MicroRNAs serving as potential biomarkers and therapeutic targets in nasopharyngeal carcinoma: A critical review

Peripheral hemoglobin to albumin ratio predicts prognosis in patients with nasopharyngeal carcinoma underwent concurrent chemoradiotherapy

BACKGROUND

Recently, the hemoglobin to albumin ratio (HAR) has been shown to be closely associated with the survival of certain malignancies. However, its prognostic value in nasopharyngeal carcinoma (NPC) remained to be elucidated. Herein, we aimed to explore the correlation between HAR and overall survival (OS) in NPC patients treated with concurrent chemoradiotherapy (CCRT).

METHODS

This retrospective study included a total of 858 patients with NPC receiving CCRT between January 2010 and December 2014 in Sun Yat-sen University Cancer Center. We randomly divided them into the training cohort (N = 602) and the validation cohort (N = 206). We performed univariate and multivariate Cox regression analyses to identify variables associated with OS, based on which, a predictive nomogram was constructed and assessed.

RESULTS

In both the training and validation cohorts, patients were classified into low- and high-HAR groups according to the cutoff value determined by the maximally selected rank statistics. This HAR cutoff value effectively divided patients into two distinct prognostic groups with significant differences. Multivariable Cox analysis revealed that higher T-stage, N-stage, and HAR values were significantly related to poorer prognosis in NPC patients and served as independent prognostic factors for NPC. Based on these, a predictive model was constructed and graphically presented as a nomogram, whose predictive performance is satisfactory with a C-index of 0.744 [95%CI: 0.679-0.809] and superior to traditional TNM staging system [C-index = 0.609, 95%CI: 0.448-0.770].

CONCLUSION

The HAR value was an independent predictor for NPC patients treated with CCRT, the predictive model based on HAR with superior predictive performance than traditional TNM staging system might improve individualized survival predictions.

Circular RNA COL1A1 promotes Warburg effect and tumor growth in nasopharyngeal carcinoma

OBJECTIVE

Circular RNAs (circRNAs), pivotal in the pathogenesis and progression of nasopharyngeal carcinoma (NPC), remain a significant point of investigation for potential therapeutic interventions. Our research was driven by the objective to decipher the roles and underlying mechanisms of hsa_circ_0044569 (circCOL1A1) in governing the malignant phenotypes and the Warburg effect in NPC.

METHODS

We systematically collected samples from NPC tissues and normal nasopharyngeal epithelial counterparts. The expression levels of circCOL1A1, microRNA-370-5p (miR-370-5p), and prothymosin alpha (PTMA) were quantitatively determined using quantitative polymerase chain reaction (qPCR) and Western blotting. Transfections in NPC cell lines were conducted using small interfering RNAs (siRNAs) or vectors carrying the pcDNA 3.1 construct for overexpression studies. We interrogated the circCOL1A1/miR-370-5p/PTMA axis's role in cellular functions through a series of assays: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide for cell viability, colony formation for growth, Transwell assays for migration and invasion, and Western blotting for protein expression profiling. To elucidate the molecular interactions, we employed luciferase reporter assays and RNA immunoprecipitation techniques.

RESULTS

Our investigations revealed that circCOL1A1 was a stable circRNA, highly expressed in both NPC tissues and derived cell lines. A correlation analysis with clinical pathological features demonstrated a significant association between circCOL1A1 expression, lymph node metastasis, and the tumor node metastasis staging system of NPC. Functionally, silencing circCOL1A1 led to substantial suppression of cell proliferation, migration, invasion, and metabolic alterations characteristic of the Warburg effect in NPC cells. At the molecular level, circCOL1A1 appeared to modulate PTMA expression by acting as a competitive endogenous RNA or 'sponge' for miR-370-5p, which in turn promoted the malignant characteristics of NPC cells.

CONCLUSION

To conclude, our findings delineate that circCOL1A1 exerts its oncogenic influence in NPC through the modulation of the miR-370-5p/PTMA signaling axis.

Screening of core genes and prediction of ceRNA regulation mechanism of circRNAs in nasopharyngeal carcinoma by bioinformatics analysis

Background: Nasopharyngeal carcinoma (NPC) represents a highly aggressive malignant tumor. Competing endogenous RNAs (ceRNA) regulation is a common regulatory mechanism in tumors. The ceRNA network links the functions between mRNAs and ncRNAs, thus playing an important regulatory role in diseases. This study screened the potential key genes in NPC and predicted regulatory mechanisms using bioinformatics analysis.

Methods: The merged microarray data of three NPC-related mRNA expression microarrays from the Gene Expression Omnibus (GEO) database and the expression data of tumor samples or normal samples from the nasopharynx and tonsil in The Cancer Genome Atlas (TCGA) database were both subjected to differential analysis and Weighted Gene Co-expression Network Analysis (WGCNA). The results from two different databases were intersected with WGCNA results to obtain potential regulatory genes in NPC, followed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment analyses. The hub-gene in candidate genes was discerned through Protein-Protein Interaction (PPI) analysis and its upstream regulatory mechanism was predicted by miRwalk and circbank databases.

