Identification of a four-gene methylation biomarker panel in high-grade serous ovarian carcinoma.

Background The lack of effective biomarkers for the screening and early detection of ovarian cancer (OC) is one of the most pressing problems in oncogynecology. Because epigenetic alterations occur early in the cancer development, they provide great potential to serve as such biomarkers. In our study, we investigated a potential of a four-gene methylation panel (including CDH13, HNF1B, PCDH17 and GATA4 genes) for the early detection of high-grade serous ovarian carcinoma (HGSOC). Methods For methylation detection we used methylation sensitive high-resolution melting analysis and real-time methylation specific analysis. We also investigated the relation between gene hypermethylation and gene relative expression using the 2-ΔΔCt method. Results The sensitivity of the examined panel reached 88.5%. We were able to detect methylation in 85.7% (12/14) of early stage tumors and in 89.4% (42/47) of late stage tumors. The total efficiency of the panel was 94.4% and negative predictive value reached 90.0%. The specificity and positive predictive value achieved 100% rates. Our results showed lower gene expression in the tumor samples in comparison to control samples. The more pronounced downregulation was measured in the group of samples with detected methylation. Conclusions In our study we designed the four-gene panel for HGSOC detection in ovarian tissue with 100% specificity and sensitivity of 88.5%. The next challenge is translation of the findings to the less invasive source for biomarker examination, such as plasma. Our results indicate that combination of examined genes deserve consideration for further testing in clinical molecular diagnosis of HGSOC.

Next-Generation Sequencing Approach in Methylation Analysis of HNF1B and GATA4 Genes: Searching for Biomarkers in Ovarian Cancer.

DNA methylation is well-known to be associated with ovarian cancer (OC) and has great potential to serve as a biomarker in monitoring response to therapy and for disease screening. The purpose of this study was to investigate methylation of HNF1B and GATA4 and correlate detected methylation with clinicopathological characteristic of OC patients. The study group consisted of 64 patients with OC and 35 control patients. To determine the most important sites of HNF1B and GATA4, we used next-generation sequencing. For further confirmation of detected methylation of selected regions, we used high-resolution melting analysis and methylation-specific real-time polymerase chain reaction (PCR). Selected regions of HNF1B and GATA4 were completely methylation free in all control samples, whereas methylation-positive pattern was observed in 32.8% (HNF1B) and 45.3% (GATA4) of OC samples. Evaluating both genes together, we were able to detect methylation in 65.6% of OC patients. We observed a statistically significant difference in HNF1B methylation between samples with different stages of OC. We also detected subtype specific methylation in GATA4 and a decrease of methylation in late stages of OC. The combination of unmethylated HNF1B and methylated GATA4 was associated with longer overall survival. In our study, we employed innovative approach of methylation analysis of HNF1B and GATA4 to search for possible epigenetic biomarkers. We confirmed the significance of the HNF1B and GATA4 hypermethylation with emphasis on the need of selecting the most relevant sites for analysis. We suggest selected CpGs to be further examined as a potential positive prognostic factor.

[The Role of microRNA in head and neck cancer focusing on sinonasal carcinoma]. / Role mikroRNA u nádoru hlavy a krku se zamerením na sinonazální karcinom.

MicroRNAs are small (18-25 nt) noncoding RNA molecules that are part of gene expression regulation and influence tumorigenesis. They could possibly be used as biomarkers and therapeutic targets in cancer in the future.Head and neck cancer is the sixth most common malignancy worldwide. These also include sinonasal carcinoma, a rare disease arising in the epithelium of respiratory tract, which is very poorly studied from the molecular perspective.MicroRNAs that have influence on pathogenesis of head and neck tumors have been divided into three categories: microRNAs associated with invasiveness and metastatic processes, microRNAs operating as oncogenes and microRNAs associated with HPV status and smoking. We expect that the described microRNAs could be part of regulatory mechanisms also in sinonasal carcinoma.

Telomere length, oxidative and epigenetic changes in blood DNA of patients with exacerbated psoriasis vulgaris.

