OBJECTIVES: We previously reported low expression of miR-375 in squamous-cell carcinoma (SCC) and high expression in adenocarcinoma (AC) of the lung. miR-375's target genes and its function in non-small-cell lung cancer (NSCLC) have not been elucidated. Therefore, the present study was designed to identify the targets of miR-375 and to characterize its function in NSCLC. MATERIALS AND METHODS: Candidate targets of miR-375 were determined using a prediction database and previous data on differential gene expression between SCC and AC. We evaluated miR-375 and target-gene expression levels in 12 NSCLC cell lines. The effect of miR-375 overexpression and knockdown was evaluated in NSCLC cell lines by transfecting them with an miR-375 precursor or inhibitor. A luciferase-reporter assay was performed to confirm a direct interaction between miR-375 and its target gene. Further, a wound-healing assay was performed to evaluate the effect of miR-375 overexpression on the migration of SK-MES-1 cells. Finally, to assess the clinical relevance, 63 clinical NSCLC samples were analyzed. RESULTS: Claudin-1 (CLDN1) has 4 putative miR-375 target sites in its 3'-untranslated region, and this gene was determined to be a target of miR-375. CLDN1 messenger RNA and protein expression were attenuated by overexpression of miR-375 and increased by knockdown of miR-375 in NSCLC cell lines. In a luciferase-reporter assay, miR-375 overexpression resulted in a 3-fold repression of luciferase activity (P<0.001). Cell migration was promoted by miR-375 overexpression, suggesting a high potential for invasion and metastasis in NSCLC expressing high levels of miR-375. In clinical NSCLC samples, there was a negative correlation between miR-375 and CLDN1 expression (r=-0.35, P=0.005). In addition, high miR-375 expression was correlated with a shorter survival time among the clinical samples (P=0.043). CONCLUSION: CLDN1 is a novel target of miR-375, and high miR-375 expression shortens survival in NSCLC.
OBJECTIVES: We previously reported low expression of miR-375 in squamous-cell carcinoma (SCC) and high expression in adenocarcinoma (AC) of the lung. miR-375's target genes and its function in non-small-cell lung cancer (NSCLC) have not been elucidated. Therefore, the present study was designed to identify the targets of miR-375 and to characterize its function in NSCLC. MATERIALS AND METHODS: Candidate targets of miR-375 were determined using a prediction database and previous data on differential gene expression between SCC and AC. We evaluated miR-375 and target-gene expression levels in 12 NSCLC cell lines. The effect of miR-375 overexpression and knockdown was evaluated in NSCLC cell lines by transfecting them with an miR-375 precursor or inhibitor. A luciferase-reporter assay was performed to confirm a direct interaction between miR-375 and its target gene. Further, a wound-healing assay was performed to evaluate the effect of miR-375 overexpression on the migration of SK-MES-1 cells. Finally, to assess the clinical relevance, 63 clinicalNSCLC samples were analyzed. RESULTS: Claudin-1 (CLDN1) has 4 putative miR-375 target sites in its 3'-untranslated region, and this gene was determined to be a target of miR-375. CLDN1 messenger RNA and protein expression were attenuated by overexpression of miR-375 and increased by knockdown of miR-375 in NSCLC cell lines. In a luciferase-reporter assay, miR-375 overexpression resulted in a 3-fold repression of luciferase activity (P<0.001). Cell migration was promoted by miR-375 overexpression, suggesting a high potential for invasion and metastasis in NSCLC expressing high levels of miR-375. In clinicalNSCLC samples, there was a negative correlation between miR-375 and CLDN1 expression (r=-0.35, P=0.005). In addition, high miR-375 expression was correlated with a shorter survival time among the clinical samples (P=0.043). CONCLUSION: CLDN1 is a novel target of miR-375, and high miR-375 expression shortens survival in NSCLC.
Authors: Erika Larrea; Carla Sole; Lorea Manterola; Ibai Goicoechea; María Armesto; María Arestin; María M Caffarel; Angela M Araujo; María Araiz; Marta Fernandez-Mercado; Charles H Lawrie Journal: Int J Mol Sci Date: 2016-04-27 Impact factor: 5.923
Authors: Sarah E Riad; Dalia S Elhelw; Heba Shawer; Nada El-Ekiaby; Ayman Salah; Abdelrahman Zekri; Gamal Esmat; Asma Amleh; Ahmed I Abdelaziz Journal: Front Genet Date: 2018-03-20 Impact factor: 4.599