MiR-501-3p functions as a tumor suppressor in non-small cell lung cancer by downregulating RAP1A

Molecular mechanisms underlying the regulation of tumour suppressor genes in lung cancer

Tumour suppressor genes play a cardinal role in the development of a large array of human cancers, including lung cancer, which is one of the most frequently diagnosed cancers worldwide. Therefore, extensive studies have been committed to deciphering the underlying mechanisms of alterations of tumour suppressor genes in governing tumourigenesis, as well as resistance to cancer therapies. In spite of the encouraging clinical outcomes demonstrated by lung cancer patients on initial treatment, the subsequent unresponsiveness to first-line treatments manifested by virtually all the patients is inherently a contentious issue. In light of the aforementioned concerns, this review compiles the current knowledge on the molecular mechanisms of some of the tumour suppressor genes implicated in lung cancer that are either frequently mutated and/or are located on the chromosomal arms having high LOH rates (1p, 3p, 9p, 10q, 13q, and 17p). Our study identifies specific genomic loci prone to LOH, revealing a recurrent pattern in lung cancer cases. These loci, including 3p14.2 (FHIT), 9p21.3 (p16INK4a), 10q23 (PTEN), 17p13 (TP53), exhibit a higher susceptibility to LOH due to environmental factors such as exposure to DNA-damaging agents (carcinogens in cigarette smoke) and genetic factors such as chromosomal instability, genetic mutations, DNA replication errors, and genetic predisposition. Furthermore, this review summarizes the current treatment landscape and advancements for lung cancers, including the challenges and endeavours to overcome it. This review envisages inspired researchers to embark on a journey of discovery to add to the list of what was known in hopes of prompting the development of effective therapeutic strategies for lung cancer.

Identification of miRNAs that target Fcγ receptor-mediated phagocytosis during macrophage activation syndrome

Macrophage activation syndrome (MAS) is a life-threatening complication of systemic juvenile arthritis, accompanied by cytokine storm and hemophagocytosis. In addition, COVID-19-related hyperinflammation shares clinical features of MAS. Mechanisms that activate macrophages in MAS remain unclear. Here, we identify the role of miRNA in increased phagocytosis and interleukin-12 (IL-12) production by macrophages in a murine model of MAS. MAS significantly increased F4/80+ macrophages and phagocytosis in the mouse liver. Gene expression profile revealed the induction of Fcγ receptor-mediated phagocytosis (FGRP) and IL-12 production in the liver. Phagocytosis pathways such as High-affinity IgE receptor is known as Fc epsilon RI -signaling and pattern recognition receptors involved in the recognition of bacteria and viruses and phagosome formation were also significantly upregulated. In MAS, miR-136-5p and miR-501-3p targeted and caused increased expression of Fcgr3, Fcgr4, and Fcgr1 genes in FGRP pathway and consequent increase in phagocytosis by macrophages, whereas miR-129-1-3p and miR-150-3p targeted and induced Il-12. Transcriptome analysis of patients with MAS revealed the upregulation of FGRP and FCGR gene expression. A target analysis of gene expression data from a patient with MAS discovered that miR-136-5p targets FCGR2A and FCGR3A/3B, the human orthologs of mouse Fcgr3 and Fcgr4, and miR-501-3p targets FCGR1A, the human ortholog of mouse Fcgr1. Together, we demonstrate the novel role of miRNAs during MAS pathogenesis, thereby suggesting miRNA mimic-based therapy to control the hyperactivation of macrophages in patients with MAS as well as use overexpression of FCGR genes as a marker for MAS classification.

[Plasma miRNA expression in patients with genetically confirmed multiple endocrine neoplasia type 1 syndrome and its phenocopies]

BACKGROUND

MEN-1 is a rare autosomal dominant disease caused by mutations in MEN1 gene encoding the menin protein. This syndrome is characterized by the occurrence of parathyroid tumors, gastroenteropancreatic neuroendocrine tumors, pituitary adenomas, as well as other endocrine and non-endocrine tumors. If a patient with the MEN-1 phenotype carry no mutations in the MEN1 gene, the condition considers a phenocopy of syndrome (phMEN1). The possible cause of this changes could be changes in epigenetic regulation, particularly in microRNA expression that might affect menin signaling pathways.

