ABSTRACT
Microsatellite instability (MSI) is a unique molecular alteration that is due to a defective DNA mismatch repair (MMR) system. Approximately, 15-20 % of sporadic colorectal cancers (CRC) display MSI. Determination of MSI status in CRC has prognostic and predictive implications. Additionally, detecting MSI is used diagnostically for tumor detection and classification. The present study analyzed a panel of five mononucleotide markers, BAT-25, BAT-26, NR-21, NR-22 and NR-27, amplified in a single multiplex PCR reaction to evaluate MSI status in CRC patients. Genomic DNA from 50 CRC and paired adjacent normal tissues was used for PCR-based MSI analysis. Our finding showed microsatellite instability in 36 % of specimens. Instability with differences in allele lengths was observed in the tumoral DNA compared to the tumor-free margin DNA sample. The frequency of instability in NR-21, BAT-26 and BAT-25 markers were more than others; their frequency were 35.48 %, 29.03 %, and 22.58 %, respectively. In conclusion, the NR-21, BAT-26, and BAT-25 were the most useful markers for discriminating cancer tissue from normal, therefore these markers have demonstrated promising potential for determining MSI status in patients with sporadic colorectal cancer.
ABSTRACT
Colorectal cancer (CRC) is one of the most common malignancies, and the third leading cause of cancer mortality worldwide. Timely detection of CRC in patients with earlier stages provides the highest rate of survival. Epigenetic alterations are important in the occurrence and progression of CRC, and represent the primary modifications of cancer cells. Therefore, detection of these alterations in CRC cases are thought to hold great promise as diagnostic biomarkers. It has been shown that the SEPT9 and NTRK3 genes are aberrantly methylated and their detection can be used as biomarkers for early diagnosis of CRC. The present study analyzed promoter methylation status of these genes in CRC patients. Genomic DNA was extracted from 45 CRC and paired adjacent healthy tissues and undergone bisulfite conversion, and the methylation status of NTRK3 and SEPT9 were defined using the MS-HRM assay. Our results showed that there are statistically significant differences in methylation status of NTRK3 and specially SEPT9 between CRC and adjacent normal tissues (P<0.001). High sensitivity and specificity for a specific location in SEPT9 gene promoter as a diagnostic biomarker was observed. SEPT9 promoter hypermethylation may serve as a promising biomarker for the detection of CRC development. However, to validate the biomarker potential of NTRK3 there is a requirement for further investigation.
ABSTRACT
OBJECTIVE: To compare the complications among preterm infants treated with two different natural surfactants. METHODS: In a randomized clinical trial, 150 preterm infants with Respiratory distress syndrome (RDS) treated with exogenous surfactant, were enrolled in the study. Group A consisted of 79 neonates that received poractant (curosurf). Seventy one newborn infants in group B were treated with beractant (Survanta). RESULTS: The mean gestational age for group A and B were 29.40+/-2.90 wk and 29.50+/-2.73 wk (P=0.82), respectively. The demographic and clinical variables were similar in both groups. The mean duration of intubation (as a primary outcome) was significantly shorter in infants treated with poractant (3.13+/-1.80 vs 4.06+/-2.7 days p=0.05). The mean duration of need for oxygen and hospitalization of patients in group A and B were 17.73+/-22.25 vs 19.14+/-17.85 days (p=0.67) and 24.89+/-26.41 vs 29.14+/-23.54 days (p= 0.32), respectively. There was no significant difference between groups with respect to mortality and morbidity, including pulmonary hemorrhage, intraventricular hemorrhage (IVH), patent ductus arteriosus, sepsis, and bronchopulmonary dysplasia (secondary outcome). CONCLUSIONS: In this study, infants who received poractant had shorter duration of intubation than infants treated with beractant, without any difference in the duration of oxygen therapy or hospitalization. There was no significant superiority of poractant over beractant.
