Expression of miR-224-5p is associated with the original cisplatin resistance of ovarian papillary serous carcinoma

Ovarian Cancer—Insights into Platinum Resistance and Overcoming It

Ovarian cancer is the most lethal gynecologic malignancy. Platinum-based chemotherapy is the backbone of treatment for ovarian cancer, and although the majority of patients initially have a platinum-sensitive disease, through multiple recurrences, they will acquire resistance. Platinum-resistant recurrent ovarian cancer has a poor prognosis and few treatment options with limited efficacy. Resistance to platinum compounds is a complex process involving multiple mechanisms pertaining not only to the tumoral cell but also to the tumoral microenvironment. In this review, we discuss the molecular mechanism involved in ovarian cancer cells’ resistance to platinum-based chemotherapy, focusing on the alteration of drug influx and efflux pathways, DNA repair, the dysregulation of epigenetic modulation, and the involvement of the tumoral microenvironment in the acquisition of the platinum-resistant phenotype. Furthermore, we review promising alternative treatment approaches that may improve these patients’ poor prognosis, discussing current strategies, novel combinations, and therapeutic agents.

A Novel Four Genes of Prognostic Signature for Uveal Melanoma

Autophagy and immunity play critical roles in various cancers, but the prognostic impact of autophagy and immunity for uveal melanoma (UM) remains lacking. Therefore, the RNA sequencing of data in the TCGA-UVM dataset was downloaded from UCSC Xena database. The prognostic autophagy- and immunity-related genes (AIRGs) were selected via univariate Cox regression. Next, we applied LASSO method to construct four genes of signature in the TCGA-UVM and verified in another two GEO datasets (GSE84976 and GSE22138). This signature intimately associated with overall survival (OS) time and metastasis-free survival (MFS) time of UM, which could be considered as a prognostic indicator. Besides, by applying risk assessment, the patients of UM can be divided into two subgroups (high/low risk) with different survival time, distinct clinical outcomes, and immune microenvironments. Gene set enrichment analysis (GSEA) manifested that cancer hallmark epithelial-mesenchymal transition and KRAS pathways were positively activated in the high-risk group. Moreover, the high-risk group could be more sensitive to chemotherapies than the low-risk group. Thus, our finding suggested that the four genes of signature closely linked with UM risk and survival can afford more accurate survival prediction and potential therapeutic targets for clinical application.

Epi-miRNAs: Regulators of the Histone Modification Machinery in Human Cancer

Cancer is a leading cause of death and disability worldwide. Epigenetic deregulation is one of the most critical mechanisms in carcinogenesis and can be classified into effects on DNA methylation and histone modification. MicroRNAs are small noncoding RNAs involved in fine-tuning their target genes after transcription. Various microRNAs control the expression of histone modifiers and are involved in a variety of cancers. Therefore, overexpression or downregulation of microRNAs can alter cell fate and cause malignancies. In this review, we discuss the role of microRNAs in regulating the histone modification machinery in various cancers, with a focus on the histone-modifying enzymes such as acetylases, deacetylases, methyltransferases, demethylases, kinases, phosphatases, desumoylases, ubiquitinases, and deubiquitinases. Understanding of microRNA-related aberrations underlying histone modifiers in pathogenesis of different cancers can help identify novel therapeutic targets or early detection approaches that allow better management of patients or monitoring of treatment response.

LncRNA LINC01094 contributes to glioma progression by modulating miR-224-5p/CHSY1 axis

Glioma serves as the most common malignancy influencing modern people and is associated with severe morbidity and high mortality. Long non-coding RNAs (lncRNAs) as crucial regulators participate in multiple cancer progression. However, the role of lncRNA LINC01094 in the development of glioma remains unclear. Here, we aimed to explore the effect of lncRNA LINC01094 on the glioma progression and the underlying mechanism. Significantly, we revealed that the expression levels of LINC01094 were elevated in the glioma patient tissues compared to adjacent normal tissues. The LINC01094 expression was enhanced in the glioma cell lines. The depletion of LINC01094 inhibited cell viability and colony formation in the glioma cells. Meanwhile, the migration and invasion of glioma cells were impaired by the depletion of LINC01094. Mechanically, we identified that LINC01094 was able to sponge the miR-224-5p in the glioma cells and miR-224-5p inhibitor could reverse the effect of LINC01094 on glioma progression. In addition, miR-224-5p targeted CHSY1 and LINC01094 up-regulated CHSY1 by targeting miR-224-5p in the glioma cells. LINC01094 promoted glioma progression by the positive regulation of CHSY1. Moreover, tumorigenicity analysis showed that LINC01094 enhanced tumor growth of glioma in vivo. Thus, we conclude that lncRNA LINC01094 promotes glioma progression by modulating miR-224-5p/CHSY1 axis. Our finding provides new insights into the mechanism by which lncRNA LINC01094 contributes to the development of glioma, improving the understanding of lncRNA LINC01094 and glioma. LncRNA LINC01094, miR-224-5p, and CHSY1 may serve as potential targets for glioma.

MicroRNAs as the critical regulators of Cisplatin resistance in ovarian cancer cells

BACKGROUND

Ovarian cancer (OC) is one of the leading causes of cancer related deaths among women. Due to the asymptomatic tumor progression and lack of efficient screening methods, majority of OC patients are diagnosed in advanced tumor stages. A combination of surgical resection and platinum based-therapy is the common treatment option for advanced OC patients. However, tumor relapse is observed in about 70% of cases due to the treatment failure. Cisplatin is widely used as an efficient first-line treatment option for OC; however cisplatin resistance is observed in a noticeable ratio of cases. Regarding, the severe cisplatin side effects, it is required to clarify the molecular biology of cisplatin resistance to improve the clinical outcomes of OC patients. Cisplatin resistance in OC is associated with abnormal drug transportation, increased detoxification, abnormal apoptosis, and abnormal DNA repair ability. MicroRNAs (miRNAs) are critical factors involved in cell proliferation, apoptosis, and chemo resistance. MiRNAs as non-invasive and more stable factors compared with mRNAs, can be introduced as efficient markers of cisplatin response in OC patients.

MAIN BODY

In present review, we have summarized all of the miRNAs that have been associated with cisplatin resistance in OC. We also categorized the miRNAs based on their targets to clarify their probable molecular mechanisms during cisplatin resistance in ovarian tumor cells.

CONCLUSIONS

It was observed that miRNAs mainly exert their role in cisplatin response through regulation of apoptosis, signaling pathways, and transcription factors in OC cells. This review highlighted the miRNAs as important regulators of cisplatin response in ovarian tumor cells. Moreover, present review paves the way of suggesting a non-invasive panel of prediction markers for cisplatin response among OC patients.

The Emerging Role of Non-coding RNAs in Drug Resistance of Ovarian Cancer

Ovarian cancer is one of the most common gynecological malignancies with highest mortality rate among all gynecological malignant tumors. Advanced ovarian cancer patients can obtain a survival benefit from chemotherapy, including platinum drugs and paclitaxel. In more recent years, the administration of poly-ADP ribose polymerase inhibitor to patients with BRCA mutations has significantly improved the progression-free survival of ovarian cancer patients. Nevertheless, primary drug resistance or the acquisition of drug resistance eventually leads to treatment failure and poor outcomes for ovarian cancer patients. The mechanism underlying drug resistance in ovarian cancer is complex and has not been fully elucidated. Interestingly, different non-coding RNAs (ncRNAs), such as circular RNAs, long non-coding RNAs and microRNAs, play a critical role in the development of ovarian cancer. Accumulating evidence has indicated that ncRNAs have important regulatory roles in ovarian cancer resistance to chemotherapy reagents and targeted therapy drugs. In this review, we systematically highlight the emerging roles and the regulatory mechanisms by which ncRNAs affect ovarian cancer chemoresistance. Additionally, we suggest that ncRNAs can be considered as potential diagnostic and prognostic biomarkers as well as novel therapeutic targets for ovarian cancer.

