title: Can prenatal X-irradiation in mice act as an initiator stimulus in a modified 2-stage Berenblum/Mottram experiment with postnatal promotion with phorbol ester TPA?
abstract: Long-term animal experiments with prenatally X-irradiated offspring have so far not unequivocally settled the question of elevated tumor susceptibility. We have pursued this problem further in a modified 2-stage carcinogenesis-Berenblum/Mottram experiment. Prenatal X-irradiation of mice has thus been regarded as a possible initiator stimulus, with a postnatal promotion stimulus being given by applying the phorbol ester TPA to the offsprings' skin. This treatment has, however, not produced a higher tumor yield, neither of the skin nor of the internal organs, than that produced by X-irradiation in utero alone. This failure seems partly due to the dysplastic nature of the epidermis of prenatally X-irradiated mice, which also fails to respond to TPA application by way of hyperplasia or by an increased inflammation tendency and ulcer formation. We suggest that a decrease in prostaglandin synthesis after prenatal X-irradiation is an important factor for the unchanged tumor susceptibility, especially of the skin.
mesh_terms: D000236:Adenoma / Q000453:epidemiology; D000818:Animals; D006528:Carcinoma, Hepatocellular / Q000453:epidemiology; D003043:Cocarcinogenesis; D005260:Female; D005333:Fetus / Q000528:radiation effects*; D007938:Leukemia / Q000453:epidemiology; D008113:Liver Neoplasms / Q000453:epidemiology; D008175:Lung Neoplasms / Q000453:epidemiology; D008431:Maternal-Fetal Exchange; D051379:Mice; D010049:Ovarian Diseases / Q000453:epidemiology; D010704:Phorbols / Q000633:toxicity*; D011247:Pregnancy; D011453:Prostaglandins / Q000096:biosynthesis; D011839:Radiation, Ionizing; D012867:Skin / Q000528:radiation effects*; D012878:Skin Neoplasms / Q000139:chemically induced; D013755:Tetradecanoylphorbol Acetate / Q000633:toxicity*; D014965:X-Rays
chemical_list: D010704:Phorbols; D011453:Prostaglandins; D013755:Tetradecanoylphorbol Acetate