MicroRNA-564 is downregulated in glioblastoma and inhibited proliferation and invasion of glioblastoma cells by targeting TGF-β1

Analysis of MicroRNA Cargo in Circulating Extracellular Vesicles from HIV-Infected Individuals with Pulmonary Hypertension

The risk of developing pulmonary hypertension (PH) in people living with HIV is at least 300-fold higher than in the general population, and illicit drug use further potentiates the development of HIV-associated PH. The relevance of extracellular vesicles (EVs) containing both coding as well as non-coding RNAs in PH secondary to HIV infection and drug abuse is yet to be explored. We here compared the miRNA cargo of plasma-derived EVs from HIV-infected stimulant users with (HIV + Stimulants + PH) and without PH (HIV + Stimulants) using small RNA sequencing. The data were compared with 12 PH datasets available in the GEO database to identify potential candidate gene targets for differentially altered miRNAs using the following functional analysis tools: ingenuity pathway analysis (IPA), over-representation analysis (ORA), and gene set enrichment analysis (GSEA). MiRNAs involved in promoting cell proliferation and inhibition of intrinsic apoptotic signaling pathways were among the top upregulated miRNAs identified in EVs from the HIV + Stimulants + PH group compared to the HIV + Stimulants group. Alternatively, the downregulated miRNAs in the HIV + Stimulants + PH group suggested an association with the negative regulation of smooth muscle cell proliferation, IL-2 mediated signaling, and transmembrane receptor protein tyrosine kinase signaling pathways. The validation of significantly differentially expressed miRNAs in an independent set of HIV-infected (cocaine users and nondrug users) with and without PH confirmed the upregulation of miR-32-5p, 92-b-3p, and 301a-3p positively regulating cellular proliferation and downregulation of miR-5571, -4670 negatively regulating smooth muscle proliferation in EVs from HIV-PH patients. This increase in miR-301a-3p and decrease in miR-4670 were negatively correlated with the CD4 count and FEV1/FVC ratio, and positively correlated with viral load. Collectively, this data suggest the association of alterations in the miRNA cargo of circulating EVs with HIV-PH.

Role of Non-Coding RNAs in TGF-β Signalling in Glioma

Brain tumours and Gliomas, in particular, are among the primary causes of cancer mortality worldwide. Glioma diagnosis and therapy have not significantly improved despite decades of efforts. Autocrine TGF-β signalling promotes glioma proliferation, invasion, epithelial-to-mesenchymal transition (EMT), and drug resistance. Non-coding RNAs such as miRNA, lncRNA, and circRNAs have emerged as critical transcriptional and post-transcriptional regulators of TGF-β pathway components in glioma. Here, we summarize the complex regulatory network among regulatory ncRNAs and TGF-β pathway during Glioma pathogenesis and discuss their role as potential therapeutic targets for Gliomas.

Systematic characterization and biological functions of non-coding RNAs in glioblastoma

Glioblastoma multiforme (GBM) is the most malignant and aggressive type of glioma. Non-coding RNAs (ncRNAs) are RNAs that do not encode proteins but widely exist in eukaryotic cells. The common characteristics of these RNAs are that they can all be transcribed from the genome without being translated into proteins, thus performing biological functions, particularly microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and circular RNAs. Studies have found that ncRNAs are associated with the occurrence and development of GBM, and there is a complex regulatory network among ncRNAs, which can regulate cell proliferation, migration, apoptosis and differentiation, thus provide a basis for the development of highly specific diagnostic tools and therapeutic strategies in the future. The present review aimed to comprehensively describe the biogenesis, general features and functions of regulatory ncRNAs in GBM, and to interpret the potential biological functions of these ncRNAs in GBM as well as their impact on clinical diagnosis, treatment and prognosis and discusses the potential mechanisms of these RNA subtypes leading to cancer in order to contribute to the better design of personalized GBM therapies in the future.

