Tumor-suppressive effects of microRNA-181d-5p on non-small-cell lung cancer through the CDKN3-mediated Akt signaling pathway in vivo and in vitro

Abstract

The involvement of several microRNAs (miRs) in the initiation and development of tumors through the suppression of the target gene expression has been highlighted. The aberrant expression of miR-181d-5p and cyclin-dependent kinase inhibitor 3 (CDKN3) in non-small-cell lung cancer (NSCLC) was then screened by microarray analysis. In the present study, we performed a series of in vivo and in vitro experiments for the purpose of investigating their roles in NSCLC and the underlying mechanism. There was a high expression of CDKN3, whereas miR-181d-5p was downregulated in NSCLC. Quantitative RT-PCR, Western blot analysis, and dual-luciferase reporter gene assay further identified that CDKN3 could be negatively regulated by miR-181d-5p. Moreover, the upregulation of miR-181d-5p or silencing of CDKN3 could inactivate the Akt signaling pathway. A549 with the lowest miR-181d-5p and H1975 with the highest CDKN3 among the five NSCLC cell lines (H1299, A549, H1975, NCI-H157, and GLC-82) were adopted for in vitro experiments, in which expression of miR-181d-5p and CDKN3 was altered by transfection of miR-181d-5p mimic/inhibitor or siRNA-targeting CDKN3. Afterwards, cell proliferation, apoptosis, invasion, migration, and angiogenesis, as well as epithelial-mesenchymal transition (EMT), were evaluated, and tumorigenicity was assessed. In addition, an elevation in miR-181d-5p or depletion in CDKN3 led to significant reductions in proliferation, invasion, migration, angiogenesis, EMT, and tumorigenicity of NSCLC cells, coupling with increased cell apoptosis. In conclusion, this study highlights the tumor-suppressive effects of miR-181d-5p on NSCLC via Akt signaling pathway inactivation by suppressing CDKN3, thus providing a promising therapeutic strategy for the treatment of NSCLC.

Long non-coding RNA NEAT1 inhibits oxidative stress-induced vascular endothelial cell injury by activating the miR-181d-5p/CDKN3 axis

“…Gao et al demonstrated that miR-181d-5p inhibited nonsmall-cell lung cancer progression via the CDKN3/Akt pathway [25]. Therefore, we demonstrated the relationship between NEAT1, miR-181d-5p and CDKN3 in HUVECs.…”

“…It has been indicated that miR-181d-5p is a suppressor of multiple cell processes [25]. We found that AS mouse serum and t-BHP-treated HUVECs showed lower levels of miR-181d-5p.…”

“…The NEAT1/miR-181d-5p axis regulates CDKN3 expression in HUVECs miR-181d-5p inhibited non-small-cell lung cancer progression by targeting CDKN3A [25]. Hence, we hypothesized that CDKN3 is a direct target of miR-181d-5p in HUVECs.…”

miR-181d/RBP2/NF-κB p65 Feedback Loop Promotes Chronic Myeloid Leukemia Blast Crisis

“…Following this, we determined that miR-181d overexpression signi cantly promoted leukemia cell proliferation, and its greatly suppressed cell proliferation. The possible mechanism by which miR-181d regulates cell proliferation was reported to be associated with the regulation of KNAIN2, CDKN3 and CYLD [26][27][28]. In this study, we revealed a new mechanism and showed that miR-181d promotes leukemia cell proliferation by directly targeting and negatively regulating the histone demethylase RBP2.…”

miR-181d/RBP2/NF-κB p65 Feedback Regulation Promotes Chronic Myeloid Leukemia Blast Crisis

“…The possible mechanism by which miR-181d regulates cell proliferation was reported to be associated with the regulation of NKAIN2, CDKN3 and CYLD (28)(29)(30). As the targets of miR-181d, NKAIN2 knockdown could reverse the inhibition of miR-181d downregulation on pancreatic cancer development (28), CDKN3 mediated the pathogenesis of nonsmall-cell lung cancer (NSCLC) (29), while CYLD regulated invasion-mediated epithelial-mesenchymal transition (EMT), which resulted in gastric cancer (30). Besides, CYLD acted as a crucial regulator of Adult T-cell leukemia/lymphoma (ATLL) survival (31).…”