Abstract 1921: Mutational and expressional analyses of DICER1 gene in ovarian stromal tumors and other common tumors.

Abstract

Abstract Recurrent missense somatic mutations in DICER1 gene affecting exons 25 and 26 have recently been reported in non-epithelial tumors of ovary, especially in Sertoli-Leydig cell tumors (SLCT). Such a recurrent nature of the mutations strongly suggests that DICER1 mutation may play an important role in the development of ovarian non-epithelial tumors. The aim of this study was to further characterize the DICER1 mutations in human tumor tissues. We analyzed the DICER1 mutations in 2,819 tumor tissues from ovary and other organs by single-strand conformation polymorphism analysis. We found the DICER1 exon 25 and 26 hot-spot mutations in 2 of 14 SLCT (14.3%) and one of 132 non-Hodgkin lymphomas (0.8%), but none in other tumors. In SLCT, DICER1 expression was observed in Sertoli cells, but neither in Leydig nor spindle-shaped cells. We also analyzed DICER1 expression in lung, stomach, colon and prostate cancer tissues. DICER1 expression was lost in 37% of prostate cancers, but not in lung, stomach and colon cancers. Our data indicate that DICER1 recurrent mutations commonly occur in SLCT, but the incidence was significantly lowerthan that in the earlier study. Our data suggest that both DICER1 mutation and its expression loss may be important in tumor pathogenesis and that they are tumor type-specific. Citation Format: Min Sung Kim, Eun Mi Je, Youn Jin Choi, Nam Jin Yoo, Sug Hyung Lee. Mutational and expressional analyses of DICER1 gene in ovarian stromal tumors and other common tumors. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1921. doi:10.1158/1538-7445.AM2013-1921