Xing Sun1, Wang Liao2, Jialing Wang3, Ping Wang4, Hongxiu Gao4, Meng Wang4, Chunling Xu4, Yaping Zhong4, Yan Ding5. 1. College of Life Sciences, Sichuan University, Chengdu, Sichuan, 610064, PR China. 2. Department of Cardiology, Hainan General Hospital, Haikou, Hainan, 570102, PR China. 3. School of Foreign Languages and Literature, Wuhan University, Wuhan, Hubei, 430072, PR China. 4. Department of Hematology, Zhumadian Central Hospital, Zhumadian, Henan 463000, PR China. 5. Department of Dermatology, Maternal and Child Health Care Hospital of Hainan Province, Haikou, Hainan, 570206, PR China. Electronic address: dingyanhn@163.com.
Abstract
BACKGROUND: The natural product tetramethylpyrazine (TMP) and resveratrol have a variety of biologic activities, including anti-cancer effects. However the pharmacological function of CSTMP (a newly designed and synthesized TMP and resveratrol derivative) in cancer have not been elucidated. METHODS: In RPMI8226 cells, the cytotoxic effects and apoptosis were detected by MTT and Double staining for Annexin V-FITC and propidium iodide (PI). The protein and mRNA expression levels were detected by Real Time PCR and Western blot, respectively. The localization of cleaved caspase-12 was evaluated by immunofluorescent staining. The activation of caspase were measured by colorimetric assays and Western blot. RESULTS: CSTMP showed significantly cytotoxic effects and induced apoptosis in RPMI8226 cells. Caspase activation, Cytochrome c release and Bax, Bcl-2 and Bcl-XL levels analyses demonstrated that the anti-cancer effect of CSTMP in RPMI8226 cells was mediated by promoting caspase- and mitochondria-dependent apoptosis. In addition, CSTMP induced the increased expression of endoplasmic reticulum (ER) stress related proteins (CHOP, GRP78, GRP94 and cleaved caspase-12) and the activation of multiple branches of ER stress transducers (PERK-eIF2α, IRE1α and ATF6). Moreover, knockdown of CHOP by siRNA markedly inhibited CSTMP-induced cytotoxic effects, caspases activity and mitochondrial dysfunction in RPMI8226 cells. CONCLUSIONS: Our results indicated that CSTMP could induce apoptosis and mitochondrial dysfunction in RPMI8226 cells via CHOP-dependent ER stress.
BACKGROUND: The natural product tetramethylpyrazine (TMP) and resveratrol have a variety of biologic activities, including anti-cancer effects. However the pharmacological function of CSTMP (a newly designed and synthesized TMP and resveratrol derivative) in cancer have not been elucidated. METHODS: In RPMI8226 cells, the cytotoxic effects and apoptosis were detected by MTT and Double staining for Annexin V-FITC and propidium iodide (PI). The protein and mRNA expression levels were detected by Real Time PCR and Western blot, respectively. The localization of cleaved caspase-12 was evaluated by immunofluorescent staining. The activation of caspase were measured by colorimetric assays and Western blot. RESULTS: CSTMP showed significantly cytotoxic effects and induced apoptosis in RPMI8226 cells. Caspase activation, Cytochrome c release and Bax, Bcl-2 and Bcl-XL levels analyses demonstrated that the anti-cancer effect of CSTMP in RPMI8226 cells was mediated by promoting caspase- and mitochondria-dependent apoptosis. In addition, CSTMP induced the increased expression of endoplasmic reticulum (ER) stress related proteins (CHOP, GRP78, GRP94 and cleaved caspase-12) and the activation of multiple branches of ER stress transducers (PERK-eIF2α, IRE1α and ATF6). Moreover, knockdown of CHOP by siRNA markedly inhibited CSTMP-induced cytotoxic effects, caspases activity and mitochondrial dysfunction in RPMI8226 cells. CONCLUSIONS: Our results indicated that CSTMP could induce apoptosis and mitochondrial dysfunction in RPMI8226 cells via CHOP-dependent ER stress.