Downregulation of miR-139-5p promotes prostate cancer progression through regulation of SOX5

Prostate cancer and the cell cycle: Focusing on the role of microRNAs

Prostate cancer is the most frequent solid tumor in terms of incidence and ranks second only to lung cancer in terms of cancer mortality among men. It has a considerably high mortality rate; around 375,000 deaths occurred worldwide in 2020. In 2024, the American Cancer Society estimated that the number of new prostate cancer cases will be around 299,010 cases, and the estimated deaths will be around 32,250 deaths only in the USA. Cell cycle dysregulation is inevitable in cancer etiology and is targeted by various therapies in cancer treatment. MicroRNAs (miRNAs) are small, endogenous, non-coding regulatory molecules involved in both normal and abnormal cellular events. One of the cellular processes regulated by miRNAs is the cell cycle. Although there are some exceptions, tumor suppressor miRNAs could potentially arrest the cell cycle by downregulating several molecular machineries involved in catalyzing the cell cycle progression. In contrast, oncogenic miRNAs (oncomirs) help the cell cycle to progress by targeting various regulatory proteins such as retinoblastoma (Rb) or cell cycle inhibitors such as p21 or p27, and hence may contribute to prostate cancer progression; however, this is not always the case. In this review, we emphasize how a dysregulated miRNA expression profile is linked to an abnormal cell cycle progression in prostate cancer, which subsequently paves the way to a new therapeutic option for prostate cancer.

Biological functions and therapeutic potential of SRY related high mobility group box 5 in human cancer

Cancer is a heavy human burden worldwide, with high morbidity and mortality. Identification of novel cancer diagnostic and prognostic biomarkers is important for developing cancer treatment strategies and reducing mortality. Transcription factors, including SRY associated high mobility group box (SOX) proteins, are thought to be involved in the regulation of specific biological processes. There is growing evidence that SOX transcription factors play an important role in cancer progression, including tumorigenesis, changes in the tumor microenvironment, and metastasis. SOX5 is a member of SOX Group D of Sox family. SOX5 is expressed in various tissues of human body and participates in various physiological and pathological processes and various cellular processes. However, the abnormal expression of SOX5 is associated with cancer of various systems, and the abnormal expression of SOX5 acts as a tumor promoter to promote cancer cell viability, proliferation, invasion, migration and EMT through multiple mechanisms. In addition, the expression pattern of SOX5 is closely related to cancer type, stage and adverse clinical outcome. Therefore, SOX5 is considered as a potential biomarker for cancer diagnosis and prognosis. In this review, the expression of SOX5 in various human cancers, the mechanism of action and potential clinical significance of SOX5 in tumor, and the therapeutic significance of Sox5 targeting in cancer were reviewed. In order to provide a new theoretical basis for cancer clinical molecular diagnosis, molecular targeted therapy and scientific research.

Effect and Mechanism of lncRNA-PCMF1/hsa-miR-137/Twist1 Axis Involved in the EMT Regulation of Prostate Cancer Cells

The metastasis is a major reason for the poor prognosis of the patients with prostate cancer (PC). Currently, androgen deprivation therapy (ADT) is the basic method for the treatment of PC regardless of surgery or drug treatments. However, ADT therapy is generally not recommended for patients with advanced/metastatic PC. Herein, we report for the first time a long non-coding RNA (lncRNA)-PCMF1 which promotes the progression of Epithelial-Mesenchymal Transition (EMT) in PC cells. Our data demonstrated that PCMF1 in metastatic PC tissues increased significantly compared to non-metastatic specimens. Mechanism research showed that PCMF1 could competitively bind to hsa-miR-137 instead of the 3' -Untranslated Region (UTR) of Twist Family BHLH Transcription Factor 1 (Twist1) by acting as an endogenous miRNA sponge. Furthermore, we found that silence of PCMF1 effectively blocked the EMT in PC cells by indirectly suppressing Twist1 protein mediated by hsa-miR-137 at post-transcriptional level. In summary, our research shows that PCMF1 promotes the EMT of PC cells by causing the functional inactivation of hsa-miR-137 on Twist1 protein, which is an independent risk factor of PC. PCMF1 knockdown combined with hsa-miR-137 expression is a promising PC-targeted therapy. Furthermore, PCMF1 is also expected to act as a useful marker for predicting malignant changes and assessing the prognosis of PC patients.

LncRNA AC012360.1 facilitates growth and metastasis by regulating the miR-139-5p/LPCAT1 axis in hepatocellular carcinoma

Long noncoding RNAs (lncRNAs) participate in tumorigenesis and tumor progression. However, whether lncRNA AC012360.1 contributes to hepatocellular carcinoma (HCC) is unknown. In HCC tissues, differentially expressed lncRNAs were identified by bioinformatics. AC012360.1 level was validated and its role in HCC progression was investigated. Among the top 10 upregulated lncRNAs, AC012360.1 exhibited the greatest increase in HCC tissues. Additionally, AC012360.1 was upregulated in HCC tissues/cells. Moreover, AC012360.1 knockdown refrained cell proliferation/metastasis and tumor growth. Conversely, AC012360.1 overexpression showed an oncogenic role. AC012360.1 and lysophosphatidylcholine acyltransferase 1 (LPCAT1) contained miR-139-5p binding sites. Furthermore, miR-139-5p silencing partially mitigated the role of AC012360.1 knockdown, while LPCAT1 knockdown partially abolished the tumor-promoting effect of AC012360.1 overexpression. In conclusion, AC012360.1 exhibited its oncogenic function in HCC through sponging miR-139-5p and upregulating LPCAT1 expression.

MicroRNA-139-5p suppresses non-small cell lung cancer progression by targeting ATAD2

MiR-139-5p is a suppressor in multiple types of cancer. However, whether miR-139-5p affects NSCLC is unknown. In this study, miR-139-5p expression in clinical samples was examined by real-time PCR and in situ hybridization (ISH). MiR-139-5p mimic was transfected to monitor NSCLC cell behaviors. Potential target was predicated using bioinformatics database. Next, whether miR-139-5p impacted cell behaviors via regulation of its predicted target gene were further evaluated. The result revealed that miR-139-5p was lower in NSCLC samples/cells. MiR-139-5p restrained A549 cell proliferation, accelerated apoptosis, and inhibited the β-catenin signaling. ATAD2 was a predicted target of miR-139-5p, and it was highly expressed in NSCLC tissues. ATAD2 overexpression abolished the miR-139-5p's anti-tumor effect on cell proliferation and apoptosis. TWS119 (a β-catenin signaling activator) partially reversed miR-139-5p overexpression-induced suppression of cell proliferation and promotion of cell apoptosis. In tumor xenografts, miR-139-5p restrained tumor growth. MiR-139-5p was a tumor suppressor in NSCLC by regulating the oncogene ATAD2 and β-catenin signaling. Our study provides a promising target for cancer treatment.

FTO-stabilized miR-139-5p targets ZNF217 to suppress prostate cancer cell malignancies by inactivating the PI3K/Akt/mTOR signal pathway

As one of the most important demethylases for RNA N6-methyladenosine (m6A) modifications, fat mass and obesity-associated protein (FTO) plays anti-cancer role during prostate cancer (PC), but it is still unclear the detailed molecular mechanisms. Here, this study verified that FTO inactivated the tumor-accelerating PI3K/Akt/mTOR pathway to hamper PC development through regulating the downstream miR-139-5p/zinc finger protein 217 (ZNF217) axis. Through performing clinical analysis, it was revealed that FTO was apparently ablated in the cancerous tissues compared to the normal tissues collected from PC patients, and patients with high-expressed FTO predicted a favorable prognosis. Functional experiments confirmed that overexpression of FTO suppressed cell proliferation, mitosis, epithelial-mesenchymal transition (EMT), tumorigenesis and lung metastasis both in vitro and in vivo. The following mechanical experiments verified that FTO stabilized miR-139-5p to increase its expression levels in a m6A-dependent manner, and elevated miR-139-5p induced degradation of ZNF217 through binding to ZNF217 mRNA, resulting in the inactivation of the PI3K/Akt/mTOR signal pathway. Finally, our rescuing experiments confirmed that overexpressed FTO-induced tumor-suppressing effects on PC cells were abrogated by miR-139-5p ablation and ZNF217 overexpression. Collectively, this study firstly validated that FTO exerted its anti-tumor effects in PC through regulating the miR-139-5p/ZNF217 axis in a m6A-dependent manner, providing novel biomarkers for the advancement of anti-cancer agents for PC treatment.

