Ovarian carcinoma project

Ovarian carcinoma – Molecular and functional characterization of a KRAS oncogene-driven tumor model

We have established an ovarian cancer model based on ovarian epithelial cells. To mimick oncogenic pathway activation, which often is mediated by membrane-based receptors in the clinical setting, we introduced and expressed a mutated KRAS gene in those cells.  Transfected cells exhibit the typical features of transformation in vitro such as anchorage-independence, epithelial-mesenchymal transition (EMT) and motility. Progressively growing tumors are formed in nude mice following subcutaneous or intraperitoneal injection of cells. The malignant phenotype is associated with numerous alterations of gene expression. To understand the causal role of these alterations and the mechanisms of gene deregulation, we perform functional studies. For example, we investigate the role of the HMGA2 protein, an architectural transcription factor, in KRAS-transformed ovarian epithelial cells. HMGA2 expression is silenced by RNA interference and the effects on proliferation, EMT and anchorage independence are determined. For comparison, an HMAG2 expression vector is introduced into normal ovarian epithelial cells to find out, if HMGA2 may act as a oncogene itself. We measure the transcription of KRAS-responsive target genes by interrogating a customized oligonucleotide microarray (RASTA, RAS target array), which represents approx. 300 validated deregulated genes. Moreover, we search for transcription factor binding sites in the regulatory regions of HMGA2-regulated targets. This will help to elucidate the network of HMGA2, acting a as a potential master regulator, and interacting specific transcription factors driving malignancy in the ovarian epithelium.

Support

Supported by: Berlin Cancer Society

Head

Prof. Dr. rer.nat. Reinhold Schäfer
Molecular Tumor Pathology Laboratory
t: +49 30 450 536 072