BACKGROUND: The pathogenesis of psoriasis vulgaris involves changes in DNA molecules, genomic instability, telomere attrition, and epigenetic alterations among them. These changes are also considered important mechanisms of aging in cells and tissues. OBJECTIVE: This study dealt with oxidation damage, telomere length and methylation status in DNA originating from peripheral blood of 41 psoriatic patients and 30 healthy controls. METHODS: Oxidative damage of serum DNA/RNA was determined immunochemically. Real-time PCR was used for the analysis of the telomere length. ELISA technique determined levels of 5-methylcytosine in blood cells' DNA. RESULTS: Oxidative damage of serum DNA/RNA was higher in patients than in controls (median, 3758 vs. 2286pg/mL, p<0.001). A higher length of telomeres per chromosome was found in patients whole-cell DNA than in controls (3.57 vs. 3.04 kilobases, p=0.011). A negative correlation of the length of telomeres with an age of the control subjects was revealed (Spearman's rho=-0.420, p=0.028). Insignificantly different levels of 5-methylcytosine in patients and controls were observed (33.20 vs. 23.35%, p=0.234). No influences of sex, smoking, BMI, PASI score, and metabolic syndrome on the methylation status were found. STUDY LIMITATIONS: i) A relatively small number of the participants, particularly for reliable subgroup analyses, ii) the Caucasian origin of the participants possibly influencing the results of the parameters determined, and iii) Telomerase activity was not directly measured in serum or blood cells. CONCLUSION: The study demonstrated increased levels of oxidized DNA/RNA molecules in the serum of patients with exacerbated psoriasis vulgaris. The results were minimally influenced by sex, the presence of metabolic syndrome, or cigarette smoking. In the psoriatic blood cells' DNA, the authors observed longer telomeres compared to healthy controls, particularly in females. Insignificantly higher global DNA methylation in psoriasis cases compared to the controls indicated marginal clinical importance of this epigenetic test performed in the blood cells' DNA.

DNA hypermethylation of CADM1, PAX5, WT1, RARß, and PAX6 genes in oropharyngeal cancer associated with human papillomavirus.

Recently, an increasing incidence of HPV-induced oropharyngeal squamous cell carcinoma (OPSCC) has been observed. Moreover, locoregionally advanced stages require a combined modal approach, and the prognosis is poor. Therefore, it is essential to find early diagnostic and prognostic biomarkers. DNA methylation changes play a crucial role in the process of carcinogenesis and are often investigated as promising biomarkers in many types of cancer. For analysis of DNA methylation levels of selected tumour suppressor genes in HPV-positive and HPV-negative samples (including primary tumours and corresponding metastases of metastasizing OPSCCs, primary tumours of non-metastasizing OPSCCs, and control samples), methylation-specific MLPA and methylation-specific high-resolution melting analyses were used. A significant difference in methylation between OPSCCs and the control group was observed in WT1, PAX6 (P < 0.01) and CADM1, RARß (P < 0.05) genes. CADM1 and WT1 hypermethylation was detected mostly in HPV-positive samples; all but one HPV-negative samples were unmethylated. Moreover, hypermethylation of PAX5 gene was observed in metastases compared with control samples and was also associated with shorter overall survival of all patients (P < 0.05). Associations described herein between promoter methylation of selected genes and clinicopathological data could benefit OPSCC patients in the future by improvement in screening, early detection, and prognosis of the disease.

Significantly Altered Serum Levels of NAD, AGE, RAGE, CRP, and Elastin as Potential Biomarkers of Psoriasis and Aging-A Case-Control Study.

