able to discriminate between responders and non-responders to first-line chemotherapy.
Project description:Metastatic colorectal cancer (mCRC) is associated with multiple somatic copy number alterations (SCNAs). We analyzed SCNAs to estimate overall survival (OS) and progression free suvival (PFS) for mCRC patients treated with bevacizumab in combination with oxaliplatin or irinotecan.
Project description:To measure global gene expression in primary metastatic colorectal cancer patients who have undergone fluorouracil, leucovorin and oxaliplatin (FOLFOX) chemotherapy and screen valuable biomarkers to predict the effects of chemotherapy. Samples from primary metastatic colorectal cancer patients were collected. The effects of chemotherapy were evaluated.
Project description:Despite advances in contemporary chemotherapeutic strategies, long term survival still remains elusive for patients with metastatic colorectal cancer. A better understanding of the molecular markers of drug sensitivity to match therapy with patient is needed to improve clinical outcomes. In this study, we used in vitro drug sensitivity data from the NCI-60 cell lines together with their Affymetrix microarray data to develop a gene expression signature to predict sensitivity to oxaliplatin. In order to validate our oxaliplatin sensitivity signature, Patient-Derived Colorectal Cancer Explants (PDCCEs) were developed in NOD-SCID mice from resected human colorectal tumors. Analysis of gene expression profiles found similarities between the PDCCEs and their parental human tumors, suggesting their utility to study drug sensitivity in vivo. The oxaliplatin sensitivity signature was then validated in vivo with response data from 14 PDCCEs treated with oxaliplatin and was found to have an accuracy of 92.9% (Sensitivity=87.5%; Specificity=100%). Our findings suggest that PDCCEs can be a novel source to study drug sensitivity in colorectal cancer. Furthermore, genomic-based analysis has the potential to be incorporated into future strategies to optimize individual therapy for patients with metastatic colorectal cancer.
Project description:We report that previously described molecular subtypes of colorectal cancer are associated with the response to therapy in patients with metastatic disease. We also identified a patient population with high FOLFIRI sensitivity, as indicated by their 2.7-fold longer overall survival when treated with FOLFIRI, as first-line regimen, instead of FOLFOX. Our results demonstrate the interest of molecular classifications to develop tailored therapies for patients with metastatic colorectal cancer.
Project description:We report that previously described molecular subtypes of colorectal cancer are associated with the response to therapy in patients with metastatic disease. We also identified a patient population with high FOLFIRI sensitivity, as indicated by their 2.7-fold longer overall survival when treated with FOLFIRI, as first-line regimen, instead of FOLFOX. Our results demonstrate the interest of molecular classifications to develop tailored therapies for patients with metastatic colorectal cancer.
Project description:Almost half of the patients with advanced colorectal cancer (CRC) are resistant to oxaliplatin based therapy, the first line treatment for CRC. Therefore, predicting and understanding oxaliplatin resistance is important to improve CRC patient survival. Investigated here is the use of proteomic folding stability measurements to differentiate oxaliplatin resistant and sensitive CRCs using patient-derived CRC cell lines and patient-derived xenografts (PDXs). Three protein stability profiling techniques (including the Stability of Proteins from Rates of Oxidation (SPROX), the Thermal Protein Profiling (TPP), and Limited Proteolysis (LiP) approaches) were employed to identify differentially stabilized proteins in 6 patient-derived CRC cell lines with different oxaliplatin sensitivities and 8 CRC PDXs derived from 2 of the patient derived cell lines with different oxaliplatin sensitivity. A total of 23 proteins were found in at least 2 techniques to be differentially stabilized in both the cell line and PDX studies of oxaliplatin resistance. These 23 differentially stabilized proteins included 9 proteins that have been previously connected to cancer chemoresistance. Over-representation analysis (ORA) of all the differentially stabilized proteins identified here, revealed novel pathways related to oxaliplatin resistance. Compared to conventional protein expression level analyses, which were also performed on the cell lines and PDXs, the stability profiling techniques identified novel proteins and pathways and provided new insight on the molecular basis of oxaliplatin resistance. Our results suggest that protein stability profiling techniques are complementary to expression level analyses for identifying biomarkers and understanding molecular mechanisms associated with oxaliplatin chemoresistance in CRC and disease phenotypes in general.