MicroRNA-485 inhibits malignant biological behaviour of glioblastoma cells by directly targeting PAK4

MiR-199a/b-3p inhibits colorectal cancer cell proliferation, migration and invasion through targeting PAK4 and BCAR3

Background

Colorectal cancer (CRC) is one of the leading causes of cancer-related death worldwide. P21 activated kinase 4 (PAK4) and Breast cancer anti-estrogen resistance 3 (BCAR3) have been reported to be involved in numerous aspects in tumorous progression. In this study, we propose to screen multi-targeted microRNAs. (miRNAs), which simultaneously inhibit neoplastic evolution through suppressing the transcription of target genes.

Methods

MTT and Colony formation assays measured cell’s viability and proliferation. Scratch wound and Transwell assays detected the ability in migration and invasion for SW116 cells. The multi-targeted microRNAs of PAK4 and BCAR3 were predicted using bioinformatics analysis and verified by conducting dual luciferase reporter assay, western blot and qRT-PCR that could detect the expression levels of miR-199a/b-3p.

Results

The knockdown of PAK4 significantly impeded proliferation and colony formation of SW1116 cells when the knockdown of BCAR3 hindered migration and invasion of SW1116 cells. MiR-199a/b-3p directly targeted the 3'-UTR of PAK4 and BCAR3, further effected proliferation, colony formation, migration, and invasion of SW1116 cells. PAK4 or BCAR3 overexpression could partially reversed inhibitory effects of miR-199a/b-3p.

Conclusions

These results provided a new multi-targeted cite for cancerous suppressant to improve the prognosis of CRC inpatients.

miR-99b-5p, miR-380-3p, and miR-485-3p are novel chemosensitizing miRNAs in high-risk neuroblastoma

Neuroblastoma is a deadly childhood cancer arising in the developing sympathetic nervous system. High-risk patients are currently treated with intensive chemotherapy, which is curative in only 50% of children and leaves some surviving patients with life-long side effects. microRNAs (miRNAs) are critical regulators of neural crest development and are deregulated during neuroblastoma tumorigenesis, making miRNA-based drugs an attractive therapeutic avenue. A functional screen of >1,200 miRNA mimics was conducted in neuroblastoma cell lines to discover miRNAs that sensitized cells to low doses (30% inhibitory concentration [IC30]) of doxorubicin and vincristine chemotherapy used in the treatment of the disease. Three miRNAs, miR-99b-5p, miR-380-3p, and miR-485-3p, had potent chemosensitizing activity with doxorubicin in multiple models of high-risk neuroblastoma. These miRNAs underwent genomic loss in a subset of neuroblastoma patients, and low expression predicted poor survival outcome. In vitro functional assays revealed each of these miRNAs enhanced the anti-proliferative and pro-apoptotic effects of doxorubicin. We used RNA sequencing (RNA-seq) to show that miR-99b-5p represses neuroblastoma dependency genes LIN28B and PHOX2B both in vitro and in patient-derived xenograft (PDX) tumors. Luciferase reporter assays demonstrate that PHOX2B is a direct target of miR-99b-5p. We anticipate that restoring the function of the tumor-suppressive miRNAs discovered here may be a valuable therapeutic strategy for the treatment of neuroblastoma patients.

Deciphering specific miRNAs in brain tumors: a 5-miRNA signature in glioblastoma

MicroRNAs are endogenous non-coding RNAs with a marked impact on the development and progression of brain tumors. However, they commonly share different expression patterns in other types of tumors, thereby exhibiting lack of tissue specificity. Here, an integrative holistic analysis of microarray data is established for deciphering dysregulated miRNAs in glioblastoma, distinguishing them from eight other CNS tumors. The identification of dysregulated miRNAs was performed in a pool of 176 patients, 118 of which diagnosed with glioblastoma. Dysregulated miRNAs commonly expressed in glioblastoma were then discriminated from those co-expressed in other CNS tumors and further characterized. Overall, 21 miRNAs were found to be commonly dysregulated in glioblastoma. Notwithstanding, 16 miRNAs also exhibited a differential expression in at least one other CNS tumor. The remaining 5, specifically, hsa-miR-21-3p, hsa-miR-338-5p, hsa-miR-485-5p, hsa-miR-491-5p and hsa-miR-1290, were solely associated to glioblastoma. This signature is in-depth characterized, with the spotlight on tumor progression, invasion and patient survival. These five endogenous molecules, differentially expressed in glioblastoma, are thus suggested as potential therapeutic targets, modulating several genes involved in major signalling pathways, including MAPK/ERK, calcium, PI3K/AKT, mTOR and Wnt. In summary, these findings lay a foundation for further research on the expression and function of specific patterns of miRNAs expression in glioblastoma, providing reference for potential novel targets.