Results: Totally 68 upregulated genes and 96 downregulated genes in NPC were screened through GEO and TCGA. According to WGCNA, the NPC-related modules were screened from GEO and TCGA analysis results, and the genes in the modules were obtained. After the results of differential analysis and WGCNA were intersected, 74 differentially expressed candidate genes associated with NPC were discerned. Finally, fibronectin 1 (FN1) was identified as a hub-gene in NPC. Prediction of upstream regulatory mechanisms of FN1 suggested that FN1 may be regulated by ceRNA mechanisms involving multiple circRNAs, thereby influencing NPC progression through ceRNA regulation.

Conclusion: FN1 is identified as a key regulator in NPC development and is likely to be regulated by numerous circRNA-mediated ceRNA mechanisms.

MicroRNA-145-5p modulates Krüppel-like factor 5 and inhibits cell proliferation, migration, and invasion in nasopharyngeal carcinoma

Background

In several human cancers, Krüppel-like factor 5 (KLF5), a zinc finger transcription factor, can contribute to both tumor progression or suppression; however, the precise role of KLF5 in nasopharyngeal carcinoma (NPC) remains poorly understood. In this study, the association between KLF5 and microRNA-145-5p (miR-145-5p) in NPC cells was elucidated.

Results

Our results showed that KLF5 expression was up-regulated in NPC group compared to normal group. We found that KLF5 exhibited an oncogenic role in NPC cells. The upregulation of miR-145-5p inhibited the proliferation, migration, and invasion of NPC cells. It was observed that miR-145-5p could down-regulate the mRNA and protein expression of KLF5 in NPC cell lines. Additionally, the activity of focal adhesion kinase (FAK), a migration marker, was regulated by miR-145-5p and KLF5 in NPC cells.

Conclusions

The results of this study indicated that miR-145-5p could repress the proliferation, migration, and invasion of NPC cells via KLF5/FAK regulation, and could be a potential therapeutic target for patients with NPC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12860-022-00430-9.

Small biomarkers with massive impacts: PI3K/AKT/mTOR signalling and microRNA crosstalk regulate nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is one of the most common malignant tumours of the head and neck in Southeast Asia and southern China. The Phosphatidylinositol 3-kinase/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signalling pathway is involved in processes related to tumour initiation/progression, such as proliferation, apoptosis, metastasis, and drug resistance, and is closely related to the clinicopathological features of NPC. In addition, key genes involved in the PI3K/AKT/mTOR signalling pathway undergo many changes in NPC. More interestingly, a growing body of evidence suggests an interaction between this signalling pathway and microRNAs (miRNAs), a class of small noncoding RNAs. Therefore, in this review, we discuss the interactions between key components of the PI3K/AKT/mTOR signalling pathway and various miRNAs and their importance in NPC pathology and explore potential diagnostic biomarkers and therapeutic targets.

METTL3-mediated m6A modification promotes processing and maturation of pri-miRNA-19a to facilitate nasopharyngeal carcinoma cell proliferation and invasion

The interplay between N6-methyladenosine (m6A) modification and microRNAs (miRs) participates in cancer progression. This study is conducted to explore the role of miR-19a-3p in nasopharyngeal carcinoma (NPC) cell proliferation and invasion. RT-qPCR and western blot showed that miR-19a-3p was upregulated in NPC tissues and cells and related to poor prognosis, methyltransferase-like 3 (METTL3) was highly expressed while BMP and activin membrane-bound inhibitor (BAMBI) was weakly expressed in NPC tissues and cells. miR-19a-3p downregulation inhibited cell proliferation and invasion while miR-19a-3p overexpression played an opposite role. m6A quantification and m6A RNA immunoprecipitation assays showed that METTL3-mediated m6A modification promoted the processing and maturation of pri-miR-19a via DGCR8. Dual-luciferase assay showed that BAMBI was a target of miR-19a-3p. The rescue experiments showed that BAMBI downregulation reversed the role of miR-19a-3p inhibition in NPC cells. A xenograft tumor model showed that METTL3 downregulation inhibited tumor growth via the miR-19a-3p/BAMBI in vivo. Overall, our findings elicited that METTL3-mediated m6A modification facilitated the processing and maturation of pri-miR-19a via DGCR8 to upregulate miR-19a-3p, and miR-19a-3p inhibited BAMBI expression to promote NPC cell proliferation and invasion, thus driving NPC progression.

Splicing factor derived circular RNA circCAMSAP1 accelerates nasopharyngeal carcinoma tumorigenesis via a SERPINH1/c-Myc positive feedback loop

Background

Circular RNAs play an important role in tumor genesis and progression, but they have not been sufficiently studied in patients with nasopharyngeal carcinoma (NPC).

Methods

The circular RNA, circCAMSAP1, was screened in NPC cells by RNA sequencing analysis. The expression of circCAMSAP1 in NPC tissues was examined by real-time quantitative polymerase chain reaction (RT-qPCR) and in situ hybridization. Wound-healing, transwell, MTT and flow cytometry assays, and nude mouse tumor models were used to explore the effect of circCAMSAP1 on proliferation and metastasis of NPC in vitro or in vivo. The downstream proteins regulated by circCAMSAP1 were screened using mass spectrometry. The interaction between circCAMSAP1 and the SERPINH1 mRNA was identified using the circular RNA immunoprecipitation method and the luciferase reporter assay. The interaction between SERPINH1 and transcription factor c-Myc was verified through Co-immunoprecipitation (Co-IP) and immunofluorescence. The effect of c-Myc on the generation of circCAMSAP1 was examined through RT-qPCR and chromatin immunoprecipitation. Finally, the splicing factors that promote the production of circCAMSAP1 were explored by RT-qPCR and RNA immunoprecipitation (RIP).

