Analysis of NM23 Protein and Components of Plasminogen Activation System in Tumors of Patients with Stomach Cancer with Consideration for Disease Clinical Picture and Morphology

Immunohistochemical analysis of the expression and distribution of nm23 protein and biochemical analysis of the main components of plasminogen activation system in tumors were carried out in stomach cancer patients. The data indicate that the expression of nm23 protein in malignant epithelial gastric tumors is heterogeneous, characterized by cytoplasmic and nuclear immunoreactivity. Reduced expression of the marker is more typical of poorly or undifferentiated tumors. The expression of nm23 protein positively correlated with tPA level (r s = 0.4; p = 0.01) and did not correlate with the content of uPA and PAI-1 in tumors. High PAI-1 values in tumors (>0.5 ng/mg protein) significantly correlated with lower 3-year overall survival of stomach cancer patients. These data confirm the role of the studied proteins in invasion and metastases of malignant tumors and suggest a relationship between changes in the expression of nm23 protein and mechanisms of stomach cancer progress.