The Role of microRNAs in Multidrug Resistance of Glioblastoma

Simple Summary

Glioblastoma (GBM) is one of the most malignant types of central nervous system tumor which accounts for more than 60% of all brain tumors in adults. Owing to poor prognosis and drug resistance of most GBM, it is urged to further develop the diagnosis and treatment strategies. The aim of this article is to highlight the roles of some functional microRNAs in the diagnosis and treatment of drug-resistant GBM. Besides, we suggest effective treatment strategies based on the expression profiles of these effective miRNAs to provide an alternative solution to deal with this cancer.

Abstract

Glioblastoma (GBM) is an aggressive brain tumor that develops from neuroglial stem cells and represents a highly heterogeneous group of neoplasms. These tumors are predominantly correlated with a dismal prognosis and poor quality of life. In spite of major advances in developing novel and effective therapeutic strategies for patients with glioblastoma, multidrug resistance (MDR) is considered to be the major reason for treatment failure. Several mechanisms contribute to MDR in GBM, including upregulation of MDR transporters, alterations in the metabolism of drugs, dysregulation of apoptosis, defects in DNA repair, cancer stem cells, and epithelial–mesenchymal transition. MicroRNAs (miRNAs) are a large class of endogenous RNAs that participate in various cell events, including the mechanisms causing MDR in glioblastoma. In this review, we discuss the role of miRNAs in the regulation of the underlying mechanisms in MDR glioblastoma which will open up new avenues of inquiry for the treatment of glioblastoma.

Global miRNA/proteomic analyses identify miRNAs at 14q32 and 3p21, which contribute to features of chronic iron-exposed fallopian tube epithelial cells

Malignant transformation of fallopian tube secretory epithelial cells (FTSECs) is a key contributing event to the development of high-grade serous ovarian carcinoma (HGSOC). Our recent findings implicate oncogenic transformative events in chronic iron-exposed FTSECs, including increased expression of oncogenic mediators, increased telomerase transcripts, and increased growth/migratory potential. Herein, we extend these studies by implementing an integrated transcriptomic and mass spectrometry-based proteomics approach to identify global miRNA and protein alterations, for which we also investigate a subset of these targets to iron-induced functional alterations. Proteomic analysis identified > 4500 proteins, of which 243 targets were differentially expressed. Sixty-five differentially expressed miRNAs were identified, of which 35 were associated with the “top” proteomic molecules (> fourfold change) identified by Ingenuity Pathway Analysis. Twenty of these 35 miRNAs are at the 14q32 locus (encoding a cluster of 54 miRNAs) with potential to be regulated by DNA methylation and histone deacetylation. At 14q32, miR-432-5p and miR-127-3p were ~ 100-fold downregulated whereas miR-138-5p was 16-fold downregulated at 3p21 in chronic iron-exposed FTSECs. Combinatorial treatment with methyltransferase and deacetylation inhibitors reversed expression of these miRNAs, suggesting chronic iron exposure alters miRNA expression via epigenetic alterations. In addition, PAX8, an important target in HGSOC and a potential miRNA target (from IPA) was epigenetically deregulated in iron-exposed FTSECs. However, both PAX8 and ALDH1A2 (another IPA-predicted target) were experimentally identified to be independently regulated by these miRNAs although TERT RNA was partially regulated by miR-138-5p. Interestingly, overexpression of miR-432-5p diminished cell numbers induced by long-term iron exposure in FTSECs. Collectively, our global profiling approaches uncovered patterns of miRNA and proteomic alterations that may be regulated by genome-wide epigenetic alterations and contribute to functional alterations induced by chronic iron exposure in FTSECs. This study may provide a platform to identify future biomarkers for early ovarian cancer detection and new targets for therapy.

