[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: The human paraoxonase (PON) gene family has three isoforms: PON1, PON2 and PON3. These genes are implicated as potential risk factors of cerebrovascular disease and can prevent oxidative modification of low-density lipoproteins and atherosclerosis. This study evaluated the association between the genetic variants of all three PON genes and the risks of total stroke, ischemic stroke and hemorrhagic stroke in the Han Chinese population. METHODS: A total of 1016 subjects were recruited, including 508 healthy controls and 498 patients (328 with ischemic stroke and 170 with hemorrhagic stroke). A total of 11 single nucleotide polymorphisms (SNPs) covering the PON genes were genotyped for statistical analysis. Two of the 11 SNPs (rs662 and rs854560) were contextualized in a meta-analysis of ischemic stroke. RESULTS: The presence of rs705381 (-162) in the promoter region of PON1 was significantly associated with total stroke (Padjusted = 0.0007, OR = 0.57 [95% CI = 0.41-0.79]) and ischemic stroke (Padjusted = 0.0017, OR = 0.54 [95% CI = 0.37-0.79]) when analyzed using a dominant model, but was not associated with hemorrhagic stroke. There was also a nominal association between rs854571 (-824) and total stroke. Meta-analysis demonstrated a significant nominal association between rs662 and ischemic stroke, but there was no evidence of an association between rs662 and ischemic stroke risk in a single site association study. CONCLUSIONS: These findings indicate that polymorphisms of PON1 gene may be a risk factor of stroke.
BMC Medical Genetics 01/2013; 14(1):16. · 2.54 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Low-grade glioma is predisposed to progress to anaplastic astrocytoma and eventually secondary glioblastoma. The malignant transformation may involve the accumulation of multiple genetic alterations. The purpose of this study was to explore the role of miR-544 in glioma progression and discuss whether it may be a novel biomarker of malignant transformation. The expression of miR-544 was measured in a series of 198 glioma samples (63 low-grade glioma, 44 anaplastic astrocytoma and 91 glioblastoma tumors) using microarrays. Quantitative real-time reverse transcription PCR (qRT-PCR) was used to validate the expression levels of miR-544 in tissue and serum samples in an independent validated cohort (25 low-grade glioma, 21 anaplastic astrocytoma and 20 glioblastoma tumors). A Pearson correlation analysis was performed to examine the correlation between miR-544 levels of tissue and serum samples. Microarrays revealed that the expression levels of miR-544 decreased significantly in anaplastic gliomas (P<0.01) or glioblastoma (P<0.01) compared with low-grade gliomas. In an independent cohort of glioma patients, miR-544 exhibited a progression-associated downregulation in glioma tumors. The levels of miR-544 in serum samples tended to be lower in anaplastic and glioblastoma patients compared with low-grade gliomas, but with no significant difference. The Pearson correlation analysis revealed a weakly positive correlation between tissue and serum levels of miR-544. These data support a significant role for miR-544 aberration in the malignant transformation of glioma. The downregulation of miR-544 in tissue may be used as a novel biomarker.
[Show abstract][Hide abstract] ABSTRACT: MicroRNAs (miRNAs) are a class of small non-coding RNAs that regulate gene expression at the posttranscriptional level. The dysregulation of miRNAs has been linked to a series of diseases, including various types of cancer. Since their discovery in the circulation of cancer patients, there has been a steady increase in the study of circulating miRNAs as stable, non-invasive biomarkers. However, the origin and function of circulating miRNAs has not been systematically elucidated. In this review, we summarize the discovery of circulating miRNAs and their potential as biomarkers. We further emphasize their possible origin and function. Finally, we discuss the application and existing questions surrounding circulating miRNAs in cancer diagnostics. Although several challenges remain to be concerned, circulating miRNAs could be useful, non-invasive biomarkers for cancer diagnosis.
Journal of Experimental & Clinical Cancer Research 04/2012; 31:38. · 3.07 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To explore the expression pattern, prognostic value and functional role of miR-196b in glioblastoma (GBM) patients using large cohorts.
MiR-196b expression was measured using the Human v2.0 miRNA Expression BeadChip (Illumina) in 198 frozen glioma tissues. The expression levels of miR-196b were also validated in an independent cohort containing 128 formalin-fixed paraffin-embedded (FFPE) glioma samples using qRT-PCR. The presence of other molecular prognostic indicators was assessed centrally in the glioma samples. Whole genome gene profiling was performed to investigate the underlying biological behavior. MiR-196b functional analyses were performed in U87 and U251 cell lines.
The expression levels of miR-196b were inversely correlated with overall survival in GBM patients. Gene set enrichment analysis (GSEA) showed that the gene sets relating to cell cycle were significantly enriched in the cases with miR-196b overexpression. Functional analyses in U87 and U251 cells revealed that miR-196b was involved in cell proliferation.
MiR-196b is overexpressed and confers a poor prognosis via promoting cellular proliferation in GBM patients.
PLoS ONE 01/2012; 7(6):e38096. · 3.73 Impact Factor