Differential Expression of miRNAs Contributes to Tumor Aggressiveness and Racial Disparity in African American Men with Prostate Cancer

Prostate cancer is the leading cancer in incidence and second leading cause of cancer mortality in US men. African American men have significantly higher incidence and mortality rates from prostate cancer than European American men. Previous studies reported that the disparity in prostate cancer survival or mortality can be explained by different biological backgrounds. microRNAs (miRNAs) regulate gene expression of their cognate mRNAs in many cancers. Therefore, miRNAs may be a potentially promising diagnostic tool. The role of miRNAs in prostate cancer aggressiveness and racial disparity has not been fully established. The goal of this study is to identify miRNAs associated with aggressiveness and racial disparity in prostate cancer. Here we report miRNAs that are associated with tumor status and aggressiveness in prostate cancer using a profiling approach. Further, downregulated miRNAs in African American tissues were confirmed by qRT-PCR. These miRNAs have also been shown to negatively regulate the expression of the androgen receptor in prostate cancer cells. This report provides a novel insight into understanding tumor aggressiveness and racial disparities of prostate cancer.

Expression Profiles, Prognosis, and ceRNA Regulation of SRY-Related HMG-Box Genes in Stomach Adenocarcinoma

Aberrant expression of the SRY-related HMG-box (SOX) genes contributes to tumor development and progression. This research aimed to identify the regulation of the SOX genes in stomach adenocarcinoma (STAD). Expression profiles downloaded from The Cancer Genome Atlas (TCGA) were conducted to analyze the expression and function of the SOX genes. A competing endogenous RNAs (ceRNA) network mediated by the SOX genes was effectively constructed consisting of 64 lncRNAs, 29 miRNAs, and 11 SOX genes based on predicted miRNAs shared by lncRNAs and mRNAs using miRDB, TargetScan, miRTarBase, miRcode, and starBase v2.0. SOX9 was identified as a prognostic signature, which showed the usefulness of diagnosis and prognosis of STAD by the receiver operating characteristic (ROC) and Kaplan-Meier curves. SOX9 was also shown specifically in STAD and identified as highly expressed in the gastrointestinal tract. Gene Ontology (GO) enrichment analysis showed that SOX9 might influence the genes related to the pattern specification process, sodium ion homeostasis, and potassium ion transport, mainly including FEZF1, HOXC13, HOXC10, HOXC9, HOXA11, DPP6, ATP4B, CASQ2, KCNA1, ATP4A, and SFRP1. Furthermore, HOTAIR knockdown, miR-206-mimic transfection, the Cell Count Kit-8 (CCK-8) assay were performed to verify the function of HOTAIR/miR-206/SOX9 axis, which was identified in the ceRNA network analysis. HOTAIR could induce proliferation potentially by competitively binding miR-206/SOX9 axis in STAD. These findings provide new clues with prognostic and therapeutic implications in STAD and suggest that HOTAIR/miR-206/SOX9 might be a potential new strategy for therapeutic targeting of gastric cancer.

Circ_0068631 sponges miR-139-5p to promote the growth and metastasis of cutaneous squamous cell carcinoma by upregulating HOXB7

BACKGROUND

Circular RNAs (circRNAs) are often dysregulated in cancers and closely related to cancer progression, including cutaneous squamous cell carcinoma (CSCC). However, the role and mechanism of circ_0068631 in CSCC progression have not been reported.

METHODS

The expression of circ_0068631, microRNA-139-5p (miR-139-5p), and homeobox B7 (HOXB7) was measured by real-time quantitative polymerase chain reaction (RT-qPCR). Cell counting kit-8 (CCK-8) assay, 5-ethynyl-2'-deoxyuridine (EdU) assay, and colony formation assay were used to measure cell proliferation. Cell apoptosis was assessed by flow cytometry. Cell migration was detected by transwell assay. The interaction between miR-139-5p and circ_0068631 or HOXB7 was confirmed by dual-luciferase reporter assay. A xenograft tumor model was established to confirm the function of circ_0068631 in vivo.

RESULTS

Circ_0068631 was upregulated in CSCC tissues and cells, and its silencing could inhibit CSCC cell proliferation and metastasis while promoting apoptosis in vitro, as well as restrain CSCC tumor growth in vivo. Circ_0068631 acted as a sponge of miR-139-5p, and miR-139-5p inhibition reversed the repressive effect of circ_0068631 knockdown on CSCC cell progression. Furthermore, HOXB7 was a target of miR-139-5p, and miR-139-5p inhibited the malignant behaviors by downregulating HOXB7 expression in CSCC cells. Further, circ_0068631 sponged miR-139-5p to regulate HOXB7 expression.

CONCLUSION

Circ_0068631 functioned as a novel oncogene in CSCC progression by regulating miR-139-5p/HOXB7 axis, suggesting that circ_0068631 may be a potential target for CSCC treatment.

HIGHLIGHTS

Circ_0068631 was overexpressed in CSCC tissues and cells. Circ_0068631 downregulation suppressed CSCC progression via miR-139-5p. Circ_0068631 regulated HOXB7 via sponging miR-139-5p.

The Role of MicroRNA in the Regulation of Tumor Epithelial–Mesenchymal Transition

Consistently, the high metastasis of cancer cells is the bottleneck in the process of tumor treatment. In this process of metastasis, a pivotal role is executed by epithelial–mesenchymal transition (EMT). The epithelial-to-mesenchymal transformation was first proposed to occur during embryonic development. Later, its important role in explaining embryonic developmental processes was widely reported. Recently, EMT and its intermediate state were also identified as crucial drivers in tumor progression with the gradual deepening of research. To gain insights into the potential mechanism, increasing attention has been focused on the EMT-related transcription factors. Correspondingly, miRNAs target transcription factors to control the EMT process of tumor cells in different types of cancers, while there are still many exciting and challenging questions about the phenomenon of microRNA regulation of cancer EMT. We describe the relevant mechanisms of miRNAs regulating EMT, and trace the regulatory roles and functions of major EMT-related transcription factors, including Snail, Twist, zinc finger E-box-binding homeobox (ZEB), and other families. In addition, on the basis of the complex regulatory network, we hope that the exploration of the regulatory relationship of non-transcription factors will provide a better understanding of EMT and cancer metastasis. The identification of the mechanism leading to the activation of EMT programs during diverse disease processes also provides a new protocol for the plasticity of distinct cellular phenotypes and possible therapeutic interventions. Here, we summarize the recent progress in this direction, with a promising path for further insight into this fast-moving field.

Transforming growth factor-beta (TGF-β) in prostate cancer: A dual function mediator?

