The Potential Effects And Mechanism Of Quercetin On Cancer Preventing And Therapy

The aim of this study was to reveal the potential effects of quercetin on cancer preventing and therapy, and to explore its mechanism. In the field of cancer preventing effects study, we investigated the effects of quercetin on pulmonary pathomorphological changes and blood lymphocytes DNA damages in mice induced by B[a]P, detected the changes of CYP1 A1 activity in mice lung microsome in this process, and in L-02 cell line and human liver microsomes in the other in vitro study, and discussed the potential effects and mechanism of quercetin on the early stage of carcinogenesis induced by B[a]P. In the field of cancer therapeutic effects study, we investigated the inhibitive effects of quercetin on proliferation of human lung carcinoma A549 cell line and murine melanoma Cloudman S91 cell line in a in vitro study, and explored its mechanism by investigating the effects of quercetin on cell cycle, apoptosis and the expressions of p53 and bcl-2 in Cloudman S91 cell line. On the other hand, in some in vivo studies, we investigated the inhibitive effects of quercetin (given to mice per os or by ip injection) on proliferation of implanted Lewis lung carcinoma in mice; prepared the extract from bud of Sophora japonica (named as EBSJ for short); investigated and compared the effects of quercentin and EBSJ on tumor growth inhibition in Lewis lung carcinoma of mice, and investigated the combined therapeutic effects with Cisplatin, studied their effects on the weights of immune organs and blood system. Meanwhile, to explore the mechanism of EBSJ on tumor growth inhibition, we studied the effects of EBSJ on the cell cycle distribution and the proliferating cell nuclear antigen (PCNA) expression of tumor cell in Lewis lung carcinoma of mice, The abstracts of each part are as follow:In the part of study for cancer preventing effects: we investigated the inhibitive effects of quercetin on CYP1A1 activities of L-02 cell line and human liver microsomes in a in vitro study. Inhibition of cell growth of L-02 cells was assayed by using a MTT method. Results showed that L-02 cells were inhibited by quercetin with an IC50 value of 20μmol/l. This value was used to make the treatment concentration range of quercetin in the following experiment. A dose-response analysis showed that the inhibition of CYP1A1 activity of L-02 cell line in the quercetin concentration of...