AIM

to identify differently expressed circulating miRNAs in plasma in patients with genetically confirmed MEN-1 syndrome, its phenocopies and healthy controls.

MATERIALS AND METHODS

single-center, case-control study was conducted. We assessed plasma microRNA expression in patients with genetically confirmed MEN-1 (gMEN1), phMEN1 and healthy controls. Morning plasma samples were collected from fasting patients and stored at -80°C. Total RNA isolation was performed using miRNeasy Mini Kit with QIAcube. The libraries were prepared by the QIAseq miRNA Library Kit following the manufacturer. Circulating miRNA sequencing was done on Illumina NextSeq 500 (Illumina). Subsequent data processing was performed using the DESeq2 bioinformatics algorithm.

RESULTS

we enrolled 21 consecutive patients with gMEN1 and 11 patients with phMEN1, along with 12 gender matched controls. Median age of gMEN1 was 38,0 [34,0; 41,0]; in phMEN1 - 59,0 [51,0; 60,0]; control - 59,5 [51,5; 62,5]. The gMEN1 group differed in age (p<0.01) but not gender (р=0.739) or BMI (р=0.116) compared to phMEN1 and controls group, the last two groups did not differ by these parameters (p>0.05). 25 microRNA were differently expressed in groups gMEN1 and phMEN1 (21 upregulated microRNAs, 4 - downregulated). Comparison of samples from the phMEN-1 group and relatively healthy controls revealed 10 differently expressed microRNAs: 5 - upregulated; 5 - downregulated. In the gMEN-1 and control groups, 26 differently expressed microRNAs were found: 24 - upregulated; 2 - downregulated. The miRNAs most differing in expression among the groups were selected for further validation by RT-qPCR (in the groups of gMEN1 vs phMEN1 - miR-3613-5p, miR-335-5p, miR-32-5p, miR-425-3p, miR-25-5p, miR-576-5p, miR-215-5p, miR-30a-3p, miR-141-3p, miR-760, miR-501-3p; gMEN1 vs control - miR-1976, miR-144-5p miR-532-3p, miR-375; as well as in phMEN1 vs control - miR-944, miR-191-5p, miR-98-5p).

CONCLUSION

In a pilot study, we detected microRNAs that may be expressed differently between patients with gMEN-1 and phMEN-1. The results need to be validated using different measurement method with larger sample size.

MicroRNA, miR-501 regulate the V(D)J recombination in B cells

The stringent regulation of RAGs (Recombination activating genes), the site-specific endonuclease responsible for V(D)J recombination, is important to prevent genomic rearrangements and chromosomal translocations in lymphoid cells. In the present study, we identify a microRNA, miR-501, which can regulate the expression of RAG1 in lymphoid cells. Overexpression of the pre-miRNA construct led to the generation of mature miRNAs and a concomitant reduction in RAG1 expression, whereas inhibition using anti-miRs resulted in its enhanced expression. The direct interaction of the 3'UTR of miR-501 with RAG1 was confirmed by the reporter assay. Importantly, overexpression of miRNAs led to inhibition of V(D)J recombination in B cells, revealing their impact on the physiological function of RAGs. Of interest is the inverse correlation observed for miR-501 with RAG1 in various leukemia patients and lymphoid cell lines, suggesting its possible use in cancer therapy. Thus, our results reveal the regulation of RAG1 by miR-501-3p in B cells and thus V(D)J recombination and its possible implications on immunoglobulin leukemogenesis.

