Abstract
Family of forkhead box transcription factors, including forkhead box P4 (FOXP4), plays an important role in oncogenesis. The current study is to evaluate the role of FOXP4 in regulating human non-small cell lung cancer (NSCLC). Quantitative RT-PCR and Western blot were performed to evaluate the gene and protein expressions of FOXP4 in six NSCLC cell lines and 55 NSCLC patients. Lentivirus of small hairpin RNA (FOXP4-shRNA) was used to downregulate FOXP4 in NSCLC cell lines A549 and H1703 cells. Its effect on NSCLC growth, invasion, and cell cycle were evaluated by cell proliferation assay, migration assay, and cell cycle assay, respectively. Dual luciferase assay and Western blot were used to examine whether microRNA-138 (miR-138) was an upstream regulator of FOXP4. The dependence of FOXP4 on miR-138 associated signaling pathway was evaluated by ectopically overexpressing enhancer of zeste homolog 2 (EZH2), a known miR-138 target in NSCLC. FOXP4 was highly expressed in both NSCLC cell lines and NSCLC patients. FOXP4 downregulation by FOXP4-shRNA markedly reduced cancer cell growth and invasion, as well as induced cell cycle arrest in A549 and H1703 cells. MiR-138 was confirmed to be an upstream regulator of FOXP4 and directly regulated FOXP4 expression in A549 and H1703 cells. FOXP4 downregulation-mediated inhibition on cancer cell growth and invasion was independent on overexpressing EZH2, another direct target of miR-138 in NSCLC. Our data demonstrated that FOXP4 was a critical regulator in NSCLC and independently associated with miR-138 regulation.
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References
Group NM-aC. Preoperative chemotherapy for non-small-cell lung cancer: a systematic review and meta-analysis of individual participant data. Lancet. 2014;383:1561–71.
Vivanco I. Targeting molecular addictions in cancer. Br J Cancer. 2014;111:2033–8.
Barr Kumarakulasinghe N, Zanwijk NV, Soo RA. Molecular targeted therapy in the treatment of advanced stage non-small cell lung cancer (NSCLC). Respirology. 2015;20(3):370–8.
Umemura S, Tsuchihara K, Goto K. Genomic profiling of small-cell lung cancer: the era of targeted therapies. Jpn J Clin Oncol. 2015. [Epub ahead of print]
Myatt SS, Lam EW. The emerging roles of forkhead box (Fox) proteins in cancer. Nat Rev Cancer. 2007;7:847–59.
Katoh M, Katoh M. Human FOX gene family (review). Int J Oncol. 2004;25:1495–500.
Feng J, Zhang X, Zhu H, Wang X, Ni S, Huang J. High expression of FoxP1 is associated with improved survival in patients with non-small cell lung cancer. Am J Clin Pathol. 2012;138:230–5.
Shimizu K, Kato A, Hinotsume D, Shigemura M, Hanaoka M, Shimoichi Y, et al. Reduced expressions of Foxp1 and Rassf1a genes in lung adenocarcinomas induced by N-nitrosobis (2-hydroxypropyl) amine in rats. Cancer Lett. 2006;236:186–90.
Dimitrakopoulos F-ID, Papadaki H, Antonacopoulou AG, Kottorou A, Gotsis AD, Scopa C, et al. Association of FOXP3 expression with non-small cell lung cancer. Anticancer Res. 2011;31:1677–83.
Ishibashi Y, Tanaka S, Tajima K, Yoshida T, Kuwano H. Expression of Foxp3 in non-small cell lung cancer patients is significantly higher in tumor tissues than in normal tissues, especially in tumors smaller than 30 mm. Oncol Rep. 2006;15:1315–9.
Pillai RS. MicroRNA function: multiple mechanisms for a tiny RNA? RNA. 2005;11:1753–61.
Calin GA, Croce CM. MicroRNA-cancer connection: the beginning of a new tale. Cancer Res. 2006;66:7390–4.
Nana-Sinkam SP, Geraci MW. MicroRNA in lung cancer. J Thorac Oncol. 2006;1:929–31.
Zhang H, Zhang H, Zhao M, Lv Z, Zhang X, Qin X, et al. MiR-138 inhibits tumor growth through repression of EZH2 in non-small cell lung cancer. Cell Physiol Biochem. 2013;31:56–65.
Teufel A, Wong EA, Mukhopadhyay M, Malik N, Westphal H. FoxP4, a novel forkhead transcription factor. Biochim Biophys Acta. 2003;1627:147–52.
Wang G, Sun Y, He Y, Ji C, Hu B, Sun Y. MicroRNA-338-3p inhibits cell proliferation in hepatocellular carcinoma by target forkhead box P4 (FOXP4). Int J Clin Exp Pathol. 2015;8:337–44.
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Yang, T., Li, H., Thakur, A. et al. FOXP4 modulates tumor growth and independently associates with miR-138 in non-small cell lung cancer cells. Tumor Biol. 36, 8185–8191 (2015). https://doi.org/10.1007/s13277-015-3498-8
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DOI: https://doi.org/10.1007/s13277-015-3498-8