Objective： Yes Associated Protein （YAP） is a downstream effector that negatively regulated by Hippo kinase LATS1/2. As a transcriptional coactivator, YAP controls the transactivation of variety target genes to prom...Objective： Yes Associated Protein （YAP） is a downstream effector that negatively regulated by Hippo kinase LATS1/2. As a transcriptional coactivator, YAP controls the transactivation of variety target genes to promote cell proliferation which is a critical survival input for cancer cells, thus the inhibition of YAP function is a promising strategy to treat cancer patients. The aim of this study was to explore YAP inhibitors derived from natural products using a cell-based YAP-TEADs luciferase reporter assay and investigate the functional activities of the novel inhibitor. Methods： natural compounds were used by 8×GTIIC luciferase reporter assay to screen YAP inhibitor. Phosphorylation of YAP and AMPK were detected by Western Blotting. The target genes of YAP were determined through RT-PCR. Inhibition on HepG2 cells of screened compounds were assessed by the Sulforhodamine B （SRB） assay. Results： we found that Shikonin （derived from the traditional Chinese medical herb Zicao （Lithospermum erythrorhizon）） exerted significant suppression against the transcriptional activity of YAP （inhibition ratio=74.3%）, accompanied with increased phosphorylation of YAP protein upon within short-exposure to cancer cells. Shikonin treated on HepG2 induced phosphorylation of AMPK. In HepG2 cell lines, Shikonin exhibited a profound cytotoxicity in a concentration manner. Conclusion： our results indicated that the inhibition activity of Shikonin on YAP function was probably due to the activation of AMPK by phosphorylation. Moreover, Shikonin exhibited potent cytotoxicity on cancer cells. In summary, the present study identifies Shikonin as a novel natural inhibitor of YAP function and could be an anti-cancer drug candidate for cancer treatment.展开更多
基金This work was supported National Key R＆D Program of China （No. 2017YFE0102200）, National Natural Science Foundation for Distinguished Young Scholar of China （81625024） and National Natural Science Foundation of China （81773753） to B. Yang.
文摘Objective： Yes Associated Protein （YAP） is a downstream effector that negatively regulated by Hippo kinase LATS1/2. As a transcriptional coactivator, YAP controls the transactivation of variety target genes to promote cell proliferation which is a critical survival input for cancer cells, thus the inhibition of YAP function is a promising strategy to treat cancer patients. The aim of this study was to explore YAP inhibitors derived from natural products using a cell-based YAP-TEADs luciferase reporter assay and investigate the functional activities of the novel inhibitor. Methods： natural compounds were used by 8×GTIIC luciferase reporter assay to screen YAP inhibitor. Phosphorylation of YAP and AMPK were detected by Western Blotting. The target genes of YAP were determined through RT-PCR. Inhibition on HepG2 cells of screened compounds were assessed by the Sulforhodamine B （SRB） assay. Results： we found that Shikonin （derived from the traditional Chinese medical herb Zicao （Lithospermum erythrorhizon）） exerted significant suppression against the transcriptional activity of YAP （inhibition ratio=74.3%）, accompanied with increased phosphorylation of YAP protein upon within short-exposure to cancer cells. Shikonin treated on HepG2 induced phosphorylation of AMPK. In HepG2 cell lines, Shikonin exhibited a profound cytotoxicity in a concentration manner. Conclusion： our results indicated that the inhibition activity of Shikonin on YAP function was probably due to the activation of AMPK by phosphorylation. Moreover, Shikonin exhibited potent cytotoxicity on cancer cells. In summary, the present study identifies Shikonin as a novel natural inhibitor of YAP function and could be an anti-cancer drug candidate for cancer treatment.
