title: Tumor-suppressive microRNA-206 as a dual inhibitor of MET and EGFR oncogenic signaling in lung squamous cell carcinoma.
abstract: Expression of the oncogene hepatocyte growth factor receptor (MET) and phosphorylation of the MET protein have been associated with both primary and acquired resistance to tyrosine kinase inhibitors (TKIs) used in therapy targeting the epidermal growth factor receptor (EGFR) in patients with non-small cell lung cancers (NSCLCs). Therefore, simultaneous inhibition of both of these receptor tyrosine kinases (RTKs) should improve disease treatment. Our previous study of microRNA (miRNA) expression signatures of lung squamous cell carcinoma (lung-SCC) revealed that microRNA-206 (miR‑206) was significantly reduced in lung-SCC tissues, suggesting that miR‑206 functions as a tumor suppressor in the disease. Furthermore, putative miR‑206 binding sites were annotated in the 3'-UTRs of MET and EGFR RTKs in miRNA databases. The aim of the study was to investigate the functional significance of miR‑206 in lung-SCC and to confirm the inhibition of both MET and EGFR oncogenic signaling by expression of miR‑206 in cancer cells. We found that restoration of mature miR‑206 inhibited cancer cell proliferation, migration, and invasion in EBC-1 cells through downregulation of both mRNA and protein levels of MET and EGFR. Interestingly, phosphorylation of ERK1/2 and AKT signaling were inhibited by restoration of miR‑206 in cancer cells. Overexpression of MET and EGFR were observed in clinical specimens of lung-SCC. Tumor-suppressive miR‑206 inhibited dual signaling networks activated by MET and EGFR, and these findings will provide new insights into the novel molecular mechanisms of lung-SCC oncogenesis and new therapeutic approaches for the treatment of this disease.
authors.affiliation: Department of Pulmonary Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Hiroko
authors.initials: H
authors.lastname: Mataki
authors.affiliation: Department of Functional Genomics, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Naohiko
authors.initials: N
authors.lastname: Seki
authors.affiliation: Department of Urology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Chiyomaru
authors.affiliation: Department of Urology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Enokida
authors.affiliation: Department of Functional Genomics, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Goto
authors.affiliation: Department of Pulmonary Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Kumamoto
authors.affiliation: Department of Pulmonary Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Machida
authors.affiliation: Department of Pulmonary Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Mizuno
authors.affiliation: Department of Urology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Nakagawa
authors.affiliation: Department of Pulmonary Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Hiromasa
authors.initials: H
authors.lastname: Inoue
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017209:Apoptosis / Q000235:genetics; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics; D049109:Cell Proliferation / Q000235:genetics; D066246:ErbB Receptors / Q000235:genetics / Q000378:metabolism*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D008297:Male; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D019859:Proto-Oncogene Proteins c-met / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: C546087:MIRN206 microRNA, human; D035683:MicroRNAs; C512478:EGFR protein, human; D066246:ErbB Receptors; C491743:MET protein, human; D019859:Proto-Oncogene Proteins c-met; D051057:Proto-Oncogene Proteins c-akt