MicroRNA-564 inhibits the progression of non-small cell lung cancer via targeting plexin A4

Νon-small cell lung cancer (NSCLC) is the most frequently diagnosed type of cancer, and the most prevalent cause of cancer-associated mortality. The present study aimed to investigate whether microRNA (miR)-564 influences NSCLC progression by regulating NSCLC cell growth and migration, via targeting plexin A4. Therefore, the expression levels of miR-564 and plexin A4 were evaluated in NSCLC specimens or cells using reverse transcription-quantitative PCR. Furthermore, colony formation and Cell Counting Kit-8 assays were performed to determine the proliferative ability of NSCLC cells. The cell migration capacity was assessed using a Transwell assay. In addition, to examine the binding ability of miR-564 on the plexin A4 3'-untranslated region (3'UTR), a dual-luciferase reporter assay was performed. A mouse xenograft model was established to evaluate the effect of miR-564 knockdown on tumor growth in vivo, whereas the expression of plexin A4 and Ki67 in NSCLC tissues was detected using immunohistochemistry. Notably, miR-564 was downregulated in both NSCLC cell lines and tissues, while its overexpression, following transfection with miR-564 mimics, attenuated the proliferation and proliferation, migration and invasion of NSCLC cells. By contrast, silencing of miR-564 using a miR-564 inhibitor promoted NSCLC cell proliferation, migration and invasion. The luciferase assay revealed that miR-564 directly targeted the plexin A4 3'UTR in A549 and H460 cells. Additionally, the overexpression of plexin A4 rescued the effect of miR-564 on NSCLC cell proliferation, migration and invasion abilities. Further in vivo studies demonstrated that miR-564 knockdown promoted NSCLC growth, while miR-564 overexpression resulted in the opposite effect in nude mice. Overall, the results of the present study revealed that miR-564 promotes the proliferation and migration of NSCLC cells, both in vitro and in vivo, via targeting plexin A4. Therefore, miR-564 may be considered as a possible therapeutic target for NSCLC.

Comprehensive genomic profiling of combined small cell lung cancer

Background

Combined small cell lung cancer (CSCLC) is an uncommon and heterogeneous subtype of small cell lung cancer (SCLC). However, there is limited data concerning the different molecular changes and clinical features in CSCLC compared to pure SCLC.

Methods

The clinical and pathological characteristics of pure SCLC and CSCLC patients were analyzed. Immunohistochemistry and microdissection were performed to isolate the CSCLC components. Further molecular analysis was carried out by next-generation sequencing (NGS) in 12 CSCLC and 30 pure SCLC.

Results

There were no significant differences in clinical features between CSCLC and pure SCLC. Overall survival (OS) of CSCLC patients was worse than pure SCLC (P=0.005). NGS results indicated that TP53 and RB1 were the most frequently mutated genes in both CSCLC (83.33% and 66.67%) and pure SCLC (80.00% and 63.33%) groups. However, less than 10% common mutations were found in both CSCLC and pure SCLC. When analyzing the data of SCLC and non-small cell lung cancer (NSCLC) components of CSCLC, more than 50% common mutations, and identical genes with mutations were detected. Moreover, there were also common biological processes and signaling pathways identified in CSCLC and pure SCLC, in addition to SCLC and NSCLC components.

Conclusions

There were no significant differences in terms of clinical features between CSCLC and pure SCLC. However, the prognosis for CSCLC was worse than pure SCLC. NGS analysis suggested that CSCLC components might derive from the same pluripotent single clone with common initial molecular alterations and subsequent acquisitions of other genetic mutations.

MicroRNAs involved in the EGFR pathway in glioblastoma

Glioblastoma (GBM) is the most common primary malignant tumor in adults, and its morbidity and mortality are very high. Although progress has been achieved in the treatment of GBM, such as surgery, chemotherapy and radiotherapy, in recent years, the prognosis of patients with GBM has not improved significantly. MicroRNAs (miRNAs) are endogenous noncoding single-stranded RNAs consisting of approximately 20-22 nucleotides that regulate gene expression at the posttranscriptional level by binding to target protein-encoding mRNAs. Notably, miRNAs regulate various carcinogenic pathways, one of which is the epidermal growth factor receptor (EGFR) signaling pathway, which controls cell proliferation, invasion, migration, angiogenesis and apoptosis. In this review, we summarize the novel discoveries of roles for miRNAs targeting the factors in the EGFR signaling pathway in the occurrence and development of GBM. In addition, we describe their potential roles as biomarkers for the diagnosis and prognosis of GBM and for determining the treatment resistance of GBM and the efficacy of therapeutic drugs.

