MicroRNA-936 targets FGF2 to inhibit epithelial ovarian cancer aggressiveness by deactivating the PI3K/Akt pathway

CircZCCHC2 (hsa_circ_0000854) promotes hepatocellular carcinoma progression through modulating miR-936/BTBD7 axis and activating Rho/ROCK2 pathway

Hepatocellular carcinoma (HCC) is one of the most aggressive and refractory cancers due to its high propensity to metastasize and the unavailability of efficacious treatments. Circular RNAs (circRNAs) participate in diverse biological activities in human cancers. Here, we detected the upregulation of a novel circRNA, circZCCHC2 (hsa_circ_0000854), in HCC samples and cells. The upregulation indicated an unfavorable prognosis in HCC patients. CircZCCHC2 accelerated cell growth and metastasis in vitro and tumorigenicity in vivo. Mechanistic investigations revealed that circZCCHC2 regulated BTBD7 expression by sponging miR-936. Moreover, the suppression of malignancy caused by circZCCHC2 knockdown could be sufficiently reversed by miR-936 inhibition. Additionally, the suppressed Rho/ROCK2 pathway conferred by circZCCHC2 knockdown could be restored by inhibiting miR-936 expression. Collectively, our findings reveal that circZCCHC2 plays an oncogenic role of in HCC progression by modulating the miR-936/BTBD7/Rho/ROCK2 pathway.

MicroRNAs, long non-coding RNAs, and circular RNAs and gynecological cancers: focus on metastasis

Gynecologic cancer is a significant cause of death in women worldwide, with cervical cancer, ovarian cancer, and endometrial cancer being among the most well-known types. The initiation and progression of gynecologic cancers involve a variety of biological functions, including angiogenesis and metastasis-given that death mostly occurs from metastatic tumors that have invaded the surrounding tissues. Therefore, understanding the molecular pathways underlying gynecologic cancer metastasis is critical for enhancing patient survival and outcomes. Recent research has revealed the contribution of numerous non-coding RNAs (ncRNAs) to metastasis and invasion of gynecologic cancer by affecting specific cellular pathways. This review focuses on three types of gynecologic cancer (ovarian, endometrial, and cervical) and three kinds of ncRNAs (long non-coding RNAs, microRNAs, and circular RNAs). We summarize the detailed role of non-coding RNAs in the different pathways and molecular interactions involved in the invasion and metastasis of these cancers.

Circ_0021573 acts as a competing endogenous RNA to promote the malignant phenotypes of human ovarian cancer cells

Circular RNAs (circRNAs) have been reported to be implicated in the tumorigenesis and progression of ovarian cancer. Here, the study was designed to explore the activity of human circ_0021573 in ovarian cancer pathogenesis and its regulation through the competing endogenous RNA (ceRNA) crosstalk. Circ_0021573, microRNA (miR)- 936, and cullin 4B (CUL4B) were quantified by qRT-PCR and western blot. Cell proliferation ability was detected by XTT, 5-Ethynyl-2'-Deoxyuridine (EdU), and colony formation assays. Cell apoptosis, migration, and invasion were assessed by flow cytometry, wound-healing, and transwell assays, respectively. Dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were used to evaluate the direct relationship between miR-936 and circ_0021573 or CUL4B 3'UTR. Xenograft studies were applied to assess the role of circ_0021573 in tumor growth. Our data showed that circ_0021573 expression is enhanced in human ovarian cancer. Inhibition of circ_0021573 impedes cell proliferation, migration, and invasion and promotes apoptosis in vitro, as well as diminishes tumor growth in vivo. Mechanistically, circ_0021573 contains a miR-936 binding site, and miR-936 is a relevant mediator of circ_0021573 regulation. MiR-936 direct targets and inhibits CUL4B. MiR-936-mediated suppression of CUL4B hinders cell proliferation, migration, and invasion and accelerates apoptosis in vitro.. These data suggested that circ_0021573 might promote the malignant phenotypes of ovarian cancer cells by functioning as a ceRNA for miR-936 to induce CUL4B, which provided a promising target for the prevention and inhibition of ovarian cancer.

