The Composition of Small Extracellular Vesicles (sEVs) in the Blood Plasma of Colorectal Cancer Patients Reflects the Presence of Metabolic Syndrome and Correlates with Angiogenesis and the Effectiveness of Thermoradiation Therapy.

The majority of colorectal cancer patients (CRCPs) develop tumors on the background of "metabolically healthy obesity" or metabolic syndrome. The aim of the work was to study the levels of matrix metalloproteinases (MMPs) and heat shock proteins (HSPs) on the surface of blood plasma CD9-positive and FABP4-positive small extracellular vesicles (sEVs) from CRCPs depending on metabolic status and tumor angiogenesis, as well as to evaluate the sEVs markers as predictors of the effectiveness of thermoradiotherapy. In CRCPs, compared with patients with colorectal polyps (CPPs), the proportion of triple positive EVs and EVs with the MMP9+MMP2-TIMP1+ phenotype increased significantly among FABP4-positive EVs (adipocyte-derived EVs), which in general may indicate the overexpression of MMP9 and TIMP1 by adipocytes or adipose tissue macrophages in CRCPs. The results obtained have prospects for use as markers to clarify cancer risk in CPPs. One can assume that for CRCPs with metabolic syndrome or metabolically healthy obesity, it is the FABP4+MMP9+MMP2-TIMP1- population of circulating sEVs that is the most optimal biomarker reflecting tumor angiogenesis. Determining this population in the blood will be useful in monitoring patients after treatment for the early detection of tumor progression. CD9+MMP9+MMP2-TIMP1- and MMP9+MMP2-TIMP1+ subpopulations of circulating sEVs are the most promising predictors of the efficacy of thermoradiation therapy because their levels at baseline differ significantly in CRCPs with different tumor responses.

Five-year survival in luminal breast cancer patients: relation with intratumoral activity of proteasomes.

Background: The purpose of the study was to analyze the relationship between the caspase-like (CL) and chymotrypsin-like (ChTL) activities of proteasomes and the 5-year overall and metastasis-free survival rates in patients with luminal breast cancer. Methods: The study included 117 patients with primary operable invasive breast cancer (T1-2N0-1M0). Tissue samples from breast cancer patients were obtained as a result of the radical mastectomy or breast conserving surgery, which was a first line of therapy. The ChTL and CL proteasomes activities in the tumor tissue and in the surrounding adjacent breast tissues were assessed using the fluorometric method. The coefficients of ChTL (cChTL) and CL (cCL) proteasomes activities were also determined. The coefficients were calculated as the ratio of the corresponding proteasomes activity in the tumor tissue to the surrounding adjacent breast tissues. Within 5 years of follow-up, hematogenous metastases occurred in 14% of patients with luminal A breast cancer, in 31% of patients with luminal B human epidermal growth factor receptor-2 (HER-2) negative and in 23% of patients with luminal B HER-2 positive breast cancers. The study protocol was approved by the Local Ethics Committee of the Cancer Research Institute of Tomsk National Research Medical Center. Written informed consent was obtained from all patients. Results: An increase in the ChTL and CL proteasomes activities was shown in all studied molecular subtypes of breast cancer compared to adjacent tissues. It was found that the cChTL of >35.9 U/mg protein and the cCL of >2.21 in breast cancer patients were associated with the development of distant metastases. In patients with luminal A breast cancer, the 5-year metastasis-free survival rates were associated only with the value of cCL of proteasomes (log-rank test: P=0.008). In patients with luminal B HER-2 negative breast cancer, the 5-year metastasis-free survival rates were associated with the levels of ChTL and cCL proteasomes activities (log-rank test: P=0.02 and P=0.04, respectively). Conclusions: The data obtained on the correlation of 5-year metastasis-free survival rates with the level of proteasomes activities indicate the possibility of their use as additional prognostic criteria for breast cancer.

The Association of the BRAF-V600E Mutation with the Expression of the Molecular Markers in the Primary Tumor and Metastatic Tissue in Papillary Thyroid Cancer.