N6-methyladenosine (m6A) methylation in kidney diseases: Mechanisms and therapeutic potential

The N6-methyladenosine (m6A) modification is regulated by methylases, commonly referred to as "writers," and demethylases, known as "erasers," leading to a dynamic and reversible process. Changes in m6A levels have been implicated in a wide range of cellular processes, including nuclear RNA export, mRNA metabolism, protein translation, and RNA splicing, establishing a strong correlation with various diseases. Both physiologically and pathologically, m6A methylation plays a critical role in the initiation and progression of kidney disease. The methylation of m6A may also facilitate the early diagnosis and treatment of kidney diseases, according to accumulating research. This review aims to provide a comprehensive overview of the potential role and mechanism of m6A methylation in kidney diseases, as well as its potential application in the treatment of such diseases. There will be a thorough examination of m6A methylation mechanisms, paying particular attention to the interplay between m6A writers, m6A erasers, and m6A readers. Furthermore, this paper will elucidate the interplay between various kidney diseases and m6A methylation, summarize the expression patterns of m6A in pathological kidney tissues, and discuss the potential therapeutic benefits of targeting m6A in the context of kidney diseases.

SOX9 promotes the invasion and migration of lung adenocarcinoma cells by activating the RAP1 signaling pathway

OBJECTIVE

SOX9 has been shown to be related to the metastasis of various cancers. Recently, it has been reported that SOX9 plays a regulatory role in lung adenocarcinoma (LUAD) cell metastasis, but the specific mechanism remains to be explored. Therefore, the objective of this study was to observe the effect and mechanism of SOX9 on the invasion and migration of LUAD cells.

METHODS

RT-qPCR was applied to observe the expression of SOX9 and RAP1 in tumor tissues and corresponding normal lung tissues collected from LUAD patients. Co-immunoprecipitation and Pearson correlation to analyze the expression correlation of SOX9 with RAP1. To observe the role of SOX9, the invasion and migration levels of LUAD A549 cells in each group were observed by Transwell invasion assay and Scratch migration assay after knocking down or overexpressing SOX9. Besides, the expression levels of RAP1 pathway-related proteins (RAP1, RAP1GAP and RasGRP33) were observed by RT-qCPR or western blot. Subsequently, RAP1 was overexpressed and SOX9 was knocked down in A549 cells, and then the cell invasion/migration level and RAP1 pathway activity were assessed.

RESULTS

The expression levels of SOX9 and RAP1 in tumor tissues and A549 cells of LUAD patients were significantly increased and positively correlated. Overexpression of SOX9 or RAP1 alone in A549 cells enhanced the invasion and migration ability of cells, as well as up-regulated the expression levels of RAP1, RAP1GAP and RasGRP33. However, knocking down SOX9 decreased cell invasion and migration levels and weakened the activity of RAP1 pathway. Notably, overexpressing RAP1 while knocking down SOX9 significantly activated RAP1 pathway and promoted cell invasion and migration.

CONCLUSION

Overexpression of SOX9 in LUAD can significantly activate the RAP1 signaling pathway and promote cell invasion and migration.

Anesthetic propofol enhances cisplatin-sensitivity of non-small cell lung cancer cells through N6-methyladenosine-dependently regulating the miR-486-5p/RAP1-NF-κB axis

BACKGROUND

Drug resistance is a considerable challenge for chemotherapy in non-small cell lung cancer (NSCLC). Propofol, a commonly used intravenous anesthetics, has been reported to suppress the malignancy of various cancers. However, the effects of propofol on cisplatin (DDP) sensitivity in NSCLC and its molecular mechanisms have not been clearly clarified yet, and the present study aimed to resolve this problem.

METHODS

NSCLC cells were co-treated with propofol and DDP, Cell Counting kit-8 assay, colony formation assay and flow cytometry were conducted to test the role of propofol in regulating DDP-resistance in NSCLC. Next, through conducting quantitative real-time polymerase chain reaction, dual-luciferase gene reporter system and western blot, the responsible molecular axis in propofol regulating the DDP sensitivity in NSCLC was uncovered, and the function verification experiments were performed by transfection with the inhibitors or small interfering RNAs of those molecules.

