Vol 5, No 3 (2018)

Despite the sufficient amount of data accumulated in the literature, there are still no factors, on the basis of which it would be possible to estimate the regional lymph nodes status in breast cancer with a high degree of accuracy. The review presents literature data relating to the influence of clinicopathological, molecular-biological and genetic characteristics of primary tumor on lymph node metastases. Data of 66 foreign and Russian articles are included.

The number of healthcare workers is over two million in Russia. Many of them are exposed to hazardous physical, chemical and biological occupational factors acting along with psychological strain. The results of large epidemiological studies carried out in various countries revealed greater cancer risk in physicians and nurses: cancer of the breast, skin, brain and other sites. Higher cancer risk of lung, breast, uterine, ovary, brain is considered to be associated with ionizing radiation. The female healthcare workers who handle antineoplastic drugs showed a greater risk of birth defects in offspring, spontaneous abortions and breast cancer. In Russia, the growing number of accidents among healthcare workers following transmission of infection by carcinogenic biological factors such as HBV and HIV is observed. Higher risk of reproductive impairments, hyperplasia of the breast and uterine tissues, breast cancer are revealed in nurses working the night shift. In Russia, there is lack of epidemiological studies of cancer risk among healthcare workers, the number of medical personal exposed to occupational carcinogens is unknown. That all does not show the actual situation in our country and does not allow setting priorities in cancer prevention among medical workers.

Background. Chaperone proteins nucleolin (NCL, or C23) and nucleophosmin (NPM, or B23) regulate key cell functions. The most tumors are characterized by over-expression of these proteins, especially in cell nuclei and on the сell surface, as NCL. Differential expression of NCL/NPM in tumor and normal cells is the basis of selective cytotoxicity of cationic peptides – expected ligands for these proteins. Objective. Analysis of the interactions between nucleolin and some peptides with high nonspecific toxicity for tumor cells. Materials and methods. The interaction of 4 previously characterized cationic peptides with nucleolin dimer was analyzed by pair molecular docking using Maestro 11 program. Results and conclusion. It is shown that these peptides can associate with receptor nucleolin molecules, forming energy-stable complexes. In the active centre of NCL molecule were found, at least, 7 positions of amino acids, which bind to the tested peptides at a high frequency (43–100 %). This indicates the conservative structure of dimer NCL, its stable binding to peptide ligands and the possibility of design the optimal structure of cationic peptides that induce tumor cell death due to competing binding to the target proteins.

Background. There are contradictory data on the detection of human papillomavirus (HPV) in the tumor tissue in endometrial cancer (EС). Objective: to assess HPV infection rates in EC tumor tissues and to establish the relationship between the status of HPV infection and tumor morphological characteristics. Materials and methods. 57 formalin-fixed paraffin-embedded (FFPE) tissue samples of EC patients aged 47–78 years were studied. HPV DNAs were found in 54.4 % of samples. Results and conclusion. We did not reveal an association between the HPV tumor status and age, metastasis or invasion depth. However, there was an interdependence between HPV infection and some morphological characteristics of the tumor: its histological type (adenocarcinomas with squamous cell differentiation were HPV-positive 1.8 times more frequent compared to adenocarcinomas without one; in the first case, tumor tissues were more often infected with HPV 16, and in the second case with HPV 18); tumor grade (in the total cohort and in serous-papillary adenocarcinomas, tumors with higher grades were more often HPV-infected: from 0 to 81.8 % and from 0 to 100 % respectively); disease stage (in the total cohort the percentage of HPV-positive tumors in stage II was 2.4 times and in stage III – 1.6 times higher than in stage I, and stage IA tumors were HPV-positive 2.3 times more often than IB tumors); type of tumor growth (tumors with infiltrative growth type were HPV-positive 1.7 times more often than with exophytic growth, and 2.2 times more often than with mixed growth). The achieved results do not allow us to conclude with confidence that HPV is the main tumor forming factor in EC.