IN VITRO ASSESSMENT OF 17ß-ETHINYLESTRADIOL AND LEVONORGESTREL ON BREAST CANCER MCF-7 AND MDA-MB-231 CELL LINES

Abstract

Oral contraceptives are widely used drugs, especially in the prevention of unwanted pregnancies. Although oral contraceptives are used in the management of several pathologies, their toxicity on the female body raises a question mark. The specialised literature highlights a connection between their use and the development of breast cancer, but there are uncertainties. The current study evaluates in vitro two recognised contraceptives-levonorgestrel (LG) and 17β-ethinylestradiol (EE) regarding the cytotoxicity and the changes occurring in two breast cancer cell lines MCF-7, a cell line positive for the oestrogen receptor (ER+) and MDA-MB-231, a triple-negative cell line (TNBC), without oestrogen and progesterone receptors. The obtained results reported that after 24 hours of exposure at LG, EE and LG-EE, the cell viability decreases with the increase of the dose, while with the increase of the exposure period, stimulation of proliferation is evident. Moreover, differences are observed between the two cell lines. At the level of MCF-7 cells, EE has a more pronounced stimulatory effect, while on the MDA-MB-231 line, LG induces cell proliferation and a low cytotoxic effect. Also, 24 hours after stimulation, signs of apoptosis are recorded at the dose of 7.5, while at the lowest concentration, a migratory effect is observed. Following the results, an affinity of EE for the MCF-7 line is observed due to the receptors present. However, additional investigations are needed to determine the mechanism of action of oral contraceptives on breast cancer.