INHIBITORY EFFECT OF PROBUCOL ON BENZO[A]PYRENE INDUCED LUNG TUMORIGENESIS

The effects of probucol, a clinically used cholesterol lowering and an tioxidant drug, on benzo[a]pyrene (B[a]P) induced pulmonary and forest omach tumorigenesis as well as induction of colonic aberrant crypt foc i (ACF) in female A/J mice was investigated, Diet containing 1% probuc ol fed prior to, during and after 8 bi-weekly 1 mg/mouse oral intubati ons of B[a]P, reduced the number of pulmonary adenomas by 52% (P < 0.0 01) and the number of forestomach tumors by 31%. The 0.06% probucol di et also resulted in decreased tumor formation but the differences did not reach statistical significance, Both probucol diets significantly reduced the numbers of large ACF, putative preneoplastic lesions of th e colon mucosa, but showed no effects on the total numbers of ACF, The results of this study suggest that probucol may also be useful as a c hemopreventive agent, in addition to being a cholesterol lowering and anti-atherogenic drug with low toxicity.