Relation between Tetraspanin- Associated and Tetraspanin- Non- Associated Exosomal Proteases and Metabolic Syndrome in Colorectal Cancer Patients

Purpose: Exosomal proteases are important in regulation of molecular signaling from growth factor receptors and adhesion molecules and also the regulation of cell motility and protein folding. The aim of this study was to evaluate the level of ADAM10, ADAM17 and 20S proteasomes in exosomes isolated from colorectal cancer patients (CRCPs) in relation with clinical and histopathological parameters. Methods: Blood plasma exosomes of 60 CRCPs at stage T2-4N0-2M0-1 and 10 control subjects (CSs) with colorectal polyps were isolated using ultrafiltration in combination with ultracentrifugation. The level of tetraspanin-associated (ADAM20 and ADAM17) and tetraspanin-non-associated (20S proteasome) proteases were evaluated by flow cytometry and western blot analysis. Results: The ADAM10-/ ADAM17- population predominated in plasma exosomes of CRCPs and the level of ADAM10+ exosomes was significantly higher in exosomes of CSs compared with CRCPs. No difference was found between subpopulations of ADAM10/ADAM17 exosomes and level of exosomal 20S proteasomes in terms of sex, age and tumor grade. Simultaneous decrease of ADAM10+/ADAM17-subpopulation of exosomes and level of exosomal 20S proteasomes in patients with metastatic CRC was observed compared with patients with non-metastatic CRC. The level of ADAM17+ exosomes significantly reduced in exosomes of CRCPs with metabolic syndrome compared to CRCPs without metabolic syndrome( 3.97±0.71 (%) vs. 13.04±1.34 (%), respectively (p<0.05). A decrease in the 20S proteasomes level in plasma exosomes was revealed in CRCPs with metabolic syndrome compared with CRCPs without metabolic disorders ( 1.90±0.25 (r.u.) vs. 2.92±0.42 (r.u.) respectively( (p<0.05). Conclusion: According to findings of this study, it seems that exosomal proteases can be promising molecular predictors of hematogenous metastasis in patients with non-metastatic CRC. Further studies on subpopulation composition of exosomes CRCPs are need for elucidating the role of tetraspanin-associated and tetraspanin-non-associated exosomal proteases in CRC development and progression.

Functional activity of natural killer cells in biological fluids in patients with colorectal and ovarian cancers.

AIM OF THE STUDY: To compare the functional activity of natural killer cells depending on the presence of a malignant process and its dissemination. MATERIAL AND METHODS: The study included 20 patients with Stage IIIB, C (FIGO, 2009) ovarian cancer, 10 patients with benign ovarian tumours (BOT), and 20 patients with colorectal cancer (T2-4N0-2M0). The control group consisted of 9 healthy donors. To evaluate the number and functional activity of NK cells, multicolour flow cytometry was performed. RESULTS: In cancer patients, the relative number of activated NK cells secreting granzyme B (GB) (CD56+CD107a+GB+PF-) was significantly decreased, and the proportion of degranulated NK cells (CD56+CD107a+GB-PF-) was significantly increased, compared to those observed in healthy donors. The total number of NK cells in peripheral blood was low in ovarian cancer patients (p < 0.05). The proportion of activated peripheral blood NK cells containing cytolytic granules GB and perforin (PF) in colorectal cancer patients increased with tumour growth. However, lymph node metastasis did not affect the content and activation of NK cells. Comparative analysis of NK-cell populations in patients with benign and malignant ovarian tumours revealed that the level of CD56+ cells was significantly higher in ascites than in peripheral blood. However, CD56+CD107a+ activated cells and CD56+CD107a+GB+PF+ cells were found more frequently in ascites of BOT patients than in ovarian cancer patients. The degranulated population of NK cells (CD56+CD107a+GB-PF-) was mainly observed in the peripheral blood of ovarian cancer patients.

Molecular targets for the therapy of cancer associated with metabolic syndrome (transcription and growth factors).

Metabolic syndrome (MS) is one of the leading risk factors for the development of cardiovascular diseases, type II diabetes mellitus and reproductive system diseases. Currently, not only cardiovascular disease and reproductive history risks related with MS are frequently discussed, but it has been also shown that MS is associated with increased risk of some common cancers (endometrial cancer, postmenopausal breast cancer, colorectal cancer, biliary tract cancers and liver cancer for men). Further studies are required to understand the mechanisms of the involvement of MS components in the pathogenesis of malignant neoplasms. Changes in the expression of transcription and growth factors in the peripheral tissues as well as in cancer tissues of patients with MS were revealed. Transcription factors (AMP-activated protein kinase-1, STAT3, sterol regulatory element-binding protein-1 and peroxisome proliferator-activated receptor-γ), leptin and adiponectin receptors seem to be the most promising molecular targets for the therapy of cancers associated with MS.