Transforming growth factor-beta (TGF-β) is a member of a family of secreted cytokines with vital biological functions in cells. The abnormal expression of TGF-β signaling is a common finding in pathological conditions, particularly cancer. Prostate cancer (PCa) is one of the leading causes of death among men. Several genetic and epigenetic alterations can result in PCa development, and govern its progression. The present review attempts to shed some light on the role of TGF-β signaling in PCa. TGF-β signaling can either stimulate or inhibit proliferation and viability of PCa cells, depending on the context. The metastasis of PCa cells is increased by TGF-β signaling via induction of EMT and MMPs. Furthermore, TGF-β signaling can induce drug resistance of PCa cells, and can lead to immune evasion via reducing the anti-tumor activity of cytotoxic T cells and stimulating regulatory T cells. Upstream mediators such as microRNAs and lncRNAs, can regulate TGF-β signaling in PCa. Furthermore, some pharmacological compounds such as thymoquinone and valproic acid can suppress TGF-β signaling for PCa therapy. TGF-β over-expression is associated with poor prognosis in PCa patients. Furthermore, TGF-β up-regulation before prostatectomy is associated with recurrence of PCa. Overall, current review discusses role of TGF-β signaling in proliferation, metastasis and therapy response of PCa cells and in order to improve knowledge towards its regulation, upstream mediators of TGF-β such as non-coding RNAs are described. Finally, TGF-β regulation and its clinical application are discussed.

MiR-139-5p Targeting CCNB1 Modulates Proliferation, Migration, Invasion and Cell Cycle in Lung Adenocarcinoma

Lung adenocarcinoma (LUAD) is the most frequent histological subtype of non-small cell lung cancer. Cyclin B1 (CCNB1) is the vital initiator and controller of mitosis. Studies have indicated that CCNB1 overexpression is closely associated with cell proliferation and tumorigenesis in many cancers. Thus, discovery of molecular mechanism of CCNB1 in LUAD is conducive to developing new diagnostic or therapeutic targets for LUAD. We acquired mature miRNA and mRNA expression information of LUAD from TCGA database, as well as related clinical data. CCNB1 expression in normal and LUAD tissue was analyzed. Relationship between CCNB1 and patient's survival and clinical stage was analyzed. Upstream regulatory gene miRNA of CCNB1 was predicted. qRT-PCR and western blot examined expression levels of CCNB1 and miR-139-5p in cells. CCK-8 tested cell proliferation. Scratch healing and Transwell determined cell migration and invasion. Flow cytometry analyzed the cell cycle. Dual-luciferase verified targeting relationship between the two genes. Compared to controls, CCNB1 expression was prominently high in LUAD patient samples, and associated with advanced tumor stages and shorter overall survival. MiR-139-5p expressed an evidently negative correlation with CCNB1 and was predicted to target CCNB1. MiR-139-5p mimics reduced CCNB1 mRNA and protein expression, and suppressed luciferase activity in a target-specific manner, as confirmed by a control construct with a mutated miR-139-5p binding site. CCNB1 overexpression fostered progression of LUAD cells. Mechanistically, miR-139-5p might negatively regulate CCNB1 in LUAD, thereby suppressing cell proliferation, migration, invasion and cell cycle.

The Role of MiRNA in Cancer: Pathogenesis, Diagnosis, and Treatment

Cancer is also determined by the alterations of oncogenes and tumor suppressor genes. These gene expressions can be regulated by microRNAs (miRNA). At this point, researchers focus on addressing two main questions: "How are oncogenes and/or tumor suppressor genes regulated by miRNAs?" and "Which other mechanisms in cancer cells are regulated by miRNAs?" In this work we focus on gathering the publications answering these questions. The expression of miRNAs is affected by amplification, deletion or mutation. These processes are controlled by oncogenes and tumor suppressor genes, which regulate different mechanisms of cancer initiation and progression including cell proliferation, cell growth, apoptosis, DNA repair, invasion, angiogenesis, metastasis, drug resistance, metabolic regulation, and immune response regulation in cancer cells. In addition, profiling of miRNA is an important step in developing a new therapeutic approach for cancer.

MicroRNA-139-5p Suppresses Cell Malignant Behaviors in Breast Cancer through Targeting MEX3A

OBJECTIVE

The study was designed to evaluate the underlying mechanism of microRNA-139-5p in breast cancer (BC).

METHODS

Expression statuses of microRNA-139-5p and MEX3A were measured by qRT-PCR and western blotting. The anticancer effect of microRNA-139-5p in vitro was tested by a set of assays. Interaction between microRNA-139-5p and MEX3A was validated by dual-luciferase detection.

RESULTS

MicroRNA-139-5p expression in BC cells was obviously low, while MEX3A was significantly overexpressed. MicroRNA-139-5p restrained proliferative, invasive, and migratory abilities of BC cells and increased apoptosis level of BC cells, while MEX3A exerted a promoting effect on BC cell growth. Dual-luciferase reporter detection confirmed that microRNA-139-5p bound to MEX3A 3'-UTR.

CONCLUSIONS

MicroRNA-139-5p inhibited the development of BC by targeting MEX3A. MicroRNA-139-5p/MEX3A may be a target for BC therapy.

miRNA-877-5p inhibits malignant progression of prostate cancer by directly targeting SSFA2

In this study, we aimed to investigate the role of miR-877-5p in the malignant phenotypes of prostate cancer (PCa) cells and its underlying mechanism. RT-qPCR analysis was performed to examine the expression of miR- 877-5p and sperm-specific antigen 2 (SSFA2) in PCa tissues and cells. Cell counting kit-8 (CCK-8) assay, 5- ethynyl-20-deoxyuridine (EdU) assay, flow cytometry, wound-healing assay, and Transwell invasion assay were performed to determine the functional roles of miR-877-5p in PCa cells. The association of miR-877-5p with SSFA2 was determined by luciferase reporter and RNA pull-down assays. In this study, we found that the expression level of miR-877-5p was decreased in PCa tissues and cells. Functionally, overexpression of miR- 877-5p exerted tumor suppressor properties in PCa cells. Mechanistically, SSFA2 was identified as a target gene of miR-877-5p, while overexpression of SSFA2 could abrogate the anti-tumor effects of miR-877-5p in PCa cells. These findings demonstrated that miR-877-5p/SSFA2 axis functioned as a potential target for PCa treatment.

MiR-129-5p/DLX1 signalling axis mediates functions of prostate cancer during malignant progression

We mainly corroborated the potential mechanism of DLX1 and miR-129-5p in prostate cancer cells. DLX1 was upregulated in cancer cells according to qRT-PCR assay. We evaluated the functional changes of the transfected cells via Transwell assay, CCK-8 assay and wound healing assay. DLX1 was confirmed as a cancer promoter. In addition, qRT-PCR showed down-regulated miR-129-5p expression in prostate cancer. We further used dual-luciferase reporter detection to elucidate the targeting between these two genes. The inhibition of miR-129-5p on tumour was verified. Besides, co-transfection of oe-DLX1 and miR-129-5p mimics attenuated this inhibition. These data demonstrated functions of DLX1/miR-129-5p axis in prostate cancer: miR-129-5p hindered the biological functions of cancer cells via inhibiting DLX1 expression. We provide a novel biomarker for prostate cancer.

Long non-coding RNA CRNDE regulates the growth and migration of prostate cancer cells by targeting microRNA-146a-5p

The function of lncRNA CRNDE and its role in prostate cancer (PC) remains unclear. The aim of this study was to determine the expression level of lncRNA CRNDE in PC tissues and to elucidate its role in PC. The expression levels of lncRNA CRNDE were measured by quantitative reverse transcription polymerase chain reaction. The role of lncRNA CRNDE in PC cells was studied using loss-of-function assays in vitro. Cell proliferation, migration, invasion, and apoptosis were assessed via Cell Counting Kit-8, colony formation, flow cytometry, wound healing, and transwell chamber assays. A luciferase reporter assay was used to characterize the interaction between lncRNA CRNDE and miR-146a-5p. In PC tissues, the expression level of lncRNA CRNDE was upregulated. Moreover, knockdown of lncRNA CRNDE suppressed PC cell proliferation and migration and induced apoptosis in vitro. miR-146a-5p was verified as a direct target of lncRNA CRNDE. Moreover, the inhibition of miR-146a-5p partially counteracted the effects of lncRNA CRNDE on PC cell proliferation, migration, and invasion. In conclusion, lncRNA CRNDE may serve as a cancer promoter in PC by targeting miR-146a-5p. Therefore, lncRNA CRNDE could be a promising target for the clinical treatment of PC.