Small molecules with huge impacts: the role of miRNA-regulated PI3K pathway in human malignancies

Along with evolution, a considerable number of signaling cascades have evolved within cells to meet their multifaceted needs. Among transmitting molecules, phosphoinositide 3-kinase (PI3K), Akt, and mammalian target of rapamycin (mTOR) have teamed up to build a signaling axis that effectively regulates various cellular processes including cell proliferation and migration. Given the extensive output of the PI3K/Akt/mTOR signaling axis, its aberrancy could subsequently lead to the formation of a wide range of human cancers spanning from hematologic malignancies to different types of solid tumors. Despite the high frequency of the PI3K pathway over-activation in most malignancies, mutations in the DNA sequence are not equally common. Such incompatibility sheds light on the possible effects of post-translational modification mechanisms that may take control of this pathway, some of the most important ones of which are through microRNAs (miRNAs or miRs). The present review is designed to take off the veil from the regulatory role of these small non-coding RNAs on the PI3K/Akt/mTOR signaling axis in carcinogenesis.

In Silico Identification of miRNA-lncRNA Interactions in Male Reproductive Disorder Associated with COVID-19 Infection

Coronavirus disease 2019 (COVID-19), a global pandemic, is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Angiotensin-converting enzyme 2 (ACE2) is the receptor for SARS-CoV-2 and transmembrane serine protease 2 (TMPRSS2) facilitates ACE2-mediated virus entry. Moreover, the expression of ACE2 in the testes of infertile men is higher than normal, which indicates that infertile men may be susceptible to be infected and SARS-CoV-2 may cause reproductive disorder through the pathway induced by ACE2 and TMPRSS2. Little is known about the pathway regulation of ACE2 and TMPRSS2 expression in male reproductive disorder. Since the regulation of gene expression is mediated by microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) at the post-transcriptional level, the aim of this study was to analyze the dysregulated miRNA–lncRNA interactions of ACE2 and TMPRSS2 in male reproductive disorder. Using bioinformatics analysis, we speculate that the predicted miRNAs including miR-125a-5p, miR-125b-5p, miR-574-5p, and miR-936 as regulators of ACE2 and miR-204-5p as a modulator of TMPRSS2 are associated with male infertility. The lncRNAs with a tissue-specific expression for testis including GRM7-AS3, ARHGAP26-AS1, BSN-AS1, KRBOX1-AS1, CACNA1C-IT3, AC012361.1, FGF14-IT1, AC012494.1, and GS1-24F4.2 were predicted. The identified miRNAs and lncRNAs are proposed as potential biomarkers to study the possible association between COVID-19 and male infertility. This study encourages further studies of miRNA–lncRNA interactions to explain the molecular mechanisms of male infertility in COVID-19 patients.

Circular RNA circ_0001162 promotes cell proliferation and invasion of glioma via the miR-936/ERBB4 axis

The biological modulatory roles of many circular RNAs (circRNAs) have been validated in glioma. The current study was designed to research the functional mechanism of circ_0001162 in glioma progression. The quantitative real-time polymerase chain reaction (qRT-PCR) was used for assaying the levels of circ_0001162 and microRNA-936 (miR-936). Cell proliferation and colony formation abilities were evaluated via 3-(4, 5-dimethylthiazol-2-y1)-2, 5-diphenyl tetrazolium bromide (MTT) and colony formation assay, respectively. Transwell assay was applied to assess cell migration and invasion. The impact of circ_0001162 on glioma growth in vivo was performed using xenograft tumor assay. The target binding was affirmed via the dual-luciferase reporter and RNA pull-down assays. All protein expression levels were examined via Western blot. Circ_0001162 was an overexpressed circRNA in glioma. Circ_0001162 promoted glioma cell proliferation, colony formation, migration and invasion in vitro. Tumorigenesis of glioma in vivo was also enhanced by circ_0001162. Circ_0001162 could directly target miR-936 and the biological function of circ_0001162 in glioma was related to the inhibition of miR-936. ErbB2 receptor tyrosine kinase 4 (ERBB4) was a direct target of miR-936. Additionally, miR-936 inhibited the glioma development via targeting ERBB4. The miR-936/ERBB4 axis was responsible for the oncogenic role of circ_0001162 in glioma. The effects of circ_0001162 on glioma cells were also associated with the positive regulation of ERBB4. These results indicated that circ_0001162 contributed to the glioma progression via regulating the miR-936/ERBB4 axis, which laid a foundation for the pathomechanism and molecular treatment of glioma.

