Screening Of Piwi-interacting RNA In Cancer Stem-like Cell And Its Expression In Childhood Nephroblastoma

Objective: To investigate the expression and clinical significance of Piwi-interacting RNA(piRNA)in childhood nephroblastoma.Methods: The differential piRNAs of Piwil2-iCSC(Piwil2 reprogramming human fibroblast)were screened by highthroughputsequencing.The target genes were predicted by miRanda and performed by gene function(GO)analysis.The differentiallypiRNA and its target gene were detected by qRT-PCR in tumortissues and normal kidney tissues of 34 children with nephroblastoma.The correlation between differential expressedpiRNAs and target genes with clinicopathological charateristics of nephroblastoma was analyzed.Results: Through high-throughput sequencing,230 differential piRNAs were screened out and 43 target genes were predicted by miRanda.The GeneOntology analysis showed that the biological processes of target gene was mainly involved in regulating the calcium concentration of cells and its molecular function was mainly involved in the activity of ATPase and poly(A)RNA binding.The expression of five unknown differentially expressed piRNAs and their target genes were selected to be detected in nephroblastoma and normal kidney tissues.The expression of NU13(13th unknown up-regulated piRNA)was significantly down-regulated(P<0.01),and which of its target gene NOP56 ribonucleoprotein hadnosignificance(P=0.58);The expression of NU9(9th unknown up-regulated piRNA)was down-regulated(P<0.01),and which of its target gene 40 S ribosomal protein S8(RPS8)hadnosignificance(P=0.29);while the expression of ND5,ND7,ND9(5th、7th、9th unknowndown-regulated piRNA)and its target gene MT-RNR2 like protein 1(MTRNR2L1)were significantly down-regulated(P<0.01).The above-mentioned piRNA and its target genes had no significant correlation with age,gender,tumor stage,and pathological type of the children(P>0.05).Conclusion: piRNA NU9,NU13,ND5,ND7,ND9 and the target gene MTRNR2L1 are differentially expressed in children with nephroblastoma tissue,which is expected to be a marker to distinguish nephroblastoma from normal kidney tissue.