The EC cells were transfected with siRNA oligonucleotides (20 M) using lipofectamine 3000 (ThermoFisher Scientific Inc., California, US) following manufacturer’s protocols, and then collected after 72 h for MTT and Western blotting assay. MTT Assay Cells were separately seeded into 96-well plates at a concentration of 4,000 cells/well, and then subjected to MTT assay. paclitaxel treatment migration and invasion of human neuroblastoma cells (18C21). Because of the association between PBDEs and hormone levels in humans (22), the impact of PBDEs on hormone-dependent cancers has become a topic of interest. BDE-47 was thought to be an estrogen disruptor with adverse effects on sexual behavior and reproductive function in zebra fish (23). Furthermore, BDE-47 could induce oxidative stress in MCF-7 cells by inhibiting the pentose phosphate pathway (16). An epidemiological survey reported that the serum concentration of BDE-47 in breast cancer women was significantly higher than that of controls (24). However, this pattern was not consistent across all cancers, for instance, BDE-47 could stimulate cell proliferation in human ovarian carcinoma cells OVCAR-3 but not in MCF-7 breast cancer cells (25), reflecting the complicated and inconsistent mechanisms underlying the effect Mouse monoclonal to CD3/CD4/CD45 (FITC/PE/PE-Cy5) of BDE-47 on different types of cancers. Mulberroside C Chemotherapy is commonly used to treat disseminated or recurrent EC, often after the failure of hormonal therapy. Although the management of EC has undergone a dramatic shift in recent years, and that early-stage EC has a favorable prognosis, the advanced or recurrent EC still has a poor prognosis partially because of chemoresistance. The underlying causes of drug resistance in EC are multi-factorial. Resistance to anti-microtubule agents such as paclitaxel and cisplatin (DDP) is particularly challenging given the importance of these agents in first-line treatment of EC (26). A recent study revealed that cadmium prevented the 5-fluorouracil cytotoxic effect by modifying cell cycle and apoptotic profiles in MCF-7 cells (27). Nonetheless, the potential antagonist effect Mulberroside C of BDE-47 against chemotherapy sensitivity of EC has not been well-clarified. Since EC is an estrogen-dependent cancer and BDE-47 could cause endocrine disruption, we hypothesized that BDE-47 might affect the progression and drug resistance of EC. In this study, the effect of BDE-47 on two human being EC cell lines, Ishikawa and HEC-1B cells, was investigated. It has been found that chronic BDE-47 exposure could result in phenotypic plasticity, promote progression, and even chemoresistance in EC cells, at least in part, via ER/GPR30 and EGFR (epidermal growth element receptor)/ERK (extracellular-regulated protein kinase) signaling pathways. Materials and Methods Cell Lines and Cell Tradition Two endometrial malignancy cell lines, Ishikawa (ER-positive/EGFR-positive), and HEC-1B (ER-negative/EGFR-positive), were generously provided by Dr. Xiaolong Wei (Malignancy Hospital of Shantou University or college Medical College, Shantou, China) and Dr. Bo Qiu (Southern Medical University or college, Guangzhou, China). Both these two cell lines have been authenticated. These cells were maintained in total RPMI 1640 medium (Gibco, ThermoFisher Scientific Inc., California, US), supplemented with 10% fetal bovine serum (FBS, Biological Market, Kibbutz BeitHaemek, Israel) at 37C inside a 5% CO2 incubator. To develop a chronically poisoned cell model, both Ishikawa and HEC-1B cells were exposed to 10 M BDE-47 (Lot No. 3798900, Chemservice Inc., Worms, Germany) for Mulberroside C up to 45 days before the experiments, and were designated mainly because Ishikawa-BDE-47 Mulberroside C and HEC-1B-BDE-47, respectively. Cell Treatment To investigate the effect of BDE-47 on paclitaxel- and DDP-induced cytotoxicity in EC cells, Ishikawa-BDE-47 (10 M), HEC-1B-BDE-47 (10 M), and their parental cells (1 104) were treated with 0, 0.1, 1, 1.25, 5 M of paclitaxel (Bristol-Myers Squibb Organization, New York, USA) and 0, 1.25, 2.5, 5, 10, 20, 50, 100 M of DDP (Hansoh pharma co. LTD, Jiangsu, China) for 48 h, respectively. After that cell viability was evaluated by MTT assays. To further determine the cross-talk between ER/GPR30 and EGFR/ERK transmission pathway, 10 M erlotinib (No. #5083, Cell Signaling Technology Inc., Danvers, Massachusetts, US) and 20 M PD98059 (No. #9900, Cell Signaling Technology Inc., Danvers, Massachusetts, US) were used to Mulberroside C inhibit EGFR autophosphorylation and ERK kinases for 48 h before MTT and European blotting.