Relationship Estimation of Cell Mobility Proteins Level with Processes of Proteolysis and Lymphogenic Metastasis in Breast Cancer.

The biological aggressiveness of a tumor is determined by the ability of tumor cells to invade and metastasize which is a consequence of their acquisition of a number of phenotypic characteristics. Remodeling of the actin cytoskeleton occurs during cell migration which is carried out by various groups of actin binding proteins in the regulation of which proteasomes and calpains play an important role. Therefore the study of the relationship of proteins associated with cell motility with the processes of lymphogenous metastasis as well as the assessment of the regulatory role of intracellular proteases in these processes is extremely important for fundamental oncology. This study demonstrates the associations of actin-binding proteins with the activity of proteasomes and calpain, which are specific for tumors and metastases of the mammary gland. We proposed a possible scheme of the relationship of intracellular systems with the actin-binding proteins. The results obtained expand the fundamental understanding of the processes of tumor progression and can also be used in the search for proteins-targets for therapeutic action in molecular targeted cancer therapy.

Relationship of intracellular proteolysis with CAP1 and cofilin1 in non-small-cell lung cancer.

The main cause of death in non-small-cell lung cancer (NSCLC) is tumor progression, in which metastasis and invasion play an important role. The metastatic cascade is marked by a change in morphological, biological, biochemical and functional characteristics, including the acquisition of cellular mobility. The migration activity of tumor cells determines the work of actin-binding proteins that cause their functional partners CAP1 and cofilin. Of interest is the study of the regulation of working tandem CAP1/cofilin in NSCLC. The mechanism that regulates the level of proteins in cells is proteolysis, carried out by proteasomes and calpains. Therefore, the aim of this study was to estimate the expression of CAP1/CFL1 mRNA and their protein level in NSCLC tissues, and to analyze the possible mechanisms of their regulation by the proteasome and calpain systems. Samples of NSCLC and histological unchanged lung tissue were used (n = 42). The CAP1 and CFL1 mRNA expressions were determined by real-time PCR, the contents of proteins encoded by them were determined by Western blotting, and the activity of proteasomes and calpains by the fluorimetric method. There was an increase in the expression of mRNA and protein levels of CAP1 and cofilin in the tumor tissue compared with the unchanged lung tissue. The expression of mRNA and the level of CAP1 in tumor tissue increased during growth of the primary tumor. The cofilin level in the tumor tissue decreases against the background of increased expression of its mRNA. At the same time, during tumor growth, the activity of proteasomes and calpains increased. A negative regression relationships between the activity of proteasomes and the levels of CAP1 and cofilin, as well as the activity of calpains and the level of cofilin, were found. It can be assumed that proteasomes and calpains are involved in the degradation of CAP1 and cofilin. The data obtained suggest the importance of CAP1, cofilin and proteolytic systems in the tumor transformation and lymphogenous metastasis.