Receptor interacting protein kinase 4 promotes cell proliferation, migration, and invasion in ovarian cancer via targeting protein kinase C delta

Receptor interacting protein kinase 4 (RIPK4) has been reported to function as an oncogenic role in several types of cancers. The aim of this study was to evaluate the role of RIPK4 in ovarian cancer (OC) cells and to elucidate the mechanism behind this effect. In this study, the GEPIA database was used to analyze the RIPK4 expressions in OC tissues and overall survival. qRT-PCR and western blot assay were performed to detect the expressions of RIPK4 and protein kinase C delta (PRKCD) in OC cells. In addition, cell proliferation was assessed by CCK-8 and colony formation assay while cell invasion and migration were evaluated by transwell, wound healing and western blot assay. The interaction of RIPK4 and PRKCD was analyzed by the STRING database and the bioGRID database, and verified with co-immunoprecipitation. Herein, we describe that RIPK4 expression was upregulated in OC tissues and cells and was associated with poor overall survival. RIPK4 silencing repressed the proliferation, migration, and invasion of OC cells. Mechanistically, PRKCD was highly expressed in OC cells and was combined with RIPK4. PRKCD was highly positively associated with RIPK4 in OC and was regulated by RIPK4. Moreover, PRKCD overexpression reversed the inhibitory effects of RIPK4 silencing on OC cell proliferation, migration, and invasion. RIPK4 functions as an oncogene in OC cells via at least partially binding to PRKCD, which might represent a novel therapeutic strategy for improving survival for patients with OC.

MiR-224-5p Targeting OCLN Promotes the Proliferation, Migration, and Invasion of Clear Cell Renal Cell Carcinoma Cells

A number of studies reported that miR-224-5p is involved in a variety of cancer-related cellular processes, yet its physiological role in clear cell renal cell carcinoma (ccRCC) remains unclear. In order to clarify the function of miR-224-5p in ccRCC, real-time quantitative-PCR was conducted to compare the expression of miR-224-5p in human normal renal tubular epithelial cell lines and ccRCC cell lines first, and a strikingly upregulated expression was observed in ccRCC cell lines. Inhibition of miR-224-5p expression by microRNA inhibitors could inhibit the proliferation, migration, and invasion of ccRCC cells. Besides, it was validated by dual-luciferase assay in which miR-224-5p directly targeted OCLN gene. The expression of OCLN was downregulated in ccRCC cells, and overexpression of miR-224-5p could inhibit the mRNA and protein expression levels of OCLN. Overexpression of OCLN could reduce the proliferation, migration, and invasion of ccRCC cells, while overexpressed miR-224-5p could partially reverse that inhibitory effect. Therefore, the promotive effect of miR-224-5p on the proliferation, invasion, and migration of ccRCC cell lines was at least partly due to the inhibition of OCLN expression. These findings highlighted the important function of miR-224-5p, which was promoting cell proliferation, migration, and invasion by downregulating OCLN, in the pathogenesis of ccRCC, and provided a potential treatment strategy.

miRNome and Functional Network Analysis of PGRMC1 Regulated miRNA Target Genes Identify Pathways and Biological Functions Associated With Triple Negative Breast Cancer

Background

Increased expression of the progesterone receptor membrane component 1, a heme and progesterone binding protein, is frequently found in triple negative breast cancer tissue. The basis for the expression of PGRMC1 and its regulation on cellular signaling mechanisms remain largely unknown. Therefore, we aim to study microRNAs that target selective genes and mechanisms that are regulated by PGRMC1 in TNBCs.

Methods

To identify altered miRNAs, whole human miRNome profiling was performed following AG-205 treatment and PGRMC1 silencing. Network analysis identified miRNA target genes while KEGG, REACTOME and Gene ontology were used to explore altered signaling pathways, biological processes, and molecular functions.

Results

KEGG term pathway analysis revealed that upregulated miRNAs target specific genes that are involved in signaling pathways that play a major role in carcinogenesis. While multiple downregulated miRNAs are known oncogenes and have been previously demonstrated to be overexpressed in a variety of cancers. Overlapping miRNA target genes associated with KEGG term pathways were identified and overexpression/amplification of these genes was observed in invasive breast carcinoma tissue from TCGA. Further, the top two genes (CCND1 and YWHAZ) which are highly genetically altered are also associated with poorer overall survival.

Conclusions

Thus, our data demonstrates that therapeutic targeting of PGRMC1 in aggressive breast cancers leads to the activation of miRNAs that target overexpressed genes and deactivation of miRNAs that have oncogenic potential.

MicroRNA-based signatures impacting clinical course and biology of ovarian cancer: a miRNOmics study

Background

In Western countries, ovarian cancer (OC) still represents the leading cause of gynecological cancer-related deaths, despite the remarkable gains in therapeutical options. Novel biomarkers of early diagnosis, prognosis definition and prediction of treatment outcomes are of pivotal importance. Prior studies have shown the potentials of micro-ribonucleic acids (miRNAs) as biomarkers for OC and other cancers.

Methods

We focused on the prognostic and/or predictive potential of miRNAs in OC by conducting a comprehensive array profiling of miRNA expression levels in ovarian tissue samples from 17 non-neoplastic controls, and 60 tumor samples from OC patients treated at the Regina Elena National Cancer Institute (IRE). A set of 54 miRNAs with differential expression in tumor versus normal samples (T/N-deregulated) was identified in the IRE cohort and validated against data from the Cancer Genoma Atlas (TCGA) related to 563 OC patients and 8 non-neoplastic controls. The prognostic/predictive role of the selected 54 biomarkers was tested in reference to survival endpoints and platinum resistance (P-res).

Results

In the IRE cohort, downregulation of the 2 miRNA-signature including miR-99a-5p and miR-320a held a negative prognostic relevance, while upregulation of miR-224-5p was predictive of less favorable event free survival (EFS) and P-res. Data from the TCGA showed that downregulation of 5 miRNAs, i.e., miR-150, miR-30d, miR-342, miR-424, and miR-502, was associated with more favorable EFS and overall survival outcomes, while miR-200a upregulation was predictive of P-res. The 9 miRNAs globally identified were all included into a single biologic signature, which was tested in enrichment analysis using predicted/validated miRNA target genes, followed by network representation of the miRNA-mRNA interactions.

Conclusions

Specific dysregulated microRNA sets in tumor tissue showed predictive/prognostic value in OC, and resulted in a promising biological signature for this disease.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40364-021-00289-6.

Boric acid as a promising agent in the treatment of ovarian cancer: Molecular mechanisms

PURPOSE

The aim of this study is to determine the therapeutic effects of boric acid cell proliferation, invasion, migration, colony formation, cell cycle and apoptosis mechanisms in ovarian cancer cell line under in vitro conditions.

METHODS

MDAH-2774 ovarian cancer cells were employed. Real-time PCR test was used to investigate changes in genes and proteins of cell cycle and apoptosis and identified miRNAs under the addition of boric acid. The apoptosis rates were calculated by TUNEL assay. Matrigel invasion, colony formation and Wound healing tests were used to determine invasion and migration. Oxidative stress index value was calculated for oxidative stress.