MiR-193-3p attenuates the vascular remodeling in pulmonary arterial hypertension by targeting PAK4

Pulmonary arterial hypertension (PAH) is a progressive pulmonary vascular disease associated with dysfunction of pulmonary artery endothelial cells and pulmonary artery smooth muscle cells (PASMCs). To explore the potential mechanism of miR-193-3p in pulmonary arterial hypertension, human PASMCs and rats were respectively stimulated by hypoxia and monocrotaline to establish PAH model in vivo and in vitro. The expressions of miR-193-3p and p21-activated protein kinase 4 (PAK4) in the lung samples of PAH patients and paired healthy samples from the healthy subjects in PHA cells and rats were detected by quantitative reverse transcriptase-PCR. Morphological changes in lung tissues were determined using hematoxylin and eosin staining. Right ventricular systolic pressure (RVSP) and ratio of right ventricle to left ventricle plus septum (RV/LV p S) were measured. The binding relationship between miR-193-3p and PAK4 was analyzed by TargetScan and verified by luciferase reporter assay. Cell viability, apoptosis, and migration were detected by 3-(4, 5-Dimethylthiazol-2- yl)-2,5-diphenyltetrazolium bromide (MTT) flow cytometry, and wound-healing assays, respectively. The protein expressions of PAK4, proliferating cell nuclear antigen (PCNA), P21, p-AKT, and AKT in vivo or in vitro were determined by Western blot. In this study, we found that in pulmonary arterial hypertension, miR-193-3p expression was downregulated and PAK4 expression was up-regulated. MiR-193-3p directly targeted PAK4 and negatively regulated its expression. Hypoxia condition promoted cell proliferation, migration, and inhibited apoptosis accompanied with increased expressions of PCNA and p-AKT/AKT and decreased expression of P21 in PASMCs. MiR-193-3p overexpression attenuated the effects of hypoxia on PASMCs via downregulating PAK4. Monocrotaline treatment increased p-AKT/AKT and decreased P21 expression and caused pulmonary vascular remodeling in the model rats. MiR-193-3p overexpression attenuated pulmonary vascular remodeling, decreased p-AKT/AKT, and increased P21 levels via downregulating PAK4 in monocrotaline-induced rats. The results in this study demonstrated that upregulation of miR-193-3p reduced cell proliferation, migration, and apoptosis of PAH in vitro and pulmonary vascular remodeling in PAH in vivo through downregulating PAK4.

miRNA signature in glioblastoma: Potential biomarkers and therapeutic targets

MicroRNAs (miRNAs) are transcripts with sizes of about 22 nucleotides, which are produced through a multistep process in the nucleus and cytoplasm. These transcripts modulate the expression of their target genes through binding with certain target regions, particularly 3' suntranslated regions. They are involved in the pathogenesis of several kinds of cancers, such as glioblastoma. Several miRNAs, including miR-10b, miR-21, miR-17-92-cluster, and miR-93, have been up-regulated in glioblastoma cell lines and clinical samples. On the other hand, expression of miR-7, miR-29b, miR-32, miR-34, miR-181 family members, and a number of other miRNAs have been decreased in this type of cancer. In the current review, we explain the role of miRNAs in the pathogenesis of glioblastoma through providing a summary of studies that reported dysregulation of these epigenetic effectors in this kind of brain cancer.

LINC01224 Exhibits Cancer-Promoting Activity in Epithelial Ovarian Cancer Through microRNA-485-5p-Mediated PAK4 Upregulation

Purpose

Long intergenic non-protein coding RNA 1224 (LINC01224) plays vital roles in the tumorigenesis and progression of hepatocellular carcinoma. Here, we determined LINC01224 expression in epithelial ovarian cancer (EOC) tissues and cells. We also assessed the effects of LINC01224 knockdown on the malignant phenotype of EOC cells both in vitro and in vivo. Furthermore, the detailed molecular mechanisms underlying the oncogenic actions of LINC01224 in EOC cells were elucidated.