Results

We found that circCAMSAP1 was highly expressed in NPC tissues and promoted NPC proliferation and metastasis. Additionally, circCAMSAP1 promoted SERPINH1 expression through improved SERPINH1 mRNA stability by binding to the 3′-untranslated region (3’UTR) of SERPINH1. Highly expressed SERPINH1 reduced the ubiquitination-degradation rate of c-Myc, causing increased tumorigenesis. Meanwhile, c-Myc, cooperating with splicing factor 10 (SRSF10), could also promote CAMSAP1 pre-mRNA transcription and back-splicing, forming a positive feedback of circCAMSAP1 production, resulting in the proliferation and metastasis of NPC.

Conclusions

Our findings revealed that circCAMSAP1 promotes NPC proliferation and metastasis by binding to the 3’UTR of SERPINH1, suggesting that the positive feedback of circCAMSAP1-SERPINH1-c-Myc may serve as a prognostic biomarker or therapeutic target in patients with NPC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12943-022-01502-2.

Multimodality Management of EBV-Associated Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is a rare cancer of the nasopharyngeal mucosa with a specific geographic predisposition. NPC is often associated with Epstein-Barr Virus (EBV) infection and as a result contains many characteristic biomarkers. Treatment of locally-contained NPC is generally achieved through use of radiotherapy (RT), as part of a multimodality treatment regimen. Induction chemotherapy followed by concurrent RT and platinum-based chemotherapy regimen has emerged as the definitive treatment of choice for locoregionally-advanced NPC. Recently, immunotherapy is finding a role in the treatment of recurrent or metastatic NPC. Immune checkpoint blockade therapies targeted against the programmed death-1 (PD-1) receptor have demonstrated efficacy in early phase clinical trials, with ongoing phase III trials in effect. Biomarkers for treatment efficacy remain an ongoing area of investigation, with important prognostic implications on the horizon.

Advances in pathogenesis and precision medicine for nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a squamous carcinoma with apparent geographical and racial distribution, mostly prevalent in East and Southeast Asia, particularly concentrated in southern China. The epidemiological trend over the past decades has suggested a substantial reduction in the incidence rate and mortality rate due to NPC. These results may reflect changes in lifestyle and environment, and more importantly, a deeper comprehension of the pathogenic mechanism of NPC, leading to much progress in the preventing, screening, and treating for this cancer. Herein, we present the recent advances on the key signal pathways involved in pathogenesis of NPC, the mechanism of Epstein‐Barr virus (EBV) entry into the cell, and the progress of EBV vaccine and screening biomarkers. We will also discuss in depth the development of various therapeutic approaches including radiotherapy, chemotherapy, surgery, targeted therapy, and immunotherapy. These research advancements have led to a new era of precision medicine in NPC.

Current Status and Future Perspectives about Molecular Biomarkers of Nasopharyngeal Carcinoma

Simple Summary

Nasopharyngeal carcinoma is a serious major public health problem in its endemic countries. Up to 80% of NPC patients with locally advanced disease or distant metastasis at diagnosis were associated with poor prognosis and with median survival less than 4 months. The mortality rate of NPC metastasis is up to 91%. To date, there is no available curative treatment or reliable early diagnosis or prognosis for NPC. Discovery and development of reliable early diagnosis and prognosis biomarkers for nasopharyngeal carcinoma are urgent needed. Hence, we have here listed the potential early diagnosis and prognosis biomarker candidates for nasopharyngeal carcinoma. This review will give an insight to readers on the progress of NPC biomarker discovery to date, as well as future prospective biomarker development and their translation to clinical use.

Abstract

Nasopharyngeal carcinoma (NPC) is an epithelial malignancy that shows a remarkable ethnic and geographical distribution. It is one of the major public health problems in some countries, especially Southern China and Southeast Asia, but rare in most Western countries. Multifactorial interactions such as Epstein–Barr virus infection, individual’s genetic susceptibility, as well as environmental and dietary factors may facilitate the pathogenesis of this malignancy. Late presentation and the complex nature of the disease have led it to become a major cause of mortality. Therefore, an effective, sensitive, and specific molecular biomarker is urgently needed for early disease diagnosis, prognosis, and prediction of metastasis and recurrence after treatment. In this review, we discuss the recent research status of potential biomarker discovery and the problems that need to be explored further for better NPC management. By studying the aberrant pattern of these candidate biomarkers that promote NPC development and progression, we are able to understand the complexity of this malignancy better, hence positing our stands better towards strategies that may provide a way forward to the discovery of more reliable and specific biomarkers for diagnosis and targeted therapeutic development.