LncRNA HCP5 promotes malignant cell behaviors in esophageal squamous cell carcinoma via the PI3K/AKT/mTOR signaling

The role of lncRNA HCP5 in esophageal squamous cell carcinoma (ESCC) remains unknown despite its involvement in different malignancies. MTT assay, EdU assay, TUNEL assay, transwell assay, and sphere formation assay were conducted to reveal ESCC cell viability, proliferation, apoptosis, migration, invasion, and stemness characteristics. FISH and subcellular fraction assays were performed to reveal the subcellular location of HCP5 in ESCC cells. Luciferase reporter assay and RIP assay were conducted to explore the downstream axis of HCP5. Our findings revealed that HCP5 expression was at a higher level in ESCC tissues and cells compared to that in control tissues and cells. Additionally, HCP5 promoted ESCC cellular activities by promoting proliferation, migration, invasion ability and stemness characteristics of ESCC cells as well as suppressing cell apoptosis. Furthermore, we found that HCP5 bound with miR-139-5p to upregulate PDE4A via the competing endogenous RNA network in ESCC cells. Importantly, HCP5 was discovered to stimulate the PI3K/AKT/mTOR signaling by regulating the downstream target genes. Finally, rescue assays indicated that HCP5 promoted ESCC cell growth by activating the PDE4A-medaited PI3K/AKT/mTOR pathway. HCP5 promotes ESCC cellular development by modulating the miR-139-5p/PDE4A pathway and stimulating the PI3K/AKT/mTOR signaling pathway, which may be conducive for the improvement of ESCC treatment.

MiR-139 Modulates Cancer Stem Cell Function of Human Breast Cancer through Targeting CXCR4

Elevated expression of C-X-C motif chemokine receptor 4 (CXCR4) correlates with chemotaxis, invasion, and cancer stem cell (CSC) properties within several solid-tumor malignancies. Recent studies reported that microRNA (miRNA) modulates the stemness of embryonic stem cells. We aimed to investigate the role of miRNA, via CXCR4-modulation, on CSC properties in breast cancer using cell lines and xenotransplantation mouse model and evaluated miR-193 levels in 191 patients with invasive ductal carcinoma. We validated miR-139 directly targets the 3'-untranslated region of CXCR4. Hoechst 33342 fluorescence-activated cell sorting (FACS) and sphere-forming assay were used to identify CSCs. MiR-139 suppressed breast CSCs with mesenchymal traits; led to decreased migration and invasion abilities through down-regulating CXCR4/p-Akt signaling. In lung cancer xenograft model of nude mice transplanted with human miR-139-carrying MDA-MB-231 cells, metastatic lung nodules were suppressed. Clinically, microdissected breast tumor tissues showed miR-139 reduction, compared to adjacent non-tumor tissues, that was significantly associated with worse clinicopathological features, including larger tumor size, advanced tumor stage and lymph node metastasis; moreover, reduced miR-139 level was predominately occurred in late-stage HER2-oreexpression tumors. Collectively, our findings highlight miR-139-mediated suppression of CXCR4/p-Akt signaling and thereby affected mesenchymal stem-cell genesis, indicating its potential as a therapeutic target for invasive breast cancer.

Identification of MicroRNAs as Diagnostic Biomarkers for Breast Cancer Based on the Cancer Genome Atlas

Breast cancer is the most common cancer among women worldwide. MicroRNAs (miRNAs or miRs) play an important role in tumorigenesis, and thus, they have been identified as potential targets for translational research with diagnostic, prognostic, and therapeutic markers. This study aimed to identify differentially expressed (DE) miRNAs in breast cancer using the Cancer Genome Atlas. The miRNA profiles of 755 breast cancer tissues and 86 adjacent non-cancerous breast tissues were analyzed using Multi Experiment Viewer; miRNA–mRNA network analyses and constructed KEGG pathways with the predicted target genes were performed. The clinical relevance of miRNAs was investigated using area under the receiver operating characteristic curve (AUC) analysis, sensitivity, and specificity. The analysis identified 28 DE miRNAs in breast cancer tissues, including nine upregulated and 19 downregulated miRNAs, compared to non-cancerous breast tissues (p < 0.001). The AUC for each DE miRNA, miR-10b, miR-21, miR-96, miR-99a, miR-100, miR-125b-1, miR-125b-2, miR-139, miR-141, miR-145, miR-182, miR-183, miR-195, miR-200a, miR-337, miR-429, and let-7c, exceeded 0.9, indicating excellent diagnostic performance in breast cancer. Moreover, 1381 potential target genes were predicted using the prediction database tool, miRNet. These genes are related to PD-L1 expression and PD-1 checkpoint in cancer, MAPK signaling, apoptosis, and TNF pathways; hence, they regulate the development, progression, and immune escape of cancer. Thus, these 28 miRNAs can serve as prospective biomarkers for the diagnosis of breast cancer. Taken together, these results provide insight into the pathogenic mechanisms and potential therapies for breast cancer.

Identification of a novel six autophagy-related genes signature for the prognostic and a miRNA-related autophagy predictor for anti-PD-1 therapy responses in prostate cancer

Background

Autophagy is a highly conserved homeostatic process in the human body that is responsible for the elimination of aggregated proteins and damaged organelles. Several autophagy-related genes (ARGs) contribute to the process of tumorigenesis and metastasis of prostate cancer (PCa). Also, miRNAs have been proven to modulate autophagy by targeting some ARGs. However, their potential role in PCa still remains unclear.

Methods

An univariate Cox proportional regression model was used to identify 17 ARGs associated with the overall survival (OS) of PCa. Then, a multivariate Cox proportional regression model was used to construct a 6 autophagy-related prognostic genes signature. Patients were divided into low-risk group and high-risk group using the median risk score as a cutoff value. High-risk patients had shorter OS than low-risk patients. Furthermore, the signature was validated by ROC curves. Regarding mRNA and miRNA, 12 differentially expressed miRNAs (DEMs) and 1073 differentially expressed genes (DEGs) were detected via the GEO database. We found that miR-205, one of the DEMs, was negatively regulated the expression of ARG (NKX2–3). Based on STRING analysis results, we found that the NKX2–3 was moderately related to the part of genes among the 6 autophagy-related genes prognostic signature. Further, NKX 2–3 was significantly correlated with OS and some clinical parameters of PCa by cBioProtal. By gene set enrichment analysis (GSEA). Lastly, we demonstrated that the association between NKX2–3 and tumor mutation burden (TMB) and PDCD1 (programmed cell death 1) of PCa.

Results

We identified that the six ARGs expression patterns are independent predictors of OS in PCa patients. Furthermore, our results suggest that ARGs and miRNAs are inter-related. MiR-205 was negatively regulated the expression of ARG (NKX2–3). Further analysis demonstrated that NKX2–3 may be a potential biomarker for predicting the efficacy of anti-PD-1 therapy in PCa.

Conclusions

The current study may offer a novel autophagy-related prognostic signature and may identify a promising miRNA-ARG pathway for predicting the efficacy of anti-PD-1 therapy in PCa.

