Anticarcinogenic effect of refined amorphophallus konjac on MNNG-induced lung cancer in LACA mice

Abstract

Five hundreds and fifty LACA mice were used in 3 batches for studying the anticarcinogenic effect of Konjaku powder on MNNG-induced lung cancers. These mice (within each batch) were randomly allocated to four groups, namely, positive control (MNNG), Amorphophallus konjac (A.K.), complex (MNNG+A.K.), and blank control (C) group. In MNNG group, MNNG (250 µg) was injected intravenously once five days for seven times in each mouse, the total dosage of MNNG being 1.75 mk. In A.K. group, according to w/w, 8% A.K. was well mixed into 92% common diet for long-term breeding. In complex group, MNNG was given as that in MNNG group and the mice were reared as those in A.K. group. The mice in MNNG group and in C group were all reared by common diet. The results showed different degrees of anticarcinogenic and preventive effect of refined A.K. on MNNG-induced lung cancers in LACA mice. A.K. not only exerted effect on the number of induced cancer and precancer, causing a drop of the cancerous rate from 70.87% to 19.38% and the mean number of cancer and precancer in each animal, but also postponed the incubation period. The proportional distribution of the kinds of tumor denoted a decrease in malignancy (adenoma with malignant change), absence of adenocarcinoma, relative increase in benign adenoma, and prolonged survival time of animals. The results of experiments in 3 batches also exhibited good duplication.