Analysis of SDC2 gene promoter methylation in whole blood for noninvasive early detection of colorectal cancer.

Objectives: Considering the limitations of the current approaches to colorectal cancer (CRC) screening, scientists strived to find noninvasive and more powerful biomarkers for the early diagnosis of CRC. Nowadays, there are different sources of biomarkers for CRC diagnosis. Blood-based samples including circulating cell-free tumor DNA (ctDNA) and DNA extracted from leukocytes in peripheral blood might be promising sources of noninvasive cancer biomarkers such as cancer-specific methylation patterns. In this study, we aimed to evaluate the noninvasive early diagnosis of CRC via quantitative promotor methylation analysis of SDC2 gene in whole blood. Materials and Methods: Sixty-five CRC patients and 65 healthy participants were enrolled to assess promoter methylation of SDC2 gene in whole blood using the methylation quantification endonuclease-resistant DNA (MethyQESD) technique. Results: Our findings demonstrated drastic hypermethylation of SDC2 in blood samples from CRC subjects (37.91%) compared with non-malignant individuals (17.02%) (P < 0.001). The sensitivity for detection of CRC by methylation of SDC2 was 81.54%, with a specificity of 69.23%. The ROC curve analysis demonstrated that the AUC was 0.847 (P < 0.001), indicating that the status of SDC2 promoter methylation in whole blood is an excellent biomarker of CRC diagnosis. Furthermore, our results showed that methylation level in CRC patients significantly increased in higher tumor stages, demonstrating that an increased percentage of methylation is correlated with tumor progression (P < 0.001). Conclusion: SDC2 promoter methylation status in blood samples is a valuable cancer biomarker and holds high power and accuracy in distinguishing CRC patients from healthy subjects in the early stages of the disease.

A functional microRNA binding site variant in IL-23R gene in systemic lupus erythematosus and rheumatoid arthritis: is there any correlation?

BACKGROUND: IL-23 receptor (IL-23R) dysregulation has been shown to have critical roles in pathogenesis of different autoimmune diseases including systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) via suppression of regulatory T cells (Tregs) as well as differentiation, expansion, and survival of T helper 17 (Th17) cells, followed by upregulation of interleukin 17 (IL-17). Here, we assessed the association of a functional microRNAs (miRNAs)-related single nucleotide polymorphism (miR-SNPs: rs10889677) in IL-23R, which was correlated with its overexpression and increased risk for SLE and RA in the Iranian population. METHODS: Genotype and allele distribution of rs10889677 variant were investigated in 105 RA patients, 100 SLE cases and 105 healthy controls via polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP) method. RESULTS: Our findings suggested that AA genotype, but not AC genotype, was associated with increased risk of RA (AA vs. CC; OR: 3.27; 95%CI [1.467-7.551]). The allele A was more frequent in RA group compared to controls (A allele vs. C allele; OR: 1.92; 95%CI [1.282-2.894]). This common variant was not significantly correlated with SLE risk in our population (P > 0.05). However, stratification analysis indicated that RA patients with AA genotype show higher serum concentration levels of C-reactive protein (CRP) (P: 0.008). No obvious correlation was noticed between different genotypes in SLE cases, except for a slight difference in terms of oral ulcer manifestation incidence (P: 0.038). CONCLUSION: This study suggests a significant relationship between rs10889677 variant in IL-23R with increased risk of RA and some clinical features in RA and SLE patients.