Summary: | 碩士 === 國立中興大學 === 生物醫學研究所 === 104 === Cancer is one of the most leading causes of death. Statistic data indicated that lung cancer has the highest mortality rate in all cancers. The cancer incident rate of men and women is prostate cancer and breast cancer, respectively, while the incident rate of lung cancer is the second. Therefore, the impact on lung cancer is not underestimated. Approximately 85% of lung cancer is non-small cell lung cancer (NSCLC). However, the treatment of chemotherapy might fail in NSCLC patients because of drug resistance. In addition, the 5-year survival rate was only 13%. So, it’s urgent to study more treatment of lung cancer. Due to the expensive cost of chemotherapy, the scientists were trying to find some effective natural product. Flavonoids have the effect of anti-inflammatory, anti-virus, anti-cancer, and preventing heart disease. Flavonoids mainly present in plants, such as grapes, legumes, citrus fruits. Citrus peels are rich in flavonoid, but due to certain components of citrus peels have poor bioactivity and solubility; the development of natural products using chemical modification to enhance the bioactivity. First, using the components of citrus peels extract and its derivates, we found that the tangeretin derivates, 5-acetyloxy-6, 7, 8, 4’-tetramethoxyflavone (5-AcTMF) had the most significant effect of cytotoxic activity. And, using four kinds of NSCLCs, we found that CL1-5 NSCLC was most sensitive to 5-AcTMF. So in the research, we further evaluated the anti-cancer effect and its mechanism of 5-AcTMF on CL1-5 NSCLC. We found that 5-AcTMF inhibit cell growth and induced G2/M cell cycle arrest associated with cdc2 and cdc25c and induce apoptosis associated with the intrinsic pathway activation, down regulation of Bcl-2, XIAP, Survivin, disrupt the mitochondria membrane potential. In addition, using flow cytometry and western blot, we found that 5-AcTMF increase the fluorescent of acidic vesicular organelles, LC3Ⅱ protein level and LC3 puncta formation which indicated that the compound could induced autophagy. Moreover, 5-AcTMF inhibits the PI3K/AKT/mTOR signaling pathway. In animal model, we found that 5-AcTMF could delay tumor growth. Also, immunohistochemistry analysis reveals that 5-AcTMF induced CL1-5 cells apoptosis and autophagy in vivo. Taken together, we confirmed that 5-AcTMF has the effect of anticancer on CL1-5 NSCLC by induced cell apoptosis, cell cycle arrest and autophagy in vitro and in vivo. 5-AcTMF is a potential compound in the treatment of NSCLC.
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