Estrogen and progesterone receptors in canine mammary tumors.

采用右旋糖酐包被炭法测定37例不同组织学类型犬乳腺肿瘤细胞质雌激素和孕激素受体（ER， PR）。64.7%的肿瘤显示ER阳性（结合位点大于2 fmol/mg蛋白）。平均结合位点和离解常数（Kd）分别为8.8 fmol/mg蛋白和1.17 x <10^(-9)> M。71.0%的肿瘤检测到PR（大于5 fmol/ mg蛋白）。平均结合位点和Kd分别为24.3 fmol/mg和2.15 x <10^(-9)> m， 90% ER阳性标本PR阳性。组织病理学上，35.5%的肿瘤为良性，其余为恶性。75.7%为上皮细胞起源。良性肿瘤中ER阳性76.9%，PR阳性90.9%。而在恶性肿瘤中，ER和PR阳性率分别为58.3%和60.9%。这些结果与在人类和狗身上报告的受体数据非常相似。提示人类的内分泌治疗对犬乳腺肿瘤也可能更有效。在接下来的实验中，我们研究了肿瘤和非肿瘤乳腺组织中受体的相关性。此外，对14只正常发情周期的健康母狗的正常乳腺组织进行了检查，以确定受体的存在作为对照。组织病理学检查显示15例乳腺肿瘤中4例为增生性，其余为正常。肿瘤组织与周围组织内质网含量无显著差异。相反，乳腺肿瘤周围组织中PR含量明显低于乳腺肿瘤组织。但周围组织ER和PR含量与正常母狗乳腺组织相近。从这些结果来看，肿瘤和非肿瘤乳腺组织中ER和PR的最显著差异是PR的含量。据报道，长期服用黄体酮可诱发乳腺肿瘤。提示黄体酮和雌激素可能在犬乳腺肿瘤变的病因学中起重要作用。少

Thirty-seven canine mammary tumors with various histologic types were determined their cytosol estrogen and progesterone receptors(ER, PR) by the dextran-coated charcoal method. Out of the tumors, 64.7% showed ER positive(binding sites were more than 2 fmol/mg protein). The mean binding sites and dissociation constant(Kd) were 8.8 fmol/mg protein and 1.17 x <10^(-9)> M respectively. PR was detected in 71.0% of tumors examined(more than 5 fmol/ mg protein). The mean binding sites and Kd were 24.3 fmol/mg protein and 2.15 x <10^(-9)> M. And 90% of ER positive specimens were PR positive. Histopathologically, 35.5% of tumors were benign and the rest were malignant. Also 75.7% were epithelial origin. In benign tumors, 76.9% were ER positive and 90.9% were PR positive. But in malignant tumors, only 58.3% and 60.9% showed ER and PR positive, respectively. These results were quite similar to the receptor data reported in human and dogs. This suggests that the endocrine therapy in human may als … More o be effective in canine mammary tumors.In the next experiment, the correlation of receptors between neoplastic and non-neoplastic mammary tissues was investigated. Furthermore, 14 normal mammary tissues from healthy female dogs with normal estrous cycles were examined for the presence of the receptors as a control. Histopathologic examination revealed that 4 of 15 tumor bearing mammary tissues examined were hyperplastic and that the rest were normal. There were no significant differences in ER contents between the tumor tissues and their surrounding tissues. On the contrary, PR contents in surrounding tissues were considerably lower than those in mammary tumor tissues. But the levels of ER and PR contents in the surrounding tissues were similar to those of normal mammary tissues from normal female dogs.From these results, the most significant difference in ER and PR between neoplastic and non-neoplastic mammary tissues was the content of PR. A prolonged administration of progesterone was reported to induce mammary tumors. Thus, it is suggested that progesterone as well as estrogen may play an important role in the etiology of neoplastic change in canine mammary tumors. Less