TMEM63C, a Potential Novel Target for Albuminuria Development, Is Regulated by MicroRNA-564 and Transforming Growth Factor beta in Human Renal Cells

INTRODUCTION

Transmembrane protein (TMEM) 63C is a member of the TMEM gene family and was recently linked to glomerular filtration barrier function and albuminuria. Its molecular function and expression regulation are largely unknown.

OBJECTIVE

In this study, we set out to characterize the regulating impact of microRNAs (miRNAs) such as miRNA-564 (miR-564) on TMEM63C expression in renal cells. Also, we examined the influence of transforming growth factor beta (TGF-ß) on TMEM63C expression and the potential impact of TMEM63C inhibition on epithelial-mesenchymal transition (EMT) in renal cells and on cell viability in human embryonic kidney 293 cells (HEK 293).

METHODS

Expression analyses were done using real-time PCR and Western blot. Dual luciferase assay was performed to determine the miRNA-mediated expression control. Cell viability was assessed via trypan blue exclusion staining.

RESULTS AND CONCLUSIONS

MiR-564 reduced TMEM63C expression in HEK 293 and human podocytes (hPC). The treatment of renal cells with TGF-ß led to an increased expression of TMEM63C. Moreover, a reduced TMEM63C expression was associated with a changed ratio of EMT marker proteins such as α-smooth muscle actin versus E-cadherin in HEK 293 and decreased nephrin expression in hPC. In addition, cell viability was reduced upon inhibition of TMEM63C expression in HEK 293. This study demonstrates first mechanisms involved in TMEM63C expression regulation and a link to EMT in renal cells.

miRNA signature in glioblastoma: Potential biomarkers and therapeutic targets

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

Knockdown of circ_0003340 induces cell apoptosis, inhibits invasion and proliferation through miR-564/TPX2 in esophageal cancer cells

Circular RNA (circRNA) is a promising biomarker of cancer occurrence and development. The different expression levels of circRNAs in various cancers also make them possible therapeutic targets. In this work, we researched the function and underlying mechanisms of circ_0003340 (circ3340) in esophageal cancer EC1 and EC9706 cells. Firstly, we found the expression levels of circ3340 are higher in ESCC and two esophageal cancer cells than in adjacent normal tissues and Het-1a cells. Bioinformatics analysis showed circ3340 has a binding site with miR-564. This was verified by luciferase assay, which revealed that miR-564 can be sponged by circ3340, and that the TPX2 3'UTR is a direct target of miR-564. Upregulation of miR-564 decreased TPX2 protein levels, as shown by Western blot. Moreover, knockdown of circ3340 or enhancement of miR-564 expression had similar effects in EC1 and EC9706 cells, i.e., inducing cell apoptosis, inhibiting cell proliferation, and arresting cell invasion. Downregulation of circ3340 had a negative influence on EC1 and EC9706 cells by affecting the miR-564/TPX2 pathway. Additionally, animal experiments revealed that downregulation of circ3340 inhibited tumor growth in vivo, making circ3340 a potential therapeutic target for patients with esophageal squamous cell cancer.

Inhibitory Effects of Olea europaea Leaf Extract on Mesenchymal Transition Mechanism in Glioblastoma Cells

BACKGROUND

Glioblastoma (GB) is the most aggressive form of brain tumor. Despite the current treatment methods, the survival rate of patients is very low. Therefore, there is a need to develop new therapeutic agents. The migration and invasion capacity of GB cells is related to mesenchymal transition (MT) mechanism.

MATERIALS AND METHODS

The effect of OLE on MT was determined by analysis of the Twist, Snail, Zeb1, N-cadherin and E-cadherin genes in the EMT mechanism. The effect of OLE on cell migration was determined by wound healing test.

