L. Cifaldi et al., A light, nontoxic interleukin 12 protocol inhibits HER-2/neu mammary carcinogenesis in BALB/c transgenic mice with established hyperplasia, CANCER RES, 61(7), 2001, pp. 2809-2812
With a slight asynchronous but consistent progression, all of the mammary g
lands of female BALB/c mice transgenic for the transforming rat HER-2/neu o
ncogene progress to atypical hyperplasia and to invasive carcinoma. Previou
s studies have shown that chronic administration of interleukin (IL) 12 sta
rted at the 2nd week of age hampers this progression because of its ability
to inhibit tumor angiogenesis and activate a nonspecific immune response.
Here we show that a similar inhibition is achieved when 7-week-old mice wit
h fully blown atypical hyperplasia receive a weekly injection of 100 ng IL-
12 for 16 times. This lower-dose and later IL-12 administration induces hig
h and sustained levels of serum IFN-gamma equivalent to those elicited by m
ore frequent administrations. A lower-dose and less toxic treatment may thu
s be envisaged as a possible option in the management of preneoplastic mamm
ary lesions.