RESULTS

Propofol suppressed cell viability, colony formation ability, tumorigenesis, and promoted cell apoptosis to enhance DDP-sensitivity in NSCLC in vitro and in vivo. Propofol increased miR-486-5p level in NSCLC cells and xenograft tumors tissues in a N6-methyladenosine (m6A)-dependent manner, thus inactivating the Ras-associated protein1 (RAP1)-NF-kappaB (NF-κB) axis. Propofol regulated the miR-486-5p/RAP1-NF-κB axis to improve DDP-sensitivity in NSCLC.

CONCLUSIONS

Taken together, this study firstly investigates the detailed molecular mechanisms by which propofol enhanced DDP-sensitivity in NSCLC cells, and a novel m6A-dependent miR-486-5p/RAP1-NF-κB axis is identified to be closely associated with the process.

MicroRNA-501-3p targeting TM4SF1 facilitates tumor-related behaviors of gastric cancer cells via EMT signaling pathway

BACKGROUND

Increasing evidence shows that Transmembrane 4 L6 family member 1(TM4SF1) exerts a critical role in mediating the progression of various tumors. Nevertheless, the exact mechanism of TM4SF1 in gastric cancer (GC) remains unclear.

METHODS

Bioinformatics analysis was utilized to analyze TM4SF1 expression in GC tissues. Also, MiRWalk and starBase databases were used to predict the upstream microRNAs which could regulate TM4SF1 expression. Gene set enrichment analysis (GSEA) for TM4SF1 was conducted to screen the potentially involved pathways. Dysregulation of microRNA-501-3p/TM4SF1 was implemented to investigate the regulatory roles of these genes in GC. qRT-PCR and western blot were employed to measure the expression changes of microRNA-501-3p, TM4SF1, and epithelial-mesenchymal transition (EMT) signaling pathway-associated proteins. CCK-8, colony formation, and transwell assays were introduced to examine the biological functions of GC cell lines.

RESULTS

TM4SF1 presented a significantly low level in mRNA and protein in GC cells. MicroRNA-501-3p could target TM4SF1 and reduce its expression. Cell function experiments revealed that microRNA-501-3p facilitated cell proliferation, migration, and invasion, while inhibiting cell apoptosis in GC by targeting TM4SF1. EMT-associated proteins were altered by changing microRNA-501-3p/TM4SF1 axis.

CONCLUSION

MicroRNA-501-3p regulated EMT signaling pathway by down-regulating TM4SF1 expression and therefore facilitated the malignant progression of GC, which may provide a new potential therapeutic target for the treatment of GC patients.

MicroRNA Alterations Induced in Human Skin by Diesel Fumes, Ozone, and UV Radiation

Epigenetic alterations are a driving force of the carcinogenesis process. MicroRNAs play a role in silencing mutated oncogenes, thus defending the cell against the adverse consequences of genotoxic damages induced by environmental pollutants. These processes have been well investigated in lungs; however, although skin is directly exposed to a great variety of environmental pollutants, more research is needed to better understand the effect on cutaneous tissue. Therefore, we investigated microRNA alteration in human skin biopsies exposed to diesel fumes, ozone, and UV light for over 24 h of exposure. UV and ozone-induced microRNA alteration right after exposure, while the peak of their deregulations induced by diesel fumes was reached only at the end of the 24 h. Diesel fumes mainly altered microRNAs involved in the carcinogenesis process, ozone in apoptosis, and UV in DNA repair. Accordingly, each tested pollutant induced a specific pattern of microRNA alteration in skin related to the intrinsic mechanisms activated by the specific pollutant. These alterations, over a short time basis, reflect adaptive events aimed at defending the tissue against damages. Conversely, whenever environmental exposure lasts for a long time, the irreversible alteration of the microRNA machinery results in epigenetic damage contributing to the pathogenesis of inflammation, dysplasia, and cancer induced by environmental pollutants.

