Background: Collagenases are enzymes starting collagen degradation. The role of collagenases in renal carcinoma development is not well understood. Objective: Evaluation of collagen content and collagenase expression and activity in human kidney cancers. Methods: Collagen content was measured by the hydroxyproline assay. The expression and the content of collagenases were evaluated by Western blotting and ELISA. Fluorogenic substrate was used to measure enzyme activity. Results: Collagen content significantly decreases with the progression of kidney cancer. Both collagenases are first present in high molecular complexes in both control and cancer tissue. The healthy part of the kidney contains similar amounts of both collagenases. Collagenase content decreased significantly in tumor tissue with increasing cancer stage. MMP-13 activity is much higher than that of MMP-1 in all tissues investigated. We observed increasing collagenase activity (MMP-1 and MMP-13) with increasing renal cancer grade. Conclusions: The lower content and higher activity of the collagenases investigated in cancer tissue indicate that most of these enzymes are in active form in renal carcinoma. The lower collagen content in cancer tissue can be explained at least in part by increased collagenase activity.

中文翻译：

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人肾癌中胶原酶 MMP-1 和 MMP-13 的表达受抑制但活性不受抑制

背景：胶原酶是启动胶原降解的酶。胶原酶在肾癌发展中的作用尚不清楚。目的：评估人肾癌中的胶原含量和胶原酶表达和活性。方法：胶原含量通过羟脯氨酸测定法测定。通过蛋白质印迹和ELISA评估胶原酶的表达和含量。荧光底物用于测量酶活性。结果：胶原含量随着肾癌的进展而显着降低。两种胶原酶首先存在于对照和癌组织中的高分子复合物中。肾脏的健康部分含有相似量的两种胶原酶。随着癌症分期的增加，肿瘤组织中胶原酶的含量显着降低。在所有研究的组织中，MMP-13 的活性远高于 MMP-1。我们观察到胶原酶活性（MMP-1 和 MMP-13）随着肾癌分级的增加而增加。结论：在癌组织中研究的胶原酶的含量较低且活性较高，表明这些酶中的大多数在肾癌中处于活性形式。癌组织中较低的胶原含量至少可以部分地由增加的胶原酶活性来解释。