RESUMO
Background: Most cancer studies focus on exploring non-invasive biomarkers for cancer detection. In the present study, we sought to investigate the expression level of microRNA-21 [miR-21], as a potential diagnostic marker, in serum and stool samples from 40 patients with colorectal cancer [CRC] and 40 healthy controls
Methods: Quantitative real-time RT-PCR was applied to determine the relative expression level of miR-21 in serum and stool. At the same time, the sensitivity and specificity of this marker was evaluated by receiver operating characteristic [ROC] curve analysis
Results: miR-21 expression levels of serum and stool were up-regulated 12.1 [P<0.05, 95% CI: 5.774-34.045] and 10.0 [P<0.05, 95% CI: 0.351-16.260] times in CRC patients, respectively, when compared to the control group. The sensitivity and specificity of miR-21 was found to be 86.05% and 72.97%, respectively [an area under the ROC curve [AUC] of 0.783]. The stool miR-21 level in CRC patients was much higher than that in the healthy controls, showing a sensitivity of 86.05% and a specificity of 81.08% [AUC: 0.829]. The expression level of miR-21 in stool was able to significantly distinguish CRC tumor, node, metastasis stages III-IV from stages I-II, with a sensitivity and specificity of 88.1% and 81.6%, respectively [AUC: 0.872]
Conclusion: The results of this study indicated that miR-21 expression levels in serum and stool can be considered as a potential diagnostic biomarker for the diagnosis of CRC patients. However, more studies are required to confirm the validity of miR-21 as a valuable non-invasive diagnostic tool for CRC
RESUMO
Multiple sclerosis [MS] is a chronic autoimmune disease due to demyelination of the central nervous system. It is believed that cytokines are involved in the pathogenesis of MS. The interleukin-2 [IL2] gene is powerful functional candidate that is involved in immune regulation and operation. In this study, for the first time, we investigated the effect of -475 A/T and -631 G/A IL2 polymorphisms on MS disease in Iranian patients. In this case-control study, 100 MS patients [mean age: 32.95 +/- 6.51 years, age range: 20-42 years] selected according to McDonald criteria, and 100 ethnically, sex and age matched healthy controls [mean age: 29 +/- 7.8 years, age range: 20-52 years] with no personal or family history of autoimmune diseases were studied. The restriction fragment length polymorphism-polymerase chain reaction [RFLP-PCR] method was applied to define different alleles and genotypes of IL2 promoter single nucleotide polymorphism -475 A/T as well as -631 G/A among individuals. chi [2] was calculated and Fisher's exact test was applied to analyze the obtained data. The value of p <0.05 was considered significantly. Evaluation of the -475 IL2 revealed that T allele and A/T genotype are present in 2% and 4% of MS patients, respectively, whereas T allele was absent in control samples. The comparison between alleles and genotypes in MS patients and healthy controls was not significant [p=0.1]. For the -631 position, 1% and 2% of MS patients carried A allele and A/G heterozygote genotypes, respectively. All control samples had G allele and G/G genotype. The differences between patients and controls were not significant [p=0.4]. Moreover, our results showed a very low frequency of T at -475 and A at -631 IL2 position in each of the two groups. Both -475 and -631 IL2 polymorphisms were higher in MS patients as compared to controls, but the frequency differences were not significant. Based on these data, it is suggested that the -475 and -631 IL2 polymorphisms as functional promoter position may be involved in IL2 expression and regulation. To find out the exact effect of the mentioned SNPs on susceptibility to MS, study on a larger sample size is suggested