RESULTS

Boric acid inhibited cell proliferation, invasion, migration and colony formation, but induces apoptosis and oxidative stress. Also, the expression of miRNA-21, miRNA-200a, miRNA-130a and mi-RNA-224 (which are indicators of poor prognosis of ovarian cancer) decreased significantly.

CONCLUSION

The potential of boric acid as a natural molecule may supports its effectiveness in reducing adverse effects arising from conventional ovarian cancer treatments.

miR-224-5p Carried by Human Umbilical Cord Mesenchymal Stem Cells-Derived Exosomes Regulates Autophagy in Breast Cancer Cells via HOXA5

Objective: In this study, we focused on the potential mechanism of miRNAs carried by human umbilical cord mesenchymal stem cells-derived exosomes (hUCMSCs-exo) in breast cancer (BC).

Methods: RT-qPCR was conducted for the expression of miR-224-5p and HOXA5 in tissues and cells. After co-culture of exosomes and MCF-7 or MDA-MB-231 cells, the cell proliferation was observed by MTT and cell colony formation assay, while apoptosis was measured by flow cytometry. In addition, the expression of HOXA5 and autophagy pathway-related proteins LC3-II, Beclin-1 and P62 was detected by western blotting. And immunofluorescence was applied for detection of LC3 spots. The binding of miR-224-5p to HOXA5 was verified by the luciferase reporter gene assay and RNA-binding protein immunoprecipitation assay. Finally, in vivo experiment was performed to investigate the effect of miR-224-5p on BC growth.

Results: MiR-224-5p was up-regulated and HOXA5 was down-regulated in BC tissues and cells. HOXA5 was confirmed to be the target gene of miR-224-5p. MiR-224-5p carried by hUCMSCs-exo was able to promote the proliferation and autophagy of BC cells, while inhibited apoptosis. Bases on xenograft models in nude mice, it was also revealed that miR-224-5p carried by hUCMSCs-exo could regulate autophagy and contribute to the occurrence and development of BC in vivo.

Conclusion: MiR-224-5p carried by hUCMSCs-exo can regulate autophagy via inhibition of HOXA5, thus affecting the proliferation and apoptosis of BC cells.

MicroRNAs and Long Noncoding RNAs as Novel Therapeutic Targets in Estrogen Receptor-Positive Breast and Ovarian Cancers

Aromatase inhibitors (AIs) such as anastrozole, letrozole, and exemestane have shown to prevent metastasis and angiogenesis in estrogen receptor (ER)-positive breast and ovarian tumors. They function primarily by reducing estrogen production in ER-positive post-menopausal breast and ovarian cancer patients. Unfortunately, current AI-based therapies often have detrimental side-effects, along with acquired resistance, with increased cancer recurrence. Thus, there is an urgent need to identify novel AIs with fewer side effects and improved therapeutic efficacies. In this regard, we and others have recently suggested noncoding RNAs (ncRNAs), specifically microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), as potential molecular targets for utilization in modulating cancer hallmarks and overcoming drug resistance in several cancers, including ER-positive breast and ovarian cancer. Herein, we describe the disruptive functions of several miRNAs and lncRNAs seen in dysregulated cancer metabolism, with a focus on the gene encoding for aromatase (CYP19A1 gene) and estrogen synthesis as a novel therapeutic approach for treating ER-positive breast and ovarian cancers. Furthermore, we discuss the oncogenic and tumor-suppressive roles of several miRNAs (oncogenic miRNAs: MIR125b, MIR155, MIR221/222, MIR128, MIR2052HG, and MIR224; tumor-suppressive miRNAs: Lethal-7f, MIR27B, MIR378, and MIR98) and an oncogenic lncRNA (MIR2052HG) in aromatase-dependent cancers via transcriptional regulation of the CYP19A1 gene. Additionally, we discuss the potential effects of dysregulated miRNAs and lncRNAs on the regulation of critical oncogenic molecules, such as signal transducer, and activator of transcription 3, β-catenin, and integrins. The overall goal of this review is to stimulate further research in this area and to facilitate the development of ncRNA-based approaches for more efficacious treatments of ER-positive breast and ovarian cancer patients, with a slight emphasis on associated treatment–delivery mechanisms.

Downregulated expression levels of USP46 promote the resistance of ovarian cancer to cisplatin and are regulated by PUM2

Ovarian cancer (OC) is a major contributor to cancer‑related mortality in women. Despite numerous drugs being available for the treatment and improving the prognosis of OC, resistance to clinical chemotherapy remains a major obstacle for the treatment of advanced OC. Therefore, determining how to reverse the chemoresistance of OC has become a research hotspot in recent years. The present study aimed to reveal the potential mechanism of OC chemoresistance. Reverse transcription‑quantitative PCR and western blot analysis were performed to detect the expression levels of Ubiquitin‑specific peptidase 46 (USP46) and Pumilio 2 (PUM2) in OC. Cell viability and apoptosis were evaluated by Cell Counting Kit‑8 assay and flow cytometry, respectively. The association between USP46 and PUM2 was assessed by RNA immunoprecipitation. The results of the present study revealed that the expression levels of USP46 which is associated with tumor progression, was downregulated, while PUM2 expression levels were upregulated in cisplatin (DDP)‑resistant OC cells and patient tissues. The downregulation of USP46 expression levels in SKOV3 cells significantly inhibited cell apoptosis and increased cell viability. In SKOV3/DDP cells, the upregulation of USP46 expression levels notably suppressed cell viability and increased cell apoptosis. The results of the RNA immunoprecipitation chip assay demonstrated that PUM2 bound to USP46 and regulated its expression. Furthermore, following the knockdown of USP46 expression, the mRNA and protein expression levels of the cell apoptosis‑related protein, Bcl‑2, were upregulated, whereas the expression levels of caspase‑3, caspase‑9 and Bax were significantly downregulated. In addition, phosphorylated AKT expression levels were notably upregulated. Following the overexpression of USP46 in SKOV3/DDP cells, the opposite trends were observed. In SKOV3 cells, the knockdown of PUM2 could reverse the DDP resistance induced by small interfering RNA‑USP46 as the expression levels of Bcl‑2 were downregulated whereas those of caspase‑3, caspase‑9 and Bax were upregulated compared with the small interfering‑USP46 group. Similarly, in SKOV3/DDP cells, the overexpression of PUM2 could reverse DDP sensitivity induced by the overexpression of USP46. In conclusion, the findings of the present study suggested that the downregulation of USP46 expression levels may promote DDP resistance in OC, which may be regulated by PUM2. Therefore, targeting PUM2/USP46 may be an effective way to reverse DDP resistance in OC.

miR-206 as a prognostic and sensitivity biomarker for platinum chemotherapy in epithelial ovarian cancer

Background

Drug resistance is a major obstacle to successful chemotherapy for epithelial ovarian cancer (EOC). We found a subset of miRNAs associated with the response to first-line platinum-based chemotherapy in EOC by microarray, and miR-206 was one of the most significant miRNAs. The purposes of this study were to evaluate the prognostic and platinum-resistance predictive value of miR-206 in EOC patients and to investigate the functional roles of miR-206 in regulating the platinum resistance of EOC and the underlying mechanism.

