[Effects of anticancerous agents on the microvascular system of experimental malignant tumors (author's transl)].
Walker 256 carcinosarcomas were transplanted under the skin and in the bone marrow of the femur of Wistar rats to investigate the tumor angiogenesis and effect of anticancerous agents on it. Microangiography was performed on tumors in different stages after transplantation and on treated tumors in different stages after a single shot of Adriacin or Endoxan into the intraperitoneum. The tumors were histologically examined. The results were as follows: 1. Angiogenesis was found at the host side near the tumor in the beginning of the subcutaneous transplantation and formation of vascaular network was seen at the peripheral area in the tumor after 5-7 days. No blood vessel was found at the central region of the tumor, and so-called "sinusoidal lake" was seen at the border zone of central and peripheral regions, suggesting the impending central necrosis. The vascular network became loose and blood vessels became of larger diameters and sinusoidal blood vessels were found afater about 14 days. In the case of intramedullary transplantation, blood flow stopped in the marrow already after about 10 days and rich network of blood vessels was observed in the spicula. 2. In the Adriacin group, only a weak inhibitory effect on tumor growh was found. There was no degeneration of tumor cells, but a little disorder of tumor cell cords. The effects of the drug on the capillaries were remarkable. The diameter of the capillary was narrowed, with fragmented vascularity and disappearance of capillary network. It was estimated that effective amount of the drug might not reach tumor cells because of circulatory disturbance due to obstruction of the capillaries caused by Adriacin. 3. In the Endoxan group, inhibitory effect of the drug was remarkable, and degeneration and transformation into giant cells of tumor cells, with a decrease of tumor cells and proliferation of interstitial connective tissues. The microvascular system maintained its network structure for rather a long period and the network was reduced with an increase of the connective tissue, but no fragmentation was found. It was suggested that sufficient Endoxan might have reached the tumor cells and cause their degeneration and destruction, followed by decrease of tumor angiogenesis factor (TAF) and by secondary reduction and disappearance of the microvascular system.
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D002279:Carcinoma 256, Walker / Q000098:blood supply* / Q000188:drug therapy / Q000473:pathology; D003520:Cyclophosphamide / Q000494:pharmacology / Q000627:therapeutic use; D004317:Doxorubicin / Q000494:pharmacology / Q000627:therapeutic use; D008297:Male; D008833:Microcirculation / Q000187:drug effects*; D051381:Rats
D000970:Antineoplastic Agents; D004317:Doxorubicin; D003520:Cyclophosphamide