Aberrant microRNA (miR) expression is implicated in multiple human malignancies. miR-21, acting as a proto-oncogene, is involved in a variety of cellular processes and tumorigenesis and is frequently overexpressed in some cancer types.
Subsequently, pacritinib treatment suppressed GBM tumorigenesis and stemness; more importantly, pacritinib-treated GBM cells showed a markedly reduced ability to secret M2 cytokines and reduced miR-21-enriched exosomes secreted by GAMs.
Accumulating evidence has suggested that microRNAs play important roles in the development of hepatocellular carcinoma (HCC) and are involved in drug resistance. miR-21-5p was overexpressed in a variety of cancers and promoted the tumorigenesis; however, the function of miR-21-5p in HCC still remains unknown.
Data herein provided identified for the first time new mechanisms supporting the crucial role of cigarette smoke-induced miR-21 expression in the amplification of inflammatory responses and in tumorigenesis processes within the airways.
However, it remains unclear whether there is any functional link between DSBs and miR-21 expression and, if so, does the link contribute to DSB-induced genomic instability/tumorigenesis.
MiR-21-5p activation by HCV is a key molecular step, promoting both HCV life cycle and HCV-3a core-induced steatosis and may be among the molecular changes induced by HCV-3a to promote carcinogenesis.
Considering the target genes identified for miR-21 in HNSCC, this transcript is an important player in several cellular processes that control carcinogenesis.
Although miR-21-5p upregulation has been demonstrated to associate with tumorigenesis by controlling the expression of oncogenic and tumor suppressor genes, only a small number of studies have investigated the expression of miR-21-5p and its functional role in CC.
In lung specimens (tumor and non-tumor), microRNAs known to be involved in lung tumorigenesis (miR-21, miR-200b, miR-126, miR-451, miR-210, miR-let7c, miR-30a-30p, miR-155 and miR-let7a, qRT-PCR), DNA methylation, and downstream biomarkers were determined (qRT-PCR and immunoblotting) in 40 patients with LC (prospective study, subdivided into LC-COPD and LC, <i>N</i> = 20/group).
Arsenic is a metalloid environmental carcinogen involved in the occurrence and development of many cancers. miRNA-21 plays a crucial role in arsenic-induced carcinogenesis.
Aberrant microRNA (miRNA/miR) expression has been reported in various cancer types. miR‑21, which is considered to be a proto-oncogene and is frequently overexpressed in certain cancer types, has been implicated in tumorigenesis.
The ceRNA network analysis revealed that the differentially regulated miR-21 and miR-148a were playing as central candidates coordinating sponging activity of the lncRNAs analyzed (H19, TUG1 and MALAT1) in this study and the overexpression of H19 and miR-21 could be a signature event of gastric tumorigenesis that could serve as prognostic indicators and therapeutic targets.
As miR-21 was involved in tumorigenesis and osteoclastogenesis, we further proved the existence of miR-21 in A549 cell-derived exosomes and investigated its function.
MicroRNA-21 (miR-21) has been demonstrated to play an important role in carcinogenesis; however, its mechanism of action in colorectal cancer (CRC) has not been fully elucidated.
We conclude that miR-21 promotes mTORC1-driven tumorigenesis <i>via</i> a mechanism that involves the mitochondria, and that miR-21 is a potential therapeutic target for TSC-associated hamartomas and other mTORC1-driven tumors, with the potential for synergistic efficacy when combined with rapalogs.
Taken together, these data suggest the key functions of miR-21 in mediating anti-tumor immune response and thereby uncover a bi-directional role of this traditionally known 'oncomiR' in tumorigenesis.