Search

The content of urokinase- and tissue-type plasminogen activators and plasminogen activator inhibitor PAI-1 in the cytosol of primary and metastatic melanomas and benign skin pigment neoplasms was estimated by enzyme immunoassay. It was shown that local growth and invasion of melanomas are related to suppressed expression of tissue plasminogen activator. The content of urokinase plasminogen activator increases in patients with distant metastases and large thickness of the primary tumor.

Arachidonic acid metabolites are measured in primary osteogenic sarcomas, benign neoplasms, and tumor-like bone lesions. In typical osteogenic sarcomas, the contents of E and F2α prostaglandins are significantly higher than in benign bone tumors or tumor-like bone lesions. Neoadjuvant chemotherapy has different effects on the levels of prostaglandins E and F2α, thromboxane B2, and prostaglandin F1α in osteogenic sarcomas, its effectiveness depending on the mechanism of drug action and individual sensitivity of tumor cells to this drug. A negative correlation is established between the content of prostaglandins E in osteogenic sarcoma and the degree of therapeutic pathomorphosis of the tumor in patients treated with adriamycin during the preoperative period. A single transfusion of a suspension of nonactivated allogenic bone marrow cells markedly reduces the content of prostaglandins E in osteogenic sarcoma.

Expression of urokinase- and tissue-type plasminogen activators and their inhibitor PAI-1 in the cytosolic fraction of 20 osteosarcomas, 20 chondrosarcomas, 13 giant-cell bone tumors, 5 Ewing's sarcomas, and 7 osteochondral exostoses was studied by enzyme immunoassay. The content of urokinase-type plasminogen activator increased, while the concentration of tissue-type plasminogen activator decreased in bone tumors of various histological compositions compared to osteochondral exostoses. A positive correlation was found between PAI-1 content and the volume of osteo- and chondrosarcomas. Expression of urokinase-type plasminogen activator increased in patients with primary osteosarcomas characterized by early generalization of the pathological process.

The content of calmodulin in chondrosarcomas was notably lower in patients with early relapses or generalized tumor process in comparison with patients without postoperation relapses. The mean level of calmodulin in chondrosarcomas virtually did not depend on patient's sex and age and tumor location in bones. There was a tendency to an inverse correlation between calmodulin level in chondrosarcoma and the degree of tumor differentiation. The highest level of calmodulin was detected in the cytosolic fraction of chondrosarcomas containing no estrogen and androgen receptors.

Blood concentration of soluble Fas antigen is higher in patients with benign and malignant tumors in comparison with healthy subjects, which probably suggests its involvement into tumorigenesis.

The content of calmodulin in homogenates prepared from various morphological variants of primary osteogenic sarcoma varies fromn 408 to 14,255 ng/mg total protein and is lowered by neoadjunctive chemotherapy. The 5-year incidence of metastases is lower when the calmodulin content in the tumor is>6000 ng/mg protein. At calmodulin content