Methods

Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect LINC01224 expression in EOC tissues and cells. EOC cells were transfected with small interfering RNAs, and cell proliferation, apoptosis, migration, and invasion were assessed using Cell Counting Kit-8 assay, flow cytometry, cell migration assays, and cell invasion assays, respectively. Using tumor xenografts, the effects of LINC01224 silencing on EOC tumor growth were analyzed in vivo. The mechanism underlying LINC01224 regulation of malignant processes in EOC cells was explored using bioinformatics, RNA immunoprecipitation assay, qRT-PCR, Western blotting, and rescue experiments.

Results

LINC01224 expression was upregulated in EOC tissues and cells. LINC01224 upregulation was correlated to tumor size, the International Federation of Gynecology and Obstetrics stage, and lymph node metastasis. LINC01224 depletion in EOC cells suppressed cell proliferation, migration, and invasion and facilitated cell apoptosis in vitro. LINC01224 downregulation also hindered EOC tumor growth in vivo. Mechanistically, LINC01224 served as a competing endogenous RNA for microRNA-485-5p (miR-485-5p) and consequently increased p21-activated kinase 4 (PAK4) expression in EOC cells. Furthermore, miR-485-5p inhibition or PAK4 upregulation significantly abrogated the effects of LINC01224 depletion in EOC cells.

Conclusion

LINC01224/miR-485-5p/PAK4 formed a competing endogenous RNA network regulating the aggressive behavior of EOC. Therefore, targeting this pathway may be an attractive therapeutic strategy for EOC.

Therapeutically actionable PAK4 is amplified, overexpressed, and involved in bladder cancer progression

Muscle-invasive bladder carcinomas (MIBCs) are aggressive genitourinary malignancies. Metastatic urothelial carcinoma of the bladder is generally incurable by current chemotherapy and leads to early mortality. Recent studies have identified molecular subtypes of MIBCs with different sensitivities to frontline therapy, suggesting tumor heterogeneity. We have performed multi-omic profiling of the kinome in bladder cancer patients with the goal of identify therapeutic targets. Our analyses revealed amplification, overexpression, and elevated kinase activity of P21 (RAC1) activated kinase 4 (PAK4) in a subset of Bladder cancer (BLCA). Using bladder cancer cells, we confirmed the role of PAK4 in BLCA cell proliferation and invasion. Furthermore, we observed that a PAK4 inhibitor was effective in curtailing growth of BLCA cells. Transcriptomic analyses identified elevated expression of another kinase, protein tyrosine kinase 6 (PTK6), upon treatment with a PAK4 inhibitor and RNA interference of PAK4. Treatment with a combination of kinase inhibitors (vandetanib and dasatinib) showed enhanced sensitivity compared with either drug alone. Thus, PAK4 may be therapeutically actionable for a subset of MIBC patients with amplified and/or overexpressed PAK4 in their tumors. Our results also indicate that combined inhibition of PAK4 and PTK6 may overcome resistance to PAK4. These observations warrant clinical investigations with selected BLCA patients.

Linc01234 promotes cell proliferation and metastasis in oral squamous cell carcinoma via miR-433/PAK4 axis

Background

Increasing studies have demonstrated that long non-coding RNAs (lncRNAs) play an important role in tumor progression. However, the potential biological functions and clinical importance of Linc01234 in oral squamous cell carcinoma (OSCC) remain unclear.

Methods

We evaluated the expression profile and prognostic value of Linc01234 in OSCC tissues by RT-qPCR. Then, functional in vitro experiments were performed to investigate the effects of Linc01234 on tumor growth, migration and invasion in OSCC. Mechanistically, RT-qPCR, bioinformatic analysis and dual luciferase reporter assays were performed to identify a competitive endogenous RNA (ceRNA) mechanism involving Linc01234, miR-433-3p and PAK4.

