Endocrine Abstracts

Synthetic pyrethroids (SPs) are the most common pesticides which are recently used for indoor pest control. The widespread use of SPs has resulted in the increased exposure to wild animals and humans. Recently, some SPs are suspected as endocrine disrupting chemicals (EDCs) and have been assessed for their potential oestrogenicity by adopting various analyzing assays. In this study, we examined the estrogenic effects of λ-cyhalothrin (LCT) and cypermethrin (CP), the most commonly used pesticides in Korea, in BG-1 ovarian cancer cells expressing estrogen receptors (ERs). To evaluate the estrogenic activities of two SPs, LCT and CP, we performed MTT assay and reverse-transcription polymerase chain reaction (RT-PCR) for LCT or CP treated BG-1 ovarian cancer cells. In MTT assay, LCT (10⁻⁶ M) and CP (10⁻⁵ M) significantly induced the growth of BG-1 cancer cells in a dose-dependent manner. LCT or CP-induced cell growth was reversed by addition of ICI 182 720 (10⁻⁸ M), an ER antagonist, suggesting that this effect appears to be mediated by an ER-dependent manner. Moreover, RT-PCR results showed that transcriptional level of ERα was significantly down-regulated by LCT and CP. Taken together, these results indicate that LCT and CP may possess estrogenic potentials to stimulate the growth of ovarian cancer cells expressing ERs via an ER-dependent manner. Based on the observations from these in vitro results, we will examine in vivo oestrogenicity of LCT and CP in a xenografted mouse model transplanted with human BG-1 ovarian cancer cells (This work was supported by Basic Science Research Program though the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (MEST) (2013R1A1A2059092)).