Ever since proteomics was proven to be capable of characterizing a large number of differences in both protein quality and quantity, it has been applied in various areas of biomedicine, ranging from the deciphering molecular pathogenesis of diseases to the characterization of novel drug targets and the discovery of potential diagnostic biomarkers. Indeed, the biomarker discovery in human plasma is clearly one of the areas with enormous potential. However, without proper planning and implementation of specific techniques, the efforts and expectations may very easily be hampered. Numerous earlier projects aimed at clinical proteomics, characterized by exaggerated enthusiasm, often underestimated some principal obstacles of plasma biomarker discovery. Consequently, ambiguous and insignificant results soon led to a more critical view in this field. In this article, we critically review the current state of proteomic approaches for biomarker discovery and validation, in order to provide basic information and guidelines for both clinicians and researchers. These need to be closely considered prior to initiation of a project aimed at plasma biomarker discovery. We also present a short overview of recent applications of clinical proteomics in biomarker discovery., V. Tambor ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Biometric data are typically used for the purposes of unique identification of a person. However, recent research suggests that biometric data gathered for the purpose of identification can be analysed for extraction of additional information. This augments indicative value of biometric data. This paper illustrates the range of augmented indicative values of the data as well as identifies crucial factors that contribute to increased vulnerability of data subjects., Alžběta Krausová, Hananel Hazan, Ján Matejka., and Obsahuje bibliografické odkazy
As the number of cancer patients globally increases, a need for reliable biomarkers including circulating tumour DNA from liquid biopsy for diagnosis, prognosis and monitoring of the disease is rising. Currently, mainly tissue samples from biopsy are used, but there are certain limitations: firstly, it is an invasive technique, and secondly, in some cases it is almost impossible to obtain an acceptable tissue sample. This could be changed by using circulating cell-free DNA from liquid biopsy, which also gives the possibility of repeated examination. Here, we focus on the options of isolating circulating cell-free DNA from plasma samples using two isolation techniques: precision manual QIAamp Circulating Nucleic Acid Kit and automatic MagNA Pure Compact (MPC) using Nucleic Acid Isolation Kit I. Manual extraction gave significantly better yields of circulating tumour DNA (P < 0.05). This DNA also had less contaminants (organic compounds or proteins). DNA obtained by both tested methods of isolation is suitable for subsequent molecular genetic methods.
Sinonasal carcinomas are head and neck tumours arising from the nasal cavity and paranasal sinuses characterized by unfavourable outcome, difficult treatment, diagnosis and prognosis. MicroRNAs are key molecules in the regulation of development and progression of cancer and their expression profiles could be used as prognostic biomarkers, to predict the patients’ survival and response to treatment. In this study, we used quantitative real-time PCR with TaqMan® Advanced miRNA Assays to investigate the relative expression values of selected micro-RNAs in a unique set of formalin-fixed paraffin-embedded tissue samples obtained from 46 patients with sinonasal squamous cell carcinoma. Our results showed statistically significant up-regulation of three mature microRNAs: miR-9-5p (fold change: 6.80), miR-9-3p (fold change: 3.07) and let-7d (fold change: 3.93) in sinonasal carcinoma patients. Kaplan-Meier survival analysis and logrank test identified association between higher expression of miR-9-5p and longer survival of the patients (P = 0.0264). Lower expression of let-7d was detected in the patients with impaired survival, and higher expression of miR-137 was linked to shorter survival of the patients., We alsoidentified several correlations between expression of the studied microRNAs and recorded clinico-pathological data. Higher expression of miR-137 and lower expression of let-7d correlated with local recurrence (P = 0.045 and P = 0.025); lower expression of miR-9-5p and higher expression of miR-155-5p correlated with regional recurrence (P = 0.045 and P = 0.036). Higher expression of miR-9-3p correlated with occupational risk (P = 0.031), presence of vascular invasion (P = 0.013) and perineural invasion (P = 0.031). Higher expression of miR-155-5p was present in the samples originating from maxillary sinus (P = 0.011), cN1-3 classified tumours (P = 0.009) and G2-3 classified tumours (P = 0.017). In conclusion, our study supports the hypothesis of future prospect to use expression of miRNAs as prognostic biomarkers of squamous cell sinonasal carcinoma. In particular, miR-9-5p and miR-9-3p seem to be important members of the sinonasal cancer pathogenesis., and Corresponding author: Helena Kovaříková
Clear cell renal cell carcinoma (ccRCC) is very common and accounts for most kidney cancer deaths. While many studies are being conducted in finding the prognostic signatures of ccRCC, we believe that ferroptosis, which involves programmed cell death dependent on iron accumulation, has therapeutic potential in ccRCC. Recent research has shown that long noncoding RNAs (lncRNAs) are involved in ferroptosis-related tumour processes and are closely related to survival in patients with ccRCC. Hence, in this study we aim to further explore the role of ferroptosis-related lncRNAs (FRLs) in ccRCC, hoping to establish a signature to predict the survival outcome of ccRCC. We analysed transcriptome data from The Cancer Genome Atlas database (TCGA) and ferroptosis-related genes (FRGs) from FerrDb to identify FRLs using Pearson’s correlation. Lasso Cox regression analysis and multivariate Cox proportional hazards models screened seventeen optimal FRLs for developing prognostic signatures. Kaplan-Meier survival curves and ROC curves were then plotted for validating the sensitivity, specificity, and accuracy of the identified signatures. Gene Set Enrichment Analysis and CIBERSORT algorithm were deployed to explore the role of these FRLs in the tumour microenvironment. It was concluded that these models demonstrate excellent performance in predicting prognosis among patients with ccRCC, also indicating association with the clinicopathologic parameters such as tumour grade, tumour stage and tumour immune infiltration. In conclusion, our findings provide novel insights into ferroptosis-related lncRNAs in ccRCC, which are important targets for investigating the tumorigenesis of ccRCC.