Long noncoding RNA SLC9A3‑AS1 increases E2F6 expression by sponging microRNA‑486‑5p and thus facilitates the oncogenesis of nasopharyngeal carcinoma

Long noncoding RNA SLC9A3 antisense RNA 1 (SLC9A3-AS1) plays a central role in lung cancer; yet, its functions in nasopharyngeal carcinoma (NPC) have not been elucidated. The present study revealed the roles of SLC9A3-AS1 in NPC and dissected the mechanisms downstream of SLC9A3-AS1. SLC9A3-AS1 levels in NPC were assessed by applying RT-qPCR. The modulatory role of SLC9A3-AS1 interference on NPC cells was examined using numerous functional experiments. High expression of SLC9A3-AS1 was observed in NPC samples. Patients with NPC with a high level of SLC9A3-AS1 experienced a shorter overall survival than those with a low SLC9A3-AS1 level. Loss of SLC9A3-AS1 reduced NPC cell proliferation, colony formation, migration, and invasion but induced cell apoptosis in vitro. Animal experiments further revealed that the depletion of SLC9A3-AS1 hindered NPC tumour growth in vivo. As a competitive endogenous RNA, SLC9A3-AS1 sponged microRNA-486-5p (miR-486-5p), consequently upregulating E2F transcription factor 6 (E2F6). Finally, the effects of SLC9A3-AS1 silencing on NPC cells were reversed by inhibiting miR-486-5p or overexpressing E2F6. In summary, SLC9A3-AS1 exerted carcinogenic effects on NPC cells by adjusting the miR-486-5p/E2F6 axis. Accordingly, the newly identified SLC9A3-AS1/miR-486-5p/E2F6 pathway may offer attractive therapeutic targets for future development.

Advances in research on microRNAs related to the invasion and metastasis of nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC), which is associated with latent Epstein-Barr virus infection in most cases, is a unique epithelial malignancy arising from the nasopharyngeal mucosal lining. Accumulating evidence provides insights into the genetic and molecular aberrations that likely drive nasopharyngeal tumor development and progression. We review recent analyses of microRNAs (miRNAs), including Epstein-Barr virus-encoded miRNAs (EBV-encoded miRNAs) and dysregulated cellular miRNAs, that may be related to the metastasis of nasopharyngeal carcinoma. The studies summarized herein have greatly expanded our knowledge of the molecular biology of NPC involving miRNAs, and they may provide new biological targets for clinical diagnosis and reveal the potential of microRNA therapeutics. However, much information remains to be uncovered.

Research status and prospects of biomarkers for nasopharyngeal carcinoma in the era of high‑throughput omics (Review)

As a malignant tumor type, nasopharyngeal carcinoma (NPC) is characterized by distinct geographical, ethnic and genetic differences; presenting a major threat to human health in many countries, especially in Southern China. At present, no accurate and effective methods are available for the early diagnosis, efficacious evaluation or prognosis prediction for NPC. As such, a large number of patients have locoregionally advanced NPC at the time of initial diagnosis. Many patients show toxic reactions to overtreatment and have risks of cancer recurrence and distant metastasis owing to insufficient treatment. To solve these clinical problems, high‑throughput '‑omics' technologies are being used to screen and identify specific molecular biomarkers for NPC. Because of the lack of comprehensive descriptions regarding NPC biomarkers, the present study summarized the research progress that has been made in recent years to discover NPC biomarkers, highlighting the existing problems that require exploration. In view of the lack of authoritative reports at present, study design factors that affect the screening of biomarkers are also discussed here and prospects for future research are proposed to provide references for follow‑up studies of NPC biomarkers.

miRNA Expression Characterizes Histological Subtypes and Metastasis in Penile Squamous Cell Carcinoma

Although microRNAs are described as promising biomarkers in many tumor types, little is known about their role in PSCC. Thus, we attempted to identify miRNAs involved in tumor development and metastasis in distinct histological subtypes considering the impact of HPV infection. In a first step, microarray analyses were performed on RNA from formalin-fixed, paraffin-embedded tumor (22), and normal (8) tissue samples. Microarray data were validated for selected miRNAs by qRT-PCR on an enlarged cohort, including 27 tumor and 18 normal tissues. We found 876 significantly differentially expressed miRNAs (p ≤ 0.01) between HPV-positive and HPV-negative tumor samples by microarray analysis. Although no significant differences were detected between normal and tumor tissue in the whole cohort, specific expression patterns occurred in distinct histological subtypes, such as HPV-negative usual PSCC (95 differentially expressed miRNAs, p ≤ 0.05) and HPV-positive basaloid/warty subtypes (247 differentially expressed miRNAs, p ≤ 0.05). Selected miRNAs were confirmed by qRT-PCR. Furthermore, microarray data revealed 118 miRNAs (p ≤ 0.01) that were significantly differentially expressed in metastatic versus non-metastatic usual PSCC. The lower expression levels for miR-137 and miR-328-3p in metastatic usual PSCC were validated by qRT-PCR. The results of this study confirmed that specific miRNAs could serve as potential diagnostic and prognostic markers in single PSCC subtypes and are associated with HPV-dependent pathways.

