[MiR-9 regulates the expression of CBX7 in human glioma].

OBJECTIVE: To detect the expression of CBX7 in human glioma and investigate the potential regulatory effect of abnormally expressed microRNAs on CBX7 expression. METHODS: Semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blot were applied to detect the expression pattern of CBX7 in 2 human normal brain tissues, 9 glioma tissues, and 3 glioma cell lines. Miranda algorithm and Ensemble Machine Learning algorithm were combined to predict miRNAs that target human CBX7. The expression of miR-9 in those tissues and cell lines were detected by real-time PCR. After miR-9 overexpression in 293ET and miR-9 knock-down in T98G, luciferase assay and Western blot were used to confirm the effect of miR-9 on CBX7 expression. MTT assay and flow cytometry were applied to detect the effect of miR-9 knock-down on T98G cells. RESULTS: No obvious difference in the CBX7 mRNA level between normal and tumor tissues was observed, while the protein level of CBX7 was abrogated or markedly reduced in glioma tissues and cell lines. Several miRNAs including miR-9 may target CBX7 by bioinformatics prediction. MiR-9 was up-regulated in glioma tissues and cell lines. In 293ET cell, luciferase activity of CBX7-3'UTR reporter was decreased to 24% after miR-9 overexpression. After miR-9 knock-down in T98G cell, the luciferase activity was increased by 1.8 fold and there was no change of CBX7 mRNA, while the protein level of endogenous CBX7 was significantly increased. The number of survival T98G cells increased and cells in G1 phase decreased after miR-9 knock-down. CONCLUSION: In human glioma, CBX7 is down-regulated by the inhibition of miR-9 at posttranscriptional level.

MiRE: a graphical R package for microRNA-related analysis.

OBJECTIVE: To provide a set of useful analysis tools for the researchers to explore the microRNA data. METHODS: The R language was used for generating the Graphical Users Interface and implementing most functions. Some Practical Extraction and Report Language (Perl) scripts were used for parsing source files. RESULTS: We developed a graphical R package named miRE, which was designated for the analysis of microRNA functions, genomic organization, etc. This package provided effective and convenient tools for molecular biologists to deal with routine analyses in microRNA-related research. With its help, the users would be able to build a desktop-centered microRNA research environment quite easily and effectively. miRE is freely available at http://www. biosino.org/-kanghu/WorkPresentation/miRE/miRE.html. A detailed user manual and tutorials with example code and image are also available. CONCLUSION: miRE is a tool providing an open-source, user-friendly, integrated interface for microRNA-related analysis. With its help, researchers can perform microRNA-related analysis more efficiently.

[Studies of TGF-beta/Smads expression in lung cancer].

Smad proteins transduce signals from transforming growth factor beta superfamily ligands that regulate cell proliferation, differentiation and death through activation of receptor serine/threonine kinases. TGF-beta/Smads signal pathway not only has transforming potential but can also drive tumourigenesis, malignant progression, invasion and metastasis of human cancers. Using the immuno-histochemistry, we investigate the expression and location of TGF-beta R II, Smad2, Smad4 and Smad7 in 20 lung cancer specimens and 8 lung cancer cell lines. The results suggest that aberrant smads protein expression is significantly related to lung cancer tumoruigenesis and progression. Interestingly, TGF-beta R II and Smad7 strongly express in high metastasis cell lines. High expression of TGF-beta R II and smad7 in the cell lines with high-metastatic potential showed a conceivable TGF-beta signal pathway independent Smads in the lung cancer, and that might mediate invasion and metastasis of lung cancer.