Role of the Actin Cytoskeleton in the Formation Ovarian Carcinoma Tumoral Spheroids in vitro

LUJEA, NOELIA; MASNER, MARTIN; KUNDA, PATRICIA

Buenos Aires

Congreso; LIII SAIB; 2017

Epithelial ovarian cancer is highly proliferative and metastatic.During the dissemination, exfoliated ovarian tumor cells are carriedvia peritoneal fluid to secondary sites in the abdominal cavity wherethey survive like individual cells or attach themselves forming tumoralspheroids. We propose that the actin cytoskeleton and theactivation of the ERM proteins are key to ensuring cell survival, proliferationand tumor formation in the peritoneal fluid.The in vitro model of cell spheroids formation in soft agar was usedsince is one of the most well characterized models for 3D culturedue to its simplicity, reproducibility, and similarity to peritoneal metastasismodel. The cell lines SCOV3 (epithelial ovarian cancer) andHeLa were cultured at different densities on 0.5% soft agar. After 5,10, 15 and 20 DIV (days in vitro) the diameter of the spheroids wasmeasured. Survival, proliferation and number of cells per spheroidwere analyzed by immunostaining with DAPI, PhosphoHistone3, Tubulinand Phalloidin. WB and IF were used to observe expressionlevels and distribution patterns of the activated ERMs proteins.HeLa cells spheroids were significantly large in size and morecompacted compared to SCOV3 cells spheroid after 20 DIV. Cellsurvival and proliferation decreased after 15 DIV. PhosphoERMwas distributed in the peripheral layer of the HeLa cells spheroids,whereas in SCOV3 spheroids showed cortical distribution aroundeach cell forming the spheroid.In this work the experimental conditions were standardized for theformation of cellular spheroids in soft agar for the analysis of peritonealmetastasis. It could be observed that the ERM proteins inSCOV3 cells probably play a structural role, guaranteeing the survivaland stability of the spheroid in a different way to HeLa cells.Keywords: Epithelial ovarian cancer, cells spheroids, actin cytoskeleton,ERM proteins