miRNA normalization enables joint analysis of several datasets to increase sensitivity and to reveal novel miRNAs differentially expressed in breast cancer

Different miRNA profiling protocols and technologies introduce differences in the resulting quantitative expression profiles. These include differences in the presence (and measurability) of certain miRNAs. We present and examine a method based on quantile normalization, Adjusted Quantile Normalization (AQuN), to combine miRNA expression data from multiple studies in breast cancer into a single joint dataset for integrative analysis. By pooling multiple datasets, we obtain increased statistical power, surfacing patterns that do not emerge as statistically significant when separately analyzing these datasets. To merge several datasets, as we do here, one needs to overcome both technical and batch differences between these datasets. We compare several approaches for merging and jointly analyzing miRNA datasets. We investigate the statistical confidence for known results and highlight potential new findings that resulted from the joint analysis using AQuN. In particular, we detect several miRNAs to be differentially expressed in estrogen receptor (ER) positive versus ER negative samples. In addition, we identify new potential biomarkers and therapeutic targets for both clinical groups. As a specific example, using the AQuN-derived dataset we detect hsa-miR-193b-5p to have a statistically significant over-expression in the ER positive group, a phenomenon that was not previously reported. Furthermore, as demonstrated by functional assays in breast cancer cell lines, overexpression of hsa-miR-193b-5p in breast cancer cell lines resulted in decreased cell viability in addition to inducing apoptosis. Together, these observations suggest a novel functional role for this miRNA in breast cancer. Packages implementing AQuN are provided for Python and Matlab: https://github.com/YakhiniGroup/PyAQN.

This work demonstrates a practical approach to the joint-analysis of multiple miRNA expression profiling datasets acquired with different measurement technologies. The use of different platforms in miRNA profiling can lead to major differences in results. In particular, some miRNA species are less amenable to detection and quantification by certain platforms or designs. Our approach, termed AQuN, combines quantile normalization with special attention to missing entities, to normalize miRNA expression across datasets, technologies, designs and platforms. As we show, our proposed approach uncovers patterns of interest that would not have emerged as statistically significant when analyzing the datasets individually or with other standard-practice normalization methods.

Amongst our findings, we noted a previously undocumented miRNA that is significantly over-expressed in samples from estrogen-receptor positive breast cancer patients as compared to samples from estrogen-receptor negative patients. We further investigated this miRNA, hsa-miR-193b-5p, and experimentally show, in cell lines, that its expression level impacts the viability of tumor cells. AQuN is available to the community in the form of Python and Matlab packages. The joint-processed data is also made available for further investigation.

MicroRNA-936 Targets JAG1 and Inhibits the Proliferation of Hepatocellular Carcinoma Cells

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors. Investigating the underlying molecular mechanism is essential for the treatment and prognosis of HCC. Emerging evidence suggests that microRNAs (miRNAs) play pivotal roles in cancer progression. Down-regulation of miR-936 has been found in several cancers, which serves as a tumor suppressor to inhibit the development of cancers. However, the clinical significance and functional roles of miR-936 in HCC have not been determined. To explore this, the expression of miR-936 in HCC tissues and cells was detected by RT-qPCR. Cell Counting Kit-8 (CCK-8) assay, cell migration and cell cycle analysis were performed to evaluate the effects of miR-936 on the growth of HCC cells. The targets of miR-936 were predicted using the miRDB database and confirmed by luciferase reporter experiments. The protein expression of targets was determined by western blot. The results showed that miR-936 was significantly decreased in HCC tissues and cell lines. Low expression of miR-936 was associated with the advance progression and poor survival of HCC patients (P = 0.0036). Functional study revealed that overexpression of miR-936 inhibited the proliferation, migration (decreased to ∼0.26 fold) and induced cell cycle arrested in G₁ phase (from 35.3% to 44.7%) of HCC cells. Additionally, miR-936 targeted the 3′-untranslated region (UTR) of jagged-1 (JAG1) and reduced the expression of JAG1 (decreased to ∼0.35 fold). JAG1 was found to be up-regulated in HCC tissues and was inversely correlated with the expression of miR-936 (Pearson r = −0.4633; P = 0.0007). The anti-cancer effects of miR-936 on the proliferation of HCC cells were partially reversed by the rescue of JAG1. Therefore, these results suggested that miR-936 might be a potential target for HCC treatment.

