三苯氧胺联合全反式维甲酸对大鼠乳腺癌的预防作用

目的 探讨联合应用三苯氧胺及全反式维甲酸对实验性大鼠乳腺癌发生促进期的化学预防作用。方法 利用二甲基苯蒽（DMBA）诱导大鼠乳腺 癌发生，在给药后第8周应用三苯氧胺（TAM）和全反式维甲酸（RA），在第24周观察大鼠乳肿瘤发生情况及乳腺发育情况。结果 对照组大鼠乳癌发生率为70．58％；TAM组与RA组发生率分别为22．02％和15．79％，明显低于对照组（P＜0．05）；TAM＋RA组无乳腺肿瘤发生（P＜0．01）。组织学及电镜观察发现，TAM组和RA组乳腺上皮均有不同程度增生或典型增生，联合用药组乳腺上皮发育良好。结论 联合应用三苯氧胺和维甲酸，二者在阻止乳发生过程中有显著的协同作用。

Preventive effect of tamoxifen combined with all-trans retinoic acid on breast carcinogenesis in Wistar rats

Objective To investigate the possible roles of chemical preventing promotion phase of breast carcinogenesis by tamoxifen combined all-trans retinoic acid in Wistar rats. Methods A total of 80 rats were randomly divided into 4 groups:control group (A), tamoxifen group(B), retinoic acid group (C) and tamoxifen combined with all-trans retinoic acid group (D). DMBA(7, 12-dimethylbenz (a) anthracence) was used to in- duce carcinogenesis in all female Wistar rats. At 8th week after DMBA administration, tamoxifen and all-trans retinoic were given. At 24th week, all rats were Killed to be observed the incidence of breast carcinoma and development of mammary gland. Results The incidence of breast carcinoma in group B(22.02% ) and group C(15. 79% ) were significant lower than that in control(70.58%) (P<0.05). In group D, no breast carcinoma was found (P < 0. 01 ). Histological and electron-microscopic observation showed proliferation of glandular epithelial cell or atypical hyperplasia in varying degree both in group B and C. No abnormal finding was found in the development of mammary gland epithelia in group D. Conclusion Tamoxifen combined with all-trans retinoic acid are synergistical in inhibiting the breast carcinogenesis.