Casticin Induced Apoptosis in A375.S2 Human Melanoma Cells through the Inhibition of NF-[Formula: see text]B and Mitochondria-Dependent Pathways In Vitro and Inhibited Human Melanoma Xenografts in a Mouse Model In Vivo.
Casticin, a polymethoxyflavone occurring in natural plants, has been shown to have anticancer activities. In the present study, we aims to investigate the anti-skin cancer activity of casticin on melanoma cells in vitro and the antitumor effect of casticin on human melanoma xenografts in nu/nu mice in vivo. A flow cytometric assay was performed to detect expression of viable cells, cell cycles, reactive oxygen species production, levels of [Formula: see text] and caspase activity. A Western blotting assay and confocal laser microscope examination were performed to detect expression of protein levels. In the in vitro studies, we found that casticin induced morphological cell changes and DNA condensation and damage, decreased the total viable cells, and induced G2/M phase arrest. Casticin promoted reactive oxygen species (ROS) production, decreased the level of [Formula: see text], and promoted caspase-3 activities in A375.S2 cells. The induced G2/M phase arrest indicated by the Western blotting assay showed that casticin promoted the expression of p53, p21 and CHK-1 proteins and inhibited the protein levels of Cdc25c, CDK-1, Cyclin A and B. The casticin-induced apoptosis indicated that casticin promoted pro-apoptotic proteins but inhibited anti-apoptotic proteins. These findings also were confirmed by the fact that casticin promoted the release of AIF and Endo G from mitochondria to cytosol. An electrophoretic mobility shift assay (EMSA) assay showed that casticin inhibited the NF-[Formula: see text]B binding DNA and that these effects were time-dependent. In the in vivo studies, results from immuno-deficient nu/nu mice bearing the A375.S2 tumor xenograft indicated that casticin significantly suppressed tumor growth based on tumor size and weight decreases. Early G2/M arrest and mitochondria-dependent signaling contributed to the apoptotic A375.S2 cell demise induced by casticin. In in vivo experiments, A375.S2 also efficaciously suppressed tumor volume in a xenotransplantation model. Therefore, casticin might be a potential therapeutic agent for the treatment of skin cancer in the future.
* Department of Biological Science and Technology, China Medical University Taichung 404, Taiwan.
Yin-Wen
YW
Shiue
† School of Nutrition and Health Sciences, Taipei Medical University, Taipei 11031, Taiwan.
Chi-Cheng
CC
Lu
‡ Institute of Medicine, Chung Shan Medical University, Taichung 402, Taiwan.|§ Department of Dermatology, Chung Shan Medical University Hospital Taichung 402, Taiwan.
Yu-Ping
YP
Hsiao
¶ Graduate Institute of Chinese Medicine, China Medical University, Taichung 404, Taiwan.
Ching-Lung
CL
Liao
∥ School of Chinese Medicine, China Medical University, Taichung 404, Taiwan.
Jing-Pin
JP
Lin
** School of Medicine, China Medical University, Taichung 404, Taiwan.|†† Department of Surgery, China Medical University Beigang Hospital, Yunlin 651, Taiwan.
Kuang-Chi
KC
Lai
‡‡ School of Pharmacy, China Medical University, Taichung 404, Taiwan.
Chien-Chih
CC
Yu
§§ Department of Physiology, China Medical University, Taichung 404, Taiwan.
Yi-Ping
YP
Huang
** School of Medicine, China Medical University, Taichung 404, Taiwan.
Heng-Chien
HC
Ho
* Department of Biological Science and Technology, China Medical University Taichung 404, Taiwan.|¶¶ Department of Biotechnology, Asia University, Taichung 413, Taiwan.
Jing-Gung
JG
Chung
D000818:Animals; D000972:Antineoplastic Agents, Phytogenic; D017209:Apoptosis / Q000187:drug effects* / Q000235:genetics*; D020169:Caspases / Q000378:metabolism; D004195:Disease Models, Animal; D005419:Flavonoids / Q000494:pharmacology* / Q000627:therapeutic use*; D059565:G2 Phase Cell Cycle Checkpoints / Q000187:drug effects / Q000235:genetics; D064593:Heterografts; D006801:Humans; D008545:Melanoma / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D051379:Mice; D008819:Mice, Nude; D008928:Mitochondria; D016328:NF-kappa B; D009368:Neoplasm Transplantation; D009360:Neoplastic Cells, Circulating; D008517:Phytotherapy; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction; D012878:Skin Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism / Q000473:pathology*
D000972:Antineoplastic Agents, Phytogenic; D005419:Flavonoids; D016328:NF-kappa B; D017382:Reactive Oxygen Species; C054133:casticin; D020169:Caspases
A375.S2 Human Skin Cancer Cells; Apoptosis; Casticin; Mitochondria Dysfunction; NF-B; Xenograft Tumor