title: Design and synthesis of a C7-aryl piperlongumine derivative with potent antimicrotubule and mutant p53-reactivating properties.
abstract: Small molecules that can restore biological function to the p53 mutants found in human cancers have been highly sought to increase the anticancer efficacy. In efforts to generate hybrid anticancer drugs that can impact two or more targets simultaneously, we designed and developed piperlongumine (PL) derivatives with an aryl group inserted at the C-7 position. This insertion bestowed a combretastatin A4 (CA4, an established microtubule disruptor) like structure while retaining the piperlongumine configuration. The new compounds exhibited potent antiproliferative activities against eight cancer cell lines, in particular, were more cytotoxic against the SKBR-3 breast cancer cells which harbor a R175H mutation in p53 suppressor. KSS-9, a representative aryl PL chosen for further studies induced abundant ROS generation and protein glutathionylation. KSS-9 strongly disrupted the tubulin polymerization in vitro, destabilized the microtubules in cells and induced a potent G2/M cell cycle block. More interestingly, KSS-9 showed the ability to reactivate the p53 mutation and restore biological activity to the R175H mutant protein present in SKBR3 cells. Several procedures, including immunocytochemistry using conformation-specific antibodies for p53, immunoprecipitation combined with western blotting, electrophoretic shift mobility shift assays showed a reciprocal loss of mutant protein and generation of wild-type like protein. p53 reactivation was accompanied by the induction of the target genes, MDM2, p21cip1 and PUMA. Mechanistically, the redox-perturbation in cancer cells by the hybrid drug appears to underlie the p53 reactivation process. This anticancer drug approach merits further development.
authors.affiliation: Department of Biomedical Sciences and Cancer Biology Center, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX 79106, USA.
authors.forename: Surendra R
authors.initials: SR
authors.lastname: Punganuru
authors.affiliation: Department of Biomedical Sciences and Cancer Biology Center, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX 79106, USA.
authors.forename: Hanumantha Rao
authors.initials: HR
authors.lastname: Madala
authors.affiliation: Department of Biomedical Sciences and Cancer Biology Center, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX 79106, USA.
authors.forename: Sanjay N
authors.initials: SN
authors.lastname: Venugopal
authors.affiliation: Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX 79106, USA.
authors.forename: Ramakrishna
authors.initials: R
authors.lastname: Samala
authors.affiliation: Department of Biomedical Sciences and Cancer Biology Center, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX 79106, USA.
authors.forename: Constantinos
authors.initials: C
authors.lastname: Mikelis
authors.affiliation: Department of Biomedical Sciences and Cancer Biology Center, School of Pharmacy, Texas Tech University Health Sciences Center, Amarillo, TX 79106, USA. Electronic address: Kalkunte.Srivenugopal@ttuihsc.edu.
authors.forename: Kalkunte S
authors.initials: KS
authors.lastname: Srivenugopal
mesh_terms: D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000473:pathology; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D060326:Chemistry Techniques, Synthetic; D004148:Dioxolanes / Q000737:chemistry*; D015195:Drug Design; D005260:Female; D016147:Genes, Tumor Suppressor; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D008870:Microtubules / Q000187:drug effects* / Q000378:metabolism; D009154:Mutation; D017382:Reactive Oxygen Species / Q000378:metabolism; D013267:Stilbenes / Q000737:chemistry; D016159:Tumor Suppressor Protein p53 / Q000235:genetics* / Q000378:metabolism; D010881:Piperidones
chemical_list: D000970:Antineoplastic Agents; D004148:Dioxolanes; D005978:Glutathione; D017382:Reactive Oxygen Species; D013267:Stilbenes; D016159:Tumor Suppressor Protein p53; C495901:TP53 protein, human; C498077:piperlongumine; D010881:Piperidones; C058728:fosbretabulin
keywords: Cancer chemotherapy; Combretastatin-A4; Hybrid drugs; Oxidative stress; Protein glutathionylation