Hairless Mice for Carcinogenesis Studies.
NIOSH 1982 Apr:671-686
The susceptibility to ultraviolet (UV) ray induced skin cancer was studied in groups of hairless mice with similar anatomic features but different genetic backgrounds. Animals received daily whole body exposures to UV in doses designed for either high yield studies or dose/response studies. In the high yield study group the doses were high enough to produce a perceptible response such as edema, flaking and hyperplasia but did not produce ulceration and wound healing phenomena over a 6 month period. The results of the high yield studies offered some striking differences in the tumor response among the various stocks and strains of mice tested. Generally, albino-mice tended to be more susceptible to UV induced cancer than those with some melanocytic activity. In the dose/response groups each strain was exposed to four different daily doses over a range of 18 to 50 percent of the doses used in the high yield group. In the dose/response groups, response curves were derived for each of the four doses given for each genetic group and these four lines tended to be parallel. The time to 50 percent incidence for each of the curves was examined for the most sensitive of the hairless lines tested, the least sensitive, and one intermediate degree of sensitivity. Plotting the reciprocal of each value against weeks in the experiment suggests that the differential sensitivities of these animal lines are represented by proportional offsets, and that the slopes of the responses are parallel. The results of immunology testing indicated that the animals tested have the type of immunologic response one would associate with normal mice, and that if there is an immunologic association to tumor susceptibility, the effect is too subtle to be detected by these evaluations.
Laboratory-animals; Skin-exposure; Cancer-rates; Risk-analysis; Ultraviolet-radiation; Ultraviolet-light; Nonionizing-radiation;
Proceedings of the Second NCI/EPA/NIOSH Collaborative Workshop: Progress on Joint Environmental and Occupational Cancer Studies, September 9-11, 1981, Rockville, Maryland