Lewis Jean McArthur, Truong Tony Nguyen, Schwartz Martin Alexander
Department of Vascular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, CVN228/VB4, La Jolla, CA 92037, USA.
Proc Natl Acad Sci U S A. 2002 Mar 19;99(6):3627-32. doi: 10.1073/pnas.062698499.
p53 mediates apoptosis of cells after DNA damage including tumor cells after radiation or chemotherapy. Survival of isolated cancer cells after therapy leads to recurrence of therapy-resistant tumors. We now show that for some melanoma, sarcoma, or fibroblastic cell types that survive without integrin-mediated adhesion, apoptosis in response to DNA damage requires cell adhesion. This effect correlates with rapid changes in levels of p14/p19 Arf and its downstream component, p53. Killing of nonadherent cells is increased by treatment with antiintegrin antibodies or by increasing levels of p53 or Arf. Consistent with low p53 levels, suspended cells show chromosomal instability after irradiation. Thus, loss of normal adhesion in susceptible tumor cells during genotoxic stress may play a role in therapy resistance and promote survival of cells with aberrant DNA.
p53介导DNA损伤后细胞的凋亡,包括放疗或化疗后的肿瘤细胞。治疗后分离的癌细胞存活会导致抗治疗性肿瘤复发。我们现在表明,对于一些在没有整合素介导的黏附情况下仍能存活的黑色素瘤、肉瘤或成纤维细胞类型,DNA损伤后的凋亡需要细胞黏附。这种效应与p14/p19 Arf及其下游成分p53水平的快速变化相关。用抗整合素抗体治疗或提高p53或Arf水平可增加对非黏附细胞的杀伤。与低p53水平一致,悬浮细胞在照射后表现出染色体不稳定。因此,在基因毒性应激期间,易感肿瘤细胞正常黏附的丧失可能在治疗抗性中起作用,并促进DNA异常细胞的存活。