MicroRNA-384 inhibits nasopharyngeal carcinoma growth and metastasis via binding to Smad5 and suppressing the Wnt/β-catenin axis

Nasopharyngeal carcinoma (NPC) is a major otorhinolaryngological disease with limited effective therapeutic options. This work focused on the function of microRNA-384 (miR-384) on the NPC pathogenesis and the molecules involved. miR-384 expression in cancer tissues and cells was detected. Gain- and loss-of-functions of miR-384 were performed to identify its role in NPC progression. The target mRNA of miR-384 was predicted on an online system and validated through a luciferase reporter assay. The activity of Wnt/β-catenin signaling was detected. Consequently, miR-384 was found to be poorly expressed in NPC tissues and cell lines and was linked to unfavorable survival rates in patients. Overexpression of miR-384 in 6-10B cells suppressed growth, migration, invasion and resistance to apoptosis of cells, but inverse trends were presented in C6661 cells where miR-384 was downregulated. miR-384 targeted Smad5 mRNA. Upregulation of Smad5 counteracted the roles of miR-384 mimic in cells. The NPC-inhibiting effects of miR-384 mimic were also blocked by Wnt/β-catenin activation. To conclude, miR-384 targets Smad5 and inactivates the Wnt/β-catenin pathway, which exerts a suppressing role in NPC cell behaviors as well as tumor growth in vivo. The findings may offer novel thoughts into NPC therapy.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10616-021-00458-3.

Anaplastic Thyroid Carcinoma: Current Issues in Genomics and Therapeutics

PURPOSE OF REVIEW

Anaplastic thyroid carcinoma is a type of thyroid carcinoma with the most aggressive biological behaviour amongst thyroid cancer. Here, we review the current genomic and the impacts of advances in therapies to improve the management of patients with the cancer.

RECENT FINDINGS

Common mutations being identified in anaplastic thyroid carcinoma are p53 and TERT promoter mutations. Other common mutated genes included BRAF, RAS, EIF1AX, PIK3CA, PTEN and AKT1, SWI/SNF, ALK and CDKN2A. Changes in expression of different microRNAs are also involved in the pathogenesis of anaplastic thyroid carcinoma. Curative resection combined with radiotherapy and combination chemotherapies (such as anthracyclines, platins and taxanes) has been shown to have effects in the treatment of some patients with anaplastic thyroid carcinoma. Newer molecular targeted therapies in clinical trials target mostly the cell membrane kinase and downstream proteins. These include targeting the EGFR, FGFR, VEGFR, c-kit, PDGFR and RET on the cell membrane as well as VEGF itself and the downstream targets such as BRAF, MEK and mTOR. Immunotherapy is also being tested in the cancer. Updated knowledge of genomic as well as clinical trials on novel therapies is needed to improve the management of the patients with this aggressive cancer.

Circulating Epstein-Barr virus microRNA profile reveals novel biomarker for nasopharyngeal carcinoma diagnosis

Nasopharyngeal carcinoma (NPC), a tumor quite prevalent in Asia, is closely associated with Epstein-Barr virus (EBV) infection status. Many NPC patients are not able to be treated in time when being diagnosed at an advanced stage. EBV-encoded microRNAs are reliable sources of biomarkers for NPC diagnosis. In this study, we conducted circulating EBV microRNAs profiling by quantitative reverse transcription polymerase chain reaction (qRT-PCR) among plasma samples of 159 NPC patients versus 145 normal controls (NCs) and serum samples of 60 NPC patients versus 60 NCs. Among the 44 mature EBV-encoded miRNAs, only miR-BART19-3p in plasma was proved to be significantly up-regulated in NPC patients (P< 0.05; fold change (FC) > 2.0). The area under the receiver operating characteristic curve (AUC) for the signature to discriminate NPC patients from NCs was 0.848 with the sensitivity and specificity being 71.7% and 72.3%, respectively. The identified biomarker was analyzed in tissue specimens (44 NPC VS. 32 NCs) and proved to be consistently up-regulated in NPC tumor tissues. Bioinformatics analysis was further conducted to predict the potential targets of miR-BART-19-3p, which provided some hints to its close relationship with NPC development. In conclusion, we identified a novel biomarker - plasma miR-BART19-3p for the detection of NPC.

Predictive value and changes of miR-34a after concurrent chemoradiotherapy and its association with cognitive function in patients with nasopharyngeal carcinoma

This study explored the changes and predictive value of miR-34a in nasopharyngeal carcinoma (NPC) after concurrent chemoradiotherapy (CCRT), and its association with cognitive function. Fifty NPC patients admitted to Shunde Hospital, and another fifty healthy individuals were assigned into treated group and control group, respectively. Patients in the treated group received 3 courses of CCRT. The relative expression of miR-34a in the two groups was detected, and the cognitive function of patients was assessed. Diagnostic and predictive values of miR-34a in advanced NPC were analyzed. The expression of miR-34a in the control group was significantly higher than that in the treated group (t=13.364, P<0.001), with an area under the curve (AUC) of 0.979. The expression of miR-34a was significantly upregulated after treatment (t=4.559, P<0.001). After treatment, there were 32 complete remission (CR) patients and 18 partial remission (PR) patients. According to efficacy, CR patients were classified as significant group and PR patients as general group. The expression of miR-34a in the significant group was higher than that in the general group before treatment (t=4.704, P<0.001), with an AUC of 0.852. The Montreal Cognitive Assessment (MoCA) score was significantly decreased after treatment (t=13.042, P<0.001). The expression of miR-34a was positively correlated with the MoCA score after treatment, that is, MoCA score gradually increased with the upregulation of miR-34a expression (r=0.379, P=0.006). There is a positive correlation between miR-34a and cognitive function of patients. Moreover, the expression of miR-34a can be used as a potential predictor of the efficacy of CCRT in patients with NPC.

