Recent studies showed that miR-145 silenced c-Myc and its downstream targets in colon cancer, which be associated with c-Myc/eIF4E as a miR-145 target [19]. Interestingly, downregulation of the miR-145 in NSCLC is consistent with upregulation of c-Myc, eIF4E and CDK4 in the same sample set which is consistent with our finding that c-Myc is a major target for miR-145 by ChIP. Knock down of c-Myc, eIF4E and CDK4 respectively showed that they are all important for proliferation in both cell

lines. Furthermore, by silencing eIF4 and CDK4 we confimed learn more CDK4 is crucial in the progression of cell cycle. Based on our findings, we propose that miR-145 regulates NSCLC cell proliferation partly by targeting c-Myc, and that the loss of miR-145 may provide a selective growth advantage during lung

carcinogenesis. In summary, we conducted miR-145 expression profiling in human NSCLC cells, and focused on the identification of targets of abnormally expressed miR-145. Our results showed that miR-145 was significantly downregulated and might be used as a marker MX69 in vivo for advanced NSCLC. In addition, we also found that miR-145 targeted c-Myc, which suggested an explanation for the carcinogenesis pathway mediated by miR-145 and provided data that may contribute to molecular targeted therapy based on miRNAs. Acknowledgements We thank Shanghai Sensichip Company for its wonderful technical support. This work is sponsored by Shanghai Pujiang Program. References 1. Jemal A, Siegel R, Ward E, Hao Y, Xu J, Thun MJ: Cancer statistics, 2009. CA Cancer J Clin 2009, 59: 225–49.PubMedCrossRef 2. Spira A, Ettinger DS: Multidisciplinary management of lung cancer. N Engl

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