Background: Mismatch repair (MMR) and microsatellite instability (MSI) occur in prostate cancer, but their role has not been well documented.
Methods: In 6 cell lines and 22 xenografts from prostate cancer, PCR and gel electrophoresis were performed to detect MSI by analyzing microsatellite markers BAT-25 and BAT-26 and to detect frameshift mutations in mononucleotide repeats in BAX, IGF2R, MSH3, MSH6, and TGFBR2.
Results: Four of 6 (67%) cell lines and 3 of 22 (14%) xenografts showed MSI. At least 1 frameshift mutation was detected in the same 4 (67%) cell lines and in 5 of 22 (23%) xenografts. While MSH3 was frequently mutated in cell lines, BAX and TGFBR2 showed frequent alterations in both cell lines and xenografts.
Conclusions: MSI related to MMR deficiency is relatively frequent in high-grade tumors, and mutations in MSI target genes involved in cell death and proliferation appeared to be selected for during prostatic carcinogenesis.
Prostate 66:660-666, 2006. (c) 2005 Wiley-Liss, Inc.