EGFR Isoforms and Gene Regulation in Human Endometrial Cancer Cells

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.