Clinical utility of Epstein-Barr virus DNA and other liquid biopsy markers in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a malignant epithelial tumor ubiquitously associated with the Epstein-Barr virus (EBV), which is highly prevalent in South China, Southeast Asia, and North Africa. Despite being a highly radio-sensitive and treatable cancer, a majority of NPC patients are diagnosed in their advanced stage, and locoregional and distant relapses following definitive treatment contribute largely to cancer-specific mortality among these patients. Given that EBV-driven NPC is the predominant variant seen in endemic regions, various EBV detection methods have been developed and are utilized in screening, prognostication, and post-treatment surveillance of NPC patients. While the Immunoglobulin A (IgA) serology assay is the most extensively studied EBV detection method, the detection of plasma EBV DNA released during replication or cellular apoptosis has shown superior outcomes in endemic population screening, prognostication, and detection of distant relapse. Furthermore, there is emerging evidence on the use of circulating tumor cells, microRNAs, DNA hypermethylation, and combination assays in various clinical scenarios. Herein, this paper provides a comprehensive overview of the relevant studies using various EBV detection techniques in the management of NPC. Specifically, the recent advances, clinical evidence, and challenges associated with the clinical application of EBV liquid biopsies in population screening, prognostication, and surveillance of NPC are presented.

microRNA-18a from M2 Macrophages Inhibits TGFBR3 to Promote Nasopharyngeal Carcinoma Progression and Tumor Growth via TGF-β Signaling Pathway

OBJECTIVES

Nasopharyngeal carcinoma (NPC) is a type of nasopharyngeal disease with high metastasis and invasion properties. Tumor-associated alternative activated (M2) macrophages are evidenced to connect with NPC. Based on this, this study purposes to explore the mechanism and participation of microRNA-18a (miR-18a) from M2 macrophages in NPC.

METHODS

Peripheral blood mononuclear cells were differentiated to macrophages and macrophages were polarized to M2 type by interleukin-4. SUNE-1 and CNE2 cells were transfected with restored or depleted miR-18a or transforming growth factor-beta III receptor (TGFBR3) to explore their roles in NPC progression with the involvement of the TGF-β signaling pathway. Next, SUNE-1 and CNE2 cells were co-cultured with M2 macrophages that had been treated with restored or depleted miR-18a or TGFBR3 to comprehend their combined roles in NPC with the involvement of the TGF-β signaling pathway.

RESULTS

MiR-18a was highly expressed and TGFBR3 was lowly expressed in NPC cells. MiR-18a restoration, TGFBR3 knockdown or co-culture with miR-18a mimics, or si-TGFBR3-transfected M2 macrophages promoted SUNE-1 cell progression, tumor growth in mice, decreased p-Smad1/t-Smad1, and elevated p-Smad3/t-Smad3. miR-18a downregulation, TGFBR3 overexpression, or co-culture with miR-18a inhibitors or OE-TGFBR3-transfected M2 macrophages depressed CNE2 cell progression, tumor growth in mice, increased p-Smad1/t-Smad1, and decreased p-Smad3/t-Smad3.

CONCLUSION

Our study elucidates that miR-18a from M2 macrophages results in promoted NPC cell progression and tumor growth in nude mice via TGFBR3 repression, along with the Smad1 inactivation and Smad3 activation.

An Integrated Analysis of mRNAs and miRNAs Microarray Profiles to Screen miRNA Signatures Involved in Nasopharyngeal Carcinoma

OBJECTIVE

We aim to identify several microRNAs (miRNAs/miRs)-messenger RNAs (mRNAs) biomarkers correlated to nasopharyngeal carcinoma (NPC) based on an integrated analysis of miRNA and mRNAs microarray expression profiles.

METHODS

The available mRNA and miRNA microarray datasets were retrieved from Gene Expression Omnibus (GEO) database according to pre-determined screening criteria. Differentially expressed miRNA and mRNAs (DEmiRNAs and DEmRNAs) were extracted between NPC and noncancerous nasopharyngeal tissues. The target genes of DEmiRNAs were predicted with miRTarBase followed by the construction of DEmiRNAs-target DEmRNAs network, and functional analyses were performed. The DEmiRNAs expressions were validated and the performance of these DEmiRNAs was assessed by the area under the curve (AUC) values. Finally, the correlations between DEmiRNAs and specific clinical factors were analyzed.

RESULTS

There were 1140 interaction pairs (including let-7d/f-MYC/HMGA2 and miR-452-ITGA9) in DEmiRNAs-target DEmRNAs network. The GO annotation analysis showed that several genes such as MYC, HMGA2 and ITGA9 primarily participated in cellular process. KEGG analysis showed that these targets were associated with cell cycle and cancer-related pathways. Down-regulated let-7(-d and -f) and up-regulated miR-452 were verified in datasets. The AUC values of these 3 DEmiRNAs (let-7d, let-7-f and miR-452) was 0.803, 0.835 and 0.735, respectively. Besides, miR-452 was significantly related to survival rate of NPC patients.

CONCLUSION

The findings implied let-7d/f-MYC/HMGA2 and miR-452-ITGA9 might be promising targets for the detection and treatment of NPC.