Methods

MiRNA expression profiling in EOC specimens was performed using a TaqMan miRNA array. miR-206 expression was confirmed by quantitative real-time PCR (qRT-PCR) analysis. Overexpression of miR-206 in EOC cell lines was achieved by the stable transfection of a recombinant plasmid. In vitro assays of cisplatin cytotoxicity, cell cycle distribution, apoptosis, transwell invasion and cell scratching were employed. Connexin 43 (Cx43) expression was detected by Western blotting. Murine xenograft models were used to determine the effects of miR-206 on platinum resistance in vivo.

Results

miR-206 expression was increased in primary platinum-resistant EOC. High miR-206 expression was related to poor prognosis in EOC patients who received platinum-based chemotherapy and predicted chemoresistance to platinum treatment. Overexpression of miR-206 in cisplatin-sensitive EOC cell lines significantly increased cell viability, migration and invasion in the presence of cisplatin and decreased cisplatin-induced apoptosis. Cx43, a target gene of miR-206, was negatively regulated by miR-206 in EOC cell lines and significantly related to better prognosis in patients who received platinum-based chemotherapy (KmPlot). miR-206 had high expression and Cx43 had low expression in platinum-sensitive EOC cell lines compared with resistant ones. In vivo murine xenograft models showed that miR-206 profoundly promoted the chemoresistance of EOC to cisplatin treatment.

Conclusion

miR-206 was highly expressed in primary platinum-resistant EOCs and functionally promoted platinum resistance in part by downregulating Cx43 expression, thereby providing a useful biomarker for prognostic and platinum-resistance prediction.

LncRNA HCG11 Suppresses Cell Proliferation and Promotes Apoptosis via Sponging miR-224-3p in Non-Small-Cell Lung Cancer Cells

INTRODUCTION

Studies have found that Lnc-HCG11 is an important regulator of cancer. However, the function of Lnc-HCG11 in NSCLC is not known. Therefore, this experimental design was based on Lnc-HCG11 to explore the pathogenesis of NSCLC.

METHODS

RT-qPCR was used to detect the expression of Lnc-HCG11 and miR-224-3p in NSCLC. The effects of Lnc-HCG11 and miR-224-3p on proliferation and apoptosis of NSCLC cells were detected by CCK-8 assay, Edu assay and Annexin V-FITC/PI assay. Target gene prediction and screening, luciferase reporter assays were used to verify downstream target genes for lnc-HCG11 and miR-224-3p. Western blotting was used to detect the protein expression of caspase-3. The tumor changes in mice were detected by in vivo.

RESULTS

Lnc-HCG11 was significantly reduced in NSCLC. Lnc-HCG11 significantly inhibited cell proliferation of NSCLC cells and induced apoptosis. miR-224-3p was significantly elevated in the NSCLC cell line. Moreover, miR-224-3p significantly increased cell proliferation and inhibited apoptosis of NSCLC cells. Furthermore, Lnc-HCG11 was negatively correlated with miR-224-3p expression. Lnc-HCG11 over-expression was up-regulated the expression levels of c-caspase-3 and caspase-3. Finally, the results of in vivo animal models confirmed that Lnc-HCG11 inhibited tumor growth by modulating the miR-224-3p/c-caspase-3 axis.

CONCLUSION

Lnc-HCG11 could inhibit the progression of NSCLC by modulating the miR-224-3p/caspase-3 axis, and Lnc-HCG11 may be a potential therapeutic target for NSCLC.

Hsa_circ_0017639 expression promotes gastric cancer proliferation and metastasis by sponging miR-224-5p and upregulating USP3

Gastric cancer (GC) is a common malignant tumor having poor prognosis globally. Circular RNA (circRNA) is a circular endogenous RNA generated by special selective splicing that occurs in various traits. Studies show that hsa_circ_0017639 is abnormally expressed and involved in tumorigenesis. Nevertheless, the hsa_circ_0017639 role in GC is unknown. This study detected hsa_circ_0017639 expression in a GC cell line using RT-qPCR. Subcellular localization of hsa_circ_0017639 was verified via FISH. We assessed correlations amongst miRNA, hsa_circ_0017639 and relative protein levels using luciferase reporter assays and RNA pulldown assays. The data illustrated that in hsa_circ_assays, expression was enhanced in GC cell. Downregulation of hsa_circ_0017639 decreased GC cell proliferation and migration in in vitro and in vivo experiments. RNA pulldown and RT-qPCR analysis verified that hsa_circ_0017639 sponged miR-224-5p. Bioinformatic and luciferase reporter assays validated that miR-224-5p and USP3 were downstream targets of hsa_circ_0017639. Upregulation of USP3 or downregulation of miR-224-5p restored proliferation and migration by MKN-28 and MGC-803 cells after hsa_circ_0017639 silencing. Upregulation of USP3 restored MKN-28 and MGC-803 cell proliferation and migration after overexpression of miR-224-5p. Our collective findings advised that hsa_circ_0017639 takes part in GC progression through regulating the miR-224-5p/USP3 axis, highlighting its potential as an effective GC therapeutic target.

LINC00619 restricts gastric cancer progression by preventing microRNA-224-5p-mediated inhibition of OPCML

Several long intergenic noncoding RNAs (lincRNAs) have been linked to carcinogenesis; however, little is known about the role of LINC00619 in gastric cancer (GC). LINC00619 was identified among differentially expressed lncRNAs linked to gastric cancer based on microarray analysis and its relationships with miR-224-5p and opioid binding protein/cell adhesion molecule-like gene (OPCML) were investigated. LINC00619, miR-224-5p, and OPCML expression were measured in GC tissues and cells. Ectopic expression and depletion experiments were conducted to assess the effects of LINC00619, miR-224-5p and OPCML on cell proliferation, invasion, migration and apoptosis as well as their effects on the expression of apoptosis- and metastasis-related genes (Bcl-2, Bax, MMP-2 and MMP-9). Tumorigenicity in the nude mice was also examined. Gastric cancer was characterized by downregulation of LINC00619 and OPCML and upregulation of miR-224-5p. Additionally, we found that miR-224-5p could interact with both LINC00619 and OPCML. Upregulation of LINC00619, which binds to miR-224-5p, led to decreased miR-224-5p expression while increasing the expression of OPCML, a target gene of miR-224-5p. Overexpression of LINC00619 or OPCML or downregulation of miR-224-5p suppressed cell proliferation, invasion, migration and tumorigenicity while promoting apoptosis in GC. Our results indicated that LINC00619 functions as a tumor suppressor in GC by impairing miR-224-5p-mediated inhibition of OPCML.