BACKGROUND: This study aims to investigate potential markers of psoriasis and aging, and to elucidate possible connections between these two processes. METHODS: The serum samples of 60 psoriatic patients and 100 controls were analysed, and the levels of four selected parameters (AGEs, RAGE, NAD, and elastin) were determined using commercial ELISA kits. Serum C-reactive protein was assayed using an immune-nephelometry method. FINDINGS: Among the patients, the levels of CRP, AGEs, and RAGE were all increased, while the levels of NAD were reduced when compared to the control group. A negative correlation between the levels of AGEs and NAD was found. A negative correlation between age and the NAD levels among the control group was observed, however among the patients the relationship was diminished. While there was no difference in the levels of native elastin between the patients and the controls, a positive correlation between the levels of native elastin and age and a negative correlation between the levels of native elastin and the severity of psoriasis were found. CONCLUSIONS: The results of our study support the notion of psoriasis and possibly other immune-mediated diseases accelerating the aging process through sustained systemic damage. The serum levels of CRP, NAD, AGEs, and RAGE appear to be promising potential biomarkers of psoriasis. The decrease in the serum levels of NAD is associated with (pro)inflammatory states. Our analysis indicates that the levels of native elastin might strongly reflect both the severity of psoriasis and the aging process.

MicroRNA Deregulation in Papillary Thyroid Cancer and its Relationship With BRAF V600E Mutation.

BACKGROUND: MicroRNAs (miRNAs) are non-coding regulatory molecules 18-25 nucleotides in length that act as post-transcriptional regulators of gene expression. MiRNAs affect various biological processes including carcinogenesis. Deregulation of miRNAa expression has been described in a variety of tumors including papillary thyroid carcinoma (PTC). The aim of the present study was to investigate the role of selected miRNAs in PTC and find associations between miRNA expression and the BRAF (V600E) mutation. MATERIALS AND METHODS: The study group comprised a total of 62 patients with surgically treated PTC. The control group consisted of 30 patients with nodular goitre that were surgically treated in the same time period. The expression status of miR-146b, miR-181a, miR-187, miR-221 and miR-222 was determined using quantitative real-time PCR. BRAF mutation analysis was performed by PCR with reverse hybridization. RESULTS: MiR-146b, miR-181a, miR-187, miR-221 and miR-222 were up-regulated in PTC compared to normal thyroid gland tissue of the same patient. MiR-146b, miR-187, miR-221 and miR-222 were also up-regulated in PTC compared to nodular goitre. The recurrent tumors were statistically significantly associated with up-regulation of miR-221. The mutation V600E of BRAF gene was significantly associated with up-regulation of miR-146b and with down-regulation of miR-187. CONCLUSION: Over-expression of selected miRNAs in PTC compared to normal thyroid gland tissue and nodular goitre was found. Moreover, miR-221 may serve as a prognostic marker as its over-expression was significantly associated with recurrent tumors.

Aberrant methylation of PCDH17 gene in high-grade serous ovarian carcinoma.

BACKGROUND: Aberrant DNA methylation of protocadherins (PCDHs) has been associated with development and progression of various types of cancer. It could represent possible direction in the search for critically needed tumor biomarkers for ovarian cancer. OBJECTIVE: To investigate methylation of δ2 group of non-clustered PCDHs in high-grade serous ovarian carcinoma (HGSOC) tissue in comparison with control tissue. METHODS: We used next-generation sequencing for detecting regions with the most altered methylation. For further confirmation of discovered alterations we used methylation-sensitive high-resolution melting analysis. RESULTS: PCDH17 methylation was detected in almost 70% of HGSOC patients without any methylation in the group of control samples and was found both in the late stage tumors as well as in the early stage ones. Other selected PCDHs did not show any relevant changes in methylation. Subsequent gene expression analysis of PCDH17 revealed decreased expression in all of the tumor samples in comparison to the control ones. Statistically significant negative correlation was found between methylation and levels of expression suggesting potentially methylation-based silencing. CONCLUSIONS: Methylation of PCDH17 could play an important role in development and progression of HGSOC and has potential to become a target in the search for new clinical biomarkers.

Elevated DNA methylation in malignant tumors of the sinonasal tract and its association with patient survival.

