title: Coumarin-chalcone hybrid instigates DNA damage by minor groove binding and stabilizes p53 through post translational modifications.
abstract: S009-131, a coumarin-chalcone hybrid, had been shown to possess anti-proliferative and anti-tumour effect by triggering apoptosis. In this report, we investigated role of DNA damage signalling pathway in S009-131 induced cancer cell death. Here we show that S009-131 causes DNA damage by potential binding to the minor groove which led to the phosphorylation and activation of ATM and DNA-PK, but not ATR, at earlier time points in order to initiate repair process. S009-131 induced DNA damage response triggered activation of p53 through phosphorylation at its key residues. Pharmacological inhibition of PIKKs abrogated S009-131 induced phosphorylation of p53 at Ser 15. DNA damage induced phosphorylation resulted in reduced proteasomal degradation of p53 by disrupting p53-MDM2 interaction. Additionally, our docking studies revealed that S009-131 might also contribute to increased cellular p53 level by occupying p53 binding pocket of MDM2. Posttranslational modifications of p53 upon S009-131 treatment led to enhanced affinity of p53 towards responsive elements (p53-RE) in the promoter regions of target genes and increased transcriptional efficiency. Together, the results suggest that S009-131 cleaves DNA through minor groove binding and eventually activates PIKKs associated DNA damage response signalling to promote stabilization and enhanced transcriptional activity of p53 through posttranslational modifications at key residues.
authors.affiliation: Biochemistry Division, CSIR-Central Drug Research Institute, Sector-10, Jankipuram Extension, Lucknow, 226 031, India.
authors.forename: Raghib
authors.initials: R
authors.lastname: Ashraf
authors.affiliation: Endocrinology Division, CSIR-Central Drug Research Institute, Sector-10, Jankipuram Extension, Lucknow, 226 031, India.
authors.lastname: Hamidullah
authors.affiliation: Biochemistry Division, CSIR-Central Drug Research Institute, Sector-10, Jankipuram Extension, Lucknow, 226 031, India.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Hasanain
authors.affiliation: Biochemistry Division, CSIR-Central Drug Research Institute, Sector-10, Jankipuram Extension, Lucknow, 226 031, India.
authors.forename: Praveen
authors.initials: P
authors.lastname: Pandey
authors.affiliation: Biochemistry Division, CSIR-Central Drug Research Institute, Sector-10, Jankipuram Extension, Lucknow, 226 031, India.
authors.forename: Mayank
authors.initials: M
authors.lastname: Maheshwari
authors.affiliation: Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, Sector-10, Jankipuram Extension, Lucknow, 226 031, India.
authors.forename: L Ravithej
authors.initials: LR
authors.lastname: Singh
authors.affiliation: KS # 101, Tata Memorial Centre, Advanced Centre for Treatment, Research and Education in Cancer, Kharghar, Navi Mumbai, 410 210, India.
authors.forename: M Quadir
authors.initials: MQ
authors.lastname: Siddiqui
authors.affiliation: Endocrinology Division, CSIR-Central Drug Research Institute, Sector-10, Jankipuram Extension, Lucknow, 226 031, India.|Academy of Scientific and Innovative Research, Chennai, 600113, India.
authors.forename: Rituraj
authors.initials: R
authors.lastname: Konwar
authors.affiliation: Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, Sector-10, Jankipuram Extension, Lucknow, 226 031, India.|Academy of Scientific and Innovative Research, Chennai, 600113, India.
authors.forename: Koneni V
authors.initials: KV
authors.lastname: Sashidhara
authors.affiliation: Biochemistry Division, CSIR-Central Drug Research Institute, Sector-10, Jankipuram Extension, Lucknow, 226 031, India.|Academy of Scientific and Innovative Research, Chennai, 600113, India.
authors.forename: Jayanta
authors.initials: J
authors.lastname: Sarkar
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D064007:Ataxia Telangiectasia Mutated Proteins / Q000378:metabolism; D001665:Binding Sites / Q000187:drug effects; D059447:Cell Cycle Checkpoints / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D047188:Chalcones / Q000494:pharmacology*; D003374:Coumarins / Q000494:pharmacology*; D004247:DNA / Q000737:chemistry*; D004249:DNA Damage / Q000187:drug effects*; D004260:DNA Repair / Q000187:drug effects; D045325:HCT116 Cells; D006657:Histones / Q000378:metabolism; D006801:Humans; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D011401:Promoter Regions, Genetic / Q000235:genetics; D046188:Protein Modification, Translational / Q000187:drug effects*; D051736:Proto-Oncogene Proteins c-mdm2 / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000235:genetics*; D054875:Ubiquitination / Q000187:drug effects
chemical_list: D000970:Antineoplastic Agents; D047188:Chalcones; D003374:Coumarins; C468783:H2AX protein, human; D006657:Histones; D016159:Tumor Suppressor Protein p53; C000593365:ethyl 8-sec-butyl-2-oxo-6-(3-oxo-3-p-tolylprop-1-enyl)-2H-chromene-3-carboxylate; D004247:DNA; C497206:MDM2 protein, human; D051736:Proto-Oncogene Proteins c-mdm2; D019869:Phosphatidylinositol 3-Kinases; C576324:ATM protein, human; C576597:ATR protein, human; D064007:Ataxia Telangiectasia Mutated Proteins