TP53, encoding a well-known tumor suppressor p53, plays essential roles in tumor initiation and pro- gression, and is frequently mutated in lung cancer. However, pharmacological stabilization and reactivation of p53 h...TP53, encoding a well-known tumor suppressor p53, plays essential roles in tumor initiation and pro- gression, and is frequently mutated in lung cancer. However, pharmacological stabilization and reactivation of p53 have not been actively explored for targeted cancer therapies. Here, we identified a novel Cyclophilin A （CypA） small molecule inhibitor （ HL001 ） that induces non-small cell lung cancer （NSCLC） cell cycle arrest and apoptosis via restoring p53 expression, and further stabilizes p53 through inhibiting the MDM2-mediated p53 ubiqutination. The down-regulation of G3BP1 by HL001 also contributes to p53 stabilization by inhibiting p53 redistribution from nucleus to cytoplasm. Furthermore, HE001 selectively suppresses tumor growth in p53 wild-type NSCLC harboring Arg72 homozygous alleles （p53-72R） through disrupting interaction between MDM2 and p53-72R in a CypA-de- pendent manner. Finally, administration of HE001 alone or co-treatment with cisplatin promotes significant tumor suppression in orthotopic NSCLC mouse model. Collectively, our preclinical study demonstrated that HE001, a small molecule inhibitor of CypA, selectively activated p53WT 72R homozygote and thus inhibits growth of human lung cancer cells. The results presented here demonstrate that the utility of CypA inhibitors serve as an approach to the targeted therapy for individual lung cancer patient.展开更多
Objective To study the effects and the mechanisms of extract from a leguminous plant （Ammopiptanthus mongolicus cheng f.） （JAl ） in northwest China on inducing apoptosis and inhibiting proliferation of HepG2 hepat...Objective To study the effects and the mechanisms of extract from a leguminous plant （Ammopiptanthus mongolicus cheng f.） （JAl ） in northwest China on inducing apoptosis and inhibiting proliferation of HepG2 hepatocarcinoma cell in vitro. Methods The HepG2 cell line was used as target cells. The effect of 3A 1 on HepG2 cell growth was detected by microculture tetrazolium assay （MTr）, flow cytometry assay, DNA agarose gel electrophoresis and transmission electronic microscopy. The expressive effect of the wt-p53 in HepG2 cells was analyzed with p53 protein test-reagent. Results JAl not only had significant anti-proliferative effects depending upon time and dosage, but also induced apoptosis of HepG2 cells. Apoptotic typical morphological changes were observed in JAl-treated HepG2 cells under transmission electronic microscope, ＂Sub-G 1＂ phase peak occurred in flow cytometry and DNA ＂ladder＂ was found in DNA agarose gel electrophoresis. The expression of the wt-p53 increased in vitro, and 3Al-treated HepG2 and the positive cell percentage of the wt-p53 protein also increased. Conclusions JAl could obviously induce apoptosis and inhibit proliferation of HepG2 cells in vitro, and these effects are closely related with the increase of wt-p53 expression. JAl can be used as a good source of medicinal plant for the treatment of hepatocarcinoma.展开更多
文摘TP53, encoding a well-known tumor suppressor p53, plays essential roles in tumor initiation and pro- gression, and is frequently mutated in lung cancer. However, pharmacological stabilization and reactivation of p53 have not been actively explored for targeted cancer therapies. Here, we identified a novel Cyclophilin A （CypA） small molecule inhibitor （ HL001 ） that induces non-small cell lung cancer （NSCLC） cell cycle arrest and apoptosis via restoring p53 expression, and further stabilizes p53 through inhibiting the MDM2-mediated p53 ubiqutination. The down-regulation of G3BP1 by HL001 also contributes to p53 stabilization by inhibiting p53 redistribution from nucleus to cytoplasm. Furthermore, HE001 selectively suppresses tumor growth in p53 wild-type NSCLC harboring Arg72 homozygous alleles （p53-72R） through disrupting interaction between MDM2 and p53-72R in a CypA-de- pendent manner. Finally, administration of HE001 alone or co-treatment with cisplatin promotes significant tumor suppression in orthotopic NSCLC mouse model. Collectively, our preclinical study demonstrated that HE001, a small molecule inhibitor of CypA, selectively activated p53WT 72R homozygote and thus inhibits growth of human lung cancer cells. The results presented here demonstrate that the utility of CypA inhibitors serve as an approach to the targeted therapy for individual lung cancer patient.
基金This research was supported by the National Key Technologies R&D Program of China (No. 2001BA901A33)
文摘Objective To study the effects and the mechanisms of extract from a leguminous plant （Ammopiptanthus mongolicus cheng f.） （JAl ） in northwest China on inducing apoptosis and inhibiting proliferation of HepG2 hepatocarcinoma cell in vitro. Methods The HepG2 cell line was used as target cells. The effect of 3A 1 on HepG2 cell growth was detected by microculture tetrazolium assay （MTr）, flow cytometry assay, DNA agarose gel electrophoresis and transmission electronic microscopy. The expressive effect of the wt-p53 in HepG2 cells was analyzed with p53 protein test-reagent. Results JAl not only had significant anti-proliferative effects depending upon time and dosage, but also induced apoptosis of HepG2 cells. Apoptotic typical morphological changes were observed in JAl-treated HepG2 cells under transmission electronic microscope, ＂Sub-G 1＂ phase peak occurred in flow cytometry and DNA ＂ladder＂ was found in DNA agarose gel electrophoresis. The expression of the wt-p53 increased in vitro, and 3Al-treated HepG2 and the positive cell percentage of the wt-p53 protein also increased. Conclusions JAl could obviously induce apoptosis and inhibit proliferation of HepG2 cells in vitro, and these effects are closely related with the increase of wt-p53 expression. JAl can be used as a good source of medicinal plant for the treatment of hepatocarcinoma.