Roles of the miR-139-5p/CCT5 axis in hepatocellular carcinoma: a bioinformatic analysis

Background: MiRNAs are pivotal regulators involved in proliferation, apoptosis, invasion, metastasis, epithelial-mesenchymal transition (EMT), angiogenesis, drug resistance and autophagy in hepatocellular carcinoma (HCC). The aim of this study was to investigate the influence of miR-139-5p and its target genes on the outcomes of HCC. Methods: Survival analysis of miR-139-5p in HCC was conducted in Kaplan-Meier plotter. Target genes of miR-139-5p were identified in TargetScan, miRTarBase and starBase. Gene Expression Omnibus (GEO) series were used for the validation of miR-139-5p target genes. Cox proportional regression model was also established. Results: In Kaplan-Meier plotter, 163 HCC patients were included. MiR-139-5p downregulation was significantly associated with unfavorable overall survival (OS) and disease-free survival (DFS) in HCC patients (all P < 0.001). MiR-139-5p was significantly downregulated in HCC tumors and human hepatoma cell lines (all P < 0.05). As a target gene of miR-139-5p, CCT5 was overexpressed in HCC tumor tissues and peripheral blood mononuclear cells (all P < 0.05). A negative correlation between CCT5 and miR-139-5p was found in TCGA dataset. CCT5 overexpression was significantly associated with worse OS in HCC patients (P < 0.001), which was validated in the GSE14520 dataset (P = 0.017). CCT5 mRNA was significantly overexpressed in HCC patients with alpha-fetoprotein (AFP) > 300 ng/ml, BCLC staging B-C, TNM staging III and main tumor size > 5 cm (all P < 0.05). According to the Cox regression model of CCT5-interacting genes, HCC patients with high risk had poor OS compared to those with low risk in the TCGA dataset (P < 0.001), with the 1-year, 3-year, and 5-year ROC curves of an area under the curve (AUC) equal to 0.704, 0.662, and 0.631, respectively. Conclusions: MiR-139-5p suppresses HCC tumor aggression and conversely correlated with CCT5. The miR-139-5p/CCT5 axis might perform crucial functions in the development of HCC.

lncRNA SNHG3 acts as oncogene in ovarian cancer through miR-139-5p and Notch1

Ovarian cancer (OC) is a common malignant tumor of the female reproductive system. Long non-coding RNAs (lncRNAs) play an important role in OC occurrence and development. Thus, the function and potential mechanism of lncRNA small nucleolar RNA host gene 3 (SNHG3) was explored in the development of OC. The expression of SNHG3, microRNA (miR)-139-5p and Notch homolog 1, translocation-associated (Drosophila) (Notch1) in OC were detected by RT-qPCR or western blot assay. In addition, CCK-8 and wound-healing assays were used to detect OVCAR3 proliferation and migration ability. The targeting relationship of miR-139-5p with SNHG3 or Notch1 was verified through luciferase reporter assay. Rescue experiments were performed to confirm whether SNHG3 could mediate OVCAR3 proliferation and migration through miR-139-5p and Notch1. In OC tissues and cell lines, the expression of SNHG3 and Notch1 were significantly increased, and the expression of miR-139-5p was significantly decreased. SNHG3 inhibition suppressed the proliferation and migration of OVCAR3 cells. Luciferase reporter experiment confirmed that miR-139-5p could target SNHG3 and Notch1. Transfection of miR-139-5p inhibitor significantly reversed the inhibitory effect of SNHG3 knockdown on OVCAR3 proliferation and migration. Moreover, SNHG3 inhibition or miR-139-5p mimic abolished the promotion of Notch1 overexpression on OVCAR3 proliferation and migration. In conclusion, SNHG3 could accelerate the proliferation and migration of OC cells by regulating miR-139-5p and Notch1.

MiR-139-5p-ZEB1 is a Molecular Regulator of Growth, Invasion, and Epithelial-to-Mesenchymal Transition of Cervical Cancer

Objective

To verify that miR-139-5p-zinc finger E-box-binding homeobox 1 (ZEB1) is a molecular regulator of the biological function and epithelial–mesenchymal transition (EMT) of cervical cancer (CC) cells.

Methods

Cancerous tissues, corresponding paracancerous tissues, and serum were sampled from patients with CC. MiR-139-5p and ZEB1 in tissue specimens, serum specimens, and purchased CC cell lines were quantified, and Pearson correlation coefficient was adopted for correlation analysis of miR-139-5p in clinical specimens. Receiver operating characteristic (ROC) curves were adopted to analyze the diagnostic value of miR-139-5p and ZEB1 for CC. The expression of genes in CC cells was changed by transfection. The proliferation, colony formation, invasion, and apoptosis of cells were determined, and the protein level of EMT markers (N-cadherin, vimentin, and E-cadherin) was also quantified. Moreover, the targeting relationship between miR-139-5p and ZEB1 was determined.

Results

Our data showed that the expression of miR-139-5p decreased greatly in CC tissues, and it also significantly decreased in the serum, while the expression of serum ZEB1 was opposite. In addition, the miR-139-5p expression in CC tissues was positively correlated with that in serum, while serum miR-139-5p was negatively correlated with serum ZEB1. The areas under the curves (AUCs) of the two for identifying CC were 0.923 and 0.890, respectively. Both up-regulation of miR-139-5p and down-regulation of ZEB1 suppressed the colony formation, proliferation, invasion, and EMT of CC cells, and intensified their apoptosis. Moreover, miR-139-5p negatively regulated the transcription of ZEB1, and down-regulation of the former could reverse the molecular regulatory effects of down-regulating ZEB1 on the above biological behaviors of CC cells.

Conclusion

The above data imply that miR-139-5p-ZEB1 axis may be the key to curbing the progression of CC.

Sex-Determining Region Y Chromosome-Related High-Mobility-Group Box 10 in Cancer: A Potential Therapeutic Target

Sex-determining region Y-related high mobility group-box 10 (SOX10), a member of the SOX family, has recently been highlighted as an essential transcriptional factor involved in developmental biology. Recently, the functionality of SOX 10 has been increasingly revealed by researchers worldwide. It has been reported that SOX10 significantly regulates the proliferation, migration, and apoptosis of tumors and is closely associated with the progression of cancer. In this review, we first introduce the basic background of the SOX family and SOX10 and then discuss the pathophysiological roles of SOX10 in cancer. Besides, we enumerate the application of SOX10 in the pathological diagnosis and therapeutic potential of cancer. Eventually, we summarize the potential directions and perspectives of SOX10 in neoplastic theranostics. The information compiled herein may assist in additional studies and increase the potential of SOX10 as a therapeutic target for cancer.

SOX5 Regulates Cell Proliferation, Apoptosis, Migration and Invasion in KSHV-Infected Cells

Kaposi's sarcoma (KS) originates from vascular endothelial cells, with KS-associated herpesvirus (KSHV) as the etiological agent. SRY-box transcription factor 5 (SOX5) plays different roles in various types of cancer, although its role in KS remains poorly understood. In this study, we identified the role of SOX5 in KS tissues and KSHV-infected cells and elucidated the molecular mechanism. Thirty-two KS patients were enrolled in this study. Measurement of SOX5 mRNA and protein levels in human KS tissues and adjacent control tissues revealed lower levels in KS tissues, with KS patients having higher SOX5 level in the early stages of the disease compared to the later stages. And SOX5 mRNA and protein was also lower in KSHV-infected cells (iSLK-219 and iSLK-BAC) than normal cells (iSLK-Puro). Additionally, SOX5 overexpression inhibited cell proliferation and promoted apoptosis and decreased KSHV-infected cell migration and invasion. Moreover, we found that SOX5 overexpression suppressed the epithelial-to-mesenchymal transition of KSHV-infected cells. These results suggest SOX5 is a suppressor factor during KS development and a potential target for KS treatment.

miR-139-5p Inhibits Lung Adenocarcinoma Cell Proliferation, Migration, and Invasion by Targeting MAD2L1

BACKGROUND

miR-139-5p is lowly expressed in various human cancers and exerts its antitumor effect through different molecular mechanisms, yet the molecular mechanism of miR-139-5p in lung adenocarcinoma (LUAD) remains to be further elucidated. The study is aimed at investigating the role and the regulatory mechanism of miR-139-5p in LUAD progression.