MicroRNA-936/ERBB4/Akt axis exhibits anticancer properties of gastric cancer through inhibition of cell proliferation, migration, and invasion

Gastric cancer is one of the most common cancers globally and has a poor prognosis. MiR-936 has been reported to regulate cell activity and tumor progression in non-small cell lung cancer, glioma, and epithelial ovarian cancer. However, the specific role and mechanism of miR-936 in gastric cancer have not been explored. In present study, gastric cancer cells were transfected with miR-936 mimic, and cell proliferation, cell cycle distribution, cell apoptosis, migration and invasion were assessed via cell-counting kit-8, flow cytometry, wound healing, and transwell assay, respectively. Dual luciferase reporter assay was used to check miR-936 binding to its downstream target. It was shown that miR-936 was downregulated in gastric cancer tissues and cells. Erb-B2 Receptor Tyrosine Kinase 4 (ERBB4) was confirmed as a direct target of miR-936 and negatively regulated its expression by miR-936. Overexpression of miR-936 suppressed cell proliferation, cell cycle progression, cell migration and invasion, and enhanced cell apoptosis in gastric cancer cells, which could be reversed by further ERBB4 overexpression. Western blot results showed that miR-936/ERBB4 axis regulated Akt-related pathways to control gastric cancer cell activities. Therefore, our data suggest that miR-936 overexpression inhibits cell proliferation and invasion and promotes cell apoptosis through Akt-related pathways by targeting ERBB4, which provides novel insight to target miR-936 or miR-936/ERBB4 axis for the treatment of gastric cancer.

The Role of microRNAs in Epithelial Ovarian Cancer Metastasis

Epithelial ovarian cancer (EOC) is the deadliest gynecological cancer, and the major cause of death is mainly attributed to metastasis. MicroRNAs (miRNAs) are a group of small non-coding RNAs that exert important regulatory functions in many biological processes through their effects on regulating gene expression. In most cases, miRNAs interact with the 3′ UTRs of target mRNAs to induce their degradation and suppress their translation. Aberrant expression of miRNAs has been detected in EOC tumors and/or the biological fluids of EOC patients. Such dysregulation occurs as the result of alterations in DNA copy numbers, epigenetic regulation, and miRNA biogenesis. Many studies have demonstrated that miRNAs can promote or suppress events related to EOC metastasis, such as cell migration, invasion, epithelial-to-mesenchymal transition, and interaction with the tumor microenvironment. In this review, we provide a brief overview of miRNA biogenesis and highlight some key events and regulations related to EOC metastasis. We summarize current knowledge on how miRNAs are dysregulated, focusing on those that have been reported to regulate metastasis. Furthermore, we discuss the role of miRNAs in promoting and inhibiting EOC metastasis. Finally, we point out some limitations of current findings and suggest future research directions in the field.

Circular RNA hsa_circ_0005909 modulates osteosarcoma progression via the miR-936/HMGB1 axis

Background

Osteosarcoma (OS) is the most common bone malignant tumor in children, youth, and adolescents. Circular RNA hsa_circ_0005909 (circ_0005909) is involved in the progression of OS. Nevertheless, there are few reports on the role and mechanism of circ_0005909 in OS.

Methods

Quantitative real-time polymerase chain reaction (qRT-PCR) was executed to examine the expression of circ_0005909, miR-936, and High Mobility Group Box 1 (HMGB1) mRNA in OS tissues and cells. Cell viability, colony formation, migration, and invasion were evaluated by Cell Counting Kit-8 (CCK-8), cell colony formation, or transwell assays. Cell epithelial-mesenchymal transition (EMT) and HMGB1 protein levels were assessed through western blot analysis. The role of circ_0005909 on tumor growth in vivo was verified by xenograft assay. The relationship between circ_0005909 or HMGB1 and miR-936 was confirmed with the dual-luciferase reporter or RNA pull-down assays.

Results

Circ_0005909 level was upregulated in OS tissues and cells. OS patients with high circ_0005909 expression had a lower survival rate. Circ_0005909 inhibition reduced tumor growth in vivo and constrained cell viability, colony formation, migration, invasion, and EMT of OS cells in vitro. Furthermore, circ_0005909 served as a sponge for miR-936 and the repressive impacts of circ_0005909 silencing on malignant behaviors of OS cells were abolished by miR-936 inhibitors. Also, HMGB1 acted as a target for miR-936 and was modulated by circ_0005909 via miR-936. Additionally, HMGB1 overexpression restored the inhibitory influence on the malignant behaviors of OS cells mediated by circ_0005909 inhibition.

