| Institution: | 1.Laboratorio de Investigación Clínica,Unidad Académica de Ciencias Químico Biológicas, Universidad Autónoma de Guerrero,Chilpancingo,México;2.Instituto Nacional de Salud Pública,Cuernavaca,México;3.Laboratorio de Virología y Epigenética del Cáncer,Unidad Académica de Ciencias Químico Biológicas, Universidad Autónoma de Guerrero,Chilpancingo,México;4.Laboratorio de Investigación en Citopatología e Histoquímica,Unidad Académica de Ciencias Químico Biológicas, Universidad Autónoma de Guerrero,Chilpancingo,México;5.Instituto Estatal de Cancerología “Dr. Arturo Beltrán Ortega”,Acapulco de Juárez,México;6.Laboratorio de Biomedicina Molecular, Unidad Académica de Ciencias Químico Biológicas, Universidad Autónoma de Guerrero,Chilpancingo,México |
| Abstract: | BackgroundThe aberrant expression of miR-23b is involved in the development and progression of cancer. The aim of this study was to evaluate the potential role of methylation in the silencing of miR-23b in cervical cancer cell lines and to determine its expression in stages of malignant progression and in cervical cancer tissues HPV16-positive.MethodsThe methylation of the miR-23b promoter was determined in HeLa, SiHa, CaSki and C33A cells using a Human Cancer miRNA EpiTectMethyl II Signature PCR Array®. The cells were treated with 5-Aza-2′-deoxycytidine, and the expression of miR-23b, uPa, c-Met and Zeb1 was determined by qRT-PCR. miR-92a and GAPDH were used as controls. The expression of miR-23b was determined in cervical scrapes and biopsies of women without squamous intraepithelial lesions, with precursor lesions and with cervical cancer, all were HPV16-positive. The Fisher exact and Mann–Whitney tests were used to compare the differences of the expression of miR-23b, uPa, c-Met and Zeb1 among cell groups, and the difference among patients, respectively. The association between the expression of miR-23b and cervical cancer was determined by logistic regression with a confidence level of 95 %. A value of p?<?0.05 was considered statistically significant.ResultsIn C33A, HeLa and CaSki cells, methylation was associated with decreased expression of miR-23b. After treatment with 5-Aza-CdR, the expression of miR-23b increased in all cell lines and the expression of c-Met decreased in HeLa cells, while uPa and Zeb1 decreased in C33A and CaSki cells. In SiHa cells the expression of uPa, c-Met and Zeb1 increased. The expression of miR-23b decreased in relation to the increase in the severity of the lesion and was significantly lower in cervical cancer. In women with premalignant lesions HPV16-positive, decreased levels of miR-23b increased the risk of cervical cancer (OR?=?36, 95 % CI?=?6.7-192.6, p?<?0.05).ConclusionsThe results suggest that the expression of miR-23b is regulated by the methylation of its promoter and is possible that this microRNA influence the expression of uPa, c-Met and Zeb1 in cervical cancer cells lines. In women with premalignant lesions and cervical cancer infected with HPV16, the expression level of miR-23b agree with a tumor suppressor gene. |