MiR-769-5p, Which Targets HDGF, Inhibits Cell Proliferation and Invasion in Nonsmall Cell Lung Cancer

MiR-769-5p regulates tumor correlative genes, which plays a critical role in the progression of various types of tumor. However, the precise regulatory mechanism of miR-769-5p on nonsmall cell lung cancer (NSCLC) is unknown. This study was to discover the role and underlying mechanisms of miR-769-5p in NSCLC. MiR-769-5p expression was shown to be reduced, according to our findings. MiR-769-5p overexpression inhibited NSCLC cell proliferation while promoting NSCLC cell apoptosis. Furthermore, NSCLC cell migration and invasion were reduced when miR-769-5p was overexpressed. Furthermore, HDGF was confirmed as a miR-769-5p target gene that was negatively regulated by miR-769-5p. Furthermore, more research revealed that HDGF overexpression reduced the inhibitory effect of miR-769-5p on NSCLC cell biofunction. Finally, miR-769-5p inhibited NSCLC cell proliferation and invasion by targeting HDGF, indicating that NSCLC could benefit from miR-769-5p as a diagnostic and prognostic biomarker.

MicroRNA-501-3p inhibits the proliferation of kidney cancer cells by targeting WTAP

BACKGROUND

Emerging evidence suggests that miR-501-3p plays an important role in the pathogenesis and progression of various carcinomas. However, its role and underlying mechanisms in renal cell carcinoma (RCC) remain to be elucidated.

METHODS

Quantitative RT-PCR, western blot, and bioinformatics methods were used to evaluate the expression of miR-501-3p and Wilms' tumor 1-associating protein (WTAP) in RCC cell lines and clinical tissues. The effects of miR-501-3p on the proliferation of RCC cells were investigated using flow cytometric, colony formation, and CCK8 assays. The target gene of miR-501-3p was confirmed by western blotting, qRT-PCR, and dual-luciferase reporter assays. The levels of RNA methylation with N6-methyladenosine (m⁶ A) following miR-501-3p overexpression or knockdown of its target gene were quantified using a dot-blot assay.

RESULTS

miR-501-3p expression was significantly downregulated in human RCC cell lines and tissues. In contrast, its overexpression markedly inhibited cancer cell proliferation in vitro by inducing G1 phase arrest. Moreover, WTAP was verified as a direct target gene of miR-501-3p. WTAP gene knockdown alone efficiently produced the same cancer-inhibiting effects as miR-501-3p overexpression, with the level of m⁶ A in RCC cells being decreased under both scenarios. The intermolecular interaction between miR-501-3p and WTAP was further substantiated by rescue experiments.

CONCLUSION

RCC progression is regulated via the miR-501-3p/WTAP/CDK2 axis and is inhibited by the overexpression of miR-501-3p.

Expression, Clinical Significance, and Prospective Pathway Signaling of miR-501-3p in Ovarian Cancer Based on Database and Informatics Analysis

Background

The present study aims to explore the expression, clinical significance, and prospective pathway signaling of miR-501-3p in ovarian cancer (OC) based on database and informatics analysis.

Methods

Kruskal–Wallis test, Wilcoxon sign-rank test, and logistic regression were used to evaluate the relationship between clinical features and miR-501-3p expression. Kaplan–Meier survival curve analysis was used to explore the relationship between miR-501-3p expression and the prognosis of OC patients. The miRNA targets were obtained from databases TargetScan, miRanda, TarBase, miRTarBase, miR2Disease, miRecords, and miRWalk. GO and KEGG analyses were used to analyze the significant involvement of miR-501-3p target genes in function.

Results

The low miR-501-3p expression in OC was significantly associated with histologic grade (P=0.015). Low miR-501-3p expression predicted a poorer overall survival (HR: 0.77; 95% CI: 0.61–0.96; P=0.02) and disease-specific survival (HR: 0.77; 95% CI: 0.61–0.99; P=0.038). GO and KEGG analyses demonstrated that miR-501-3p might participate in the development of OC by pathways including one carbon pool by folate, protein digestion and absorption, cell cycle, kaposi sarcoma-associated herpesvirus infection, and viral carcinogenesis.

Conclusions

Low miR-501-3p expression is significantly associated with poor survival in OC patients. It may be a promising prognostic biomarker for OC patients.