miRNAs are small regulatory RNA molecules involved in posttranscriptional gene silencing. Their biosynthesis results in the
formation of duplex consisting of a leading and a passenger strand of mature miRNA. The leading strand exhibits the main activity but recent findings indicate a certain role of the passenger strand as well. Deregulated levels of miRNA were found in many types of cancers including colorectal cancer. miR-21 and miR-16 were indicated as possible markers of colorectal cancer, however, small attention to gender differences in their expression was paid so far. Therefore, the aim of our study was to investigate the expression of miR-21-5p, miR-21-3p, miR-16-5p and miR-16-3p in human colorectal cancer tissue and compare it to the adjacent tissues taken during surgery in men and women separately. Our results showed an up-regulation of
all measured miRNAs in tumor tissue compared to adjacent tissues. As expected, tumors and adjacent tissues exhibited a significantly higher expression of leading miRNAs compared to passenger strand of miR-21 and miR-16. The expression of leading and passenger strand of miR-21 and miR-16 positively correlated exhibiting the highest correlation coefficient in the distal tissue. The expression pattern showed gender-dependent differences, with higher levels of miRNA in men than in women. Our findings indicate a gender-related expression pattern of miRNA, which should be considered as an important factor in generating new prognostic or diagnostic biomarkers.
Oxidative stress markers are usually measured in plasma, a stable environment for biomarkers. Blood collection is invasive, but the use of alternative biofluids is limited, due to high variability. In this study, we aimed to establish reference values for oxidative stress markers in plasma, urine and saliva of adult, healthy mice and to identify some sources of variability. Samples were obtained from 41 female and 37 male adult, healthy mice of the CD-1 strain, aged 95-480 days, weighing 21-55 grams. Reference ranges of TBARS (thiobarbituric acid reactive substances), AOPP (advanced oxidation protein products), fructosamine, GSH/GSSG (reduced and oxidized glutathione) ratio, TAC (total antioxidant capacity), and FRAP (ferric reducing antioxidant power) were measured in plasma and urine, and TBARS, GSH/GSSG ratio, TAC and FRAP in saliva, using standard spectrophotometric and fluorometric methods. Salivary GSH/GSSG and urinary AOPP were higher in females. Urinary fructosamine, GSH/GSSG and FRAP were higher in males. Urinary TAC and FRAP negatively correlated with age, and urinary GSH/GSSG positively correlated with weight. We determined that urine and saliva can be obtained non-invasively from mice, in sufficient amounts for reliable oxidative status assessment. Further studies are needed to uncover whether these biofluids reflect systemic oxidative status in diseases.
Parenteral nutrition-associated liver disease (PNALD) is a severe
complication in patients completely dependent on parenteral
nutrition (PN). The gold diagnostic standard, liver biopsy, is
associated with significant health risk and therefore its use is
limited. MicroRNAs (miRNAs) are small non-coding regulatory
RNA molecules with highly tissue-specific expression and the
secreted miRNAs may serve as non-invasive diagnostic
biomarkers. The aim of this study was to evaluate the expression
of a panel of specific miRNAs associated with liver diseases of
different origin in PN-dependent adult patients in order to design
miRNA panel enabling to precise monitoring of PNALD
progression. Twelve PN-dependent patients with short bowel
syndrome (SBS) were monitored on three/four-month basis for
up to 24 months. Forty-five age- and sex-matched subjects
without any known liver pathology served as controls. Specific
miRNAs expression was determined by RT-qPCR using TaqMan
probes (Thermofisher). Liver function test parameters were
determined in certified clinical laboratories. Six of the tested
miRNAs exhibited significantly altered expression compared with
healthy controls, three of them (MIR122, MIR1273g, and
MIR500a) were upregulated while three were down-regulated
(MIR505, MIR199a, MIR139). MIR122 positively correlated with
serum AST and ALT activities while MIR1273g positively
correlated with serum CRP concentration and GGT activity.
MIR505, MIR199a, and MIR139 negatively correlated with serum
GGT activity. Fluctuation of these parameters well paralleled
serum miRNA concentrations in all patients throughout the whole
observation period. We identified six miRNAs whose serum
concentrations are significantly altered in PN-dependent patients
with PNALD and correlate with markers of inflammation,
cholestasis or hepatic injury. Their reliability as markers of PNALD
progression needs to be further evaluated.