Project description:We used microarrays to identify the gene expression accompanied with growth arrest caused by the transduction of CDX1 or CDX2. Ectopic expression of CDXs causes intestinal metaplasia, which is thought to be precancerous legion of gastric cancer. On the contrary, there were some studies reported that CDX2 positive gastric cancers showed better prognosis or tumor suppressive activity. To evaluate the effect of exogenous CDX expression in gastric cancer cells, we transducted CDX1 or CDX2 in two CDX negative expression cell lines, MKN7 and TMK1.
Project description:In this study, we investigated amplifications and deletions of 49 gastric cancer cell lines by 244k oligonucleotide-based array comparative genomic hybridization.
Project description:Transcriptional profiling of comparing control and GAPLINC knocking-down human gastric cancer cell lines. Goal was to determine the different gene expression between control and GAPLINC knocking-down human 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 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:Transcriptional profiling of comparing control and GAPLINC stable knocking-down human gastric cancer cell lines. Goal was to determine the different gene expression between control and GAPLINC stable knocking-down human gastric cancer cell lines. Control and GAPLINC stable knocking-down human gastric cancer cell lines were prepared for RNA extraction and hybridization on Affymetrix microarrays.
Project description:Genomic copy number aberrations of 11 gastric cancer cell lines were analyzed by 244k CGH array from Agilent Technologies. Based on this results, we separated the 11 cell lines into 2 groups, with and without copy number increase at chromosome 20q13