Study On The Expression Leveland Correlation Of Smads And MiRNA155 In Peripheral Blood Of Patients With Oral CGVHD

Objective: Chronic graft-versus-host-disease(cGVHD)is the most common complication after allogeneic hematopoietic stem cell transplantation(allo-HSCT),but its pathogenesis is still unclear.In this study,differences in Smads and miRNA155 expression levels in oral cGVHD patients and their correlation were studied,and bioinformatics analysis of miRNA155 was conducted to explore whether miRNA155 regulates the expression of Smads,and the relationship between the expression of Smads,miRNA155 and oral cGVHD.Methods:50 patients were recruited in the study,who had done the allo-HSCT in the department of hematology of the first affiliated hospital of Guangxi Medical University due to severe thalassemia or leukemia more than100 days and had no recurrence of the original disease and used anti-rejection drugs as prescribed.The medical history of all patients was collected.Among them,there were 18 patients with oral cGVHD,and oral characterization rating scale and VAS pain rating scale were recorded according to the patients' conditions.18 patients,after transplantation over 300 days,without oral andother organ cGVHD were selected from the above 50 patients and included in the non-oral cGVHD group.18 healthy volunteers matching the age and sex of oral cGVHD patients were selected as the healthy control group.All patients and healthy control group volunteers collected peripheral blood and saliva.Enzyme-linked immunosorbent assay(ELISA)was used to detect the protein contents of Smad2,Smad3,Smad4 and Smad7 in plasma and saliva of each group,and quantitative real-time RT-PCR(qRT-PCR)was used to detect the relative expression levels of Smad2,Smad3,Smad4,Smad7 mRNA in peripheral blood mononuclear cells(PBMC)and miRNA155 in plasma of each group.Target gene prediction,GO enrichment and KEGG signaling pathway analysis were performed on miRNA155 by bioinformatics.Results: 1.Clinical analysis of patients with oral cGVHD: the prevalence of oral cGVHD after allo-HSCT was 36%,and all patients showed hyperkeratotic white lines,which was most observed in both buccal mucosa and tongue.Among them,14 patients presented with ulcers and erosions,9 with dry mouth,5 with erythematous lesions,5 with chapped lips,3 with limitation of mouth opening,2 with lingual papillae atrophy,and 1 with herpes labialis.The oral characterization score of patients in the oral cGVHD group was 4.11±2.11,and the VAS score was 3.44±2.53,there was a significant positively correlation between both scores.2.Plasma Smads protein levels in the oral cGVHD group,non-oral cGVDH group and healthy control group: Smad2 expression was higher in the oral cGVHD group than in the other two groups(p < 0.05).Smad3 expression was significantly lower in the oral cGVHD group than in the other two groups(p < 0.05),while Smad4 and Smad7 were higher in the oral cGVHD group than in the healthy control group(p < 0.05).There were no statistically significantdifferences between the other groups.3.The expression of Smads mRNA in PBMC of the oral cGVHD group,the oral cGVDH group and the healthy control group: the expression of Smad2 mRNA and Smad4 mRNA in the oral cGVHD group was higher than that in the other two groups(p < 0.05),and the expression of Smad3 mRNA in the oral cGVHD group was lower than that in the other two groups(p < 0.05).The expression of Smad7 mRNA in oral cGVHD group was slightly higher than the other two groups,but the difference was not statistically significant.4.Expression of miRNA155 in plasma and bioinformatics analysis:miRNA155 had the lowest expression level in the oral cGVHD group,followed by the oral cGVHD group,and the highest expression in the healthy control group.The bioinformatic website predicted a total of 2524 target genes of miRNA155.While,there were 100 common target genes among the 3bioinformatics websites.The KEGG signaling pathway analysis revealed that 12 signaling pathways were identified.And there was a negative correlation between the expression of miRNA155 and Smad2.Conclusion: 1.Smad2,Smad4,and Smad 7 proteins were highly expressed in plasma of patients with oral cGVHD,while Smad3 was down-regulated.Smad2 mRNA and Smad4 mRNA were highly expressed in PBMC of patients with oral cGVHD,and Smad3 mRNA was down-regulated.miRNA155 is lower expressed in peripheral blood of patients with oral cGVHD.2.The expression of miRNA155 was negatively correlated with the expression of Smad2 protein,and miRNA155 may plays a role in the development of oral cGVHD by affecting the TGF-?/Smad signaling pathway.