Clinical significance of aberrant microRNAs expression in predicting disease relapse/refractoriness to treatment in diffuse large B-cell lymphoma: A meta-analysis

The clinical significance of aberrantly expressed microRNAs in predicting treatment response to chemotherapy in diffuse large B-cell lymphoma patients (DLBCL) remains uncertain. Feasibility of microRNA testing to predict treatment outcome was evaluated. Twenty-two types of aberrantly expressed microRNAs were associated with poor treatment response; pooled hazard ratio (HR) was 2.14 [95%CI:1.78-2.57, P < 0.00001]. DLBCL patients with aberrant expression of miR-155, miR-17/92 clusters, miR-21, miR-224, or miR-146b-5p had a higher risk of treatment resistance or shorter period of disease relapse/progression free survival, with HR = 2.71 (95%CI:1.66-4.42, P < 0.0001), HR = 2.70 (95%CI:1.50-4.85, P = 0.0010), HR = 2.20 (95%CI:1.31-3.69, P = 0.003), HR = 2.07 (95%CI:1.50-2.86, P < 0.00001), HR = 2.26 (95%CI:1.40-3.65, P = 0.0009), respectively. The association between aberrant expression of microRNAs and treatment response appears to be stronger in formalin-fixed-paraffin-embedded tissue (HR = 2.41, 95%CI:1.79-3.25, P < 0.00001) than in fresh-frozen samples (HR = 1.94, 95%CI: 1.22-3.08, P = 0.005) and peripheral blood samples (HR = 1.94, 95%CI:1.53-2.46, P < 0.00001). Mir-155, miR-17/92 clusters, miR-21, miR-224, and mir-146b-5p have value in predicting treatment response to chemotherapy in DLBCL.

miR-224-5p inhibits proliferation, migration, and invasion by targeting PIK3R3/AKT3 in uveal melanoma

Uveal melanoma (UM) is the most common primary intraocular malignancy in adults. Accumulating investigations have identified the aberrant expression of miRNAs (microRNAs) in UM, such as miR-181, miR-20a, miR-144, miR-146a. The purpose of this study is to investigate the biological function of miR-224-5p in UM. The expression of miR-224-5p, PIK3R3, and AKT3 in 30 tumor tissues and paired adjacent noncancerous tissues were analyzed using Western blot analysis and quantitative real-time polymerase chain reaction (qRT-PCR) assays. Cell proliferation assay, transwell assay, and wound healing assay were used to measure the effects of miR-224-5p on the motility of UM in vitro. Western blot analysis and luciferase assays were used to detect the expression of PIK3R3 and AKT3 as miR-224-5p downstream targets. The results of Western blot analysis and qRT-PCR assays indicated that the expression of miR-224-5p was lower in UM tissues compared to normal tissue, while the expression of PIK3R3 and AKT3 were simultaneously increased. Upregulation of miR-224-5p significantly inhibited capacities of proliferation, invasion, and migration of OCM-1A cells and decreased expression of PIK3R3 and AKT3. Luciferase assay demonstrated PIK3R3 and AKT3 as downstream targets of miR-224-5p. Moreover, upregulating PIK3R3 and AKT3 restrained miR-224-5p-induced inhibition of the motility of OCM-1A cells. Thus, our study proved that miR-224-5p was involved in proliferation, invasion, and migration of UM cells via regulation the expression of PIK3R3 and AKT3. And the results also established a miR-224-5p/PIK3R3/PI3K/AKT axis in the regulation of UM progression, providing an experimental basis for further exploring the miR-224-5p as a therapeutic and diagnosis target for patients with UM.

MicroRNA-224 Promotes Tumorigenesis through Downregulation of Caspase-9 in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) harbors genetic heterogeneity and generally has more aggressive clinical outcomes. As such, there is urgency in identifying new prognostic targets and developing novel therapeutic strategies. In this study, miR-224 was overexpressed in breast cancer cell lines and TNBC primary cancer samples. Knockdown of miR-224 in MDA-MB-231 cancer cells reduced cell proliferation, migration, and invasion. Through integrating in silico prediction algorithms with KEGG pathway and Gene Ontology analyses, CASP9 was identified to be a potential target of miR-224. miR-224 knockdown significantly increased CASP9 transcript and protein levels. Furthermore, luciferase reporter assays confirmed a direct interaction of miR-224 with CASP9. Our findings have demonstrated that the miR-224/CASP9 axis plays an important role in TNBC progression, providing evidence in support of a promising therapeutic strategy for this disease.

Long non‑coding RNA ferritin heavy polypeptide 1 pseudogene 3 controls glioma cell proliferation and apoptosis via regulation of the microRNA‑224‑5p/tumor protein D52 axis

The aim of the present study was to investigate the potential role and regulatory mechanism of long non-coding RNA ferritin heavy polypeptide 1 pseudogene 3 (FTH1P3) in glioma development. The expression of FTH1P3 in low- and high-grade glioma tissues was investigated using reverse transcription-quantitative polymerase chain reaction. FTH1P3 expression was overexpressed or suppressed in U251 glioma cells to examine the involvement of FTH1P3 in glioma cell proliferation and apoptosis using MTT assay and flow cytometry respectively. In addition, the regulatory association between FTH1P3, microRNA (miR)-224-5p and tumor protein (TP) D52 was investigated to elucidate the potential underlying mechanisms of FTH1P3 in glioma by luciferase reporter assay. The results revealed that FTH1P3 was up-regulated in glioma tissues, and FTH1P3 expression in high-grade glioma tissues was significantly higher compared with that in low-grade glioma tissues. Upregulation of FTH1P3 promoted glioma cell proliferation and inhibited apoptosis. Furthermore, FTH1P3 inhibited miR-224-5p expression, which in turn negatively regulated TPD52 expression. Overexpression of miR-224-5p significantly inhibited U251 cell proliferation and induced cellular apoptosis; this effect was clearly reversed following co-transfection of miR-224-5p and TPD52. These data revealed that upregulation of FTH1P3 may have promoted glioma cell proliferation and inhibited apoptosis. Thus, the miR-224-5p/TPD52 axis may be a downstream mechanism of FTH1P3 in glioma progression. The findings of the present study may provide a theoretical basis for the study of the treatment of glioma in the future.

The Network of Non-coding RNAs in Cancer Drug Resistance

Non-coding RNAs (ncRNAs) have been implicated in most cellular functions. The disruption of their function through somatic mutations, genomic imprinting, transcriptional and post-transcriptional regulation, plays an ever-increasing role in cancer development. ncRNAs, including notorious microRNAs, have been thus proposed to function as tumor suppressors or oncogenes, often in a context-dependent fashion. In parallel, ncRNAs with altered expression in cancer have been reported to exert a key role in determining drug sensitivity or restoring drug responsiveness in resistant cells. Acquisition of resistance to anti-cancer drugs is a major hindrance to effective chemotherapy and is one of the most important causes of relapse and mortality in cancer patients. For these reasons, non-coding RNAs have become recent focuses as prognostic agents and modifiers of chemo-sensitivity. This review starts with a brief outline of the role of most studied non-coding RNAs in cancer and then highlights the modulation of cancer drug resistance via known ncRNAs based mechanisms. We identified from literature 388 ncRNA-drugs interactions and analyzed them using an unsupervised approach. Essentially, we performed a network analysis of the non-coding RNAs with direct relations with cancer drugs. Within such a machine-learning framework we detected the most representative ncRNAs-drug associations and groups. We finally discussed the higher integration of the drug-ncRNA clusters with the goal of disentangling effectors from downstream effects and further clarify the involvement of ncRNAs in the cellular mechanisms underlying resistance to cancer treatments.

LncRNA SNHG4 promotes tumour growth by sponging miR-224-3p and predicts poor survival and recurrence in human osteosarcoma

OBJECTIVE

Accumulating data show that dysregulation of long noncoding RNAs (lncRNAs) acts a critical role in a variety of malignancies. Among these lncRNAs, small nucleolar RNA host genes (SNHGs) are associated with tumour growth and progression. But, the molecular mechanisms by which SNHG4 contributes to osteosarcoma remain undocumented.

METHODS

The association between lncRNA SNHG4 expression and clinicopathologic characteristics and prognosis in patients with osteosarcoma was analysed by TCGA RNA-sequencing data. Cell viability and colony formation abilities were respectively assessed by MTT and colony formation assays. LncRNA SNHG4-specific binding with miR-224-3p was verified by bioinformatic analysis, luciferase gene report, and RNA immunoprecipitation assays. Regulation relationship between SNHG4 and miR-224-3p expression was further evaluated by the rescue experiments.

