Absence of p51 alteration in human ovarian cancer

The p51 gene encodes a protein with significant homology to p53, thus, it i s a candidate tumor suppressor gene. To investigate the involvement of the p51 gene in human ovarian carcinogenesis, p51 gene alterations were examine d in primary ovarian cancers and ovarian cancer cell lines. Mutation analys is of the p51 gene was performed in 40 primary ovarian cancers and 6 ovaria n cancer cell lines using the PCR-SSCP and direct sequencing methods. Expre ssion of p51 mRNA was examined in 9 primary ovarian cancers and 5 ovarian c ancer cell lines by Northern blot and RT-PCR analyses. No mutations of the p51 gene causing amino acid substitutions or frameshifts were detected in e ither primary tumors or cancer cell lines by PCR-SSCP analysis of the entir e coding region, although several genetic polymorphisms were detected in th ree samples. Allelic imbalance was detected in 3 of 19 (16%) primary ovaria n cancers. No p51 gene expression was detected in 9 primary ovarian cancers and the corresponding normal ovarian tissues by Northern blot and by RT-PC R analyses. One of 5 ovarian cancer cell lines showed p51 gene expression b y Northern blot analysis (20%). These results indicated that p51 gene expre ssion was silent in normal ovarian tissues and primary ovarian cancers, and that mutation of the p51 gene does not pray a major role in the developmen t of ovarian cancer.