Results

We found that Linc01234 was clearly upregulated in OSCC tissues and cell lines, and its level was positively associated with T stage, lymph node metastasis, differentiation and poor prognosis of patients with OSCC. Our results shown that Linc01234 inhibited cell proliferation and metastatic abilities in CAL27 and SCC25 cells following its knockdown. Mechanistic analysis indicated that Linc01234 may act as a ceRNA (competing endogenous RNA) of miR-433-3p to relieve the repressive effect of miR-433-3p on its target PAK4.

Conclusions

Our results indicated that Linc01234 promotes OSCC progression through the Linc01234/miR-433/PAK4 axis and might be a potential therapeutic target for OSCC.

MiR-485-5p as a potential biomarker and tumor suppressor in human colorectal cancer

Aim: To investigate the role of miR-485-5p in colorectal cancer (CRC). Methodology: The level of miR-485-5p in serum and cell lines were measured by quantitative real-time polymerase chain reaction, and analyzed the diagnostic and prognostic value. Additionally, the biological effect of miR-485-5p on CRC cells was also explored in vitro. Results: The receiver operating characteristic (ROC) curves analysis revealed that miR-485-5p was a diagnostic candidate. Kaplan-Meier analyses demonstrated that patients with low serum miR-485-5p had shorter overall survival. In addition, the result of cox regression model indicated that miR-485-5p was not an independent risk factor for progression. Functional study revealed that overexpression of miR-485-5p could inhibit CRC cell proliferation, invasion and facilitates cell apoptosis. Conclusion: Our study revealed that miR-485-5p was a tumor suppressor and it could serve as a potential prognostic biomarker in CRC.

Long Noncoding RNA SNHG7, a Molecular Sponge for microRNA-485, Promotes the Aggressive Behavior of Cervical Cancer by Regulating PAK4

Purpose

A long noncoding RNA called small nucleolar RNA host gene 7 (SNHG7) is known to be a key regulator of biological processes in multiple human cancer types. In this study, our aims were to determine the expression status of SNHG7 in cervical cancer, to figure out the detailed roles of SNHG7 in cervical cancer cells, and to identify the mechanism underlying the activity of SNHG7 in cervical cancer.

Methods

Reverse-transcription quantitative PCR was performed to measure SNHG7 expression in cervical cancer. A Cell Counting Kit-8 assay, flow-cytometric analysis, cell migration and invasion assays, and a tumor xenograft experiment were conducted to respectively determine the effects of SNHG7 on cervical cancer cell proliferation, apoptosis, migration, and invasion in vitro and tumor growth in vivo.

Results

SNHG7 was found to be markedly upregulated in cervical cancer tissues and cell lines. Higher SNHG7 expression significantly correlated with FIGO stage, lymph node metastasis, the depth of cervical invasion, and shorter overall survival in patients with cervical cancer. Functional experiments indicated that a SNHG7 knockdown attenuated proliferation, migration, and invasiveness and promoted apoptosis of cervical cancer cells in vitro. The SNHG7 knockdown also slowed tumor growth in vivo. Further investigation showed that SNHG7 acts as a competing endogenous RNA for microRNA-485 (miR-485) in cervical cancer cells, and the inhibitory actions of the SNHG7 knockdown on the malignant phenotype were reversed by miR-485 inhibition. P21-activated kinase 4 (PAK4) was identified as a direct target gene of miR-485 in cervical cancer, and PAK4 expression was promoted by SNHG7.

Conclusion

SNHG7 functions as an oncogenic RNA in cervical cancer, competitively binds to miR-485, and thereby upregulates PAK4. This SNHG7–miR-485–PAK4 regulatory network may provide insights into the pathogenesis of cervical cancer, and can help in the identification of novel diagnostic and therapeutic approaches for cervical cancer.

Long non-coding RNA MEG3 promotes cerebral ischemia-reperfusion injury through increasing pyroptosis by targeting miR-485/AIM2 axis

OBJECTIVE

Inflammasome contributes to ischemic brain injury by inducing pyroptosis and inflammation. The aim of this study is to unravel the mechanism of long non-coding RNA (lncRNA) maternally expressed gene 3 (MEG3)-mediated regulation of absent in melanoma 2 (AIM2) inflammasome during cerebral ischemia/reperfusion (I/R).

