We studied the effects of cathepsins produced by immunocompetent cells of intact mice, mice with B16 melanoma, mice with removed B16 melanoma, and mice with removed Ehrlich carcinoma on the growth of B16 melanoma. Incubation of B16 melanoma cells with cathepsins from immunocompetent cells of intact mice, mice with B16 melanoma, and mice with removed Ehrlich carcinoma did not affect tumor growth. Incubation of B16 melanoma cells with cathepsin from immunocompetent cells of mice with removed B16 melanoma was followed by complete loss of malignancy by these cells. Melanoma cells formed no tumor node within at least 1 year after transplantation, though exhibited high proliferative activity and formed pigmented nevi. The formation of a nevus by B16 melanoma cells is described for the first time. The existence of a mechanism regulating proliferation of malignant cells in the tumor-bearing host was hypothesized. Studies of this mechanism are expected to promote the development of new methods for the treatment of tumors.

中文翻译：

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Cathepsine L1对恶性黑色素瘤B16细胞向黑色素细胞转化的影响

我们研究了完整小鼠、患有 B16 黑色素瘤的小鼠、去除了 B16 黑色素瘤的小鼠和去除了 Ehrlich 癌的小鼠的免疫活性细胞产生的组织蛋白酶对 B16 黑色素瘤生长的影响。B16 黑色素瘤细胞与来自完整小鼠、患有 B16 黑色素瘤的小鼠和去除艾氏癌的小鼠的免疫活性细胞的组织蛋白酶一起孵育不影响肿瘤生长。将 B16 黑色素瘤细胞与来自去除了 B16 黑色素瘤的小鼠的免疫活性细胞的组织蛋白酶一起孵育后，这些细胞完全丧失了恶性肿瘤。黑色素瘤细胞在移植后至少 1 年内没有形成肿瘤节点，但表现出高增殖活性并形成色素痣。首次描述了 B16 黑色素瘤细胞形成痣。假设存在调节荷瘤宿主中恶性细胞增殖的机制。对这一机制的研究有望促进治疗肿瘤的新方法的发展。