RESULTS

The expression level of lncRNA SNHG4 was significantly elevated in osteosarcoma samples and cell lines as compared with the adjacent normal tissues, and SNHG4 high expression was associated with tumour size (TS) and poor prognosis in patients with osteosarcoma. Knockdown of SNHG4 suppressed cell viability and invasive potential, whereas ectopic SNHG4 expression displayed the opposite effects. Moreover, we found that lncRNA SNHG4 acted as a sponge of miR-224-3p, and miR-224-3p mimic reversed SNHG4 induced tumour-promoting effects in osteosarcoma cells. The expression of miR-224-3p depicted a negative correlation with SNHG4 in osteosarcoma samples and miR-224-3p low expression was associated with TS and poor survival in patients with osteosarcoma.

CONCLUSION

Our findings demonstrated that LncRNA SNHG4 promoted tumour growth by sponging miR-224-3p and represented a poor prognostic factor in patients with osteosarcoma.

Long non-coding RNA Linc00312 modulates the sensitivity of ovarian cancer to cisplatin via the Bcl-2/Caspase-3 signaling pathway

Chemotherapy is one of the main treatments for ovarian cancer (OC). Cisplatin combined with paclitaxel is a commonly used chemotherapy regimen. However, effective cancer therapy is hindered by a patient's resistance to cisplatin. The mechanism that potentially leads to that resistance is unclear. The current study examined the mechanism by which Linc00312 is involved in resistance to cisplatin in OC. Quantitative real-time PCR (RT-qPCR) was used to test for expression of Linc00312 in freshly frozen tissue samples of OC and in SKOV3 and SKOV3/DDP cells. In situ hybridization was performed to examine the distribution of Linc00312 expression in paraffin-embedded histological sections that were sensitive or resistant to cisplatin. The cell counting kit-8 assay was used to detect cell viability. Flow cytometry was used to measure cell apoptosis. RT-qPCR was performed to confirm changes in expression of MDR1, MRP1, Bcl-2, Bax, Caspase-3, and Caspase-9 mRNA. Levels of MDR1, Bcl-2, Bax, Caspase-3, and Caspase-9 protein were detected with Western blotting. Experiments indicated that the expression of Linc00312 decreased significantly in SKOV3/DDP cells compared to that in SKOV3 cells. Upregulation of Linc00312 can considerably increase the sensitivity of SKOV3/DDP cells to cisplatin, while down-regulation of Linc00312 has the exact opposite effect in SKOV3 cells. Linc00312 enhanced the sensitivity of SKOV3/DDP cells to cisplatin by promoting cell apoptosis via the Bcl-2/Caspase-3 signaling pathway. These findings suggest that Linc00312 may be a promising clinical strategy for the treatment of drug-resistant OC.

Reversal of cisplatin resistance by microRNA-139-5p-independent RNF2 downregulation and MAPK inhibition in ovarian cancer

Some microRNAs (miRs) are dysregulated in cancers, and aberrant miR expression has been reported to correlate with chemoresistance of cancer cells. Therefore, the present study aims at investigating the effects of microRNA-139-5p (miR-139-5p) on cisplatin resistance of ovarian cancer (OC) with involvement of ring finger protein 2 (RNF2) and the mitogen-activated protein kinase (MAPK) signaling pathway. OC tissues were obtained from 66 primary OC patients. The cisplatin-sensitive A2780 and cisplatin-resistant A2780/DDP cell lines were collected for construction of RNF2 silencing and overexpressed plasmids. Cell vitality and apoptosis were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and annexin V-FITC/propidium iodide double-staining, respectively. Next, expression of RNF2, extracellular signal-related kinase, and p38 was determined by quantitative reverse transcription-quantitative polymerase chain reaction and Western blot analysis. Finally, the volume of xenograft tumors in BALB/c nude mice was detected. RNF2 and miR-139-5p were identified to be involved in OC. In addition, MAPK activation and RNF2 were related to cisplatin resistance of OC. miR-139-5p was downregulated in cisplatin-resistant OC tissues, and miR-139-5p overexpression could inhibit cell vitality, reduce cisplatin resistance, and promote apoptosis of OC cells. Furthermore, miR-139-5p combined with MAPK inhibitors more obviously reduced cisplatin resistance of OC. Taken together, this study demonstrated that miR-139-5p overexpression combined with inactivation of the MAPK signaling pathway can reverse the cisplatin resistance of OC by suppressing RNF2. Thus, miR-139-5p overexpression might be a future therapeutic strategy for OC.

Circulating microRNA profiles in plasma: identification of miR-224 as a novel diagnostic biomarker in hepatocellular carcinoma independent of hepatic function

Aims

This study was designed to identify novel microRNAs (miRNAs) in plasma for detecting and monitoring hepatocellular carcinoma (HCC), independent of hepatic function and background liver diseases with different etiologies.

Results

(1) Four oncogenic miRNAs (miR-151, 155, 191 and 224) with high expression in HCC tissues were selected as candidates. (2) Quantitative RT-PCR using plasma samples from 107 HCC patients and 75 healthy volunteers revealed a significantly higher level of plasma miR-224 in HCC patients than in healthy volunteers according to a small-scale analysis (P < 0.0001), two independent large-scale cohort analysis (P < 0.0001, AUC 0.908). (3) miR-224 expression was significantly higher in HCC tissues and HCC cell lines than in normal hepatic tissues and fibroblasts, respectively. (P = 0.0011, 0.0150) (4) Plasma miR-224 reflected tumor dynamics; preoperative plasma levels of miR-224 were significantly reduced in postoperative samples (P = 0.0058), and plasma miR-224 levels were significantly correlated with paired miR-224 levels in HCC tissues (P = 0.0005). (5) Furthermore, plasma miR-224 levels significantly discriminated HCC patients from patients with chronic liver disease (P = 0.0008). A high plasma miR-224 level was significantly correlated with larger tumor size (P = 0.0005) and recurrences (P = 0.0027). The plasma miR-224 level could accurately detect small tumors less than 18 mm preoperatively.

Methods

We performed a systematic review of the NCBI database and selected candidate miRNAs reported as highly expressed in HCC tissue.

Conclusions

Plasma miR-224 may be a sensitive biomarker for screening HCC and monitoring tumor dynamics.

Collagen-based three-dimensional culture microenvironment promotes epithelial to mesenchymal transition and drug resistance of human ovarian cancerin vitro

OV-NC and OV-206 cells cultured in collagen I hydrogel scaffolds, could gradually generate multicellular spheroids.

Prognostic Value of microRNA-224 in Various Cancers: A Meta-analysis

BACKGROUND

During previous studies, microRNA-224 (miR-224) was frequently investigated and discovered to be of vital significance to prognosis of patients with various cancers. However, its accurate prognostic value has not been estimated worldwide. Herein, we performed meta-analysis to assess its potential predictive value in a variety of human tumors.

METHODS

Qualified researches were identified up to March 1, 2017 through performing online searches in PubMed, EMBASE, Web of Science and Cochrane Database of Systematic Reviews. Overall survival (OS), disease-free survival (DFS) or progression-free survival (PFS) as a prognosis for various cancers were extracted and calculated, if available. Pooled hazard ratios (HR) and 95% confidence intervals (CI) were calculated using Stata version 13.0 (StataCorp, College Station, Texas, USA).