METHODS

In vivo middle cerebral artery occlusion (MCAO) rat model and in vitro oxygen-glucose deprivation/reperfusion (OGD/R)-treated neurocytes model were generated. TTC, H&E staining and TUNEL were performed to assess the cerebral ischemic injury. LDH and MTT assays were used to detect cell viability and cytotoxicity. qRT-PCR was used to detect the expression levels of MEG3, miR-485 and AIM2. Immunohistochemistry (IHC) and immunofluorescence were conducted to detect the AIM2 expression. ELISA and Western blotting were performed to determine the secretion and protein levels of inflammasome signaling proteins. Dual luciferase reporter assay and Ago2-RIP were used to validate the direct interaction among MEG3, miR-485 and AIM2.

RESULTS

In both MCAO rats and OGD/R-treated neurocytes, MEG3 and AIM2 were significantly up-regulated, whereas miR-485 was down-regulated. MCAO induces pyroptosis and release of IL-1β and IL-18 in ischemia brain. MEG3 acted as a molecular sponge to suppress miR-485, and AIM2 was identified as a direct target of miR-485. Knockdown of MEG3 inhibited OGD/R-induced pyroptosis and inflammation, and lack of MEG3 inhibited caspase1 signaling and decreased the expression of AIM2, ASC, cleaved-caspase1 and GSDMD-N. While overexpression of MEG3 exerted opposite effects.

CONCLUSION

MEG3/miR-485/AIM2 axis contributes to pyroptosis via activating caspase1 signaling during cerebral I/R, suggesting that this axis may be a potent therapeutic target in ischemic stroke.

Low expression or hypermethylation of PLK2 might predict favorable prognosis for patients with glioblastoma multiforme

Background

As the most aggressive brain tumor, patients with glioblastoma multiforme (GBM) have a poor prognosis. Our purpose was to explore prognostic value of Polo-like kinase 2 (PLK2) in GBM, a member of the PLKs family.

Methods

The expression profile of PLK2 in GBM was obtained from The Cancer Genome Atlas database. The PLK2 expression in GBM was tested. Kaplan–Meier curves were generated to assess the association between PLK2 expression and overall survival (OS) in patients with GBM. Furthermore, to assess its prognostic significance in patients with primary GBM, we constructed univariate and multivariate Cox regression models. The association between PLK2 expression and its methylation was then performed. Differentially expressed genes correlated with PLK2 were identified by Pearson test and functional enrichment analysis was performed.

Results

Overall survival results showed that low PLK2 expression had a favorable prognosis of patients with GBM (P-value = 0.0022). Furthermore, PLK2 (HR = 0.449, 95% CI [0.243–0.830], P-value = 0.011) was positively associated with OS by multivariate Cox regression analysis. In cluster 5, DNA methylated PLK2 had the lowest expression, which implied that PLK2 expression might be affected by its DNA methylation status in GBM. PLK2 in CpG island methylation phenotype (G-CIMP) had lower expression than non G-CIMP group (P = 0.0077). Regression analysis showed that PLK2 expression was negatively correlated with its DNA methylation (P = 0.0062, Pearson r = −0.3855). Among all differentially expressed genes of GBM, CYGB (r = 0.5551; P < 0.0001), ISLR2 (r = 0.5126; P < 0.0001), RPP25 (r = 0.5333; P < 0.0001) and SOX2 (r = −0.4838; P < 0.0001) were strongly correlated with PLK2. Functional enrichment analysis results showed that these genes were enriched several biological processes or pathways that were associated with GBM.

Conclusion

Polo-like kinase 2 expression is regulated by DNA methylation in GBM, and its low expression or hypermethylation could be considered to predict a favorable prognosis for patients with GBM.

PAK4, a target of miR-9-5p, promotes cell proliferation and inhibits apoptosis in colorectal cancer

Background

Colorectal cancer (CRC) is a leading cause of cancer-related death worldwide. P21-activated kinase 4 (PAK4) and miR-9-5p have emerged as attractive therapeutic targets in several tumor types, but in CRC, the regulation of their biological function and their target association remain unclear.

Methods

The expression of PAK4 in CRC tissues was determined using quantitative real-time PCR and immunohistochemistry analyses. The targeted regulation between miR-9-5p and PAK4 was predicted and confirmed with bioinformatics analysis and the dual-luciferase reporter assay. Functional experiments, including the MTT assay and flow cytometry, were performed to investigate the impact of PAK4 knockdown and miR-9-5p overexpression on cell proliferation and apoptosis in CRC cells.