BACKGROUND: Epigenetic modifications have been recognized as an important mechanism underlying carcinoma progression. DNA methylation plays an important role in cancer biology and represents potentially heritable changes in gene expression that do not involve DNA sequence. The aim of this study was to investigate promoter methylation of selected genes in sinonasal carcinoma by comparison with noncancerous sinonasal tissue. METHODS: To search for epigenetic events (methylation in 25 tumor suppressor genes) we used MS-MLPA (Methylation-specific multiplex ligation-dependent probe amplification) to compare methylation status of 59 formalin fixed, paraffin embedded tissue samples of sinonasal carcinomas with 18 control samples. The most important changes in methylation were confirmed using MSP (Methylation specific PCR). Detected alterations in methylation were compared with clinicopathological characteristics. RESULTS: Using a 20% cut-off for methylation (MS-MLPA), we found significantly higher methylation in GATA5 (P=0.0005), THSB1 (P=0.0002) and PAX5 (P=0.03) genes in the sinonasal cancer group compared to the control group. Methylation in five or more genes was associated with impaired overall survival (P=0.017). CONCLUSION: These findings provide evidence that alterations in methylation profile may be one of the major mechanisms in sinonasal carcinogenesis. In addition, changes in methylation could potentially be used as prognostic factors of sinonasal carcinoma and may have implications for future individualized therapy based on epigenetic changes.

Telomere length, oxidative and epigenetic changes in blood DNA of patients with exacerbated psoriasis vulgaris

Abstract Background The pathogenesis of psoriasis vulgaris involves changes in DNA molecules, genomic instability, telomere attrition, and epigenetic alterations among them. These changes are also considered important mechanisms of aging in cells and tissues. Objective This study dealt with oxidation damage, telomere length and methylation status in DNA originating from peripheral blood of 41 psoriatic patients and 30 healthy controls. Methods Oxidative damage of serum DNA/RNA was determined immunochemically. Real-time PCR was used for the analysis of the telomere length. ELISA technique determined levels of 5-methylcytosine in blood cells' DNA. Results Oxidative damage of serum DNA/RNA was higher in patients than in controls (median, 3758 vs. 2286 pg/mL, p < 0.001). A higher length of telomeres per chromosome was found in patients whole-cell DNA than in controls (3.57 vs. 3.04 kilobases, p = 0.011). A negative correlation of the length of telomeres with an age of the control subjects was revealed (Spearman's rho = -0.420, p = 0.028). Insignificantly different levels of 5-methylcytosine in patients and controls were observed (33.20 vs. 23.35%, p = 0.234). No influences of sex, smoking, BMI, PASI score, and metabolic syndrome on the methylation status were found. Study limitations i) A relatively small number of the participants, particularly for reliable subgroup analyses, ii) the Caucasian origin of the participants possibly influencing the results of the parameters determined, and iii) Telomerase activity was not directly measured in serum or blood cells. Conclusion The study demonstrated increased levels of oxidized DNA/RNA molecules in the serum of patients with exacerbated psoriasis vulgaris. The results were minimally influenced by sex, the presence of metabolic syndrome, or cigarette smoking. In the psoriatic blood cells' DNA, the authors observed longer telomeres compared to healthy controls, particularly in females. Insignificantly higher global DNA methylation in psoriasis cases compared to the controls indicated marginal clinical importance of this epigenetic test performed in the blood cells' DNA.

Deregulation of selected microRNAs in sinonasal carcinoma: Value of miR-21 as prognostic biomarker in sinonasal squamous cell carcinoma.

BACKGROUND: Tumors occurring in the sinonasal area are characterized by unfavorable outcome due to difficult diagnosis, treatment, and prognosis of the disease corresponding with the anatomic complexity of the area. METHODS: We used quantitative real-time polymerase chain reaction (PCR) to compare relative expression of miR-21, miR-141, and miR-200c in 70 formalin-fixed, paraffin-embedded samples of sinonasal carcinoma tissue (majority of squamous cell carcinoma [SCC] samples) with 17 control samples of sinonasal tissue. RESULTS: Our data showed significant upregulation of miR-21 in sinonasal cancer tissue. Expression levels of miR-141 and miR-200c were below detectable levels in both sinonasal cancer samples and healthy tissue. Kaplan-Meier analysis with log-rank survival showed that patients with SCC with high expression of miR-21 (highest quartile) had impaired survival close to reaching statistical significance (P = .0630). CONCLUSION: Our results suggest that miR-21 upregulation is involved in tumorigenesis of sinonasal carcinoma and that it is associated with poor prognosis. Thus, miR-21 could be used as a valuable prognostic biomarker.