OBJECTIVE: The aim of this study was investigation the AKT / mTOR signaling pathway components, transcriptional and growth factors, as well as steroid hormone receptors and nuclear factors Brn-3α and TRIM16 expression in the tissue of the primary thyroid tumor and metastases, depending on the BRAF- V600E status. MATERIAL AND METHODS: The study was enrolled 20 patients with PTCs, who underwent surgical treatment. They were divided into negative BRAF-V600E status (12 people), positive BRAF-V600E status (8 patients). Mutation status was assessed in paired metastatic tissue samples. The molecular marker expression was determined by real-time PCR. The Real-time-PCR-BRAF-V600E reagent kit evaluated the BRAF-V600E mutation. RESULTS: A decrease in the PDK kinase, PTEN, VHL mRNA level in primary cancers was noted, compared with metastases' tissue. An increase in AKT, GSK-3ß, mTOR, 70s 6 kinase was revealed in cancers with point mutation compared with the primary tumor without a mutation. Positive mutation status was accompanied by an increase in NF-κB p65, NF-κBp50, VEGF HIF-2 VHL level compared to the primary tumor with negative BRAF-V600E status. In the metastases with the BRAF-V600E point mutation, a decrease in the PDK kinase, HIF-1; VHL; TRIM16, and ERα expression was observed, compared to lymph node metastases (LNMs) without the mutation. The concordance in the BRAF-V600E tumor status and LNMs was observed only in 50% of patients. If the BRAF gene status did not match PTCs and LNMs, an increase in the mTOR, NFkBp65, VHL, and ERα mRNA levels was found in the PTCs. In LNMs, there was an increase in the c-RAF PTEN NFkBp65 VHL expression compared to non-concordant ones. CONCLUSION: The heterogeneity in the primary tissue's expression profile and metastases was noted. The BRAF-V600E mutation can affect the molecular characteristics both in the primary cancers and metastases. The discrepancy between the mutant status and the molecular factors expression variability in the primary tumor and LNMs determines its progression.

Exosomal Protease Cargo as Prognostic Biomarker in Colorectal Cancer.

OBJECTIVE: The aim of the study was to develop a model for predicting cancer risk in colorectal polyps' patients (CPPs), as well as to reveal additional prognosis factors for Stage III colorectal cancer based on differences in subpopulations of tetraspanins, tetraspanin-associated and tetraspanin-non-associated proteases in blood plasma exosomes of CPPs and colorectal cancer patients (CRCPs). METHODS: The subpopulations of CD151- and Tspan8-positive exosomes, the subpopulations of metalloproteinase at the surface of СD9-positive exosomes and the level of 20S proteasomes in plasma exosomes in 15 CPPs (tubulovillous adenomas) and 60 CRCPs were evaluated using flow cytometry and Western blotting. Logistic regression analysis was performed to predict cancer risk of CPPs. RESULTS: The levels of 20S proteasomes in exosomes, MMP9+, MMP9+/MMP2+/EMMPRIN+ in CD9-positive blood plasma exosomes are associated with the risk of malignant transformation of colorectal tubulovillous adenomas.  In patients with Stage III CRC, the levels of 20S proteasomes (less than 2 units) and MMP9+ subpopulations (more than 61%) in plasma exosomes are unfavorable prognostic factors for overall survival. The levels of 20S proteasomes and ADAM10+/ADAM17- subpopulations in CD9-positive blood plasma exosomes are the most significant values for predicting relapse-free survival. CONCLUSION: Protease cargo in CD9-positive blood plasma exosomes is prognostic biomarker for colorectal polyps and colorectal cancer.

Estrogen Receptors and Ubiquitin Proteasome System: Mutual Regulation.

This review provides information on the structure of estrogen receptors (ERs), their localization and functions in mammalian cells. Additionally, the structure of proteasomes and mechanisms of protein ubiquitination and cleavage are described. According to the modern concept, the ubiquitin proteasome system (UPS) is involved in the regulation of the activity of ERs in several ways. First, UPS performs the ubiquitination of ERs with a change in their functional activity. Second, UPS degrades ERs and their transcriptional regulators. Third, UPS affects the expression of ER genes. In addition, the opportunity of the regulation of proteasome functioning by ERs-in particular, the expression of immune proteasomes-is discussed. Understanding the complex mechanisms underlying the regulation of ERs and proteasomes has great prospects for the development of new therapeutic agents that can make a significant contribution to the treatment of diseases associated with the impaired function of these biomolecules.

Progesterone Receptor Expression in the Benign Prostatic Hyperplasia and Prostate Cancer Tissues, Relation with Transcription, Growth Factors, Hormone Reception and Components of the AKT/mTOR Signaling Pathway.

