epidermal-growth-factor and norcantharidin

Norcantharidin (NCTD) is a demethylated derivative of cantharidin demonstrated to have anti-proliferative, anti-inflammatory, and anti-fibrosis properties. The purpose of the current study is to investigate the underlying mechanisms and signaling pathways affected by NCTD in human ARPE-19 cells.. Cell growth and rate of proliferation were assayed by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay, colony formation assay, and cell cycle distribution/quantification. Cell motility was detected with in vitro migration assay. The level of epithelial-mesenchymal transition (EMT)-related proteins and mRNA (Snail, Slug, E-cadherin) were detected using Western blotting, real-time quantitative polymerase chain reaction, and immunofluorescence assay. Overexpression of Snail plasmid was determined by transfection assay.. We found that NCTD reduced epidermal growth factor (EGF)-induced ARPE-19 cell viability and proliferation through increasing the p21 and p27 expression and decreasing the cyclin D1 expression. NCTD also inhibited EGF-mediated EMT and cell motility through increased protein and mRNA levels of E-cadherin and decreased Snail in EGF-induced ARPE-19 cells. Overexpression of Snail significantly decreased ARPE-19 cell motility and increased E-cadherin expression in NCTD-treated cells. Additionally, when NCTD was combined with a PI3K inhibitor (LY294002) significantly decreased the p-AKT and Snail expression, and increased the E-cadherin expression of EGF treatment in ARPE-19 cells.. The current findings revealed that NCTD suppresses the EGF-induced proliferation, motility, and EMT of ARPE-19 cells through inactivation of the AKT-mediated Snail/E-cadherin pathway. NCTD may be a potential preventive agent for proliferative vitreoretinopathy.

Topics: Cadherins; Cell Line, Tumor; Cell Movement; Cell Proliferation; Epidermal Growth Factor; Epithelial-Mesenchymal Transition; Humans; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; RNA, Messenger

Norcantharidin is the demethylated analog of cantharidin isolated from blister beetles (Mylabris phalerata Pall.). In this study, we evaluated whether norcantharidin exhibits anticancer effects against the human non-small cell lung cancer cell lines A549 (epidermal growth factor receptor (EGFR) mutation-negative) and PC9 (EGFR mutation-positive). Our results revealed that norcantharidin dose-dependently retards cell growth, arrests cell cycle at G2/M phase, reduces cell migration, and even induces apoptosis at the concentration of 100 µM. Moreover, we found that norcantharidin enhances the anticancer effects of gefitinib and cisplatin. Norcantharidin exhibited similar potency of anticancer effects against the two cell lines with different EGFR mutation status and did not affect EGF-induced EGFR phosphorylation, suggesting that the EGFR signaling may not be the target of norcantharidin. In conclusion, our results suggest that norcantharidin exhibits anticancer effects against non-small cell lung cancer cells in vitro and support its potential as a chemotherapeutic agent for treating non-small cell lung cancer.

Topics: Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Blotting, Western; Bridged Bicyclo Compounds, Heterocyclic; Carcinoma, Non-Small-Cell Lung; Cell Adhesion; Cell Cycle; Cell Movement; Cell Proliferation; Cisplatin; Epidermal Growth Factor; ErbB Receptors; Flow Cytometry; Fluorescent Antibody Technique; Gefitinib; Humans; Lung Neoplasms; Mutation; Phosphorylation; Quinazolines; Signal Transduction; Tumor Cells, Cultured