一种新的快速简便的抗肿瘤药物筛选模型

本研究利用DNA修复缺陷的大肠埃希氏菌343/591和正常的大肠埃希氏菌343/636的差异性DNA修复特性，建立了液体悬浮法和琼脂固体筛选方法，用于抗肿瘤药物的筛选。这两种方法简单易行，其中琼脂固体筛选方法与抗生素生物鉴定杯碟法一样简单，适合于大量筛选各种来源的抗肿瘤药物。

A novel and simple model for screening of antitumor agents

E. coli K 12 var.343/591 is a defective DNA repair strain but 343/636 is a normal type of E. coli K 12 strain. According to the different vitality between two strains in the presence of induced substances, a method for the test of the genetic toxicity was established. Generally, the substances those can make DNA damage also have antitumor activity. So the different DNA repair test (DDRT) could be applied to the screening of antitumor substances. Some fermentation broths from Actinomycetes positive by DDRT were found to have an inhibitory effect on the growth of tumor cell P385 and L1210; therefore the DDRT was tested in the screening of antitumor antibiotics from Actinomycetes . By the way, it was found that this method can test many samples from broths at a working day. Six positive strains were identified from 1200 Actinomycetes isolated from soil samples. Both liquid suspension and agar solid methods for DDRT were established for screening of antitumor antibiotics from Actinomycetes and other microbial metabolites. The solid method on an agar plate is especially more suitable because its preparative procedure is much more simple than the liquid one. The DDRT could also be used to monitor the antitumor activity of extracts from fermentation broths and the active fractions could be monitored in any steps of extraction.