Sayama K, Tanaka S, Matsuzawa A
Laboratory of Biology, Faculty of General Education, Meijigakuin University, Kanagawa, Japan.
Jikken Dobutsu. 1990 Oct;39(4):583-8. doi: 10.1538/expanim1978.39.4_583.
To elucidate the possible participation of the Mtv-2 gene in the background factors relevant to mammary tumorigenesis, DDD/1-Miv-2/Mtv-2 (DDD-Mtv-2) congenic and DDD/1 background mice were compared for endocrine and immune organs, mammary gland development, expression of mouse mammary tumor virus (MMTV)-gp 52 antigen, hyperplastic alveolar nodules (HAN) and mammary tumor incidence. The congenic strain had been established by introducing Mtv-2 from GRS/AJms (GR) into DDD/1 mice by repeated 12 backcrosses. Body, thymus, spleen, uterus, ovary, adrenal and pituitary weights, histology of the ovary and mammary gland development showed no differences ascribable to Mtv-2 between both strains of mice at 4,6 and 12 months of age. In contrast, MMTV-gp 52 antigen expression, HAN and mammary tumor occurred in DDD-Mtv-2 but not in DDD/1 mice. These results showed that the Mtv-2 gene stimulates mammary tumorigenesis by constitutional production of endogenous MMTV which transforms mammary epithelial cells but not by influencing the background factors relevant to mammary tumorigenesis. Furthermore, the expression of Mtv-2 appeared to be lower on the DDD/1 than on the GR background.
为阐明Mtv - 2基因在与乳腺肿瘤发生相关的背景因素中可能的作用，对DDD/1 - Miv - 2/Mtv - 2（DDD - Mtv - 2）近交系小鼠和DDD/1背景小鼠的内分泌和免疫器官、乳腺发育、小鼠乳腺肿瘤病毒（MMTV）- gp 52抗原表达、增生性肺泡结节（HAN）及乳腺肿瘤发生率进行了比较。该近交系是通过将来自GRS/AJms（GR）的Mtv - 2经12次反复回交导入DDD/1小鼠而建立的。在4、6和12月龄时，两品系小鼠的体重、胸腺、脾脏、子宫、卵巢、肾上腺和垂体重量，卵巢组织学及乳腺发育情况均未显示出与Mtv - 2相关的差异。相比之下，DDD - Mtv - 2小鼠出现了MMTV - gp 52抗原表达、HAN及乳腺肿瘤，而DDD/1小鼠未出现。这些结果表明，Mtv - 2基因通过内源性MMTV的组成性产生刺激乳腺肿瘤发生，内源性MMTV可转化乳腺上皮细胞，而非通过影响与乳腺肿瘤发生相关的背景因素。此外，Mtv - 2在DDD/1背景上的表达似乎低于在GR背景上的表达。