Conclusions

Circ_0005909 inhibition impeded the progression of OS via downregulating HMGB1 via sponging miR-936.

Role of PI3K/AKT pathway in cancer: the framework of malignant behavior

Given that the PI3K/AKT pathway has manifested its compelling influence on multiple cellular process, we further review the roles of hyperactivation of PI3K/AKT pathway in various human cancers. We state the abnormalities of PI3K/AKT pathway in different cancers, which are closely related with tumorigenesis, proliferation, growth, apoptosis, invasion, metastasis, epithelial-mesenchymal transition, stem-like phenotype, immune microenvironment and drug resistance of cancer cells. In addition, we investigated the current clinical trials of inhibitors against PI3K/AKT pathway in cancers and found that the clinical efficacy of these inhibitors as monotherapy has so far been limited despite of the promising preclinical activity, which means combinations of targeted therapy may achieve better efficacies in cancers. In short, we hope to feature PI3K/AKT pathway in cancers to the clinic and bring the new promising to patients for targeted therapies.

Eukaryotic initiation factor 3B is overexpressed and correlates with larger tumor size, advanced FIGO stage, and shorter overall survival in epithelial ovarian cancer patients

Background

This study aimed to detect the eukaryotic initiation factor 3B (EIF3B) expression and explore its correlation with clinical features and prognosis in epithelial ovarian cancer (EOC) patients.

Methods

A total of 230 primary EOC patients underwent surgery treatment were retrospectively reviewed. Immunohistochemical (IHC) assay was used to determine EIF3B expression in tumor and adjacent tissue specimens of all patients. According to the total IHC score, the expression of EIF3B was classified as low expression and high expression, and the latter was further divided into 3 grades: high+, high++, and high+++ expressions. Overall survival (OS) was calculated.

Results

Eukaryotic initiation factor 3B expression was increased in tumor tissue compared with adjacent tissue. Tumor EIF3B high expression correlated with larger tumor size (>10 cm), lymphatic metastasis, and advanced International Federation of Gynecology and Obstetrics stage (FIGO) (III/IV). Besides, OS was decreased in patients with tumor EIF3B high expression compared with patients with tumor EIF3B low expression, and further analysis showed that the OS was shortest in patients with tumor EIF3B high+++ expression, followed by patients with tumor EIF3B high++ expression and patients with tumor EIF3B high + expression, and the longest in patients with tumor EIF3B low expression. Additionally, higher tumor EIF3B expression, peritoneal cytology (positive), ascites volume (>100 mL), differentiation (poor vs. well/moderate), tumor size (>10 cm), FIGO stage (III/IV vs. I/II), and cancer antigen 125 (>1000 U/mL) independently predicted shorter OS.

Conclusion

Eukaryotic initiation factor 3B exhibits a clinical value for monitoring disease progression and predicting prognosis in EOC patients.

Inhibition of long non-coding RNA-AWPPH decreases osteosarcoma cell proliferation, migration and invasion

Long non-coding RNAs (lncRNAs) serve a crucial role in various types of cancer. The lncRNA AWPPH has been reported to promote hepatocellular carcinoma and bladder cancer progression. However, to the best of our knowledge, the biological roles of AWPPH in osteosarcoma (OS) remain unclear. In the present study, the levels of AWPPH in OS tissues and cell lines were determined by reverse transcription-quantitative polymerase chain reaction. An MTT assay was used to detect OS cell proliferation. The levels of proteins associated with the PI3K/Akt signaling pathway and apoptosis were determined by western blotting. Wound-healing and Transwell assays were conducted to determine cell migration and invasion, respectively. The results demonstrated that AWPPH was highly expressed in OS tissues and cells. Functional analyses revealed that AWPPH depletion significantly inhibited OS cell proliferation and migration, and promoted OS cell apoptosis. Furthermore, AWPPH downregulation significantly inhibited the PI3K/AKT pathway. The present study demonstrated that AWPPH was highly expressed in OS, and that AWPPH promoted OS cell proliferation and migration, and inhibited OS cell apoptosis, which may be mediated by PI3K/AKT pathway activation.