MOLECULAR BIOLOGICAL STUDIES ON TRANSCRIPTION FACTOR ESTROGEN-RECEPTOR IN BREAST CANCER TREATED WITH LECTIN

Abstract

Proteins with legume lectin domains are known to possess a wide range of biological functions.The antitumor effects of Concanavalin-A (ConA) lectin and Tamoxifen (potent antagonist of estrogen and induces apoptosis in MCF-7 cells) on human breast carcinoma cells were investigated in vitro.Human breast carcinoma MCF-7 cells were examined, cell viability, proliferation and cytotoxicity of MCF cells treated with ConA and Tamoxifen using morphological analysis and MTT cytotoxicity assay.The effects of ConA compared to Tamoxifen on the expression of the transcription factor Erα and the expression of antiapoptosis gene (Bcl2) in breast cancer MCF7 cell line were evaluated by RT-PCR.The microscopic examination of cells indicated that ConA induced significant cellular alterations typical of apoptosis cell-death in a comparable manner as Tamoxifen.ConA showed also proliferation inhibition activity, however it was lower than tamoxifen, as indicated by MTT growth inhibition assay.The IC50 of ConA is 7.55 µM and of Tamoxifen is 2.75 µM.The expression of Erα and Bcl2 proteins after treatment with ConA were significantly decreased.In conclusion: ConA induced significant apoptosis and inhibited the proliferation of breast cancer cells that may be through mechanism involve reduction in the expression of ERα and anti-apoptotic gene BCl-2.Finally, our results indicate that ConA exerts anti-tumor actions against human breast carcinoma MCF-7 cells in vitro and confer support for more research to unravel the potentials of using concanavalin-A as complementary treatment of ER+ breast cancer.