BACKGROUND: Progesterone receptor (PR) is a critical regulator in reproductive tissues that controls a variety of cellular processes. The objective of the study was to study the PR expression in patients with benign prostatic hyperplasia and prostate cancers in connection with the transcription, growth factors, AR, ERα, ERß, and components of the AKT/mTOR signaling pathway expression. MATERIALS AND METHODS: Ninety-seven patients with prostate pathology were enrolled in the study. Forty-two patients had benign prostatic hyperplasia (BH). Fifty-five patients had locally advanced prostate cancer (PCa). The PSA level and the amount of testosterone in the serum were measured using an ELISA assay. The expression level of NF-κB p65, NF-κB p50, HIF-1, HIF-2, growth factor VEGF, VEGFR2, CAIX, as well as AR, ERα, ERß, PR, Brn-3α, TRIM16 were quantified by RT-PCR. The protein level of Brn-3α, TRIM16 was detected by Western Blotting. RESULTS: Growth in PR expression was observed in PCa tissues compared to BH ones without changes in the clinical and pathological features of the patients. An increase in PR expression was detected in patients with PCa compared to BH. Its mRNA level depended on the expression of AR, Brn-3α, and TRIM16, components of the AKT/mTOR signaling pathway, transcription, and growth factors. An increase in the TRIM16 expression in the PCa tissues was noted in the case of a low PR level. We revealed the growth in PR expression was accompanied by the suppression of the signaling cascade activity, AR, Brn-3α mRNA level, and the enhanced PTEN expression in PCa tissues. The increase in PR expression in PCa led to a decrease in the level of mRNA of NF-κB, HIF-1, VEGF, and VEGFR2. CONCLUSION: In general, the data indicated the significance of the PR expression in the development of the prostate pathology that affected the cross-talk between the steroid hormone reception and signal transduction. 
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Transcription factors Brn-3α and TRIM16 in cancers, association with hormone reception.

Sex hormones, regulating normal physiological processes of most tissues and organs, are considered to be one of the key factors in the development of hormone-dependent cancer and formation of the hormone-resistant tumor phenotype. Recently, the importance of the system for control of hormone receptors expression mediated by nuclear peptides became evident. This system is involved in the regulation of normal physiological processes, in the pathogenesis of many diseases as well as oncogenesis. In the review, we discuss the relationships of the two regulatory peptides - Brn-3α, TRIM16 with hormone receptors. The transcription factor Brn-3α is able to affect the transcription activity of androgen and estrogen receptors. It is observed the participation of TRIM16 protein in the pathogenesis of hormone-dependent tumors due to its "anti-estrogenic effect". Additionally, they are involved in the key intracellular processes, such as proliferation, cell differentiation, and programmed death - apoptosis. Thus, Brn-3α and TRIM16 are associated with cancer development and progression. By understanding these alterations, we can identify potential markers and novel biochemical therapeutic targets. It makes clear the association between classical hormone-dependent tumors and less sensitive ones with the modification in the level of hormone receptors.

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.

Metalloproteinases at the surface of small extrcellular vesicles in advanced ovarian cancer: Relationships with ascites volume and peritoneal canceromatosis index.

Metalloproteinases and their extracellular matrix metalloproteinase inducer (EMMPRIN) play an essential role in the regulation of signaling from growth factors receptors and adhesion molecules, cell motility and extracellular matrix degradation. The aim of the study was to evaluate the relationship between the levels of small extracellular vesicles (sEVs) metalloproteinases, such as ADAM10, ADAM17, MMP2, MMP9 and EMMPRIN and ascites volume and peritoneal canceromatosis index in advanced ovarian cancer patients (OCPs). The subpopulations of metalloproteinases at the surface of sEVs of borderline ovarian tumor patients (BOTPs) (n = 20, 36.5 ±â€¯2.5 years) and previously untreated advanced OCPs (n = 35, 56.5 ±â€¯2.5 years) were evaluated using flow cytometry. The metalloproteinase subpopulations of CD9-positive sEVs isolated from plasma of BOTPs and OCPs appeared to be quite similar. However, a significant difference in the expression of ADAM-metalloproteinases in ascites sEVs was found between BOTPs and OCPs. The level of sEVs metalloproteinases in OCPs significantly depended on the ascites volume. A statistically significant relationship between the level of ADAM10+/ADAM17- subpopulation in plasma sEVs and the peritoneal canceromatosis index was found (R = 0.66, p < .05). The levels of metalloproteinases and EMMPRIN in circulating sEVs, as well as the assessment of individual subpopulations may be promising approaches to OCPs managing.

