Studies on p53 and Bax protein expression in Cockayne syndrome cells after UV irradiation and interferon-beta treatment.
Human interferon (HuIFN) has a protective effect against ultraviolet (UV)-induced killing of Cockayne syndrome (CS) and xeroderma pigmentosum (XP) cells. Irradiation with ultraviolet (UV) resulted in nuclear accumulation of p53 in normal human fibroblast cells, and this accumulation was suppressed by treatment with HuIFN-beta. On the other hand, a large amount of p53 was found in both nuclear and cytoplasmic fractions of one SV40-transformed XP and two SV40-transformed CS cell strains irrespective of UV irradiation. Treatment with HuIFN-beta reduced the level of pro-apoptotic Bax protein without suppression of nuclear accumulation of p53 in the CS cells but not in the XP cells. These findings suggest that there are different mechanisms of UV-refractoriness caused by HuIFN-beta in UV-sensitive CS and XP cells.
Sugita
K
K
Department of Clinical Medicine, Faculty of Education, Chiba University, Yayoi 1-33, Inage-ku, Chiba 263-8522, Japan. sugita@med.m.chiba-u.ac.jp
Chi
X J
XJ
Hiwasa
T
T
Suzuki
N
N
D000328:Adult; D015153:Blotting, Western; D002461:Cell Line, Transformed; D002470:Cell Survival / Q000528:radiation effects; D003057:Cockayne Syndrome / Q000378:metabolism*; D004307:Dose-Response Relationship, Radiation; D005347:Fibroblasts; D015870:Gene Expression / Q000528:radiation effects; D006801:Humans; D016899:Interferon-beta / Q000494:pharmacology*; D008297:Male; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism; D011836:Radiation Tolerance / Q000235:genetics*; D013539:Simian virus 40 / Q000502:physiology; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism*; D014466:Ultraviolet Rays; D014983:Xeroderma Pigmentosum / Q000235:genetics*; D051028:bcl-2-Associated X Protein
C494826:BAX protein, human; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53; D051028:bcl-2-Associated X Protein; D016899:Interferon-beta