RESULTS

22 eligible studies with 3000 patients were ultimately brought into the current meta-analysis. It suggested that high miR-224 expression was significantly associated with poor OS in tissue (HR = 1.43, 95% CI = 1.00-2.03). During multivariate analysis, high miR-224 expression was more significantly associated with OS in tissue (HR = 2.81, 95% CI = 1.91-4.13). Likewise, there were significant associations between tissue miR-224 expression and colorectal cancer (CRC), diffuse large B-cell lymphoma (DLBCL) and gastric cancer (GC) patients (p <0.05). Nevertheless, there were not significant associations between high tissue miR-224 expression and DFS (HR = 2.15, 95% CI = 0.97-4.79) or PFS (HR = 0.92, 95% CI = 0.53-1.59).

CONCLUSION

As far as the present researches are concerned, tissue miR-224 has a significantly prognostic value in various cancers, especially in CRC, DLBCL and GC. Due to the complicated pathogenesis of cancers, more large-scale and standard researches are requisite.

MicroRNAs in gynecological cancers: Small molecules with big implications

Gynecological cancers (GCs) are often diagnosed at advanced stages, limiting the efficacy of available therapeutic options. Thus, there remains an urgent and unmet need for innovative research for the efficient clinical management of GC patients. Research over past several years has revealed the enormous promise of miRNAs. These small non-coding RNAs can aid in the diagnosis, prognosis and therapy of all major GCs, viz., ovarian cancers, cervical cancers and endometrial cancers. Mechanistic details of the miRNAs-mediated regulation of multiple biological functions are under constant investigation, and a number of miRNAs are now believed to influence growth, proliferation, invasion, metastasis, chemoresistance and the relapse of different GCs. Modulation of tumor microenvironment by miRNAs can possibly explain some of their reported biological effects. miRNA signatures have been proposed as biomarkers for the early detection of GCs, even the various subtypes of individual GCs. miRNA signatures are also being pursued as predictors of response to therapies. This review catalogs the knowledge gained from collective studies, so as to assess the progress made so far. It is time to ponder over the knowledge gained, so that more meaningful pre-clinical and translational studies can be designed to better realize the potential that miRNAs have to offer.

Influence of microRNAs and Long Non-Coding RNAs in Cancer Chemoresistance

Innate and acquired chemoresistance exhibited by most tumours exposed to conventional chemotherapeutic agents account for the majority of relapse cases in cancer patients. Such chemoresistance phenotypes are of a multi-factorial nature from multiple key molecular players. The discovery of the RNA interference pathway in 1998 and the widespread gene regulatory influences exerted by microRNAs (miRNAs) and other non-coding RNAs have certainly expanded the level of intricacy present for the development of any single physiological phenotype, including cancer chemoresistance. This review article focuses on the latest research efforts in identifying and validating specific key molecular players from the two main families of non-coding RNAs, namely miRNAs and long non-coding RNAs (lncRNAs), having direct or indirect influences in the development of cancer drug resistance properties and how such knowledge can be utilised for novel theranostics in oncology.

Interactions between anticancer active platinum complexes and non-coding RNAs/microRNAs

Platinum(II) complexes such as cisplatin, carboplatin and oxaliplatin are clinically approved for the therapy of various solid tumors. Challenging pathogenic properties of cancer cells and the response of cancers towards platinum-based drugs are strongly influenced by non-coding small RNA molecules, the microRNAs (miRNAs). Both increased platinum activity and formation of tumor resistance towards platinum drugs are controlled by miRNAs. This review gives an overview of the interactions between platinum-based drugs and miRNAs, and their influence on platinum activity in various cancer types is discussed.

Characterization of MicroRNA Expression Profiles in Patients with Giant Cell Tumor

OBJECTIVE

Giant cell tumors of bone (GCTs) are bone destructive neoplasms, the bone resorption being mediated by osteoclasts. Given that microRNAs are crucially involved in tumorigenesis and the modulation of cell fate and behavior, they are promising candidates for regulation of osteoclastogenesis. However, no reliable miRNAs profile for GCT is available. Our study aimed to evaluate osteoclastogenesis-related miRNA expression in GCTs of Chinese patients.

METHODS

From January 2013 to December 2014, 11 patients with GCTs were treated in our department and grouped into a GCT group. A control group comprising four patients with benign tumors of the iliac bone was established. The diagnoses were initially established by imaging examinations and intraoperative frozen sections and later confirmed by standard histologic examination. The GCT group (five male and six female patients) were aged from 17 to 61 years (mean, 32.9 years; SD, 12.8 years). Six patients with GCT underwent intralesional curettage surgery and the other five wide resection. According to Campanacci grading, four patients had Grade I tumors, three Grade II, and three Grade III. The average age of the control group was 28.75 years (SD, 14.24 years); all of them were diagnosed as having benign tumors and underwent iliac grafting. The morphology of the excised tissue was evaluated by examining standardized hematoxylin and eosin (HE) stained paraffin-embedded samples. In all, three osteoclastogenesis-related RNAs and 20 microRNAs (miRNAs) were extracted from the patients. The strength of expression was assessed by quantitative reverse transcription polymerase chain reaction (PCR ) and the results assessed by a Student's t test.

RESULTS

Examination of HE stained sections revealed that the higher the Campanacci grade, the more numerous and bigger the osteoclasts (P < 0.05). PCR results indicated large amounts of osteoclast-related mRNA (cathepsin K, tartrate-resistant acid phosphatase and matrix metalloproteinase9) in GCTs (P < 0.05). Expression of six miRNAs was significantly weaker in the GCT than the control group (P < 0.05). The expression of has-mir-16-5p and has-let-7a-5p was correlated with Campanacci grade in the GCT patients (P = 0.009 and 0.034, respectively). The expression of these two miRNAs may indicate severity of bone destruction.

CONCLUSION

Overall, the clinical utility of six novel miRNA markers for GCTs was demonstrated. Of these, strength of expression of hsa-mir-16-5p and hsa-let-7a-5p may indicate the grade of bone resorption.

TCRP1 expression is associated with platinum sensitivity in human lung and ovarian cancer cells

Platinum-based drugs, including cisplatin (DDP) and oxaliplatin (L-OHP), are among the most potent chemotherapy drugs, and are widely utilized for the treatment of human lung and ovarian cancer. However, certain patients do not respond to platinum-based agents, and even those who initially benefit from the treatment will eventually exhibit resistance to these drugs. Although certain factors have been investigated for their potential to predict platinum resistance, more effective predictors for the improved management of patients with lung and ovarian cancer are required. Tongue cancer resistance-associated protein 1 (TCRP1) is a newly identified gene, which was cloned from a multi-drug resistant cell line of tongue cancer. Previous data has shown that TCRP1 is able to mediate DDP resistance in human oral squamous cell carcinoma cells. However, the contribution of TCRP1 to the resistance of platinum agents in human lung and ovarian cancer cells remains to be elucidated. Our previous study showed that TCRP1 expression levels in samples of lung and ovarian cancer were significantly increased compared with normal controls. In the present study, it was demonstrated that TCRP1 contributed to the resistance to DDP and L-OHP in human lung and ovarian cancer cells. Knockdown of TCRP1 resensitized the cells to the platinum-based agents. The present study identified a positive correlation between TCRP1 expression and primary resistance to DDP and L-OHP in lung cancer cells. In addition, it was observed that cells treated with nuclear factor (NF)-κB inhibitor BAY 11-7082 displayed increased sensitivity to DDP and L-OHP. The results of the present study suggested that TCRP1 may be associated with resistance to DDP and L-OHP in lung and ovarian cancer cells, and the Akt/NF-κB signaling pathway may be involved in the functioning of TCRP1. These findings identify TCRP1 as a potential predictor of platinum resistance in the treatment of lung and ovarian cancer.

