Introduction: Urinary bladder cancer is a serious oncological problem that is the cause of many deaths worldwide. The processes of metastasis and origination of local tumor invasion depend on the extracellular matrix (ECM) degradation. The cancer microenvironment, particularly the ECM, may be considered a key factor in cancer progression. Matrix metalloproteinases (MMPs) are classified as the main factors responsible for the degradation of ECM components. Therefore, the aim of the study was to evaluate the expression and activity of matrix metalloproteinase 2 and 9 (MMP-2 and MMP-9) in urinary bladder cancer according to different stages. Material and methods: Urinary bladder tissue samples were analyzed. Cancer patients were divided into two groups: low-grade tumors (LG; Group I) and high-grade tumors (HG; Group II). Control tissue was obtained from the opposite site to the tumor. MMPs content and activity (actual and specific) were evaluated using ELISA and Western blot methods, respectively. Results: Both MMPs are present in high and low molecular complexes in healthy or bladder cancer tissues. The content of MMP-9 is enhanced in comparison with MMP-2, particularly in HG cancer tissue. The actual activity of MMP-2 was highest in LG cancer tissue whereas the actual activity of MMP-9 was highest in HG cancer. Specific activity of both MMPs was highest in LG cancer, but the activity of MMP-9 was higher in comparison with MMP-2. Conclusions: In conclusion, the content and specific activity of MMP-9 were increased in comparison with MMP-2. The revealed differences in content and activity of both MMPs demonstrate their different participation in ECM remodeling at different stages of cancer development. Moreover, it seems that MMP-9 has higher clinical utility than MMP-2 as a potential therapeutic option and a diagnostic biomarker of urinary bladder cancer.

The purpose of this study was to create a new, highly selective biosensor, which uses surface plasmon resonance as a detection method for the quantitative determination of the matrix metalloproteinase-1. The main part of the biosensor is an immobilized rabbit anti-human matrix metalloproteinase-1 antibody, which binds the enzyme from the sample. The analytical response signal of the biosensor is in the range of 0.05–20.00 ng ml⁻¹. The detection limit is 9 pg ml⁻¹, and the limit of quantification is 18 pg ml⁻¹. The biosensor was used to measure the matrix metalloproteinase-1 concentration in the blood plasma of healthy persons and patients with bladder cancer with good results (good tolerance of the potential interferents). To validate the new analytical method, measurements of serum matrix metalloproteinase-1 concentration in the biological samples by Enzyme-Linked Immunosorbent Assay (ELISA) were conducted. Good correlation between these two methods was found. The developed biosensor can be successfully used for the quantitative determination of matrix metalloproteinase-1 in laboratories.

The aim of this study was to develop a new, label-free, highly selective Surface Plasmon Resonance Imaging biosensor for the quantitative determination of matrix metalloproteinase-2. Matrix metalloproteinase-2 specific inhibitor, ARP 101, was used as the receptor, the main part of the biosensor, which bound the enzyme from the sample. The analytical response signal (linear part of the calibration curve) of the developed biosensor was in the range of 1.0–100.0 ng ml⁻¹. Its detection limit was 3.9 ng ml⁻¹, and the limit of quantification was 7.7 ng ml⁻¹. The selectivity, precision and accuracy of the new biosensor were acceptable. The biosensor was used for the quantitative determination of matrix metalloproteinase-2 in the blood plasma of healthy persons and in the plasma of burned children, with good results (good tolerance for potential interferents). Also, to validate the new biosensor, the measurements of plasma matrix metalloproteinase-2 concentration in the biological samples by Enzyme-Linked Immunosorbent Assay were conducted. It was found that the correlation between these two methods was good.

Ubiquitin-mediated protein degradation plays a crucial role in various cellular processes, including signal transduction, cell differentiation, and stress response. Ubiquitin C-terminal hydrolase 1 (UCHL1) is a unique deubiquitinating enzyme that has both hydrolase and ligase activities. The aim of this study was the determination of UCHL1 concentration in serum of children with appendicitis, before and after the surgery. Material and methods: 42 children with acute appendicitis, who were managed at the Pediatric Surgery Department, between 2013 and 2014, were randomly included into the study (age 9 months up to 14 years, mean age 2.5 + 1 years). There were 15 girls and 27 boys. 18 healthy, age-matched subjects, admitted for planned surgeries served as controls. Exclusion criteria were: severe preexisting infections, immunological or cardiovascular diseases that required long-term medication, and complicated cases of appendicitis with perforation of appendix and/or peritonitis. Results: The UCHL1 concentrations in the blood plasma of patients with acute appendicitis, were highest before the surgery, and were above the range of concentrations measured in controls, the difference was statistically significant. The UCHL1 concentration measured 24 and 72 h after the operation, slowly decreased over time, and still did not reach the normal range, when compared with the concentration measured in controls (p < 0.05). Conclusions: UCHL1 concentration may reflect the metabolic response to acute state inflammation, and the process of gradual ebbing of the inflammation. The method of operation—classic open appendectomy, or laparoscopic appendectomy, does not influence the general trend in UCHL1 concentration in children with appendicitis. There is strong negative correlation between prealbumin and UCHL1 concentrations.