Results

We found that the expression of PAK4 was upregulated in CRC tissues. PAK4 knockdown significantly suppressed cell proliferation and promoted apoptosis in cells of the CRC cell lines HCT116 and SW1116. We also found that miR-9-5p directly targeted the 3′-UTR of PAK4 mRNA and negatively regulated its expression. The degree of downregulation of miR-9-5p inversely correlated with PAK4 expression. Intriguingly, enforced expression of miR-9-5p suppressed cell proliferation and promoted apoptosis. This could be partially reversed by PAK4 overexpression.

Conclusion

These results suggest that miR-9-5p targeting of PAK4 could have therapeutic potential for CRC treatment.

microRNA-605 directly targets SOX9 to alleviate the aggressive phenotypes of glioblastoma multiforme cell lines by deactivating the PI3K/Akt pathway

Background

Aberrant microRNA (miRNA) expression has been widely reported to play a crucial role in the progression and development of glioblastoma (GBM). miR-605 has been identified as a tumor-suppressing miRNA in several types of human cancers. Nevertheless, the expression profile and detailed roles of miR-605 in GBM remain unclear and need to be further elucidated.

Materials and methods

RT-qPCR analysis was utilized for the determination of miR-605 expression in GBM tissues and cell lines. In addition, CCK-8 assay, transwell migration and invasion assays, as well as sub-cutaneous xenograft mouse models were utilized to evaluate the effects of miR-605 upregulation in GBM cells. Notably, the potential mechanisms underlying the activity of miR-605 in the malignant phenotypes of GBM were explored.

Results

We observed that expression of miR-605 was reduced in GBM tissues and cell lines. Decreased miR-605 expression exhibited significant correlation with KPS score. The overall survival rate in GBM patients with low miR-605 expression was lower than that of patients with high miR-605 expression. Increased miR-605 expression suppressed the proliferation, migration, and invasion of U251 and T98 cells. In addition, miR-605 upregulation impaired tumor growth in vivo. Furthermore, SRY-Box 9 (SOX9) was identified as a direct target gene of miR-605 in U251 and T98 cells. SOX9 expression was shown to exhibit an inverse correlation with miR-605 expression in GBM tissues. Moreover, silencing of SOX9 expression mimicked the tumor-suppressing roles of miR-605 in U251 and T98 cells, while SOX9 restoration rescued the suppressive effects of miR-605 overexpression in the same. Notably, miR-605 suppressed the PI3K/Akt pathway in GBM in vitro and in vivo.

Conclusion

These results demonstrated that miR-605 acts as a tumor suppressor in the development of GBM by directly targeting SOX9 and inhibiting the activation of the PI3K/Akt pathway, suggesting its potential role as a therapeutic target for GBM.

Identification and characterization of differentially expressed miRNAs in HepG2 cells under normoxic and hypoxic conditions

MicroRNAs (miRNAs) are important post-transcriptional regulators involved in hypoxia conditions; however, their roles in HepG2 cells remain poorly understood. Our previous study showed that hypoxia treatment modulated gene expression accompanied by with HepG2 cell proliferation arrest and increased cell death. To better understand the mechanism of phenotypic changes of HepG2 under hypoxia conditions; we conducted a comparative RNA sequencing to identify differentially expressed miRNAs between hypoxia treatment and control cells. In total, 165 differentially expressed miRNAs were identified, among which the expression of 114 miRNAs were up-regulated and that of 51 miRNAs were down-regulated in hypoxia treated HepG2 cells. Expression profiles of eleven randomly selected miRNAs were validated by qRT-PCR. Furthermore, 19 367 annotated target genes of differentially expressed miRNAs were predicted by bioinformatics tools. The Gene Ontology analysis indicated that the molecular function of target genes was primarily related to binding and catalytic activity, and that the Kyoto Encyclopedia of Genes and Genomes annotation for target genes were further classified into pathways involved in cellular processes, metabolism, organismal systems, genetic information processing, human disease and environmental information processing. Among the environmental information processing, certain pathways associated with cell proliferation and apoptosis, such as the hippo signalling pathway, wnt signalling pathway, MAPK signalling pathway and Jak-STAT signaling pathways, represented potential factors in the response to hypoxia treatment. In conclusion, the expression profiles of miRNA in HepG2 cells were significantly altered under hypoxia conditions; which were closely related to cell proliferation arrest and apoptosis. Our findings expand our understanding of miRNAs function in regulating cell fate under hypoxia conditions.

