title: Icaritin activates JNK-dependent mPTP necrosis pathway in colorectal cancer cells.
abstract: The colorectal cancer (CRC) is one leading contributor of cancer-related mortality worldwide. The search for effective anti-CRC agents is valuable. In the current study, we showed that icaritin (ICT), an active natural ingredient from the Chinese plant Epimedium, potently inhibited proliferation and survival of established (HT-29, HCT-116, DLD-1, and SW-620) and primary (patient-derived) CRC cells. Significantly, ICT mainly induced necrosis, but not apoptosis, in CRC cells. The necrosis inhibitor necrostatin-1 attenuated ICT-mediated cytotoxicity in CRC cells. We showed that ICT treatment in CRC cells induced mitochondrial permeability transition pore (mPTP) opening, which was evidenced by mitochondrial membrane potential (MMP) decrease and mitochondrial adenine nucleotide translocator-1 (ANT-1)-cyclophilin-D (CyPD) association. On the other hand, mPTP blockers, including sanglifehrin A, cyclosporin A, and bongkrekic acid, as well as siRNA-mediated knockdown of mPTP component (CyPD or ANT-1), significantly alleviated ICT-mediated cytotoxicity against CRC cells. We suggested that Jun-N-terminal kinase (JNK) activation by ICT mediated mPTP opening and subsequent CRC cell necrosis. JNK pharmacological inhibition, dominant negative mutation, or shRNA downregulation suppressed ICT-induced MMP reduction and subsequent HT-29 cell necrosis. In vivo, oral gavage of ICT dramatically inhibited HT-29 xenograft growth in nude mice. The in vivo activity by ICT was largely attenuated by co-administration with the mPTP blocker CsA. Collectively, our results showed that ICT exerts potent inhibitory effect against CRC cells in vitro and in vivo. JNK-dependent mPTP necrosis pathway could be key mechanism responsible for ICT's actions.
authors.affiliation: Department of Interventional Radiology, WuJiang Hospital Affiliated to Nantong University, No. 169 Park Road, Songling Town, WuJiang, Suzhou, 215200, China.
authors.forename: Chunxian
authors.initials: C
authors.lastname: Zhou
authors.affiliation: Department of General Surgery, The Second Affiliated Hospital of Soochow University, Suzhou, 215000, China.
authors.forename: Zhengrong
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Department of Hepatobiliary Surgery of Suzhou Municipal Hospital, Suzhou, 215000, China.
authors.forename: Xingsheng
authors.initials: X
authors.lastname: Lu
authors.affiliation: Department of Interventional Radiology, WuJiang Hospital Affiliated to Nantong University, No. 169 Park Road, Songling Town, WuJiang, Suzhou, 215200, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Wu
authors.affiliation: Department of Interventional Radiology, WuJiang Hospital Affiliated to Nantong University, No. 169 Park Road, Songling Town, WuJiang, Suzhou, 215200, China.
authors.forename: Qunying
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Department of Interventional Radiology, WuJiang Hospital Affiliated to Nantong University, No. 169 Park Road, Songling Town, WuJiang, Suzhou, 215200, China. drxudongfeng6@126.com.
authors.forename: Dongfeng
authors.initials: D
authors.lastname: Xu
mesh_terms: D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000473:pathology; D005419:Flavonoids / Q000494:pharmacology*; D045325:HCT116 Cells; D019073:HT29 Cells; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases / Q000502:physiology*; D051379:Mice; D033681:Mitochondrial Membrane Transport Proteins / Q000187:drug effects* / Q000502:physiology; D000083162:Mitochondrial Permeability Transition Pore; D009336:Necrosis
chemical_list: D005419:Flavonoids; D033681:Mitochondrial Membrane Transport Proteins; D000083162:Mitochondrial Permeability Transition Pore; D048031:JNK Mitogen-Activated Protein Kinases; C499403:icaritin
keywords: Colorectal cancer; Icaritin (ICT); JNK and necrosis; mPTP