Location of Repository

Advances in Brief p53 Is Involved in But Not Required for Ionizing Radiation-induced Caspase-3

By Human Lymphoblast, Cell Lines, Yongjia Yu and John B. LittleContact The Aacr Publications, Apoptosis Human, Lymphoblast Cell Lines and John B. Little

Abstract

The caspase-3 has been shown to be involved in mediating apoptosis induced by different stimuli. However, it is still unclear whether p53 is required for the ionizing radiation (IR)-induced caspase-3 activation. In the present study, we examined IR-induced apoptosis in three closely related human lymphoblast cell lines that differ in p53 status. Irradiation of TK6 cells (wild-type/>53) with 4 Gy y-rays resulted in rapid apoptosis, whereas the apoptotic response was delayed and reduced in WTK1 cells (mutant pS3) and the TK6 derivative line expressing HPV16 E6 (abrogat ed p53). The differential apoptotic responses in these cell lines correlated with caspase-3 activation. IR induced an early as well as a late phase of caspase-3 activation in TK6 but only a delayed onset ¡nWTK1 and TK6-E6-5E cells. The early phase of caspase-3 activation coincided with an elevation of p53 and bax protein levels. Pretreatment of all three cell lines with a caspases inhibitor z-VAD-FMK inhibited apoptosis. Thes

Year: 2013
OAI identifier: oai:CiteSeerX.psu:10.1.1.320.3604
Provided by: CiteSeerX
Download PDF:
Sorry, we are unable to provide the full text but you may find it at the following location(s):
  • http://citeseerx.ist.psu.edu/v... (external link)
  • http://cancerres.aacrjournals.... (external link)
  • Suggested articles


    To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.