Project description:Molecular characterization of 7 peritoneally-metastatic gastric cancer cell lines and primary cancer cells established from a patients’ ascites. We performed comprehensive transcriptome analyses using microarrays of our established gastric cancer cell lines and primary cancer cells.
Project description:Establishment and molecular characterization of 49 peritoneally-metastatic gastric cancer cell lines from 18 patients’ ascites. We performed comprehensive transcriptome analyses using microarrays of our established gastric cancer cell lines.
Project description:Genome-wide mRNA expression profiles of 31 primary gastric tumors from the UK patient cohort. Gastric cancer (GC) is the second leading cause of global cancer mortality, with individual gastric tumors displaying significant heterogeneity in their deregulation of various oncogenic pathways. We aim to identify major oncogenic pathways in GC that robustly impact patient survival and treatment response. We used an in silico strategy based on gene expression signatures and connectivity analytics to map patterns of oncogenic pathway activation in 25 unique GC cell lines, and in 301 primary gastric cancers from three independent patient cohorts. Of 11 oncogenic pathways previously implicated in GC, we identified three predominant pathways (proliferation/stem cell, NF-kB, and Wnt/b-catenin) deregulated in the majority (>70%) of gastric tumors. Using a variety of proliferative, Wnt, and NF-kB-related assays, we experimentally validated the pathway predictions in multiple GC cell lines showing similar pathway activation patterns in vitro. Patients stratified at the level of individual pathways did not exhibit consistent differences in clinical outcome. However, patients grouped by oncogenic pathway combinations demonstrated robust and significant survival differences (e.g., high proliferation/high NF-kB vs. low proliferation/low NF-kB), suggesting that tumor behavior in GC is likely influenced by the combined effects of multiple oncogenic pathways. Our results demonstrate that GCs can be successfully taxonomized by oncogenic pathway activity into biologically and clinically relevant subgroups. Keywords: gastric cancer, cell culture
Project description:Regions of recurrent genomic amplification and deletion are frequently observed in primary gastric cancers (GC). However, identifying specific oncogenes and tumor suppressor genes within these regions can be challenging, as they often cover tens to hundreds of genes. Here, we combined high-resolution array-based comparative genomic hybridization (aCGH) with gene expression profiling to target genes lying within focal high-level amplifications in GC cell lines, and identified RAB23 as an amplified and overexpressed Chr 6p11p12 gene in Hs746T cells. High RAB23 protein expression was also observed in some lines lacking RAB23 amplification, suggesting additional mechanisms besides gene amplification for up-regulating RAB23. siRNA silencing of RAB23 reduced the invasive potential of both amplified and nonamplified GC cell lines. RAB23 gene amplifications were observed in 13% of primary gastric carcinomas. In two independent patient cohorts, RAB23 transcript and protein expression was significantly associated with diffuse-type gastric cancer (dGC) compared to intestinal-type gastric cancer (iGC), providing further evidence that dGC and iGC likely represent two molecularly distinct tumor types. Our study demonstrates that investigating focal chromosomal amplifications by combining highresolution aCGH with expression profiling is a powerful general strategy for identifying novel cancer genes in recurrent regions of chromosomal aberration. Keywords: gastric cancer cell lines, comparative genomic hybridization, gene expression profiling Affy 100K SNP profiling and 32K BAC Array profiling for 7 Gastric Cancer Cell Lines
Project description:Regions of recurrent genomic amplification and deletion are frequently observed in primary gastric cancers (GC). However, identifying specific oncogenes and tumor suppressor genes within these regions can be challenging, as they often cover tens to hundreds of genes. Here, we combined high-resolution array-based comparative genomic hybridization (aCGH) with gene expression profiling to target genes lying within focal high-level amplifications in GC cell lines, and identified RAB23 as an amplified and overexpressed Chr 6p11p12 gene in Hs746T cells. High RAB23 protein expression was also observed in some lines lacking RAB23 amplification, suggesting additional mechanisms besides gene amplification for up-regulating RAB23. siRNA silencing of RAB23 reduced the invasive potential of both amplified and nonamplified GC cell lines. RAB23 gene amplifications were observed in 13% of primary gastric carcinomas. In two independent patient cohorts, RAB23 transcript and protein expression was significantly associated with diffuse-type gastric cancer (dGC) compared to intestinal-type gastric cancer (iGC), providing further evidence that dGC and iGC likely represent two molecularly distinct tumor types. Our study demonstrates that investigating focal chromosomal amplifications by combining highresolution aCGH with expression profiling is a powerful general strategy for identifying novel cancer genes in recurrent regions of chromosomal aberration. Keywords: gastric cancer cell lines, comparative genomic hybridization, gene expression profiling
Project description:YTN2 and YTN16 cell lines are subclones established from chemically induced gastric cancer (Yamamoto M et al. Cancer Science 2018). When inoculated to normal C57BL/6 mice, YTN2 spontaneously regresses , while YTN16 grows progressively. To compare expression profiles of these cell lines, we examined microarray analysis.
Project description:Genome-wide mRNA expression profiles of 31 primary gastric tumors from the UK patient cohort. Gastric cancer (GC) is the second leading cause of global cancer mortality, with individual gastric tumors displaying significant heterogeneity in their deregulation of various oncogenic pathways. We aim to identify major oncogenic pathways in GC that robustly impact patient survival and treatment response. We used an in silico strategy based on gene expression signatures and connectivity analytics to map patterns of oncogenic pathway activation in 25 unique GC cell lines, and in 301 primary gastric cancers from three independent patient cohorts. Of 11 oncogenic pathways previously implicated in GC, we identified three predominant pathways (proliferation/stem cell, NF-kB, and Wnt/b-catenin) deregulated in the majority (>70%) of gastric tumors. Using a variety of proliferative, Wnt, and NF-kB-related assays, we experimentally validated the pathway predictions in multiple GC cell lines showing similar pathway activation patterns in vitro. Patients stratified at the level of individual pathways did not exhibit consistent differences in clinical outcome. However, patients grouped by oncogenic pathway combinations demonstrated robust and significant survival differences (e.g., high proliferation/high NF-kB vs. low proliferation/low NF-kB), suggesting that tumor behavior in GC is likely influenced by the combined effects of multiple oncogenic pathways. Our results demonstrate that GCs can be successfully taxonomized by oncogenic pathway activity into biologically and clinically relevant subgroups. Experiment Overall Design: Profiling of 31 primary gastric tumors on Affymetrix GeneChip Human Genome U133 Array Set HG-U133A. All tumors were collected with approvals from the St James's University Hospital, United Kingdom and the Research Ethics Review Committee.
Project description:Genome wide DNA methylation profiling of gastric cancer cell lines. The Illumina Goldengate DNA methylation Beadchip was used to obtain DNA methylation profiles across 1,505 CpG CpGs in 20 gastric cancer cell lines.