METHODS

Differential analysis was performed on miRNA expression data in the TCGA-LUAD dataset. qRT-PCR was employed to detect the transcription levels of miR-139-5p and MAD2L1 in LUAD cells, while western blot was carried out for the detection of MAD2L1 protein expression. CCK-8 and Transwell assays were implemented to assess LUAD cell proliferation, migration, and invasion. A dual-luciferase reporter gene assay was conducted to verify the direct targeting relationship between miR-139-5p and MAD2L1.

RESULTS

miR-139-5p was significantly downregulated in LUAD cells in comparison with that in human normal bronchial epithelial cells. Overexpressing miR-139-5p inhibited LUAD cell proliferation, migration, and invasion, while opposite results could be observed when miR-139-5p was inhibited. MAD2L1 was identified as a direct target of miR-139-5p in LUAD. Besides, the inhibitory effect of miR-139-5p overexpression on LUAD cell proliferation, migration, and invasion was attenuated by overexpressing MAD2L1.

CONCLUSION

Our study suggests that miR-139-5p is lowly expressed in LUAD cells and inhibits LUAD cell proliferation, migration, and invasion by targeted suppressing MAD2L1 expression. It is of potential significance for the prognosis and treatment of LUAD.

Hypoxia Activates SOX5/Wnt/β-Catenin Signaling by Suppressing MiR-338-3p in Gastric Cancer

MicroRNAs are known to be important in a variety of cancer types. The specific expression and roles of miR-338-3p in the context of gastric cancer, however, remains largely unknown. In this study, we found that miR-338-3p was expressed significantly lower in established/primary human gastric cancer cells than that in human gastric epithelial cells; miR-338-3p is also decreased in human gastric cancer tissues and was positively associated with the worse prognosis of patients with gastric cancer. Enforced expression of miR-338-3p could inhibit cell growth, survival, and proliferation, while inducing cell apoptosis. In addition, miR-338-3p negatively regulated SOX5 expression through directly binding to the 3′-untranslated region of SOX5, and an inverse correlation was found between miR-338-3p and SOX5 messenger RNA expression in gastric cancer tissues. Furthermore, miR-338-3p-induced inactivation of Wnt/β-catenin signaling was greatly abrogated by SOX5 upregulation. Finally, we found that hypoxic conditions were linked with reduced miR-338-3p expression in the context of gastric cancer. In conclusion, miR-338-3p acts as a tumor suppressor in gastric cancer, possibly by directly targeting SOX5 and blocking Wnt/β-catenin signaling. These findings might provide novel therapeutic targets for gastric cancer.

Role of microRNAs in the development, prognosis and therapeutic response of patients with prostate cancer

Prostate cancer is the most common cancer in males in several regions. One of the major challenges in diagnosis and treatment of this cancer is how to identify men who harbor an increased risk of having clinically significant prostate cancer and how to assess response to therapy. Biomarkers, like microRNAs (miRNAs) are one of the new diagnostic/therapeutic tools for clinicians. Finding men at high risk of significant cancer is essential as they will mostly benefit from earlier diagnosis and treatment. At the same time, it is important to reduce the number of unnecessary invasive biopsies in men without (clinically significant) cancer and miRNAs have especial application in this regard. MiRNAs can regulate expression of several genes. Up to 30 percent of protein coding genes are regulated by miRNAs. Based on this critical regulatory role, miRNAs impact cell differentiation, growth and apoptosis. Several studies have reported aberrant expression of miRNAs in different cancers including prostate cancer. miRNAs are regarded as biomarkers in this kind of cancer. Moreover, expression profiles of miRNAs can predict therapeutic response to a number of drugs such docetaxel and some natural agents such as isoflavone. Functional studies have shown that miRNAs regulate a number of critical targets such as Wnt/β-catenin, PI3K/AKT, cyclin dependent kinases, VEGF and JAK/ STAT. Therefore, several aspects of prostate cancer development are influenced by miRNAs. Finally, circulating miRNAs are promising tools for assessment of prostate cancer course and prognosis. In the current review, we summarize the results of studies which reported abnormal expression of miRNAs in prostate cancer and their role as biomarkers or therapeutic targets.

Diagnostic, prognostic, and therapeutic significance of miR-139-5p in cancers

miRNAs are a group of non-coding RNAs that have regulatory functions in post-transcriptional gene expression. These molecules play a fundamental role in cellular processes, for instance cell proliferation, apoptosis, migration, and invasion. Scientific investigations have previously established that miRNAs can either promote or suppress tumor development by mediating different signaling pathways. miR-139-5p, located on chromosome 11q13.4, has been examined extensively in cancers. Studies have demonstrated that miR-139-5p might be an attractive cancer biomarker. Herein, we will review how miR-139-5p acts in cancer diagnosis, prognosis, and therapy, as well as elucidating its major target genes and associated signaling pathways.

CircSMARCA5 Facilitates the Progression of Prostate Cancer Through miR-432/PDCD10 Axis

Background: Circular RNAs (circRNAs) have been reported to be implicated in the pathogenesis of prostate cancer (PCa). Herein, the authors explore the role and molecular mechanism of circRNA SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily a, member 5 (circSMARCA5) in PCa. Materials and Methods: The levels of circSMARCA5, SMARCA5, miR-432, and programmed cell death 10 (PDCD10) were determined by quantitative real-time polymerase chain reaction (qRT-PCR). The circular structure and stability of circSMARCA5 were validated by qRT-PCR using Oligo dT primer, transcriptional inhibitor actinomycin D, or RNase R treatment, respectively. Cell proliferation, migration, invasion, epithelial/mesenchymal transition (EMT), and glycolysis were detected by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), transwell migration and invasion assays, Western blot assay, and Glucose or Lactate Detection Kit, respectively. The target relationship between miR-432 and circSMARCA5 or PDCD10 was validated by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Western blot was performed to detect the protein expression of PDCD10 in PCa cells. Results: CircSMARCA5 was aberrantly upregulated, and was a circular and stable RNA in PCa cells. CircSMARCA5 accelerated the proliferation, metastasis, and glycolysis of PCa cells. MiR-432 was a direct target of circSMARCA5, and circSMARCA5 accelerated the development of PCa through miR-432 in PCa cells. PDCD10 was a direct target of miR-432, and PDCD10 addition reversed the inhibitory effects of miR-432 accumulation on the proliferation, metastasis, and glycolysis of PCa cells. CircSMARCA5 upregulated the expression of PDCD10 through sponging miR-432 in PCa cells. Conclusion: CircSMARCA5 deteriorated PCa through the miR-432/PDCD10 axis. CircSMARCA5/miR-432/PDCD10 axis might be an underlying therapeutic target for PCa treatment.

Breviscapine suppresses the growth and metastasis of prostate cancer through regulating PAQR4-mediated PI3K/Akt pathway

OBJECTIVES

Prostate cancer, one of the most frequently diagnosed tumors of men, leads to poor quality of life. Previous studies have shown that breviscapine (BRE) exerts therapeutic activity in malignant tumors. However, the role and mechanism of BRE exhibit an anti-tumor effect on prostate cancer are largely unknown.

METHODS

The mRNA and protein levels in prostate cancer tissues and cell lines were measured using RT-qPCR, western blot, and immunohistochemical staining, respectively. Cell proliferation, invasion, and migration in both PC3 and DU145 cells were evaluated using CCK-8 and Transwell assay. The effect of BRE on cell proliferation and metastasis by regulating the PAQR4-mediated PI3K/Akt pathway in vitro and in vivo was determined.

RESULTS

PAQR4 was significantly overexpressed in prostate cancer tissues and cell lines, which was positively correlated with poor prognosis. Knockdown of PAQR4 inhibited the proliferation, invasion, migration, and epithelial-mesenchymal transition (EMT) of both PC3 and DU145 cells. Mechanistically, BRE treatment significantly suppressed the malignant biological behavior of both prostate cancer cells by downregulating PAQR4 and blocking the PI3K/Akt pathway. In vivo experiments, BRE administration remarkably inhibited tumor growth and metastasis in a xenograft model of prostate cancer.

