Its relative expression was significantly decreased, however, miR‑21 was increased in the tumor tissues compared to the normal adjacent tissues in patients with ESCC as determined by quantitative polymerase chain reaction (q‑PCR).
Plasma levels of lncRNA HAND2-AS1 were lower in ESCC patients than in healthy controls, and downregulation of plasma lncRNA HAND2-AS1 distinguished early stage ESCC patients from healthy controls. lncRNA HAND2-AS1 overexpression resulted in downregulation of miRNA-21 in cells of ESCC cell lines and inhibited cell proliferation, migration, and invasion. miRNA-21 overexpression failed to affect lncRNA HAND2-AS1 expression but significantly attenuated the inhibitory effect of lncRNA HAND2-AS1 overexpression on cancer cell proliferation, migration, and invasion.
Association between miR-21 and Th subsets could be correlated with the impairment of anti-tumor immunity and ESCC pathogenesis, which could be potentially used as an important target for immunotherapeutic approaches.
This meta-analysis reports significant prognostic value of miR-21 in predicting worse overall survival (OS) in ESCC, PDAC, and CRC with pooled hazard ratio (HR) of 3.49 (95% CI 2.58-4.71, p-value < 0.01).
Comparing EC-UT with healthy, benign and EC-T groups, and a combined group (3 groups set as 1 negative control), the sensitivity and specificity of miR-21 were 71.0 and 96.9, 74.2 and 87.9, 77.4 and 82.9, and 74.2 and 88.0%, respectively.
The assay showed an excellent detection sensitivity down to 100 fM and specificity towards the analysis of miR-21 in cell lines and tissue samples derived from patients with oesophageal squamous-cell carcinoma (ESCC).
Although it has been demonstrated that microRNA-21 (miR-21) can act as an 'oncogene' in esophageal squamous cell carcinoma, its role in radioresistance remains unexplored.
miR-21 expression was increased significantly in ESCC tissues compared with NMAT. miR-21 down-regulation inhibits cell growth, cell invasion and induces cells to apoptosis.
Accordingly, miR-29c, miR-100, miR-133a, and miR-133b were found to be involved in invasion and metastasis of ESCC, and miR-7 and miR-21 were found to be related to the differentiation of ESCC.
The current results confirmed that exosomal miR-21 expression is up-regulated in serum from patients with ESCC versus serum from patients who have benign diseases without systemic inflammation.
MiR-21 was overexpressed in SCCs, when compared to the adjacent non-tumor tissues (P = 0.0007), and was mainly localized in the cytoplasm of stromal cells adjacent to malignant cells.
MTT, wound healing assay and cell cycle showed that proliferation and migration of ESCC cell line Eca109 cells were increased in miR-21 mimics group, and decreased in anti-miR-21 Oligonucleotide (AMO) group after transfection into Eca109 cells with miR-21 mimics, AMO and scramble sequence, respectively.
Serum miRNA-21 is considered to be a novel biomarker for diagnosing ESCC, and it can also be used as a response marker during chemotherapy for ESCC patients.
Importantly, esophageal miR-31 and miR-21 levels were directly associated with the appearance of ESCC in ZD rats, as compared with their cancer-free Zn-sufficient or Zn-replenished counterparts.
The author concluded that MiR-21 was overexpressed in vitro and ESCC, and promoted the cell proliferation, might target PTEN at post-transcriptional level, and regulated the cancer invasion in Kazakh's ESCC.
(1) In preliminary tests, the plasma level of miR-21 was significantly higher (P=0.0218) and that of miR-375 (P=0.0052) was significantly lower in ESCC patients than controls.