DIFFERENTIAL EXPRESSION OF CPB1 AND CRISP3 IN LUMINAL BREAST CANCER MODELS TREATED WITH MIFEPRISTONE AND MEDROXYPROGESTERONE ACETATE.

VICTORIA FABRIS; CLAUDIA LANARI; BRITTA JACOBSEN; ANDRES ELIA; PAOLA ROJAS

Congreso; Reunión Anual de Sociedades de Biociencia 2020; 2020

Several epidemiological studies, supported by experimental research,suggest that progestins exert a relevant role in breast carcinogenesis.Thus, there is an increased interest in targeting progesteronereceptors (PR) for breast cancer treatment. We have recentlyshown that the antiprogestin mifepristone (MFP) inhibited cell proliferationof breast cancer tissue cultures with higher levels of PR isoformA (PRA) than B (PRB), highlighting the relevance of identifyingmarkers to monitor antiprogestin responsiveness. Using RNA-seqwe have previously identified 139 genes differentially expressedin breast carcinomas with high or low PRA/PRB ratio (PRA-H andPRB-H, respectively). The aim of the study was to investigate theexpression of genes that could be used to monitor treatment responsiveness.We focused in CPB1 and CRISP3, since both aresecreted proteins that might be detected in serum. We used twoPRA-H (C4-HI and C7-2-HI) and two PRB-H (C42-HI and C7-HI) tumorsfrom the medroxyprogesterone acetate (MPA)-induced murinebreast cancer model, and the human breast cancer cell lines, T47DYAand T47D-YB. A statistically significant interaction was observedwhen the expression of CPB1 and CRISP3 was studied by qPCR intumors treated with MFP or the progestin MPA (p