CONCLUSION

Our findings revealed that BRE exerts anti-tumor and anti-metastasis roles in prostate cancer by inhibiting PAQR4-mediated PI3K/Akt pathway, which provides a new therapeutic agent for prostate cancer clinical treatment.

Role of miRNAs in prostate cancer: Do we really know everything?

Many different genetic alterations, as well as complex epigenetic interactions, are the basis of the genesis and progression of prostate cancer (CaP). This is the reason why until now the molecular pathways related to development of this cancer were only partly known, and even less those that determine aggressive or indolent tumour behaviour. MicroRNAs (miRNAs) represent a class of about 22 nucleotides long, small non-coding RNAs, which are involved in gene expression regulation at the post-transcriptional level. MiRNAs play a crucial role in regulating several biological functions and preserving homeostasis, as they carry out a wide modulatory activity on various molecular signalling pathways. MiRNA genes are placed in cancer-related genomic regions or in fragile sites, and they have been proven to be involved in the main steps of carcinogenesis as oncogenes or oncosuppressors in many types of cancer, including CaP. We performed a narrative review to describe the relationship between miRNAs and the crucial steps of development and progression of CaP. The aims of this study were to improve the knowledge regarding the mechanisms underlying miRNA expression and their target genes, and to contribute to understanding the relationship between miRNA expression profiles and CaP.

Knockdown of lncRNA TUG1 Enhances Radiosensitivity of Prostate Cancer via the TUG1/miR-139-5p/SMC1A Axis

Background

Prostate cancer (PCa) is a common malignant tumor of the urinary system in males. LncRNA taurine-upregulated gene 1 (TUG1) has been verified to play a crucial role in progression and prognosis of PCa. However, the functional mechanism of TUG1 remains unclear with radiosensitivity of PCa.

Methods

Quantitative real-time PCR (qRT-PCR) was conducted to measure the transcription levels of genes. 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and flow cytometry analysis were employed to assess cell proliferation and apoptosis, respectively. Moreover, colony formation assay was used to measure colony survival. Western blot was performed to detect the relative proteins expression. The interaction among variables was predicted by online tool starbase, and then confirmed using the dual luciferase reporter assay. A xenograft mouse model was constructed to investigate the effect of TUG1 on tumor growth in vivo.

Results

The levels of lncRNA TUG1 and SMC1A were remarkably increased, while miR-139-5p was downregulated in PCa. Patients with high expression of TUG1 showed a lower survival rate and poor prognosis. Knockdown of TUG1 inhibited PCa cell proliferation and colony survival fraction, and promoted apoptosis. Downregulation of miR-139-5p reversed the effects of TUG1 deletion on proliferation, apoptosis and colony survival fraction in PCa cells treated with 4 Gy of X-ray radiation. Moreover, TUG1 sponged miR-139-5p to regulate SMC1A expression. SMC1A deletion blocked the effects of TUG1 on the progression of PCa cells treated with 4 Gy of X-ray radiation. The tumor volume and weight were illustriously reduced with radiation and TUG1 silencing in xenograft model.

Conclusion

Knockdown of lncRNA TUG1 enhanced radiosensitivity in PCa via the TUG1/miR-139-5p/SMC1A axis. It may become a promising target for PCa treatment.

miR-451a is downregulated and targets PSMB8 in prostate cancer

Abnormal expression of microRNAs (miRNAs) is frequently occurred in prostate cancer (PCa). This study was aimed to investigate the biological roles of miR-451a in PCa. Quantitative real-time PCR (qRT-PCR) and Western blot were employed to investigate the expression levels of miR-451a and proteasome (prosome, macropain) subunit, beta type, 8 (PSMB8) in PCa cell lines. Luciferase activity reporter assay was used to verify the connection between miR-451a and PSMB8. in vitro functional experiments were performed to measure the effects of miR-451a or PSMB8 on PCa cell proliferation, colony formation ability, cell invasion, and cell apoptosis. miR-451a expression was downregulated, whereas PSMB8 expression was upregulated in PCa cell lines. Luciferase activity reporter assay confirmed the direct connection between miR-451a and PSMB8. Overexpression of miR-451a inhibits PCa cell proliferation, colony formation, cell invasion and promotes cell apoptosis, while the overexpression of PSMB8 caused the opposite effects. Moreover, rescue experiments confirmed PSMB8 was a functional target of miR-451a. In conclusion, this study provides novel insights into the role of miR-451a in PCa, and the results demonstrated miR-451a could inhibit PCa progression by targeting PSMB8.

Long Noncoding RNA X-Inactive Specific Transcript Facilitates Cellular Functions in Melanoma via miR-139-5p/ROCK1 Pathway

Purpose

Although X-inactive specific transcript (XIST) is known to play a critical role in the pathogenesis of melanoma, the mechanisms through which this remains unclear.

Methods

RNAseq, immunohistochemistry, and qRT-PCR were used to identify the levels of XIST, miR-139-5p, and Rho-Associated Coiled-Coil Containing Protein Kinase-1 (ROCK1) in melanoma tissues and cells. A subcellular fractionation assay was used to determine the location of XIST. CCK-8 and colony formation assays were used to evaluate cellular proliferation. Cell migration and wound healing assays were used to detect the effects on cell migration. RNA pull-down was used to confirm the interaction between XIST and miR-139-5p. Besides, the xenograft tumor experiment was performed to further verify the roles of XIST in melanoma.

Results

In this study, an increased level of XIST was revealed in melanoma tissues and cells, which was associated with higher TNM stage and positive lymph node metastasis. XIST was found to function as a “molecular sponge” of miR-139-5p to facilitate cellular functions. Moreover, these consequences could be partially reversed by inhibition of miR-139-5p. MiR-139-5p was found to target ROCK1 directly, leading to suppression of ROCK1 expression; this effect could be partially reversed by inhibiting XIST expression. Furthermore, the deletion of ROCK1 induced anti-oncogenic effects similar to those seen with knockout of XIST. Upregulation of miR-139-5p and knockdown of XIST could inhibit cell functions in melanoma.

Conclusion

Our findings suggested that the lncRNA XIST facilitates cellular functions in melanoma via the miR-139-5p/ROCK1 pathway.

CircRNA CDR1as knockdown inhibits progression of non-small-cell lung cancer by regulating miR-219a-5p/SOX5 axis

BACKGROUND

Circular RNAs (circRNAs) participate in the development of human cancers by regulating multiple cell processes. CircRNA antisense to the cerebellar degeneration-related protein 1 transcript (circCDR1as) expression is dysregulated in many cancers, including non-small-cell lung cancer (NSCLC). However, the mechanism by which circCDR1as mediates the development of NSCLC remains unknown.

METHODS

A total of 30 paired cancer and normal tissues were collected from patients with NSCLC. The expression levels of circCDR1as, microRNA (miR)-219a-5p and Sex determining region Y-box protein 5 (SOX5) were measured in tissues or cells by quantitative real-time polymerase chain reaction or western blot. Cell viability, apoptosis, migration and invasion were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide, colony formation, flow cytometry and transwell assays, respectively. The target relationship between miR-219a-5p and circCDR1as or SOX5 was validated by dual-luciferase reporter assay.

RESULTS

CircCDR1as expression was elevated in NSCLC tissues and cells in comparison to the matched controls. Interference of circCDR1as led to obvious inhibition of cell viability, migration and invasion and increase of apoptosis in NSCLC cells. MiR-219a-5p acted as a target of circCDR1as and miR-219a-5p downregulation attenuated the regulatory effect of circCDR1as silencing on NSCLC progression. Moreover, miR-219a-5p targeted SOX5 to repress the progression of NSCLC in vitro. Besides, circCDR1as knockdown reduced the expression of SOX5 by increasing miR-219a-5p level.

