茶和姜黄素对二甲基苯并蒽诱发地鼠口腔癌的预防作用

Chemopreventive effect of tea and curcumin on DMBA-induced oral carcinogenesis in hamsters

以 0 5 %二甲基苯并蒽 (DMBA) ,涂于地鼠左侧颊囊共 6周 (每周 3次 )。在最后一次涂DMBA后 ,分别给地鼠饮 0 6 %的绿茶粉水 ,涂抹姜黄素 1 0 μmol于左侧颊囊 (每周 3次 )或二者联合处理 1 8周。茶与姜黄素二者联合处理显著降低了口腔肿瘤发病率和癌发病率 ,肉眼肿瘤数目和体积、鳞癌和异常增生及乳头状瘤数目也分别显著降低。绿茶和姜黄素单独处理也分别降低了肿瘤数目、肿瘤体积和鳞癌数目。此外 ,绿茶还降低了异常增生数目和姜黄素降低了鳞癌发病率。茶与姜黄素单独或联合处理均抑制了单纯增生、异常增生和乳头状瘤病损的BrdU增殖指数 ,茶单独或与姜黄素联合增加了异常增生和鳞癌病损的凋亡指数 ,姜黄素单独或与茶联合抑制了乳头状瘤和鳞癌病损的新生血管形成。结果表明 ,茶与姜黄素对DMBA诱发的地鼠口腔癌在启动后阶段均有预防作用 ,其机制与抑制细胞增殖。

DMBA solution (in mineral oil) was applied topically to the left cheek pouch of male Syrian golden hamsters 3 times per week for 6 weeks. After the last treatment of DMBA, the animals received 0.6% green tea powder as drinking fluid, or 10 μmol curcumin applied topically 3 times per week, or the combination of green tea and curcumin treatment, or no treatment for 18 weeks. The combination of tea and curcumin significantly decreased the oral visible tumor incidence and the squamous cell carcinoma (SCC) incidence. The combination of tea and curcumin also decreased the number of visible tumors and the tumor volume as well as the numbers of SCC, dysplasic lesions, and papillomas respectively. Green tea or curcumin treatment decreased the number of visible tumor, the tumor volume and the number of SCC respectively. Green tea also decreased the number of dysplasic lesions. Curcumin also significantly decreased the SCC incidence. Tea and curcumin, singly or in combination decreased bromodeoxyuridine (BrdU)-labeling index in hyperplasia, dysplasia, and papillomas. Tea alone and in combination with curcumin significantly increased the apoptotic index in dysplasia and SCC. Curcumin alone and in combination with tea inhibited the angiogenesis in papilloma and SCC. The results suggested that green tea and curcumin had inhibitory effects against oral carcinogenesis at the post-initiation stage and such inhibition may be related to the suppression of cell proliferation, induction of apoptosis, and inhibition of angiogenesis.