Secretion of a thiol proteinase from mouse mammary carcinomas and its characterization.
Secretion of a thiol proteinase from mouse mammary carcinomas and its characterization.
复制标题
小鼠乳腺癌硫醇蛋白酶的分泌及其表征。
作者：
A. Recklies;J. Mort;Poole Ar
研究了来自C3 H/HeJ小鼠的自发性乳腺肿瘤和从乳腺肿瘤建立的移植物在器官培养外植体中分泌巯基依赖性蛋白酶活性的能力。在自发性肿瘤的培养基中检测到比移植的自发性肿瘤更多的活性。巯基蛋白酶在培养基中的积累受到放线菌酮，氢化可的松，和醛固酮的抑制，但不是由雌二醇或肽激素胰岛素或催乳素。巯基蛋白酶在酶学性质上与溶酶体组织蛋白酶B相似，但其物理性质不同。它对碱性pH稳定，在凝胶过滤时具有较大的分子尺寸（相对M.W. 39，000），并在分析等电聚焦上显示与肝组织蛋白酶B不同的同工酶谱。这种巯基蛋白酶的特征与从恶性人类乳腺肿瘤分泌的酶非常相似。
Spontaneous mammary tumors from C3H/HeJ mice and transplants established from mammary tumors were investigated for their capacity to secrete thiol-dependent proteinase activity in organ culture explants. More activity was detected in culture media from spontaneous tumors than from transplanted spontaneous tumors. The accumulation of thiol proteinase in the culture medium was inhibited by cycloheximide, hydrocortisone, and aldosterone, but not by estradiol or the peptide hormones insulin or prolactin. The thiol proteinase is similar in enzymic properties to lysosomal cathepsin B, but its physical properties are different. It is stable to alkaline pH, has a larger molecular size on gel filtration (relative M.W. 39,000) and shows a different isoenzyme pattern to liver cathepsin B on analytical isoelectric focusing. The characteristics of this thiol proteinase are very similar to an enzyme secreted from malignant human breast tumors.