Interactions of Vascular Endothelial Growth Factor and p53 with miR-195 in Thyroid Carcinoma: Possible Therapeutic Targets in Aggressive Thyroid Cancers

BACKGROUND

The clinical pathological features, as well as the cellular mechanisms of miR-195, have not been investigated in thyroid carcinoma.

OBJECTIVE

The aim of this study is to identify the interactions of vascular endothelial growth factor (VEGF), p53 and miR-195 in thyroid carcinoma. The clinical and pathological features of miR-195 were also investigated.

METHODS

The expression levels of miR-195 were identified in 123 primary thyroid carcinomas, 40 lymph nodes with metastatic papillary thyroid carcinomas and seven non-neoplastic thyroid tissues (controls) as well as two thyroid carcinoma cell lines, B-CPAP (from metastasizing human papillary thyroid carcinoma) and MB-1 (from anaplastic thyroid carcinoma), by the real-time polymerase chain reaction. Using Western blot and immunofluorescence, the effects of exogenous miR-195 on VEGF-A and p53 protein expression levels were examined. Then, cell cycle and apoptosis assays were performed to evaluate the roles of miR-195 in cell cycle progression and apoptosis.

RESULTS

The expression of miR-195 was downregulated in majority of the papillary thyroid carcinoma tissue as well as in cells. Introduction of exogenous miR-195 resulted in downregulation of VEGF-A and upregulation of p53 protein expressions. Upregulation of miR-195 in thyroid carcinoma cells resulted in cell cycle arrest. Moreover, we demonstrated that miR-195 inhibits cell cycle progression by induction of apoptosis in the thyroid carcinoma cells.

CONCLUSION

Our findings showed for the first time that miR-195 acts as a tumour suppressor and regulates cell cycle progression and apoptosis by targeting VEGF-A and p53 in thyroid carcinoma. The current study exhibited that miR-195 might represent a potential therapeutic target for patients with thyroid carcinomas having aggressive clinical behaviour.

Biomarkers for PTLD diagnosis and therapies

Post-transplant lymphoproliferative disorder (PTLD) represents a spectrum of lymphoproliferative disorders and is a serious complication of pediatric transplantation. The majority of PTLD are associated with Epstein Barr virus (EBV) and the characteristic EBV+ B cell lymphomas are the leading post-transplant malignancy in children. EBV+ PTLD remains a formidable issue in pediatric transplantation and is thought to result from impaired immunity to EBV as a result of immunosuppression. However, the key viral and immune factors that determine whether EBV+ PTLD develops remain unknown. Recently, there has been much interest in developing biomarkers in order to improve and achieve more personalized approaches, in the clinical diagnosis, management, and treatment of EBV+ PTLD. Here, we review the status of immune-, viral-, and B cell lymphoma-derived candidates for biomarkers of EBV+ PTLD.

MiR-34a Inhibits Cell Proliferation and Induces Apoptosis in Human Nasopharyngeal Carcinoma by Targeting lncRNA MCM3AP-AS1

Introduction

MCM3AP-AS1 has been characterized as an oncogenic lncRNA in several types of cancer, while its role in nasopharyngeal carcinoma (NPC) is unknown. This study aimed to investigate the role of MCM3AP-AS1 in NPC.

Patients and Methods

Paired NPC tissues and non-tumor tissues were collected from 55 NPC patients. Expression of MCM3AP-AS1 and miR-34a in paired tissues was analyzed by RT-qPCR. Interactions between MCM3AP-AS1 and miR-34a were analyzed by overexpression experiments. The roles of MCM3AP-AS1 and miR-34a in regulating NPC cell proliferation and apoptosis were explored by cell proliferation assay and cell apoptosis assay, respectively.

Results

Our bioinformatics analysis showed that MCM3AP-AS1 may be targeted by miR-34a, which is a well-studied tumor suppressor miRNA. In this study, we showed that miR-34a was downregulated and MCM3AP-AS1 was upregulated in NPC. An inverse correlation between the expression of MCM3AP-AS1 and miR-34a was found across NPC tissue samples. High expression level of MCM3AP-AS1 and low levels of miR-34a in NPC tissues predicted the poor survival. In NPC cells, overexpression of MCM3AP-AS1 did not affect the expression of miR34a, while overexpression of miR-34a led to downregulated MCM3AP-AS1. Cell proliferation and apoptosis assay showed that overexpression of miR-34a reduced the enhancing effects of overexpressing MCM3AP-AS1 on cell proliferation and the inhibitory effects on cell apoptosis.

Conclusion

MiR-34a inhibits cell proliferation and induces apoptosis in human NPC by targeting MCM3AP-AS1.

MicroRNA-379-5p/YBX1 Axis Regulates Cellular EMT to Suppress Migration and Invasion of Nasopharyngeal Carcinoma Cells

Background

Epithelial–mesenchymal transition (EMT) is a major actor modulating the metastasis of nasopharyngeal carcinoma (NPC). Increasing evidence indicates that microRNAs (miRs) are the important regulators of EMT program. However, the potential roles and underlying mechanisms of miR‑379-5p in regulating EMT of NPC cells remain unclear.

