These studies attempt to examine some of the critical differences in gene expression and altered responsiveness to transcriptional regulatory agents that accompany the progression of benign tumors to metastatic lesions. Biological parameters being studied include gene expression, protein expression tumorigenicity, metastasis and in vitro invasiveness. In order to identify factors involved in tumor progression we have established epithelial cell lines from murine pulmonary adenocarcinomas. Additionally we have developed allografts from spontaneous and chemical induced primary tumors that have been serially passaged in nude mice. A method of quantitative PCR amplification has been used to analyze messenger RNA levels in cell lines and solid tumors. We have obtained several established human lung adenocarcinoma cell lines and developed a number of adenocarcinoma and squamous cell tumor xenografts in BNX mice to compare with the results observed in murine tumors and cell lines with respect to proteinases and their inhibitors. In addition to proteinases and their inhibitors we are also studying the effects of modulating the expression of the putative metastasis suppressor gene nm23. Expression vectors containing the sense and antisense orientation of the nm23 coding region are being transfected into nonmetastatic cell lines that express high levels of nm23 message and metastatic cell lines with low nm23 expression levels. Responsiveness to growth factors such as TGFbeta and modulators of differentiaton and cell proliferation such as retinoic acid and Vitamin D3 are being analyzed in murine lung adenocarcinoma cell lines with respect to anchorage independent growth and in vitro invasiveness. Greater that 30% of all human mammary tumors contain amplified and overexpressed HER2/neu with an additional 25% overexpressing HER2/neu in the absence of amplification. Greater than 80% of all pancreatic tumors contain codon 12 mutations in K-ras. We are generating zenografts in BNX mice from human mammary and pancreatic adenocarcinomas for use in evaluating the efficacy of antisense DNA therapy against growth and metastatic spread.
