microRNA expression profiling of nasopharyngeal carcinoma
ABSTRACT Nasopharyngeal carcinoma (NPC) is posing a serious health problem worldwide. The association between its pathogenesis and microRNAs (miRNA) has not been elucidated. In this study, miRNA expression profiling was performed to screen the miRNA expression changes in 8 NPC tissues and 4 normal nasopharyngeal tissues. Thirty-four miRNAs were identified to be differentially expressed; of these, one miRNA (miR-18a) was overexpressed and 33 miRNAs (miR-34b, miR-34c, let-7 family, etc.) were underexpressed in NPC tissues compared to the normal samples. Validation was performed by real-time quantitative PCR for two altered miRNAs (miR-34b and let-7g) and one non-differentially expressed miRNA (miR-30c). Unsupervised hierarchical clustering analysis showed that the aberrant miRNAs were correlated with the clinical stage of NPC patients. In addition to several biological pathways that are well characterised in NPC and which were significantly targeted by the underexpressed miRNAs, two novel pathways, nervous system development and sensory perception of sound, were identified to be strongly associated with NPC development. Furthermore, a c-Myc centered miRNA regulatory network was inferred in NPC. Our study reveals that aberrantly expressed miRNAs play important roles in NPC tumorigenesis and may serve as potential targets for novel therapeutic strategies in the future.
SourceAvailable from: Zhenxiao(Shawn) Huang[Show abstract] [Hide abstract]
ABSTRACT: Abstract MicroRNAs can function as tumor suppressor miRNAs. Bcl-2 is an antiapoptotic gene overexpressed in many tumors, including nasopharyngeal carcinoma (NPC). It is reported that microRNA-15a (miR-15a) and microRNA-16-1 (miR-16-1) could act as bcl-2 inhibitors. To investigate their effects on NPC, the authors used recombinant lentiviral vector to upregulate the expression of miR-15a/16-1 in NPC CNE-2Z cells. The authors divided cells into the control group, transfection group, radiotherapy group, and transfection-radiotherapy group. In this experiment, reverse transcription-quantitative polymerase chain reaction was used to detect the expression of miR-15a/16-1 and bcl-2 mRNA. Cell proliferation was analyzed by MTT assay. Flow cytometry was used to measure cell apoptosis. Radiosensitivity was measured using colony-forming experiment. The protein expression of bcl-2 was measured by western blot, the activation levels of caspase were detected by a spectrophotometric method. After transfection, cell proliferation was inhibited, while the apoptosis rate and radiosensitivity were increased. In addition, the activation of caspase-2 and caspase-3 was aggrandized correspondingly. Although the expression levels of bcl-2 mRNA in each group had no difference, the protein expression of bcl-2 was downregulated. These results suggested that miR-15a/16-1 could inhibit cell proliferation and increase the apoptosis and radiosensitivity of CNE-2 cells, by regulating the bcl-2 gene at post-transcriptional level and by increasing the activation of caspase-2 and caspase-3.Cancer Biotherapy and Radiopharmaceuticals 11/2014; DOI:10.1089/cbr.2013.1596 · 1.38 Impact Factor
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ABSTRACT: Nasopharyngeal carcinoma (NPC), a distinct type of head and neck cancer, is prevalent in Southeast Asia and southern China. Ethnic background and environmental factors contribute to the development of NPC, further complicating its pathogenesis. An increasing body of evidence indicates that microRNAs (miRNAs) play an important role in the development and progression of NPC, in particular, 32 miRNAs are involved in NPC tumorigenesis, progression, and metastasis. The causal involvement of miRNAs in NPC and their possible use as biomarkers have been extensively studied with promising results, demonstrating the diagnostic and therapeutic potential of miRNAs in NPC. In this review, we summarize the role of all the known miRNAs involved in the signaling pathway implicated in NPC.Tumor Biology 11/2014; 36(1). DOI:10.1007/s13277-014-2847-3 · 2.84 Impact Factor
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ABSTRACT: miR-34s serve as potential diagnostic and prognostic biomarkers in human cancers.•miR-34s are frequently down-regulated in NSCLC and glioma with consistent report.•miR-34s are frequently up-regulated in cervical neoplasm with consistent report.•Dysregulation of miR-34s in CRC, GC, HCC and PCa with inconsistent report•CRC, GC, HCC and PCa are frequently inconsistent reported with miR-34s.Gene 01/2015; 554(1). DOI:10.1016/j.gene.2014.10.032 · 2.20 Impact Factor