Role of FGF-8 in Breast Cancer

Abstract

Abstract : This proposal seeks to evaluate the frequency of FGF8 overexpression in mammary carcinogenesis. We examined the frequency of FGF8 expression in human breast cancer cell lines and fresh-frozen pathological specimens by reverse transcription-polymerase chain reaction (RT-PCR) methods. Total RNA was prepared from human breast cancer cell lines and pathological specimens and converted into cDNA by reverse transcription. The resulting cDNAs were analyzed by PCR and gel electrophoresis. We used primers specific to human FGF8 that did not amplify mouse Fgf8/8. We observed expression of FGF8 in 8 of 24 human breast cancer cell lines, 2 of 16 lymph nodes containing metastatic breast cancer, and 10/30 primary human breast cancer specimens. Under the conditions employed, normal mammary tissue and lymph nodes do not have detectable expression of FGF8. Attempts to examine archival paraffin-embedded tissue for FGF-8 protein by immunohistochemical methods was not successful because of technical problems with the immunological reagents used. In summary, approximately 30% of human breast cancers overexpress FGF8. As MMTV-FGF8b transgenic mice have a mammary cancer phenotype, the observed overexpression of FGF8 likely contributes to the pathogenesis of cancer in those overexpressed cases.