AMPLIFICATION OF 19Q13.1-Q13.2 SEQUENCES IN OVARIAN-CANCER - G-BAND, FISH, AND MOLECULAR STUDIES

In this study of ovarian carcinoma, we extended previous findings by p erforming FISH using chromosome 19 paint and microFISH probes and pati ent samples with and without abnormalities of chromosome 19 identified by G-banding. Karyotype interpretations of der(19) were confirmed, wh ile additional 19 translocations were also detected by FISH with 19WCP in some cases. Similar FISH studies of ovarian carcinoma cell lines f ound chromosome 19 abnormalities even after extensive in vitro culture . MicroFISH probes were generated by chromosome microdissection from t wo cases with hsr(l9) and mapped to 19q13.2 and 19q13.1-.2, respective ly. FISH with these microFISH probes alone or in combination with a 19 WCP probe to four patient samples and seven cell lines showed that 65 % of chromosome 19 structural abnormalities contained 19q13.1-q13.2 se quences, sometimes as large hsrs. Ovarian cancer cell lines showed amp lification and overexpression of the AKT2 putative oncogene, but not t he ERCC-2 DNA repair gene in this chromosomal region. In addition to A KT2, amplification and overexpression of other yet-unidentified genes in the 19q13.1-q13.2 region may contribute to ovarian carcinoma pathog enesis or progression.