RESUMEN
Idiopathic scoliosis is the most common pediatric spinal deformity affecting 1% to 3% of the population, and adolescent idiopathic scoliosis (AIS) accounts for approximately 80% of these cases; however, the etiology and pathogenesis of AIS are still uncertain. The current study aims to identify the relationship between G protein-coupled receptor 126 (GPR126) gene and AIS predisposition, to identify the relationship between the genotypes of the GPR126 SNPs and the clinical phenotypes of AIS. We conducted a case-control study and genotyped twenty SNPs of GPR126 gene including ten exonic SNPs and ten intronic polymorphisms in 352 Chinese sporadic AIS patients and 149 healthy controls. We provided evidence for strong association of three intronic SNPs of the GPR126 gene with AIS susceptibility: rs6570507 A > G (p =0 .0035, OR = 1.729), rs7774095 A > C (p = 0.0078, OR = 1.687), and rs7755109 A > G (p = 0.0078, OR = 1.687). However, we did not identify any significant association between ten exonic SNPs of GPR126 and AIS. Linkage disequilibrium analysis indicated that rs7774095 A > C and rs7755109 A > G could be parsed into one block. The association between the intronic haplotype and AIS was further confirmed in an independent population with 110 AIS individuals and 130 healthy controls (p = 0.046, OR = 1.680). Furthermore, molecular mechanisms underlying intronic SNP regulation of GPR126 gene were studied. Although intronic SNPs associated with AIS didn't influence GPR126 mRNA alternative splicing, there was a strong association of rs7755109 A > G with decreased GPR126 mRNA level and protein levels. Our findings indicate that genetic variants of GPR126 gene are associated with AIS susceptibility in Chinese populations. The genetic association of GPR126 gene and AIS might provide valuable insights into the pathogenesis of adolescent idiopathic scoliosis.
Asunto(s)
Pueblo Asiatico/genética , Polimorfismo de Nucleótido Simple , Receptores Acoplados a Proteínas G/genética , Escoliosis/genética , Adolescente , Niño , Exones , Femenino , Estudios de Asociación Genética/métodos , Predisposición Genética a la Enfermedad , Humanos , Intrones , Desequilibrio de Ligamiento , Masculino , Receptores Acoplados a Proteínas G/metabolismoRESUMEN
The physiological role of microRNAs (miRNAs) in osteoblast differentiation remains elusive. Exosomal miRNAs isolated from human bone marrow-derived mesenchymal stem cells (BMSCs) culture were profiled using miRNA arrays containing probes for 894 human matured miRNAs. Seventy-nine miRNAs (â¼8.84%) could be detected in exosomes isolated from BMSC culture supernatants when normalized to endogenous control genes RNU44. Among them, nine exosomal miRNAs were up regulated and 4 miRNAs were under regulated significantly (Relative fold>2, p<0.05) when compared with the values at 0 day with maximum changes at 1 to 7 days. Five miRNAs (miR-199b, miR-218, miR-148a, miR-135b, and miR-221) were further validated and differentially expressed in the individual exosomal samples from hBMSCs cultured at different time points. Bioinformatic analysis by DIANA-mirPath demonstrated that RNA degradation, mRNA surveillance pathway, Wnt signaling pathway, RNA transport were the most prominent pathways enriched in quantiles with differential exosomal miRNA patterns related to osteogenic differentiation. These data demonstrated exosomal miRNA is a regulator of osteoblast differentiation.
Asunto(s)
Diferenciación Celular/genética , Exosomas/genética , Células Madre Mesenquimatosas/citología , MicroARNs/genética , Osteogénesis/genética , Transcriptoma , Adulto , Proteína Morfogenética Ósea 2/genética , Femenino , Humanos , Masculino , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reproducibilidad de los ResultadosRESUMEN
BACKGROUND: MicroRNAs (miRNAs) are a class of small non-coding RNAs regulating gene expression that play roles in the pathogenesis of human diseases, including malignancy. miR-21, a commonly overexpressed miRNA in very diverse types of malignancies, may affect tumor progression through targeting tumor suppressor genes. We identified the role of miR-21 in non-small cell lung cancer (NSCLC) and to clarify the regulation of PTEN by miR-21 and determine mechanisms of this regulation. METHODS: Expression of miR-21 and PTEN in 20 paired NSCLC and adjacent non-tumor lung tissues was investigated by qRT-PCR and western blot, respectively. The effect of miR-21 on PTEN expression was assessed in NSCLC cell lines with miR-21 inhibitor to decrease miR-21 expression. Furthermore, the roles of miR-21 in cell growth and invasion were analyzed with miR-21 inhibitor-transfected cells. RESULTS: miR-21 was overexpressed in tumor tissues relative to adjacent non-tumor tissues. Notably, patients with advanced clinical TNM stage (n=16) or distal metastasis (n=5) demonstrated higher miR-21 expression than those without them (n=26, or n=37) (p<0.05, or p<0.001). Tumor tissues showed an inverse correlation between miR-21 and PTEN protein. miR-21 inhibitor transfection increased a luciferase-reporter activity containing the PTEN-3'-UTR construct and increased PTEN protein but not PTEN-mRNA levels in NSCLC cell lines. Finally, miR-21 inhibitor-transfected cells exhibited markedly reduced cell growth and invasive characteristics. CONCLUSIONS: miR-21 post-transcriptionally down-regulates the expression of tumor suppressor PTEN and stimulates growth and invasion in NSCLC. It may be a potential therapeutic target for NSCLC.
