Current knowledge of tumor biology offers many “targets” for therapeutic intervention. The molecular basis of many processes that play a role in the pathogenesis of colorectal cancer has been identified. One part of colorectal cancer clinical trials is focused on testing substances in a group of patients with tumors in which the TGF-β signalling pathway is hyperactivated. The TGF-β/SMAD signalling pathway members are considered important markers; however, genetic, proteomic, or metabolomic analyses still yield controversial results. According to our results, TGF-βRII, and SMAD4 can be used in monitoring CRC progression. With increasing CRC stage, TGF-βRII expression decreases and SMAD4 expression increases. The patients with TGF-βRII expression lower than 700 pg/ml had a slightly lower survival time (28.103 months) than patients with higher TGF-βRII expression (31.620 months). Conversely, patients with SMAD4 expression lower than 200 pg/ml had a higher survival rate (30.979 months) than patients with higher expression (26.316 months). Regarding TGF-β1 expression, the patient´s survival assessment determined no significant difference between patients with high or low tissue TGF-β1 expression. A personalized approach and consideration of a wide range of factors are important when using these markers in treatment assessment.

Background and objectives: Melanin, which has a confirmed role in melanoma cell behaviour, is formed in the process of melanogenesis and is synthesized from tryptophan, L-tyrosine and their metabolites. All these metabolites are easily detectable by chromatography in urine. Materials and Methods: Urine samples of 133 individuals (82 malignant melanoma patients and 51 healthy controls) were analysed by reversed-phase high-performance liquid chromatography (RP-HPLC). The diagnosis of malignant melanoma was confirmed histologically. Results: Chromatograms of melanoma patients showed increased levels of 5,6-dihydroxyindole-2-carboxylic acid, vanilmandelic acid, homovanilic acid, tryptophan, 5-hydroxyindole-3-acetic acid, and indoxyl sulphate compared to healthy controls. Concentration of indoxyl sulphate, homovanilic acid and tryptophan were significantly increased even in the low clinical stage 0 of the disease (indoxyl sulphate, homovanilic acid and tryptophan in patients with clinical stage 0 vs. controls expressed as medium/ interquartile range in µmol/mmol creatinine: 28.37/15.30 vs. 5.00/6.91; 47.97/33.08 vs. 7.33/21.25; and 16.38/15.98 vs. 3.46/6.22, respectively). Conclusions: HPLC detection of metabolites of L-tyrosine and tryptophan in the urine of melanoma patients may play a significant role in diagnostics as well as a therapeutic strategy of melanoma cancer.

Non-invasive possibilities of predicting cardiovascular risk and monitoring the treatment and progression of coronary artery disease (CAD) are important subjects of cardiovascular research. Various inflammatory markers have been identified as potential biomarkers of CAD, including interleukin-6 (IL-6), lipocalin-2 (LCN-2), growth differentiation factor 15 (GDF-15), and T cell immunoglobulin and mucin domain-3 (TIM-3). This research aims to identify their utility in the investigation of CAD severity and progression. The basic anthropometric parameters, as well as the levels of urea, creatinine, CRP, leukocytes, fibrinogen, and biomarkers of inflammation, were measured in 130 patients who underwent coronary angiography. In male patients, divided according to findings on coronary angiography, we observed an increasing expression of GDF-15 with increasing stenosis (with worsening findings). In females, we observed increasing fibrinogen expression with increasing stenosis, i.e., findings on coronary angiography. Correlation analysis did not confirm the relationship between TIM-3, LCN and 2, IL-6 and the severity of findings obtained by coronary angiography; however, the correlation of TIM-3 and LCN-2 expression was positive with the finding, and the correlation of IL-6 with the finding was surprisingly negative. Understanding the role of these inflammatory markers in CAD can be helpful in risk stratification, guiding therapeutic strategies, and monitoring treatment responses in patients with CAD.

Zymography is an electrophoretic method in which proteins are separated in a polyacrylamide gel in the presence of sodium dodecyl sulfate (SDS-PAGE). This method is used for the detection of enzymatic activity and molecular characterization of proteins. In contrast to the standard SDS-PAGE method, a substrate is incorporated into the gel during zymography, which is subsequently cleaved by target proteases. Many studies have focused on the development and progression of inflammatory diseases affecting the gastrointestinal tract, emphasizing the role of the largest group of proteases, matrix metalloproteinases (MMPs). The most used classification of this group of enzymes (by researchers in MMP biology) is based in part on the historical evaluation of the substrate specificity of MMPs and in part on the cellular localization of MMPs. MMPs are thus classified into the groups of collagenases, gelatinases, stromelysins, matrilysins, membrane-type MMPs (MT-MMPs), and others. An important group of MMPs are gelatinases which are involved in the breakdown of collagen type IV and gelatin of extracellular matrix and participate in the regulation of various physiological or pathological processes such as morphogenesis, angiogenesis, tissue repair, cirrhosis, arthritis, and metastasis. The present study's objective was to determine the amount of active MMP-9 and MMP-2 forms in tissue samples using zymography. The patient group was according to histology findings divided into the benign tumor (control) group (8 patients), and the malignant tumor group (24 patients). The respondents in the malignant tumor group were further divided according to the standard TNM classification. The results of this study confirmed that MMP-2, unlike MMP-9, can be used as a prognostic biomarker of CRC, because only the expression of active MMP-2 confirmed statistically significant differences between individual stages of CRC. Moreover, MMP-2 seems to play a more important role in higher stages of CRC. Substantial disparities in the determination of active MMPs between the observed groups support the assumption for the integration of zymography into clinical diagnostics of CRC together with molecular and other studies.

Purpose: The development of sensitive and non-invasive biomarkers for the early detection of CRC and determination of their role in the individual stages of CRC. Methods: MMP-9 expression in serum and tissue, and BDNF expression in plasma were detected using the ELISA method. MMP-9 and BDNF in the tissue were also determined by immunohistochemical staining. Results: To assess the balance between changes in survival and tumor progression, we compared BDNF/MMP-9 ratios in tissues of living and deceased individuals. The tissue BDNF/MMP-9 ratio (evaluated immunohistochemically) decreased significantly with the progression of the disease in living patients. The BDNF/MMP-9 ratio was statistically significantly reduced in stages II and III compared to the benign group. However, in deceased individuals, the ratio showed an opposite tendency. Conclusion: The determination of the tissue BDNF/MMP9 ratio can be used as a prognostic biomarker of CRC.

The trend of modern clinical biochemistry is to emphasize the composition and the quality of lipoproteins over their quantity. The serum lipoprotein fractions and subfractions were analyzed by the Lipoprint Lipoprotein Subfractions Testing System, the parameters of lipid profile, as total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C) and triacylglycerides (TAG) were determined by an automated selective biochemical analyzer. Our results showed a significantly lower concentration of cholesterol in the LDL fractions 1 and 2 and in the HDL fractions 8 to 10 in Roma compared to the majority population. The most significant differences between Roma and the majority population when considering body mass index (BMI), waist-to-hip ratio and the index of central obesity were in very low-density lipoproteins (VLDL), intermediate-density lipoproteins, fraction A (IDL-A) and LDL-2. The last two listed were significantly higher in the majority population. VLDL was significantly higher in overweight or obese Roma men and in Roma men with central obesity compared to men from the majority population, as well as in Roma women with normal weight and physiological waist-to-hip ratio compared to the women from majority population. Our study is among the first describing the distribution of lipoprotein subfractions in different ethnic groups.