MicroRNAs (miRNAs) are important post-transcriptional regulators involved in hypoxia conditions; however, their roles in HepG2 cells remain poorly understood.

MicroRNA‑663 inhibits the proliferation and invasion of clear cell renal cell carcinoma cells by directly targeting PAK4

Accumulating evidence has demonstrated that microRNAs (miRNAs) are key gene regulators and are abnormally expressed in clear cell renal cell carcinoma (ccRCC). The dysregulation of miRNAs has been implicated in the initiation and progression of ccRCC. Therefore, identification of ccRCC‑associated miRNAs may facilitate the determination of promising therapeutic targets for anti‑cancer treatment. In the present study, miRNA‑663 (miR‑663) expression was downregulated in ccRCC tissues and cell lines. Functional experiments suggested that restoration of miR‑663 expression inhibited the proliferation and invasion of ccRCC cells. In addition, p21 activated kinase 4 (PAK4) was validated as a direct target of miR‑663 in ccRCC cells. PAK4 was upregulated in ccRCC tissues, and the expression level of PAK4 was inversely correlated with the miR‑663 expression level. PAK4 restoration partially attenuated the suppressive roles of miR‑663 overexpression on the proliferation and invasion of ccRCC cells. The present results provide novel insight into the mechanism underlying the occurrence and development of ccRCC, suggesting that the miR‑663/PAK4 axis may be a novel therapeutic target for treatment of patients with ccRCC.

MicroRNA‑940 promotes cell proliferation and invasion of glioma by directly targeting Kruppel‑like factor 9

MicroRNA‑940 (miR‑940) has been extensively studied in the pathogenesis of numerous types of human cancer; however, the expression pattern, roles and molecular mechanisms underlying the regulatory actions of miR‑940 in glioma remain unknown. The present study aimed to further investigate miR‑940 by studying its expression, roles and mechanisms of action in glioma. Reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) was used to detect miR‑940 expression in glioma tissues and cell lines. The regulatory effects of miR‑940 in glioma cell proliferation and invasion were determined using MTT and cell invasion assays. Bioinformatics analyses was performed to identify the potential target of miR‑940, which was further confirmed by luciferase reporter assay, RT‑qPCR and western blot analysis. In the present study, significantly increased miR‑940 expression levels were observed in glioma tissues and cell lines compared with normal brain tissues and normal human astrocytes, respectively. Decreased miR‑940 expression levels attenuated glioma cell proliferation and invasion in vitro. Kruppel‑like factor 9 (KLF9) was predicted as a potential target of miR‑940. Further assays demonstrated that miR‑940 negatively regulated KLF9 expression in glioma cells by directly targeting the 3'‑untranslated regions of KLF9. Additionally, KLF9 expression was downregulated in glioma tissues and was inversely correlated with miR‑940. Furthermore, KLF9 knockdown was able to rescue the effects of miR‑940 on glioma cell proliferation and invasion. The results of the present study suggest that miR‑940 may function as an oncogene in glioma by targeting KLF9 and may be a considered a therapeutic target for the treatment of gliomas.

NLRP3 in human glioma is correlated with increased WHO grade, and regulates cellular proliferation, apoptosis and metastasis via epithelial-mesenchymal transition and the PTEN/AKT signaling pathway

