MiR-373 Inhibits the Epithelial-Mesenchymal Transition of Prostatic Cancer via Targeting Runt-Related Transcription Factor 2

MicroRNA‑373‑3p inhibits the proliferation and invasion of non‑small‑cell lung cancer cells by targeting the GAB2/PI3K/AKT pathway

MicroRNAs (miRNAs) were previously demonstrated to be involved in the pathogenesis of non-small-cell lung cancer (NSCLC); however, the roles of certain miRNAs in NSCLC remain to be elucidated. The present study aimed to investigate the functions of screened miRNAs in NSCLC and the potential mechanisms. First, expression profiles of miRNAs were downloaded from the Gene Expression Omnibus (dataset no. GSE29248) and the differentially expressed miRNAs were analyzed by bioinformatics methods. Reverse transcription-quantitative PCR was used to validate the differential expression of miR-373 in clinical samples. The association between miR-373 expression levels and clinicopathological characteristics was also investigated. To further examine how miR-373 mediates the emergence of NSCLC, western blot, Cell Counting Kit-8, cell invasion and wound-healing assays, as well as apoptosis detection and a luciferase assay were used. The results indicated significant downregulation of miR-373 in NSCLC tissues and its low expression was closely associated with the degree of differentiation, clinical stage and tumor size, and was indicative of an unfavorable prognosis for patients with NSCLC. A functional study indicated that overexpression of miR-373 inhibited the proliferation, promoted apoptosis, and suppressed invasion and migration of NSCLC cells. Bioinformatics prediction and functional assays suggested that Grb-associated binding protein 2 (GAB2) was a direct target of miR-373. In addition, GAB2 was found to be significantly upregulated in NSCLC tissues, and clinically, miR-373 was negatively associated with GAB2. Furthermore, overexpression of GAB2 blocked the tumor suppressive effects of miR-373 on NSCLC cells. Mechanistically, miR-373 mimics were able to reduce the expression of GAB2 and subsequently decrease the phosphorylation level of AKT and mTOR protein. The present results indicate that miR-373 exerts its anti-tumor effects in NSCLC cells by targeting the GAB2/PI3K/AKT pathway, suggesting that miR-373 may be a potential therapeutic target in NSCLC.

Niraparib restrains prostate cancer cell proliferation and metastasis and tumor growth in mice by regulating the lncRNA MEG3/miR-181-5p/GATA6 pathway

Background

Poly (ADP-ribose) polymerase (PARP) inhibitors (PARPi), have gained approval for treating patients with castration-resistant prostate cancer (CRPC). Maternally expressed gene 3 (MEG3), a long non-coding RNA (lncRNA), plays a role in inhibiting tumorigenesis through regulating DNA repair genes. This study aimed to investigate the association between the anti-prostate cancer (PCa) effect of niraparib, a representative PARPi, and MEG3 expression, as well as explore the downstream pathway involved.

Methods

The levels of MEG3, miR-181-5p, GATA binding protein 6 (GATA6) in clinical samples from PCa patients were accessed by RT-qPCR. PC3 cells were treated with niraparib, and the expression of MEG3, miR-181-5p, GATA6 expression was tested. PC3 cell proliferation, migration, and invasion were tested by CCK-8, wound healing, and Transwell assays, respectively. The bindings between miR-181-5p and MEG3/GATA6 were determined by dual-luciferase reporter gene assay. Furthermore, rescue experiments were conducted to investigate the underlying mechanism of MEG3/miR-181-5p/GATA6 axis in PCa progression. Additionally, mice were injected with PC3 cells transfected with sh-MEG3 and treated with niraparib, and the xenograft tumor growth was observed.

Results

MEG3 and GATA6 were upregulated and miR-181-5p was downregulated in PCa patients. Niraparib treatment substantially upregulated MEG3 and GATA6, and downregulated miR-181-5p expression in PCa cells. Niraparib effectively restrained PC3 cell proliferation, migration, and invasion. MiR-181-5p targeted to MEG3, and the inhibitory effects of MEG3 overexpression on PC3 cell proliferation and metastasis were abrogated by miR-181-5p overexpression. Moreover, GATA6 was identified as a target of miR-181-5p, and GATA6 silencing abolished the inhibitory effects of miR-181-5p inhibition on PC3 cell proliferation and metastasis. Besides, MEG3 silencing could abrogate niraparib-mediated tumor growth inhibition in mice.

Conclusions

Niraparib restrains prostate cancer cell proliferation and metastasis and tumor growth in mice by regulating the lncRNA MEG3/miR-181-5p/GATA6 pathway.

Retracted: MiR-373 Inhibits the Epithelial-Mesenchymal Transition of Prostatic Cancer via Targeting Runt-Related Transcription Factor 2

[This retracts the article DOI: 10.1155/2021/6974225.].

Long non-‑coding RNA SNHG16 functions as a tumor activator by sponging miR‑373‑3p to regulate the TGF‑β‑R2/SMAD pathway in prostate cancer

Long non‑coding RNAs (lncRNAs) are involved in the pathogenesis of prostate cancer (PCa) as competitive endogenous RNA. The present study aimed to investigate the molecular mech--anisms of lncRNA small nucleolar RNA host gene 16 (SNHG16) in the proliferation and metastasis of PCa cells. Cancer tissues and adjacent normal tissues were collected from 80 patients with PCa who did not receive any treatment. Reverse transcription‑quantitative PCR analysis was performed to detect the expression levels of SNHG16, hsa‑microRNA (miRNA/miR)‑373‑3p and transforming growth factor‑β receptor type 2 (TGF‑β‑R2), and Spearman's correlation coefficient analysis was performed to assess the correlations between these molecules. Furthermore, the effects of SNHG16 knockdown and overexpression on the biological functions of DU‑145 PCa cells and TGF‑β‑R2/SMAD signaling were analyzed. The dual‑luciferase reporter assay was performed to assess the associations between SNHG16 and miR‑373‑3p, and TGF‑β‑R2 and miR‑373‑3p, the effects of which were verified via rescue experiments. The results demonstrated that the expression levels of SNHG16 and TGF‑β‑R2 were significantly upregulated in PCa tissues, whereas miR‑373‑3p expression was significantly downregulated (P<0.001). In addition, negative correlations were observed between SNHG16 and miR‑373‑3p (rho, ‑0.631) and miR‑373‑3p and TGF‑β‑R2 (rho, ‑0.516). Overexpression of SNHG16 significantly promoted the proliferation, migration and invasion of PCa cells (P<0.05), and significantly increased the protein expression levels of TGF‑β‑R2, phosphorylated (p)‑SMAD2, p‑SMAD3, c‑Myc and E2F4 (P<0.001). Notably, the results revealed that miR‑373‑3p is a target of SNHG16, and miR‑373‑3p knockdown rescued short hairpin (sh)‑SNHG16‑suppressed cellular functions by promoting TGF‑β‑R2/SMAD signaling. The results also revealed that miR‑373‑3p targets TGF‑β‑R2. Notably, transfection with miR‑373‑3p inhibitor rescued sh‑TGF‑β‑R2‑suppressed cell proliferation and migration. Taken together, the results of the present study suggest that SNHG16 promotes the proliferation and migration of PCa cells by targeting the miR‑373‑3p/TGF‑β‑R2/SMAD axis.