Protease Cargo in Circulating Exosomes of Breast Cancer and Ovarian Cancer Patients

Background: As is known, exosomes play an important role in promoting progression of cancers by increasing its invasive potential. The aim of this study was to evaluate the levels of tetraspanine-associated (ADAM-10) and tetraspanine-nonassociated proteases (20S proteasomes) in exosomes from culture medium, plasma exosomes of patients with breast tumors and plasma and ascites of ovarian tumor patients. Methods: MCF-7 and SVO-3 culture mediums and blood samples from healthy females (n = 30, HFs), patients with diffuse dyshormonal dysplasia of the breast (n=28, BBTPs), breast cancer patients (n=32, BCPs), borderline ovarian tumor patients (n=20, BOTPs) and blood and ascites samples ovarian cancer patients (n=35, OCPs) were included in the study. Exosomes from plasma, ascites and culture mediums were isolated and characterized in according to Extracellular Vesicles Society. The expression levels of 20S proteasome and ADAM-10 in exosomes were determined using flow cytometry and western blot analysis, correspondingly. Results: The subpopulation composition of the exosomes from MCF-7 culture medium and from blood plasma of HFs and breast diseases patients is similar, however CD9/CD24 subpopulation significantly increased at cell supernatant. The similar results was obtained for exosomes from SVO-3 medium and blood plasma and ascites of ovary tumor patients, but CD9/CD24 subpopulation significantly decreased at cells and illness samples, however CD63/CD24 exosomes increased significantly from cell supernatant. 20S proteasome level is significantly increased in exosomes from MCF-7 and SVO-3 culture medium, breast tumor patients and OCPs plasma in comparison to HUVEC culture medium and HFs plasma samples. At CD9-positive exosomes from BCPs plasma and MCF-7 was reveal a high expression of ADAM-10 and low expression is from BBDPs plasma and ovarian tumor patients plasma/ ascites samples. Exosomes from ascites OCP had high expression of ADAM-10 in the CD24-positive subpopulation. Conclusion: Breast and ovarian cancer development is connected with functioning of immune proteasome forms in plasma and ascites exosomes, while increased ADAM10 expression at CD9-positive exosome was associated with breast cancer and at CD24-positive subpopulation ­ with ovarian cancer. Obtained data confirm role of exosomal proteases in tumor progression.

The role of metabolic syndrome variant in the malignant tumors progression.

Metabolic syndrome (MS) is one of the leading risk factors for the development of some common cancers (endometrial cancer, postmenopausal breast cancer, colorectal cancer). Currently, a drug-induced metabolic syndrome related with androgen deprivation therapy in patients with prostate cancer represents a serious medical problem. Not only MS, or its individual components, but MS variants with different levels of leptin, adiponectin, visfatin, resistin are associated with tumor invasion, metastasis and survival rates in patients with MS-associated malignancies.

[Targeting of the AKT/m-TOR Pathway: Biomarkers of Resistance to Cancer Therapy--
AKT/m-TOR Pathway and Resistance to Cancer Therapy].

Resistance to cancer therapy continues to be a major limitation for the successful treatment of cancer. There are many published studies on therapy resistance in breast and prostate cancers; however, there are currently no data on molecular markers associated with resistance. The conflicting data were reported regarding the AKT/m-TOR signaling pathway components as markers predicting resistance. The AKT/m-TOR signaling pathway is involved in the development of many human cancers; its activation is related to cell proliferation, angiogenesis, apoptosis, as well as to therapy resistance. Molecular alterations in the AKT/m-TOR signaling pathway provide a platform to identify universal markers associated with the development of resistance to cancer therapy.

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.

Effect of Targeted Therapy With Pazopanib on Expression Levels of Transcription, Growth Factors and Components of AKT/m-TOR Signaling Pathway in Patients with Renal Cell Carcinoma

Background: The effect of the targeted therapy on cancer molecular markers remains currently unknown. The aim of the study was to investigate the expression and content of transcription, growth factors and components of the AKT/m-TOR signaling pathway in kidney cancer patients before and after targeted therapy with pazopanib. Methods: A total of 157 patients with renal cell carcinoma were enrolled into the study. The level of mRNA expression was investigated by real-time PCR, and the contents of transcription and growth factors, as well as the levels of AKT/m- TOR signaling pathway components were determined by ELISA and Western blotting. Results: Targeted therapy with pazopanib resulted in a 3.1-fold decrease in HIF-2α expression that was accompanied by a reduction in the levels of NF-κB p65 and p50, HIF-1α and CAIX. The levels of GSK-3ß and AKT mRNA were increased; however, the levels of corresponding proteins remained low. The targeted therapy with pazopanib did not influence the level of PTEN phosphatase. A 1.9-fold increase in the level of p70 S6 (S371) was observed after therapy. Conclusion: The efficacy of tyrosine kinase inhibitors is associated with the changes in the angiogenic factors. Molecular characteristics of cancer could determine markers of disease progression as well as potential targets for anticancer therapies

Association of IGFBP-6 Expression with Metabolic Syndrome and Adiponectin and IGF-IR Receptor Levels in Colorectal Cancer.