MiR-501 promotes tumor proliferation and metastasis by targeting HOXD10 in endometrial cancer

Background

Several studies have shown the crucial role of miR-501 in regulating cellular pathology in various cancers. However, the function and expression of miR-501 in endometrial cancer (EC) remain obscure.

Methods

The expression of miR-501 was determined using quantitative real-time PCR. MTT assay, colony formation assay and cell cycle analysis were used to evaluate the proliferation ability. Migration and invasion were assessed using transwell assay. Tumor formation in nude mice was used to observe the effects of miR-501 on cell proliferation and migration in vivo. Luciferase assay, quantitative real-time PCR and western blot were applied to determine that HOXD10 was the target gene of miR-501.

Results

In this study, we observed significantly up-regulated expression of miR-501 in endometrial cancer, which correlated with higher pelvic lymph node metastasis and shorter overall survival in high-grade endometrial cancer. High expression of miR-501 was also found in the copy-number-high group than other groups. Moreover, in vitro and in vivo assay showed that overexpression of miR-501 can promote proliferation and metastasis. Mechanistically, we found that miR-501 promotes tumor progression by directly targeting HOXD10. Further study also indicated that miR-501 overexpression can activate the AKT/mTOR pathway.

Conclusions

MiR-501, which functions as an oncomir in endometrial cancer, might be a potential therapeutic target in high grade endometrial cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s11658-021-00268-7.

Discovery and validation of hsa_circ_0001953 as a potential biomarker for proliferative diabetic retinopathy in human blood

PURPOSE

This study aimed to determine whether circular RNAs (circRNAs) in whole blood could be served as novel non-invasive biomarkers for proliferative diabetic retinopathy (PDR).

METHODS

This retrospective cross-sectional study comprised 34 healthy participants, 34 PDR patients and 34 non-proliferative DR (NPDR) patients. High-throughput whole transcriptome sequencing was performed to explore the expression profile of circRNAs in the whole blood, and the candidate circRNAs were validated by quantitative real-time polymerase chain reaction (qRT-PCR). Receiver operating characteristic (ROC) analysis evaluated the ability of these candidate circRNAs in discriminating PDR patients from NPDR patients and healthy subjects. Finally, the networks of circRNA-miRNA-mRNA based on the candidate circRNAs were constructed.

RESULTS

Using sequencing and qRT-PCR, hsa_circ_0001953 was found to be elevated in PDR patients in contrast with the other two groups. Statistical analysis showed that the expression levels of hsa_circ_0001953 in PDR patients were positively related to the duration of diabetes and HbAc1. Receiver operating characteristic (ROC) curve analysis revealed that hsa_circ_0001953 was associated with a high diagnostic accuracy in discriminating PDR patients from NPDR patients and healthy controls, resulting in an area under the curve (AUC) of 0.87 and 0.92, respectively. The circRNA-miRNA-target gene networks for hsa_circ_0001953 showed that hsa_circ_0001953 could interact with dozens of miRNAs and some targeted mRNAs have been potentially involved in the pathogenesis of diabetes.

CONCLUSION

The present findings indicate that hsa_circ_0001953 in the whole blood may serve as a novel diagnostic biomarker and potential therapeutic target for PDR.

M2 macrophages-derived exosomal microRNA-501-3p promotes the progression of lung cancer via targeting WD repeat domain 82

Background

Exosomes are known to transmit microRNAs (miRNAs) to affect cancer progression, while the role of M2 macrophages-derived exosomes (M2 exosomes) conveying miR-501-3p in lung cancer (LC) remains unknown. We aim to explore the role of exosomal miR-501-3p in LC development via targeting WD repeat domain 82 (WDR82).

Methods

Lung cancer tissue and normal tissue specimens were collected, in which tumor-associated macrophages (TAM) were measured by immunohistochemistry. M2 macrophages were induced and treated with altered miR-501-3p, and then the exosomes were extracted and identified. MiR-501-3p and WDR82 expression in LC tissues and cell liens was determined. The predictive role of miR-501-3p in prognosis of LC patients was assessed, and the proliferation, colony formation ability, invasion, migration and apoptosis of the LC cells were determined. Targeting relationship between miR-501-3p and WDR82 was confirmed.

