人类乳腺癌中一种具有酸性磷酸酶活性的高分子量复合物。

A high-molecular weight complex with acid phosphatase activity in human breast cancer.

作者信息

Podhajcer O L, Filmus J E, Guman N, Mordoh J

出版信息

Mol Cell Biochem. 1984 Sep;64(2):145-53. doi: 10.1007/BF00224771.

Abstract

The presence of a high-molecular weight complex with acid phosphatase activity in the cytosol of human mammary tumors is reported. This complex appeared in the cytosol after tissue homogenization in the presence of dithiotreitol, with or without Triton X-100 and at acidic or neutral pH. Upon gel electrophoresis, this fraction showed only one band of enzyme activity which did not enter the fine pore gel. Lubrol or n-butanol had no apparent effect on this complex, and 8 M urea or 2% sodium dodecyl sulfate did not disaggregate this large molecule. After purification by gel filtration, ammonium sulfate precipitation and ion-exchange chromatography an apparent molecular weight or 10(6) was measured. It hydrolyzed typical acid phosphatase substrates such as p-NPP and alpha-NP, but also ATP and PPi. Only 44% inhibition was observed with L-(+)tartrate and it was still 40% active after 1 hr incubation at 60 degrees C. Reduction in the presence of SDS yielded several polypeptide bands. It was also detected in some samples of normal mammary tissues, but not in normal human placenta or liver.

摘要

据报道，在人乳腺肿瘤细胞溶质中存在一种具有酸性磷酸酶活性的高分子量复合物。在二硫苏糖醇存在的情况下，无论有无Triton X - 100，在酸性或中性pH条件下进行组织匀浆后，这种复合物出现在细胞溶质中。经凝胶电泳后，该组分仅显示一条酶活性带，且该带不进入小孔径凝胶。月桂醇或正丁醇对该复合物无明显影响，8M尿素或2%十二烷基硫酸钠也不能使该大分子解聚。经凝胶过滤、硫酸铵沉淀和离子交换色谱法纯化后，测得其表观分子量为10(6)。它能水解典型的酸性磷酸酶底物，如对硝基苯磷酸酯（p - NPP）和α - 萘基磷酸酯（α - NP），也能水解ATP和焦磷酸（PPi）。L-(+)酒石酸仅产生44%的抑制作用，在60℃孵育1小时后仍有40%的活性。在十二烷基硫酸钠（SDS）存在下还原产生几条多肽带。在一些正常乳腺组织样本中也检测到了它，但在正常人体胎盘或肝脏中未检测到。