CONCLUSION

Knockdown of circCDR1as inhibited the progression of NSCLC by decreasing cell viability, migration and invasion and increasing apoptosis by upregulating miR-219a-5p and downregulating SOX5.

miR-139 Controls Viability Of Ovarian Cancer Cells Through Apoptosis Induction And Exosome Shedding Inhibition By Targeting ATP7A

Background

Emerging proof suggests that microRNA (miRNA) malfunction is correlated to the generation and development of multiple malignancies. It has been proven that miRNA (miR)-139 represses a variety of malignancies. However, the understanding of its impact on ovarian cancer (OC) is insufficient. We aimed to investigate the expression and function of miR-139 in OC.

Methods

The expression of mir-139 was detected and recorded, and the relationship of mir-139 remaining OC cells was explored. At the same time, we studied the correlation between ATP7A and mir-139 by the luciferase reporter test, Western blot, and quantitative real-time reverse transcription PCR.

Results

The expression of miR-139 was remarkably downregulated in OC specimens. Furthermore, excessive miR-139 expression noticeably inhibited the migration, colony generation, proliferation, and invasion of OC cells. In addition, excessive miR-139 expression remarkably repressed the death and the expression of proteins related to cell death in OC cells, as well as inhibited the shedding of exosomes. According to the luciferase reporter test, Western blot, and quantitative real-time reverse transcription PCR, miR-139 directly targeted ATP7A. Furthermore, the expression of ATP7A was found to be negatively related to miR-139 levels in OC specimens. It was revealed via a rescue experiment that excessive ATP7A expression counteracted the repressive effect of miR-139 in OC cells.

Conclusion

It was revealed via an in vivo study that miR-139 remarkably inhibited the growth of malignancies by downregulating ATP7A in nude mice. miR-139 represses the development of malignancies in OC by directly targeting ATP7A, offering an innovative approach for molecular therapy of OC.

Increased expression of miR-601 is associated with poor prognosis and tumor progression of gastric cancer

Background

MicroRNAs (miRNAs) have been considered to participate in many tumorigenesis, including gastric cancer (GC). Abnormal expression of miR-601 has been reported in GC, but its role is not clear. The goal of this study is to explore the expression patterns, clinical value and functional role of miR-601 in GC.

Methods

Quantitative real-time polymerase chain reaction (qRT-PCR) was conducted to evaluate the expression level of miR-601. The association between miR-601 expression and overall survival was estimated by the Kaplan-Meier survival method. The significance of different variables with respect to survival was analyzed by using the Cox regression assay. Cell experiments were applied to investigate the functional role of miR-601 in GC.

Results

We found that miR-601 was significantly up-regulated in GC tissues and cells compared with the controls (all P < 0.01). The levels of miR-601 expression were significantly associated with TNM stage, lymph node metastasis, lymphatic invasion, and distant metastasis (all P < 0.05). Kaplan-Meier survival analysis showed that patients in the high miR-601 expression group had poor overall survival (log-rank P = 0.001). Moreover, we confirmed that miR-601, TNM stage, and distant metastasis were independent prognostic factors for GC patients. Overexpression of miR-601 in AGS and SGC-7901 cells by miR-601 mimic transfection significantly promoted the cell proliferation, migration, and invasion (P < 0.05).

Conclusions

The expression level of miR-601 is dramatically up-regulated in GC. The overexpression of miR-601 promotes the tumor progression of GC, and may be a novel prognostic factor for poor survival in GC patients.

miR-139-5p functions as a tumor suppressor in cervical cancer by targeting TCF4 and inhibiting Wnt/β-catenin signaling

Objectives

Dysregulation of microRNAs (miRNAs) has been recognized as a crucial biological event in the development of cervical cancer (CC). miR-139-5p was identified as a significant tumor suppressor in multiple human cancers, leaving its roles and mechanisms in CC absolutely unclear. We aimed to investigate the implication of miR-139-5p in CC progression.

Methods

miR-139-5p expression in 40 paired CC tissues and several cell lines was determined by qRT-PCR firstly. The implications of miR-139-5p in CC cell proliferation and migration were revealed by CCK-8, EdU and transwell assays, respectively. The mechanism underlying the tumor-suppressing roles of miR-139-5p in CC was investigated sequentially by dual luciferase, qRT-PCR, and Western blot analysis. The expression of transcription factor 4 (TCF4), the validated target of miR-139-5p from our experiments, was finally detected by qRT-PCR and immunohistochemistry in CC tissues, and its expression correlates with miR-139-5p was explored.

Results

We found that miR-139-5p expression was frequently decreased in CC tissues and cell lines, and its lower level was associated with positive lymph node metastasis. Cellular assays proved the significant tumor-suppressing roles of miR-139-5p by inhibiting CC cell proliferation and migration, and markedly blocking Wnt/β-catenin signaling. Since bioinformatics analysis indicated TCF4 as a novel target of miR-139-5p, our mechanistic studies validated this, and confirmed that TCF4 restoration could attenuate the tumor inhibitory activities of miR-139-5p in CC progression, and recover the normal Wnt/β-catenin signaling.

Conclusion

Our data collectively demonstrated that miR-139-5p was a vital tumor suppressor in CC pathogenesis via targeting TCF4 thereby inhibiting Wnt/β-catenin signaling. The miR-139-5p/TCF4 axis may serve as a promising target for CC therapy.

LncRNA SNHG3 promotes clear cell renal cell carcinoma proliferation and migration by upregulating TOP2A

LncRNA plays a vital role in many diseases, and abnormal expression of LncRNA has been reported in many types of tumors. In this study, we analyzed the available public TCGA and GEO databases, and found that the expression of SNHG3 was increased in clear cell renal cell carcinoma (ccRCC), which was positively correlated with many clinicopathological parameters, and the higher expression of SNHG3 predicted worse clinical prognosis. Functional experiments indicated that knockdown of SNHG3 could significantly inhibit the proliferation and metastasis of ccRCC in vitro and in vivo. Subsequently, through luciferase reporter assays, qPCR and rescue experiments, it was found that SNHG3 could bind to miR-139-5p, thereby up-regulating the expression of its target gene TOP2A, and play a role in promoting tumor progression in ccRCC. The correlation analysis showed that there was a significant positive correlation between the expression of SNHG3 and TOP2A, and both of them were significantly negative correlated with the expression of miR-139-5p. Our work suggested that the SNHG3/miR-139-5p/TOP2A axis plays an important role in the proliferation and metastasis of ccRCC, and was expected to be a new biomarker for diagnosis, prognosis and a target for treatment of ccRCC.

Emerging Role of SOX Proteins in Breast Cancer Development and Maintenance

The SOX genes encode a family of more than 20 transcription factors that are critical regulators of embryogenesis and developmental processes and, when aberrantly expressed, have been shown to contribute to tumor development and progression in both an oncogenic and tumor suppressive role. Increasing evidence demonstrates that the SOX proteins play essential roles in multiple cellular processes that mediate or contribute to oncogenic transformation and tumor progression. In the context of breast cancer, SOX proteins function both as oncogenes and tumor suppressors and have been shown to be associated with tumor stage and grade and poor prognosis. Experimental evidence demonstrates that a subset of SOX proteins regulate critical aspects of breast cancer biology including cancer stemness and multiple signaling pathways leading to altered cell proliferation, survival, and tumor development; EMT, cell migration and metastasis; as well as other tumor associated characteristics. This review will summarize the role of SOX family members as important mediators of tumorigenesis in breast cancer, with an emphasis on the triple negative or basal-like subtype of breast cancer, as well as examine the therapeutic potential of these genes and their downstream targets.