Influence of ionizing radiation on induction of apoptotic cell death and cellular redistribution of protein kinase C isozymes in mouse epidermal cells differing in carcinogenesis stages.
Although protein kinase C (PKC) plays an important role in cellular response to radiation, little is known about the specific role of each isoform in the radiation induced cellular response. In this study, the induction of apoptosis and subcellular distribution of PKC isoforms after gamma-ray irradiation were examined in three kinds of mouse epidermal cells with different stages of carcinogenesis (normal mouse keratinocytes, PK: v-rasHa transfected mouse keratinocytes, ras-PK; and neoplastic cells from mouse skin papilloma, 308 cells). The induction of apoptosis was different in normal and neoplastic cells; in normal cells after 16 Gy of radiation, apoptosis was 2-10 times higher than that in ras-PK or 308 cells, and was rapidly induced; other cells died more slowly, depending on the stage of carcinogenesis. The responses of each PKC, especially rapid translocation of PKCdelta and no response of PKCepsilon by radiation in normal cells may influence the induction of apoptosis by radiation.
D000818:Animals; D017209:Apoptosis / Q000528:radiation effects*; D001692:Biological Transport; D002471:Cell Transformation, Neoplastic; D000078404:Epidermal Cells; D004817:Epidermis / Q000201:enzymology / Q000528:radiation effects*; D020287:In Situ Nick-End Labeling; D007527:Isoenzymes / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D011493:Protein Kinase C / Q000378:metabolism*; D013347:Subcellular Fractions / Q000201:enzymology