Project description:Gene Expression Profiling of HT-29 and Caco-2 colon cancer cell lines untreated compared with EGF, Cetuximab, Gefitinib,EGF plus Cetuximab and EGF plus gefitinib treatments. Keywords: Gene Expression Profiling
Project description:Microarrays were used to analyze differential gene expression and to help determine the efficacy of Iressa (gefitinib), a tyrosine kinase inhibitor, on endometrial cancer cells. Type I Ishikawa H and type II Hec50co endometrial carcinoma cells both express EGFR and sEGFR, but differ markedly in their responsiveness to the EGFR inhibitor gefitinib. This difference is paralleled by differences in the expression of sEGFR and EGFR, as well as in their transcriptional response following treatment with either EGFor gefitinib. The small cluster of differently regulated genes reported here in these type I vs. type II endometrial cancer-derived cell lines may identify candidate biomarkers useful for predicting sensitivity to EGFR blockade. Type I (Ishikawa H cells) and type II (Hec50co) derived endometrial carcinomas, were dosed with either EGF(epidermal growth factor) or Iressa (gefitinib) for 12 or 24 hours and gene expression was examined.
Project description:Despite advances in surgery and radiotherapy of uveal melanoma (UM), many patients develop distant metastases that poorly respond to therapy. Improved therapies for the metastatic disease are therefore urgently needed. Expression of the epidermal growth factor receptor (EGFR), a target of kinase inhibitors and humanized antibodies in use for several cancers, had been reported. 48 human UMs were analyzed by expression profiling. Evidence for signaling in tumors was obtained through the application of a UM-specific EGF signature. The EGFR specific kinase inhibitor, Gefitinib, and the humanized monoclonal antibody, Cetuximab, were tested for their effect on EGFR signaling. Natural killer cell mediated antibody-dependent cellular cytotoxicity (ADCC) and TNF-alpha release was analyzed for Cetuximab. EGFR appears suited as a novel molecular drug target for therapy of uveal melanoma. Gene expression profiles of 19 unique samples from uveal melanoma patients were measured.
Project description:Aberrant activation of signaling pathways controlled in normal epithelial cells by the epidermal growth factor receptor (EGFR) has been linked to cetuximab (a monoclonal antibody against EGFR) resistance in head and neck squamous cell carcinoma (HNSCC). To infer relevant and specific pathway activation downstream of EGFR from gene expression in HNSCC, we generated gene expression signatures using immortalized keratinocytes (HaCaT) subjected to either ligand stimulation or pharmacological inhibition of the signaling intermediaries PI-3-Kinase and MEK or transfected with EGFR, RELA/p65, or HRASVal12. The gene expression patterns that distinguished the various HaCaT variants and conditions were inferred using the Markov chain Monte Carlo (MCMC) matrix factorization algorithm Coordinated Gene Activity in Pattern Sets (CoGAPS). This approach inferred gene expression signatures with greater relevance to cell signaling pathway activation than the expression signatures inferred with standard linear models. Furthermore, the pathway signature generated using HaCaT-HRASVal12 further associated with the cetuximab treatment response in isogenic cetuximab-sensitive (UMSCC1) and -resistant (1CC8) cell lines. Our data suggest that the CoGAPS algorithm can generate gene expression signatures that are pertinent to downstream effects of receptor signaling pathway activation and potentially be useful in modeling resistance mechanisms to targeted therapies. 58 total RNA collected from HaCaT cell lines with combinations of the following experimental conditions: forced expression of EGFR, RELA/p65, and HRAS-VAL12D; grown in PBS, serum starve, and media stimulated with TNF or EGF; treated with gefitinib, LY294002, and U1026.
Project description:Despite advances in surgery and radiotherapy of uveal melanoma (UM), many patients develop distant metastases that poorly respond to therapy. Improved therapies for the metastatic disease are therefore urgently needed. Expression of the epidermal growth factor receptor (EGFR), a target of kinase inhibitors and humanized antibodies in use for several cancers, had been reported. 48 human UMs were analyzed by expression profiling. Evidence for signaling in tumors was obtained through the application of a UM-specific EGF signature. The EGFR specific kinase inhibitor, Gefitinib, and the humanized monoclonal antibody, Cetuximab, were tested for their effect on EGFR signaling. Natural killer cell mediated antibody-dependent cellular cytotoxicity (ADCC) and TNF-alpha release was analyzed for Cetuximab. EGFR appears suited as a novel molecular drug target for therapy of uveal melanoma.
Project description:The cetuximab resistant FaDuCR cell lines were established after continuous treatments with a 10 µg/mL final concentration of cetuximab. Those cells could freely proliferate in 10 µg/mL cetuximab containing medium, and were named FaDuCR. We used microarrays to detail the gene expression in FaDuCR and FaDu-parental cells to screen for transcripts correlated with cetuximab resistance.
Project description:10 cell lines (five cetuximab sensitive and five cetuximab resistant) were selected for gene copy number array analysis on the Affymetrix SNP 6.0 platform. 39 protein coding genes were amplified in cetuximab resistant cells and normal in sensitive cells, all present on genomic regions 11q22.1 or 5p13-15. Five genes were selected for quantitative PCR verification, namely, YAP1 and TRPC6 (11q22.1) and PDCD6, TPPP, and PTGER4 (5p13-15). An extended panel of totally 10 cetuximab resistant and 10 sensitive cell lines verified that YAP1 amplified cells are cetuximab resistant. YAP1 gene amplification was highly correlated to the YAP1 mRNA expression, which was significantly higher in cetuximab resistant cells than in sensitive. YAP1 downregulation resulted in increased cetuximab sensitivity in one of two cetuximab resistant cell lines investigated and growth inhibition in another. We conclude that YAP1 is a marker for cetuximab resistance in head and neck cancer. head and neck cancer cell lines with established cetuximab response were selected. 5 cetuximab resistant cell lines and 5 cetuximab sensitive cell lines were selected for gene genome wide gene copy number analysis on the Affymetrix SNP6.0 array
Project description:Microarrays were used to analyze differential gene expression and to help determine the efficacy of Iressa (gefitinib), a tyrosine kinase inhibitor, on endometrial cancer cells. Type I Ishikawa H and type II Hec50co endometrial carcinoma cells both express EGFR and sEGFR, but differ markedly in their responsiveness to the EGFR inhibitor gefitinib. This difference is paralleled by differences in the expression of sEGFR and EGFR, as well as in their transcriptional response following treatment with either EGFor gefitinib. The small cluster of differently regulated genes reported here in these type I vs. type II endometrial cancer-derived cell lines may identify candidate biomarkers useful for predicting sensitivity to EGFR blockade.
Project description:Global mRNA expression profiling of patient derived colon cancer xenograft models (N=13) were collected using Agilent human whole genome array (G4845A AMADID 026652, cRNA 4x44k V2) . All xenograft models carried an activating. All Mice were either untreated (controls) or treated with treated with cetuximab (25 mg/kg, twice weekly, i.p., Merck) and trametinib (0.5 mg/kg, five subsequent days per week, p.o., Hycultec) to establish response characteristics. Tumors showing disease control under the combination treatment were chronically treated to establish cetuximab secondary resistant tumors which was successful for BoC2 and BoC56 .Primary resistant PDX tumors (BoC51, 109, 117, and 122) and secondary resistant tumors (BoC2 and BoC56) were harvested at the end of treatment (days 29 to 59). For BoC2 and 56, untreated control Tumors (K) were harvested once tumors reached approx. 1000mm3 in volume.