Glioma is the most prevalent and fatal primary tumor of the central nervous system in adults, while the development of effective therapeutic strategies in clinical practice remain a challenge. Nucleotide-binding domain leucine-rich family pyrin-containing 3 (NLRP3) has been reported to be associated with tumorigenesis and progression; however, its expression and function in human glioma remain unclear. The present study was designed to explore the biological role and potential mechanism of NLRP3 in human glioma. The results demonstrated that overexpression of NLRP3, apoptosis-associated speck-like protein containing a caspase-recruitment domain (ASC), caspase-1 and interleukin (IL)-1β protein in human glioma tissues were significantly correlated with higher World Health Organization grades. The in vitro biological experiments demonstrated that NLRP3 downregulation significantly inhibited the proliferation, migration and invasion, and promoted the apoptosis of SHG44 and A172 glioma cell lines. Furthermore, western blot assays revealed that the downregulation of NLRP3 significantly reduced the expression of ASC, caspase-1 and IL-1β protein. Furthermore, NLRP3 knockdown caused the inhibition of epithelial-mesenchymal transition (EMT), and inhibited the phosphorylation of AKT serine/threonine kinase (AKT) and phosphorylation of phosphatase and tensin homolog (PTEN). Consistently, the upregulation of NLRP3 significantly increased the expression of ASC, caspase-1, IL-1β and phosphorylated-PTEN, promoted proliferation, migration, invasion and EMT, inhibited apoptosis, and activated the AKT signaling pathway. The data of the present study indicate that NLRP3 affects human glioma progression and metastasis through multiple pathways, including EMT and PTEN/AKT signaling pathway regulation, enhanced inflammasome activation, and undefined inflammasome-independent mechanisms. Understanding the biological effects of NLRP3 in human glioma and the underlying mechanisms may offer novel insights for the development of glioma clinical therapeutic strategies.

MicroRNA‑485 targets MACC1 and inhibits cervical cancer cell proliferation and invasion

A large body of evidence has indicated that microRNAs (miRNAs/miRs) have essential roles in the development and progression of cervical cancer. Thus, miRNAs with dysregulated expression are potential biomarkers for cervical cancer diagnosis and prognosis. In the present study, expression levels of miR‑485 were detected in cervical cancer tissues and cell lines. The effects of miR‑485 overexpression on the proliferation and invasion of cervical cancer cells were determined with Cell Counting kit‑8 and Transwell invasion assays. The mechanisms underlying the action of miR‑485 in cervical cancer were investigated using bioinformatics analysis, a luciferase reporter assay, reverse transcription‑quantitative polymerase chain reaction and western blot analysis. In addition, the association between miR‑485 and metastasis associated in colon cancer‑1 (MACC1) in cervical cancer tissues was examined. The present study demonstrated that miR‑485 expression was significantly downregulated in cervical cancer tissues and cell lines. Reduced miR‑485 expression in patients with cervical cancer was correlated with International Federation of Gynecology and Obstetrics stage and lymph node metastasis. Furthermore, restored expression of miR‑485 significantly reduced cervical cancer cell proliferation and invasion. MACC1 was identified as a direct target gene of miR‑485 in cervical cancer. MACC1 expression was significantly upregulated in cervical cancer specimens and was inversely correlated with miR‑485 expression. Additionally, the restored expression of MACC1 eliminated the suppressive effects of miR‑485 overexpression on the proliferation and invasion of cervical cancer cells. Notably, the upregulation of miR‑485 suppressed the MET proto‑oncogene, receptor tyrosine kinase (Met)/RAC‑α serine/threonine‑protein kinase (AKT) signaling pathway. These results demonstrated that miR‑485 may perform its tumor suppressive function in cervical cancer by directly targeting MACC1 and inhibiting the Met/AKT signaling pathway. Therefore, the miR‑485/MACC1 axis may be a novel and effective therapeutic target in cervical cancer.

MicroRNA-598 Inhibits Cell Proliferation and Invasion of Glioblastoma by Directly Targeting Metastasis Associated in Colon Cancer-1 (MACC1)

The dysregulation of microRNA (miRNA) expression is closely related with tumorigenesis and tumor development in glioblastoma (GBM). In this study, we found that miRNA-598 (miR-598) expression was significantly downregulated in GBM tissues and cell lines. Restoring miR-598 expression inhibited cell proliferation and invasion in GBM. Moreover, we validated that metastasis associated in colon cancer-1 (MACC1) is a novel target of miR-598 in GBM. Restoring MACC1 expression reversed the inhibitory effects of miR-598 overexpression on GBM cells. In addition, miR-598 overexpression suppressed Met/AKT pathway activation in GBM. Our results provided compelling evidence that miR-598 serves tumor-suppressive roles in GBM and that its antioncogenic effects are mediated chiefly through the direct suppression of MACC1 expression and regulation of the Met/AKT signaling pathway. Therefore, miR-598 is a potential target in the treatment of GBM.