RESULTS

2 mg/ml OLE reduced Twist, Snail, Zeb1 and N-cadherin expression and the combination of OLE + TMZ (2 mg/ml OLE + 350 mM TMZ) increased E-cadherin and reduced Twist, Zeb1 and N-cadherin. In addition, co-treatment with OLE increased TMZ-induced anti-invasion properties thought suppressing transcription factors of MT mechanism.

CONCLUSION

OLE can enhance the anti-MT activities of TMZ against GB and provide strong evidence that combined treatment with OLE and TMZ has the potential to be an effective alternative approach in GB therapy.

microRNA-564 inhibits the aggressive phenotypes of papillary thyroid cancer by directly targeting astrocyte-elevated gene-1

Background: Accumulating evidence has revealed that an increasing number of microRNAs (miRNAs) are dysregulated in papillary thyroid cancer (PTC) and that their dysregulation plays an important role in PTC onset and progression. Reportedly, miRNA-564 (miR-564) is downregulated in several types of human cancer. However, its expression profile and specific functions in PTC remain unclear to date. Methods: In this study, we used reverse transcription-quantitative polymerase chain reaction to detect miR-564 expression in PTC tissues and cell lines. Further, the regulatory roles of miR-564 in the malignant development of PTC in vitro and in vivo were examined using a series of functional experiments. In addition, the possible underlying mechanisms and signaling pathways involved were investigated. Results: We demonstrated that miR-564 expression markedly decreased in PTC tissues and cell lines, and this decrease correlated with the lymph node metastasis and tumor-node-metastasis stage. miR-564 upregulation significantly inhibited cell proliferation, migration, and invasion and induced cell apoptosis in vitro as well as hindered tumor growth in vivo. Furthermore, astrocyte-elevated gene-1 (AEG-1) was identified as a direct target gene of miR-564 in PTC cells. Its expression was upregulated and inversely correlated with miR-564 expression in clinically PTC tissues. Additionally, the silencing of AEG-1 expression could imitate the action of miR-564 overexpression in PTC cells. Remarkably, the restoration of AEG-1 expression partially abolished the tumor-suppressing effects induced by a miR-564 upregulation in PTC cells. Ectopic miR-564 expression deactivated the PTEN/Akt pathway in PTC cells in vitro and in vivo. Conclusion: Overall, the findings of the current study suggest that miR-564 is a tumor-suppressive miRNA that exerts crucial roles in the development and progression of PTC. Therefore, this miRNA might be a promising candidate target in the anticancer treatment of patients with PTC.

Aberrant miRNAs Regulate the Biological Hallmarks of Glioblastoma

GBM is the highest incidence in primary intracranial malignancy, and it remains poor prognosis even though the patient is gave standard treatment. Despite decades of intense research, the complex biology of GBM remains elusive. In view of eight hallmarks of cancer which were proposed in 2011, studies related to the eight biological capabilities in GBM have made great progress. From these studies, it can be inferred that miRs, as a mode of post-transcriptional regulation, are involved in regulating these malignant biological hallmarks of GBM. Herein, we discuss state-of-the-art research on how aberrant miRs modulate the eight hallmarks of GBM. The upregulation of 'oncomiRs' or the genetic loss of tumor suppressor miRs is associated with these eight biological capabilities acquired during GBM formation. Furthermore, we also discuss the applicable clinical potential of these research results. MiRs may aid in the diagnosis and prognosis of GBM. Moreover, miRs are also therapeutic targets of GBM. These studies will develop and improve precision medicine for GBM in the future.