PURPOSE: To assess IGFBP-6 expression in relation with the presence of the metabolic syndrome, adiponectin receptors (AdipoR1 and AdipoR2) and IGF-IR levels in colorectal adenocarcinoma cases. MATERIALS AND METHODS: IGFBP-6 mRNA and protein levels were analyzed using real-time quantitative PCR and Western blotting in 46 patients. ELISA and ow cytometry were used for evaluation of AdipoR1, AdipoR2 and IGF-IR. RESULTS: The results showed that IGFBP-6 mRNA expression and the IGFBP-6 content were higher in tumor tissue samples of colorectal cancer patients with and without the metabolic syndrome. In addition, IGFBP-6 mRNA expression was associated with tumor invasion (tumor size) and the IGFBP-6 protein level was associated with nodal status. Positive correlations and positive nonlinear relations were found between the IGFBP-6 level and the AdipoR1 and AdipoR2 contents in colorectal cancer patients. CONCLUSIONS: The IGFBP-6 mRNA level and protein level were found to be associated with presence of the metabolic syndrome. Positive correlations indicated probable cross-talk between the IGF-IR-mediated and adiponectin-mediated signaling pathways in colorectal carcinomas. IGFBP-6 may be considered as a potential biomarker associated with lymphogenous metastasis and the metabolic syndrome in colorectal cancer.

Insulin-Like Growth Factors and Their Binding Proteins in Tumors and Ascites of Ovarian Cancer Patients: Association With Response To Neoadjuvant Chemotherapy

Purpose: Tumor cell growth and sensitivity to chemotherapy depend on many factors, among which insulin-like growth factors (IGFs) may play important roles. The aim of the present study was to evaluate the levels of insulin-like growth factors (IGFs) and IGF binding proteins (IGFBPs) in primary tumors and ascites as predictors of response to neoadjuvant chemotherapy in ovarian cancer (OC) patients. Materials and Methods: Tumor tissue samples and ascitic fluid were obtained from 59 patients with advanced OC. The levels of IGF-I, IGF-II, IGFBP-3, IGFBP-4 and PAPP-A were determined using ELISA kits. Taking into account the data on expression of these IGF-related proteins and outcome, logistic regression was performed to identify predictors of response to neoajuvant chemotherapy. Results: Human ovarian tumors expressed IGFs, IGFBP-3, IGFBP-4 and PAPP-A and these proteins were also present in ascites fluid and associated with its volume. IGFs and IGFBPs in ascites and soluble PAPP-A might play a key role in ovarian cancer progression . However, levels of proteins of the IGF system in tumors were not significant predictors of objective clinical response (oCR). Univariate analysis showed that the level of IGF-I in ascites was the only independent predictor for oCR. Conclusion: The level of IGF-I in ascites was shown to be an independent predictor of objective clinical response to chemotherapy for OC patients treated with neoadjuvant chemotherapy and debulking surgery.

Proteasome functioning in breast cancer: connection with clinical-pathological factors.

Breast cancer is one of four oncology diseases that are most widespread in the world. Moreover, breast cancer is one of leading causes of cancer-related deaths in female population within economically developed regions of the world. So far, detection of new mechanisms of breast cancer development is very important for discovery of novel areas in which therapy approaches may be elaborated. The objective of the present study is to investigate involvement of proteasomes, which cleave up to 90% of cellular proteins and regulate numerous cellular processes, in mechanisms of breast cancer development. Proteasome characteristics in 106 patient breast carcinomas and adjacent tissues, as well as relationships of detected proteasome parameters with clinical-pathological factors, were investigated. Proteasome chymotrypsin-like activity was evaluated by hydrolysis of fluorogenic peptide Suc-LLVY-AMC. The expression of proteasome subunits was studied by Western-blotting and immunohistochemistry. The wide range of chymotrypsin-like activity in tumors was detected. Activity in tumors was higher if compared to adjacent tissues in 76 from 106 patients. Multiple analysis of generalized linear models discovered that in estrogen α-receptor absence, tumor growth was connected with the enhanced expression of proteasome immune subunit LMP2 and proteasome activator PA700 in tumor (at 95% confidence interval). Besides, by this analysis we detected some phenomena in adjacent tissue, which are important for tumor growth and progression of lymph node metastasis in estrogen α-receptor absence. These phenomena are related to the enhanced expression of activator PA700 and immune subunit LMP7. Thus, breast cancer development is connected with functioning of immune proteasome forms and activator PA700 in patients without estrogen α-receptors in tumor cells. These results could indicate a field for search of new therapy approaches for this category of patients, which has the worst prognosis of health recovery.