Results

TAM level was elevated in lung cancer tissues. MiR-501-3p was upregulated while WDR82 was downregulated in LC tissues and cell lines, and the M2 exosomes further upregulated miR-501-3p. M2 exosomes and exosomal miR-501-3p promoted LC cell growth. MiR-501-3p inhibition reversed the effect of M2 exosomes on LC cells. WDR82 was confirmed as a target gene of miR-501-3p.

Conclusion

M2 macrophages-derived exosomal miR-501-3p promotes the progression of LC via downregulating WDR82.

MiR-501-3p promotes osteosarcoma cell proliferation, migration and invasion by targeting BCL7A

Increasing numbers of evidences have demonstrated that microRNAs (miRNAs) play an important role in osteosarcoma (OS) cell functions. MiR-501-3p has been reported to play an important role in several types of tumors, including prostate cancer and hepatocellular carcinoma. However, the biological function and potential mechanism of miR-501-3p in OS have not been well investigated until now. Here, we analyzed the expression of miR-501-3p in OS tissues and cell lines and its clinical significance in OS patients. Quantitative reverse transcription PCR showed miR-501-3p was significantly up-regulated in OS tissues and cell lines. Up-regulated miR-501-3p expression was associated with TNM stage, distal metastasis and worse prognosis in OS patients. MiR-501-3p knockdown and overexpression were achieved by miR-501-3p inhibitor and mimics transfection, respectively. CCK-8, colony formation and transwell assays showed that miR-501-3p knockdown in U2OS and Saos-2 cells suppressed, while miR-501-3p overexpression in Saos-2 cells promoted cell proliferation, migration and invasion. Moreover, luciferase reporter assay supporting BCL7A was a target of miR-501-3p and its expression was increased by miR-501-3p inhibitor, but inhibited by miR-501-3p mimics. By performing rescue experiments, we further demonstrated that BCL7A was a downstream functional regulator involved in miR-501-3p promoting OS cell functions. In summary, our findings suggest that miR-501-3p targets BCL7A may provide novel therapeutic targets for the treatment of OS.

Circ-ZNF609 Accelerates the Radioresistance of Prostate Cancer Cells by Promoting the Glycolytic Metabolism Through miR-501-3p/HK2 Axis

Background

The development of radioresistance remains the obstacle for prostate cancer (PCa) treatment. Here, we explored the role and potential mechanism of circular RNA zinc finger protein 609 (circ-ZNF609) in the radioresistance of PCa cells.

Materials and Methods

Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of circ-ZNF609, microRNA-501-3p (miR-501-3p) and hexokinase 2 (HK2) messenger RNA (mRNA). The viability, apoptosis, metastasis and radioresistance of PCa cells were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometry, transwell assays and colony formation assay. The glycolytic rate was assessed through measuring the glucose consumption and lactate production using fluorescence-based glucose and lactate assay kits. The target interaction between miR-501-3p and circ-ZNF609 or HK2 was predicted by StarBase software and confirmed by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. The protein level of HK2 was detected by Western blot assay. In vivo tumor growth assay was used to explore the role of circ-ZNF609 in the radioresistance of PCa in vivo.

Results

Circ-ZNF609 was abnormally up-regulated in PCa tissues and cell lines. Circ-ZNF609 silencing hampered the viability, metastasis, radioresistance and promoted the apoptosis through suppressing cell glycolysis. MiR-501-3p was a direct target of circ-ZNF609, and si-circ-ZNF609-induced influence in PCa cells was partly alleviated by the addition of anti-miR-501-3p. MiR-501-3p functioned through directly interacting with and down-regulating HK2. HK2 was modulated by circ-ZNF609/miR-501-3p axis in PCa cells. Circ-ZNF609 silencing enhanced the radiosensitivity of PCa cells in vivo.

Conclusion

Circ-ZNF609 promoted the progression and radioresistance of PCa cells through accelerating the glycolysis via miR-501-3p/HK2 axis, providing promising targets for improving the prognosis of PCa patients.