Bioinformatics analyses of significant genes, related pathways and candidate prognostic biomarkers in glioblastoma

Glioblastoma (GBM) is the most common type of malignant tumor of the central nervous system. The prognosis of patients with GBM is very poor, with a survival time of ~15 months. GBM is highly heterogeneous and highly aggressive. Surgical removal of intracranial tumors does provide a good advantage for patients as there is a high rate of recurrence. The understanding of this type of cancer needs to be strengthened, and the aim of the present study was to identify gene signatures present in GBM and uncover their potential mechanisms. The gene expression profiles of GSE15824 and GSE51062 were downloaded from the Gene Expression Omnibus database. Normalization of the data from primary GBM samples and normal samples in the two databases was conducted using R software. Then, joint analysis of the data was performed. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed, and the protein‑protein interaction (PPI) network of the differentially expressed genes (DEGs) was constructed using Cytoscape software. Identification of prognostic biomarkers was conducted using UALCAN. In total, 9,341 DEGs were identified in the GBM samples, including 9,175 upregulated genes and 166 downregulated genes. The top 1,000 upregulated DEGs and all of the downregulated DEGs were selected for GO, KEGG and prognostic biomarker analyses. The GO results showed that the upregulated DEGs were significantly enriched in biological processes (BP), including immune response, cell division and cell proliferation, and the downregulated DEGs were also significantly enriched in BP, including cell growth, intracellular signal transduction and signal transduction by protein phosphorylation. KEGG pathway analysis showed that the upregulated DEGs were enriched in circadian entrainment, cytokine‑cytokine receptor interaction and maturity onset diabetes of the young, while the downregulated DEGs were enriched in the TGF‑β signaling pathway, MAPK signaling pathway and pathways in cancer. All of the downregulated genes and the top 1,000 upregulated genes were selected to establish the PPI network, and the sub‑networks revealed that these genes were involved in significant pathways, including olfactory transduction, neuroactive ligand‑receptor interaction and viral carcinogenesis. In total, seven genes were identified as good prognostic biomarkers. In conclusion, the identified DEGs and hub genes contribute to the understanding of the molecular mechanisms underlying the development of GBM and they may be used as diagnostic and prognostic biomarkers and molecular targets for the treatment of patients with GBM in the future.

miR-204 reverses temozolomide resistance and inhibits cancer initiating cells phenotypes by degrading FAP-α in glioblastoma

Malignant gliomas are treated with temozolomide (TMZ) at present, but often exhibit resistance to this agent. Cancer-initiating cells (CICs) have been suggested to lead to TMZ resistance. The mechanisms underlying CICs-based TMZ resistance are not fully understood. MicroRNAs (miRNAs) have been demonstrated to serve important roles in tumorigenesis and TMZ resistance. In the present study, a sphere forming assay and western blot analysis were performed to detect the formation of CICs and fibroblast activation protein α (FAP-α) protein expression. It was revealed that TMZ resistance promoted the formation of CICs and upregulated FAP-α expression in glioblastoma cells. Over-expressing FAP-α was also demonstrated to promote TMZ resistance and induce the formation of CICs in U251MG cells. In addition, using a reverse transcription-quantitative polymerase chain reaction, it was observed that miR-204 was downregulated in U251MG-resistant (-R) cells. miR-204 expression negatively correlated with the FAP-α levels in human glioblastoma tissues, and it may inhibit the formation of CICs and reverse TMZ resistance in U251MG-R cells. Therefore, it was concluded that miR-204 reversed temozolomide resistance and inhibited CICs phenotypes by degrading FAP-α in glioblastoma.

miR-509-3-5P inhibits the invasion and lymphatic metastasis by targeting PODXL and serves as a novel prognostic indicator for gastric cancer

BACKGROUND

Our study aimed to investigate the clinicopathological feature and prognostic role of miR-509-3-5P in gastric cancer, to determine the invasive and metastatic role of miR-509-3-5P in vitro and in vivo and to explore the molecular mechanism between miR-509-3-5P and PODXL.

RESULTS

Strikingly lower miR-509-3-5P expression was detected in gastric cancer tissues with advanced tumor stage, poor differentiation and advanced pT stage, and was regarded as an independent prognostic role for poor prognosis. MiR-509-3-5P expression was markedly down-regulated in gastric cancer cell lines and tissues comparing with normal gastric cell and adjacent normal tissues, respectively. Decreased expression of miR-509-3-5P promoted the colony, migration and invasion abilities of gastric cancer cells in vitro as well as tumorigenesis and lymph node metastasis in vivo. Based on the luciferase assay and tissue microarray, PODXL was regarded as a target gene of miR-509-3-5P.