Expression of vascular endothelial growth factor and transcription factors HIF-1, NF-kB expression in squamous cell carcinoma of head and neck; association with proteasome and calpain activities.

INTRODUCTION: The transcription factors NF-kB, HIF-1 and vascular endothelial growth factors (VEGF) are known to play an important role in pathogenesis of squamous cell carcinoma of head and neck (SCCHN). PURPOSE: The aim of the study was to determine the NF-kB, HIF-1 and VEGF, expression their characteristics in squamous cell carcinoma of head and neck. METHODS: Transcription factors and VEGF expression were measured by ELISA kits. Proteasome and calpain activity were determined using specific fluorogenic substrate. Proteasome subunits composition was measured by Western blot analysis. RESULTS: In the present study, we revealed the connection between SCCHN lymphogenous metastasis development and NF-kB p50 expression. An increase in total, 26S and 20S proteasome activities and calpain activity was observed in cancer tissues in comparison with agreed standard (non-transformed tissue). The dynamics of changes in proteasome activity and proteasome subunits content during lymph nodes metastasis development had a complex pattern. Nonparametric analysis of variance showed the connection between the extent of metastatic affection of regional lymph nodes, total proteasome activity and LMP2 expression. Proteasome and calpain systems corresponded and interacted with each other. We also revealed a positive correlation between the NF-kB p65 and p50 expression and proteasome activity. CONCLUSION: Taken together, our results suggest that above mentioned transcription factors and intracellular proteolytic systems are involved in SCCHN progression and metastasis. Moreover, the opportunity of transcription factors regulation by proteasome takes place in oncogenesis of SCCHN. The results provide a basis for new prognostic tests and development of novel targeted therapy.

Association of growth factors, HIF-1 and NF-κB expression with proteasomes in endometrial cancer.

Insulin-like growth factors (IGFs), vascular endothelial growth factor (VEGF), hypoxia-inducible factor-1 (HIF-1), and nuclear factor kappa-B (NF-κB) are known to play an important role in endometrial cancer pathogenesis. However, the proteolytic regulation of these factors is still poorly understood. We studied the correlation between chymotrypsin-like activity of proteasomes and IGF-I, IGF-II, VEGF, HIF-1, and NF-κB levels in endometrial cancer tissues. It was shown that the total activity of proteasomes and the activity of the 20S and 26S proteasomes in malignant tumors were significantly higher than those observed in the normal endometrium. Negative relationships between the proteasome activity and IGF-I, HIF-1, and NF-κB p50 expressions were found. High 20S proteasome activity was associated with increase of HIF-1 level. Positive relationships between IGF-I expression and two classic forms of NF-κB p50 and p65 in endometrial cancer were revealed. The data obtained indicate the possible proteasomal regulation of growth and transcription factors. The major pool of IGF-I is located in the extracellular space, and it is likely that extracellular proteasomes also take part in the regulation of the IGF-I content. The present data show the evidence of proteasome regulation of growth and nuclear factors that can play an important role in cancer pathogenesis.

Production of nitric oxide by hypoxic radiosensitizer sanazole.

AIM: In this work we investigated the ability of hypoxia-selective radiosensitizer--sanazole to produce nitric oxide (NO). METHODS: NO formation was determined by spectophotometric method in the reaction with sanazole and oxyhemoglobin. In suspensions of lymphoma EL-4 and mastocytoma P 8815 cell NO production was estimated indirectly as nitrite concentration in the supernatant fraction. RESULTS: Transformation of oxyhemoglobin by sanazole to methemoglobin suggested the dissociation of nitro group in aqueous solution and denitration of molecules. Addition of sanazole to hypoxic tumor cell suspension resulted in the increase of nitrite content in tissue culture medium. CONCLUSION: Presented data suggest the ability of sanazole to produce NO that may be important in a probable mechanism for antitumor and immunomodulating properties of this radiosensitizer.