Characterization and effects of miR-21 expression in esophageal cancer

Abstract

ABSTRACT. The aim of this study was to investigate the expression of miR-21 in esophageal cancer and the impact of miR-21 on apoptosis, invasion, and the expression of target genes in esophageal cancer cells. Fluorescence quantitative polymerase chain reaction analysis was used to detect the expression of miR-21 in human esophageal tissues, adjacent tissues, and an esophageal cancer cell line (TE-13). The antisense miR-21 oligonucleotide was generated commercially using the solidphase chemical synthesis method. Transient transfection was used to transfect esophageal cancer cells (TE-13 antisense and TE-13 control cells). Flow cytometry and Transwell cell assays were used to detect the apoptosis and invasion of esophageal cancer cells, respectively. The western blot method was used to detect the expression of PTEN, PDCD4, and K-ras proteins. These analyses determined that mir-21 expression significantly increased in esophageal cancer tissues and in TE-13 cells, and that this phenomenon was not associated with staging or lymph node metastasis. The apoptosis rate of TE-13 control cells was lower than that of antisense TE-13 cells indicating an enhanced 8811 miR-21 in esophageal cancer ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 14 (3): 8810-8818 (2015) invasive ability. In tissues adjacent to esophageal cancer and in TE-13 antisense cells, the expression of PTEN and PDCD4 was found to be higher than that in the control group, whereas the expression of K-ras showed the opposite pattern. Together, these results suggest that miR-21 might be involved in the development and metastasis of esophageal cancer, through interaction with its PDCD4 and K-ras target genes.

Identification of molecular targets for esophageal carcinoma diagnosis using miRNA-seq and RNA-seq data from The Cancer Genome Atlas: a study of 187 cases

“…The up-regulation of miR-21 can predict an unfavorable prognosis in ESCA, as confirmed by three independent meta-analyses [30–32]. Several studies also found that the up-regulation of miRNA-21 could serve as a potential diagnostic biomarker [33–36], which is consistent with our result using TCGA data.…”

Research progress on the relationship between zinc deficiency, related microRNAs, and esophageal carcinoma

“…MiR‐21 expression in EC tissues in patients with lymph node metastasis was significantly higher than in patients without lymph node metastasis. The results also showed that high miR‐21 expression in TE‐13 cells increased cell proliferation and invasion and inhibited apoptosis …”

“…The results also showed that high miR-21 expression in TE-13 cells increased cell proliferation and invasion and inhibited apoptosis. 22 Komatsu et al conducted in vivo testing to ascertain whether oncogenic miR-21 promoted chemoresistance in EC patients and acted as a biomarker for predicting chemoresistance in plasma from patients with EC. All EC patients were treated with a preoperative chemotherapy regimen of cisplatin plus 5-fluorouracil (5-FU).…”

miR-124 radiosensitizes human esophageal cancer cell TE-1 by targeting CDK4

“…Of these, miR-124 has been reported to be important in a variety of cancers (Cao et al, 2007;Visvanathan et al, 2007). Wen et al (2015) reported that miR-21 might be involved in the development and metastasis of esophageal cancer through its interaction with target genes programmed cell death 4 (PDCD4) and K-ras. Deng et al (2013) showed that overexpression of CDK4 results in a poorer prognosis and confers resistance of glioma cells to radiation.…”