Responses of experimental rat tumours and a mouse colon tumour to flavone acetic acid

Abstract

The toxicity in rats and mice and the responses of 5 rat lung tumours, a rat rhabdomyosarcoma and a mouse colon tumour to flavone acetic acid, FAA, were studied. The LD50 values of FAA in WAG/Rij and BN rats were about 350 and 525 mg/kg respectively, independent of whether the animals were tumour bearing or not. In contrast, the LD50 value of tumour bearing BCBA mice was 50 percent of that of non-tumour bearing mice. Neither tumour volume regression nor growth delay were observed in the rat tumours growing in syngeneic rats or in nude mice, in contrast to the response of colon 38 tumours in mice. Light microscopy revealed massive tumour necrosis in the mouse tumour while no significant changes were observed in the rat tumours.