MATERIALS AND METHODS

The expression of miR-509-3-5P in gastric cancer patients and its clinicopathological relationships as well as prognostic role was studied employing tissue microarray; qRT-PCR was applied to explore miR-509-3-5P expression in gastric cancer cell lines and samples. Moreover, public database was used to analyze the expression of miR-509-3-5P and PODXL. Functional and molecular mechanism experiments were performed in vitro and in vivo.

CONCLUSIONS

Overexpression of miR-509-3-5P inhibits the invasion and metastasis of gastric cancer in vitro and in vivo, functioning as a tumor suppressor, by targeting PODXL. More importantly, miR-509-3-5P was downregulated in gastric cancer tissues and may serve as a novel prognostic indicator for gastric cancer.

miR-564 inhibits hepatocellular carcinoma cell proliferation and invasion by targeting the GRB2-ERK1/2-AKT axis

Recent studies have shown that miR-564 is closely related to the development of various tumors, including breast cancer, lung cancer and glioma. However, few studies have examined miR-564 in hepatocellular carcinoma (HCC). Here, we demonstrated that miR-564 expression in HCC tissues was lower than that in adjacent noncancerous tissues and that miR-564 expression was associated with tumor size, tumor number and vein invasion. Bioinformatics analyses showed that low levels of miR-564 were correlated with poor prognosis. Furthermore, upregulation of miR-564 impaired SMCC7721 and MHCC97H cell proliferation, migration and invasion in vitro and reduced tumorigenesis in vivo. Next, we found that GRB2 was a direct target gene of miR-564 in the HCC cell lines. GRB2 was highly expressed in HCC tissues and negatively correlated with miR-564 expression levels. When GRB2 was downregulated by GRB2-siRNA, HCC cell proliferation, invasion and metastasis were impaired, and restoring GRB2 expression partially reversed the inhibitory effects of miR-564. Western blot analysis showed that miR-564 overexpression reduced GRB2 expression in HCC cell lines and inhibited ERK1/2 and AKT phosphorylation. miR-564 overexpression also upregulated the epithelial-like cell marker E-cadherin and downregulated the interstitial cell-like markers N-cadherin and vimentin. These results suggest that miR-564 inhibits the malignant phenotype of HCC cells by targeting the GRB2-ERK1/2-AKT axis. Consequently, miR-564 may be used as a prognostic marker and therapeutic target for HCC.

Genetic polymorphisms of lncRNA-p53 regulatory network genes are associated with concurrent chemoradiotherapy toxicities and efficacy in nasopharyngeal carcinoma patients

The relevance of the transcription factor p53 in cancer is inarguable, and numerous lncRNAs are involved in the p53 regulatory network as either regulators or effectors, triggering a transcriptional response that causes either cell arrest or apoptosis following DNA damage in a p53-dependent manner. Despite the fact that the therapeutic response is improved in NPC, heterogeneity among people remains with regard to the susceptibility of adverse effects and the efficacy of treatments. Therefore, we analysed eight potentially functional SNPs of five genes in the lncRNA-p53 regulatory network in a discovery cohort of 505 NPC patients. By performing multivariate logistic regression, the impact of genetic variations on the efficacy and risk of CRT-induced toxicities was investigated. The most dramatic finding was that the MEG3 rs10132552 CC genotype had a greater than three-fold increased risk of developing grade 3-4 anaemia (OR = 3.001, 95%CI = 1.355-6.646, P = 0.007). Furthermore, the rs10132552 CT genotype had a better response to treatment (OR = 0.261, 95%CI = 0.089-0.770, P = 0.015). Individuals carrying LINC-ROR rs2027701 with one or two variant alleles had significant associations with a reduced risk of neutropaenia (OR = 0.503, 95%CI = 0.303-0.835, P = 0.008). In conclusion, our results suggested that genetic polymorphisms of the lncRNA-p53 regulatory network could play a potential role in reducing treatment-related toxicities and improving outcomes for NPC patients.