title: Growth suppression induced by antitumor drug vitamin K-3 in human hepatoma HepG2 cells is accompanied by downregulation of proliferating cell nuclear antigen expression.
abstract: The effects of VK3 on the expression of proliferating cell nuclear antigen (PCNA) and tumor suppresser p53 were investigated in human hepatoma HEPG2 cells. VK3 (50-250 mu M) for 3 h-treatment, induced 2- to 5-fold increase in PCNA mRNA. Cells treated with 100 mu M of VK3 for 0-8 h, showed PCNA mRNA initially increased but subsequently decreased. PCNA protein decreased in 75-100 mu M VK3-treated asynchronous cells but decreased slightly in 100 mu M VK3-treated synchronized cells. p53 protein increased 2-fold in VK3-treated synchronized cells. No changes in PCNA were noted with coincubation of VK3 and actinomycin D, alpha-amanitin, or cycloheximide. This evidence shows that VK3-induced cell growth inhibition and cell cycling events are accompanied by down-regulation of PCNA protein expression.
authors.forename: C
authors.initials: C
authors.lastname: Juan
authors.forename: F
authors.initials: F
authors.lastname: Wu