Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.4.2.30 (PARP)
 13,611 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The epipolythiodioxopiperazines (ETPs) are fungal secondary metabolites proven to trigger both apoptotic and necrotic cell death of tumor cells. However, the underlying mechanism of their regulatory role in macroautophagy and the interplay between autophagy and apoptosis initiated by the ETPs, remain unexplored. In the current work, we found that 11'-deoxyverticillin A (C42), a member of the ETPs, induces autophagosome formation, accumulation of microtubule-associated protein 1 light chain 3-II (LC3-II ) and degradation of sequestosome 1 (SQSTM1/p62). In addition, the LC3-II accrual and p62 degradation occur prior to caspase activation and coincide with PARP activation. Inhibition of autophagy by either chemical inhibitors or by RNA interference single knockdown of essential autophagic genes partially reduces the cell death and the cleavage of both caspase 3 and PARP. Necrostatin-1, a specific inhibitor of necroptosis, inhibits both the augmentation of LC3-II and the cleavage of caspase 3, which was confirmed by depletion of receptor-interacting protein 1 (RIP-1), a crucial necrostatin-1-targeted adaptor kinase mediating cell death and survival. Moreover, inhibition of PARP by either chemical inhibitors or RNA interference provides obvious protection for cell viability and suppresses the LC3-II accretion caused by C42 treatment. Interestingly, double silencing of LC3 and p62 completely suppressed PARP cleavage and concurrently and maximally augmented the PAR formation induced by C42. Collectively, we have demonstrated that C42 enhances the cellular autophagic process, which requires both PARP and RIP-1 participation, preceding and possibly augmenting, the caspase-dependent apoptotic cell death.
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PMID:PARP and RIP 1 are required for autophagy induced by 11'-deoxyverticillin A, which precedes caspase-dependent apoptosis. 2146 Jun 25

Recent years, the incidence and mortality of prostate cancer have increased dramatically in China. At earlier stages, most diagnosed prostate cancers are responsive to androgen depletion treatment, yet, nearly all patients will eventually progress to metastatic androgen-independent prostate cancer (AIPC), which still has no effective therapeutic method or drug to deal with. 11'-Deoxyverticillin A (C42) belongs to the family of epipolythiodioxopiperazines (ETPs), an interesting class of fungal toxins that inhibit farnesyl transferase. Compounds holding such a property have been explored as putative anticancer agents. In this study, using PC3M cells, an AIPC cell line, we investigated the effect of the compound on apoptosis and explored the underlying mechanism. It revealed that C42 markedly enhanced the activity of caspase-3/7 and increased the accumulation of the cleaved PARP, all of which are the markers of apoptosis. It also revealed that C42 either decreased cell viability or inhibited the growth of PC3M cells. Moreover, we observed that the loss of cell viability and cell growth inhibition induced by C42 were both time- and dosage dependent. Taken together, we indicated that C42 can induce caspase-dependent apoptosis in AIPC cells, and the results presented here will broaden our knowledge about the molecular mechanisms by which C42 exerts its anticancer activity, and future work in this direction may provide valuable information in the development of these compounds into effective cancer therapeutic strategies against androgen-independent prostate cancer.
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PMID:[11'-Deoxyverticillin A induces caspase-dependent cell apoptosis in PC3M cells]. 2266 13