Redman R S, Krasnow S H, Sniffen R A
Oral Diagnosis Section, Dental Service, Department of Veterans Affairs Medical Center, Washington, D.C.
Oral Surg Oral Med Oral Pathol. 1992 Oct;74(4):473-80. doi: 10.1016/0030-4220(92)90299-6.
Toluidine blue O has been shown to have clastogenic and mutagenic effects when tested in vitro, suggesting that it may be a carcinogen. Because this might compromise its use for cancer screening, the carcinogenic potential of this dye was investigated in the hamster cheek pouch, an established in vivo carcinogenesis model. Male hamsters were divided into seven groups at age 5 weeks. The right pouches of four groups were painted three times weekly with 2% toluidine blue or the vehicle for toluidine blue, in conjunction with submaximal applications of 9,10-dimethyl-1,2-benzanthracene (DMBA) (groups II and III, 0.5% twice weekly), and groups IV and V, 0.1% three times weekly). The right pouches of two groups received DMBA only (group I, 0.5% three times weekly, the standard maximal amount, and group VI, 0.1% three times weekly). Group VII received toluidine blue (right pouches) and toluidine blue vehicle (left pouches) three times weekly. The extent of carcinomas and other abnormalities (scored histologically) did not differ among groups receiving the same amount of DMBA with and without toluidine blue or vehicle, and no abnormalities were seen in the pouches from group VII. These results demonstrate no effect of toluidine blue as a carcinogen, cocarcinogen, or promoter.
体外试验表明，甲苯胺蓝O具有致染色体断裂和诱变作用，提示其可能为致癌物。鉴于此可能会影响其在癌症筛查中的应用，因此利用已建立的体内致癌模型——仓鼠颊囊，对该染料的致癌潜力进行了研究。5周龄雄性仓鼠被分为7组。4组仓鼠的右侧颊囊每周用2%甲苯胺蓝或甲苯胺蓝溶剂涂抹3次，同时分别给予次最大剂量的9,10 - 二甲基 - 1,2 - 苯并蒽（DMBA）（第II组和第III组，每周2次，剂量为0.5%；第IV组和第V组，每周3次，剂量为0.1%）。另外2组仓鼠的右侧颊囊仅给予DMBA（第I组，每周3次，剂量为0.5%，为标准最大剂量；第VI组，每周3次，剂量为0.1%）。第VII组仓鼠的右侧颊囊每周涂抹3次甲苯胺蓝，左侧颊囊每周涂抹3次甲苯胺蓝溶剂。接受相同剂量DMBA（无论是否添加甲苯胺蓝或溶剂）的各组间，癌及其他异常情况（组织学评分）并无差异，第VII组仓鼠的颊囊中未观察到任何异常。这些结果表明，甲苯胺蓝作为致癌物、促癌剂或启动剂均无作用。