Upregulated microRNA-224 promotes ovarian cancer cell proliferation by targeting KLLN

Human epithelial ovarian cancer is a complex disease, with low 5-yr survival rate largely due to the terminal stage at diagnosis in most patients. MicroRNAs play critical roles during epithelial ovarian cancer progression in vivo and have also been shown to regulate characteristic of ovarian cancer cell line in vitro. Alterative microRNA-224 (microRNA-224) expression affects human epithelial ovarian cancer cell survival, apoptosis, and metastasis. However, people know little about the effects of microRNA-224 on epithelial ovarian cancer cell proliferation. In the current study, we found that the microRNA-224 expression level of human syngeneic epithelial ovarian cancer cells HO8910 (low metastatic ability) was lower than that of HO8910PM (high metastatic ability). Furthermore, microRNA-224 was confirmed to target KLLN in HO8910 and HO8910PM. The known KLLN downstream target cyclin A was regulated by microRNA-224 in HO8910 and HO8910PM. In addition, overexpression of microRNA-224 enhanced the proliferation abilities of HO8910 and knockdown of microRNA-224 suppressed the proliferation abilities of HO8910PM by KLLN-cyclin A pathway. Our results provide new data about microRNAs and their targets involved in proliferation of epithelial ovarian cancer cells by modulating the downstream signaling.

Increased fucosylation has a pivotal role in multidrug resistance of breast cancer cells through miR-224-3p targeting FUT4

Fucosylation is the final step in the glycosylation machinery, which produces glycans involved in tumor multidrug resistance development. MicroRNAs (miRNAs) are endogenous negative regulators of gene expression and have been implicated in most cellular processes of tumors, including drug resistance. This study was undertaken to determine the roles of fucosylation and miR-224-3p in multidrug resistance of human breast cancer cell lines. Comparative analysis revealed differential modification patterns of fucosylation of the fucosylated N-glycans in drug-resistant T47D/ADR cells and sensitive line T47D cells. The expressional profiles of fucosyltransferase genes in two pairs of parental and chemoresistant human breast cancer cell lines showed that FUT4 was up-regulated highly in MDR cell lines. Altered level of FUT4 affected the drug-resistant phenotype of T47D and T47D/ADR cells both in vitro and in vivo. By bioinformatics analysis, we identified FUT4 as one of the miR-224-3p-targeted genes. Further studies showed an inverse relationship between of FUT4 and miR-224-3p in parental and ADR-resistant breast cancer cells, wherein miR-224-3p was downregulated in resistant cells. 3'-UTR dual-luciferase reporter assay confirmed that miR-224-3p directly targeted 3'-untranslation region (3'-UTR) of FUT4 mRNA. In addition, miR-224-3p overexpression sensitized T47D/ADR cells to chemotherapeutics and reduced the growth rate of breast cancer xenografts in vivo. Our results indicate that FUT4 and miR-224-3p are crucial regulators of cancer response to chemotherapy, and may serve as therapeutic targets to reverse chemotherapy resistance in breast cancer.

Extremely Low-Frequency Electromagnetic Fields Affect the miRNA-Mediated Regulation of Signaling Pathways in the GC-2 Cell Line

Extremely low-frequency electromagnetic fields (ELF-EMFs) can affect male reproductive function, but the underlying mechanism of this effect remains unknown. miRNA-mediated regulation has been implicated as an important epigenetic mechanism for regulatory pathways. Herein, we profiled miRNA expression in response to ELF-EMFs in vitro. Mouse spermatocyte-derived GC–2 cells were intermittently exposed to a 50 Hz ELF-EMF for 72 h (5 min on/10 min off) at magnetic field intensities of 1 mT, 2 mT and 3 mT. Cell viability was assessed using the CCK–8 assay. Apoptosis and the cell cycle were analyzed with flow cytometry. miRNA expression was profiled using Affymetrix Mouse Genechip miRNA 3.0 arrays. Our data showed that the growth, apoptosis or cell cycle arrest of GC–2 cells exposed to the 50 Hz ELF-EMF did not significantly change. However, we identified a total of 55 miRNAs whose expression significantly changed compared with the sham group, including 19 differentially expressed miRNAs (7 miRNAs were upregulated, and 12 were downregulated) in the 1 mT exposure group and 36 (9 miRNAs were upregulated, and 27 were downregulated) in the 3 mT exposure group. The changes in the expression of 15 selected miRNAs measured by real-time PCR were consistent with the microarray results. A network analysis was used to predict core miRNAs and target genes, including miR-30e-5p, miR-210-5p, miR-196b-5p, miR-504-3p, miR-669c-5p and miR-455-3p. We found that these miRNAs were differentially expressed in response to different magnetic field intensities of ELF-EMFs. GO term and KEGG pathway annotation based on the miRNA expression profiling results showed that miRNAs may regulate circadian rhythms, cytokine-cytokine receptor interactions and the p53 signaling pathway. These results suggested that miRNAs could serve as potential biomarkers, and the miRNA-mediated regulation of signaling pathways might play significant roles in the biological effects of ELF-EMFs.

MicroRNA-224: as a potential target for miR-based therapy of cancer

MicroRNAs (miRNAs) are small noncoding RNA molecules which regulate the target gene expression posttranscriptionally. Increasing studies have shown that microRNAs play important roles in multiple biological pathways. For instance, aberrant expression of microRNA-224 (miR-224) plays a vital role in tumor biology in various types of human cancer. Here, we aim to summarize the molecular mechanisms that lead to the overexpression of miR-224 in cancers, analyze the effect of miR-224 on tumor biology, and reveal the clinical significance of miR-224. MiR-224 regulates its targets by modulating messenger RNA (mRNA) stability and/or protein translation, and it would provide new insight into molecular targeting cancer treatment.

MicroRNA-224 targets ERG2 and contributes to malignant progressions of meningioma

MicroRNA-224 is overexpressed in various malignant tumors with poor prognosis, which plays a critical role in biological processes including cell proliferation, apoptosis and several developmental and physiological progressions. However, the potential association between miR-224 and clinical outcome in patients with meningiomas remains unknown. Here, we investigate miR-224 expression and biological functions in meningiomas. MiR-224 expression was measured by Northern blot analysis and quantitative reverse transcription-polymerase chain reaction (qRT-PCR) in meningioma and normal brain tissues. Kaplan-Meier analysis and Cox regression analysis were used to exam its correlation with clinicopathological features and prognostic value. The biological effects of miR-224 on the cell proliferation and apoptosis in meningioma cells were examined by MTT assay and apoptosis assay. We found the expression levels of miR-224 were significantly higher in meningioma tissues than that in normal brain, positively correlated with advanced pathological grade. Kaplan-Meier analysis indicated that meningioma patients with low miR-224 expression exhibited significantly prolonged overall and recurrence-free survival. Furthermore, we demonstrated that ERG2 was an identical candidate target gene of MiR-224 in vitro. Our results indicated that downregulation of miR-224 suppressed cell growth and resulted in the enhancement of cell apoptosis through activation of the ERG2-BAK-induced apoptosis pathway. Our findings imply the miR-224 expression could predict the overall survival and recurrence-free survival of patients with meningioma and it might be a promising therapeutic target for treating malignant meningiomas.