中文摘要：

茶多酚是绿茶的主要活性成分,具有广泛的生物学作用,如中度选择性抗肿瘤活性。茶多酚在肿瘤预防和治疗中的作用靶点广泛,能抑制生长因子介导的信号通路,降低丝裂原活化的蛋白激酶和活化蛋白转录因子-1的活性,阻断NF-κB信号通路,减少蛋白酶体活性,减低COX-2过度表达,减弱肿瘤细胞二氢叶酸还原酶和端粒酶的活性,抑制DNA甲基化和基质金属蛋白酶的活性等。茶多酚能增加传统抗肿瘤药物或靶向抗肿瘤药物的抑瘤作用,能逆转肿瘤细胞对长春新碱（VCR）、多柔比星、5-氟尿嘧啶等的耐药性,同时对顺铂引起的肾毒性、伊立替康导致的肠毒性以及博来霉素引起的基因毒性均具有减缓作用,茶多酚还可以通过免疫调节增加肿瘤疫苗的抗瘤作用。可见,茶多酚与抗肿瘤药物联用具有增效、减毒以及逆转耐药性的作用,可能作为生化调节剂应用于临床。

英文摘要：

Tea polyphenols（TPs）,major biological active constituents of green tea,exert moderate and selective anticancer effects.Molecular mechanisms of TPs in cancer prevention and treatment involve multiple potential molecular targets.TPs inhibit growth factor receptor-mediated signal transduction pathway,decrease the activities of mitogen activated protein kinases and activator protein transcription factor-1,block nuclear factor-κB signaling pathway,reduce proteasome activity,lower overexpression of COX-2,subside dihydrofolate reductase and telomerase,and inhibit DNA methylation and matrix metalloproteinases.Furthermore,TPs enhance the inhibitory effect on the growth of cancers by traditional anticancer drugs or targeted antitumor drugs in vitro and in vivo and reverse multidrug resistances of cancer cells to vincristine,doxorubicin,and 5-fluorouracil.Besides,TPs reduce the nephrotoxicity induced by cisplatin,ameliorate irinotecan-induced side effects in the small intestine of mice,and decrease bleomycin-caused DNA damage in human leukocytes.TPs also increase antitumor activity of vaccine through immunological modulation.TPs play roles of the augmentation of antitumor effects,the reversal of multidrug resistance,and the reduction of side effects of chemotherapeutic drugs.TPs could be used as biochemical modulators in cancer therapy.