title: Silver-based nanoparticles induce apoptosis in human colon cancer cells mediated through p53.
abstract: OBJECTIVE
  The authors have systematically investigated the anticancer potentiality of silver-based nanoparticles (AgNPs) and the mechanism underlying their biological activity in human colon cancer cells.
  
  
  METHODS
  Starch-capped AgNPs were synthesized, characterized and their biological activity evaluated through multiple biochemical assays.
  
  
  RESULTS
  AgNPs decreased the growth and viability of HCT116 colon cancer cells. AgNP exposure increased apoptosis, as demonstrated by an increase in 4´,6-diamidino-2-phenylindole-stained apoptotic nuclei, BAX/BCL-XL ratio, cleaved poly(ADP-ribose) polymerase, p53, p21 and caspases 3, 8 and 9, and by a decrease in the levels of AKT and NF-κB. The cell population in the G1 phase decreased, and the S-phase population increased after AgNP treatment. AgNPs caused DNA damage and reduced the interaction between p53 and NF-κB. Interestingly, no significant alteration was noted in the levels of p21, BAX/BCL-XL and NF-κB after AgNP treatment in a p53-knockout HCT116 cell line.
  
  
  CONCLUSIONS
  AgNPs are bona fide anticancer agents that act in a p53-dependent manner. Original submitted 16 March 2012; Revised submitted 25 August 2012; Published online 21 March 2013.
authors.affiliation: Cancer Biology Division, KIIT School of Biotechnology, KIIT University, Campus-11, Patia, Bhubaneswar, Orissa 751024, India.
authors.forename: Shakti Ranjan
authors.initials: SR
authors.lastname: Satapathy
authors.forename: Purusottam
authors.initials: P
authors.lastname: Mohapatra
authors.forename: Ranjan
authors.initials: R
authors.lastname: Preet
authors.forename: Dipon
authors.initials: D
authors.lastname: Das
authors.forename: Biplab
authors.initials: B
authors.lastname: Sarkar
authors.forename: Tathagata
authors.initials: T
authors.lastname: Choudhuri
authors.forename: Michael D
authors.initials: MD
authors.lastname: Wyatt
authors.forename: Chanakya Nath
authors.initials: CN
authors.lastname: Kundu
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000096:biosynthesis; D003110:Colonic Neoplasms / Q000188:drug therapy* / Q000473:pathology; D004249:DNA Damage / Q000187:drug effects; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D045325:HCT116 Cells; D006801:Humans; D053768:Metal Nanoparticles / Q000008:administration & dosage / Q000737:chemistry; D016328:NF-kappa B / Q000096:biosynthesis; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis; D012834:Silver / Q000008:administration & dosage* / Q000737:chemistry; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
chemical_list: D016328:NF-kappa B; D019253:Proto-Oncogene Proteins c-bcl-2; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; D012834:Silver; D053148:Caspase 3