Methods

miR-379-5p expression levels in human NPC tissues and cell lines were detected via quantitative real-time PCR (qRT-PCR). Then, the correlations between miR-379-5p expression in NPC tissues and clinicopathologic features and patients’ prognosis were analyzed. The effect of miR-379-5p on the expression of EMT markers in NPC cells was evaluated by Western blot and qRT-PCR. NPC cells’ migration and invasion were evaluated in vitro by Transwell migration and invasion assays, respectively. The target of miR-379-5p was predicted with three publicly available databases and further validated with dual-luciferase reporter assay, qRT-PCR, and Western blot.

Results

The expression of miR-379-5p was significantly decreased in NPC tissues, and its low expression was significantly associated with multiple unfavorable clinicopathological factors and poor prognosis of NPC patients. Meanwhile, miR-379-5p was downregulated in NPC cell lines, and its exotic expression inhibited EMT to reduce the migration and invasion of NPC cells. Furthermore, Y-box binding protein 1 (YBX1) was identified and validated as a direct target of miR-379-5p, and restoring YBX1 expression could reverse the inhibitive effect of miR-379-5p on NPC cell EMT, migration and invasion.

Conclusion

Taken together, our findings indicate that miR-379-5p inhibits the EMT of NPC cells to reduce their migration and invasion abilities by post-transcriptionally suppressing YBX1 expression, providing a novel potential treatment target for NPC patients.

LncRNA SNHG7 promotes the proliferation of nasopharyngeal carcinoma by miR-514a-5p/ELAVL1 axis

Background

Nasopharyngeal carcinoma (NPC), with distinct geographical distribution, has gathered public attention. Despite that radiotherapy and chemotherapy are applied to treat NPC, cell metastasis still cannot be avoided. Numerous works have elucidated that lncRNAs are essential players in the development of multiple cancers. LncRNA SNHG7 has been reported as a contributing factor in the occurrence of certain cancers, but its mechanism in NPC deserves further investigation. The purpose of the study is to figure out the role and molecular regulation mechanism of SNHG7 in NPC.

Methods

The role of SNHG7 in NPC was verified by CCK-8, colony formation, EdU staining, western blot and capase-3 assays. The interactions between SNHG7/ELAVL1 and miR-514a-5p were confirmed by RNA pull down, RT-qPCR, RIP and luciferase reporter assays.

Results

SNHG7 was upregulated in NPC cells, and absence of SNHG7 suppressed cell proliferation as well as promoted cell apoptosis in NPC. Furthermore, SNHG7 was confirmed to bind with miR-514a-5p and negatively modulate miR-514a-5p expression. Besides, miR-514a-5p was found to be able to bind with ELAVL1 and negatively regulate ELAVL1 mRNA and protein expressions. In the end, rescue assays demonstrated that the miR-514a-5p deficiency restored the NPC progression inhibited by SNHG7 silence, and ELAVL1 partly counteracted the restoration caused by miR-514a-5p inhibitor in HNE1 cells.

Conclusions

LncRNA SNHG7 promotes the proliferation and migration of nasopharyngeal carcinoma by miR-514a-5p/ ELAVL1 axis.

Multiple Mechanisms Involving in Radioresistance of Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is the malignant tumor with ethnic and geographical distribution preference. Although intensity-modulated radiotherapy (IMRT)-based radiotherapy combined with chemotherapy and targeted therapy has dramatically improved the overall survival of NPC patients, there are still some patients suffering from recurrent tumors and the prognosis is poor. Multiple mechanisms may be responsible for radioresistance of NPC, such as cancer stem cells (CSCs) existence, gene mutation or aberrant expression of genes, epigenetic modification of genes, abnormal activation of certain signaling pathways, alteration of tumor microenvironment, stress granules (SGs) formation, etc. We conduct a comprehensive review of the published literatures focusing on the causes of radioresistance, retrospect the regulation mechanisms following radiation, and discuss future directions of overcoming the resistance to radiation.

MiRNAs in Radiotherapy Resistance of Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is one of the most common malignant tumors of the head and neck in Southeast Asia and southern China. Although the comprehensive treatment based on intensity-modulated radiation therapy improves outcomes, the five-year survival rate of NPC patients is low, and the recurrence remains high. Radiotherapy resistance is the main cause of poor prognosis in NPC patients. MicroRNAs (miRNAs) are a class of endogenous non-coding RNAs regulating various biological functions in eukaryotes. These miRNAs can regulate the development and progression of nasopharyngeal carcinoma by affecting the proliferation, apoptosis, movement, invasion and metastasis of NPC cells. The abnormal expression of miRNAs is closely related to radiotherapy sensitivity and prognosis of NPC patients, which can affect the transmission of related signaling pathways by regulating the expression of tumor suppressor genes and / or oncogenes, and therefore participate in radiotherapy resistance in nasopharyngeal carcinoma. Here, we review the mechanisms by which miRNAs may be involved in the radiotherapy resistance of nasopharyngeal carcinoma.

[Chloroquine enhances cisplatin-induced apoptosis of nasopharyngeal carcinoma cells by inhibiting autophagy via upregulating miR129]

OBJECTIVE

To investigate the role of miR129 in mediating the effect of chloroquine to enhance cisplatin- induced apoptosis in nasopharyngeal carcinoma cells (HNE1).

METHODS

MTT assay was used to detect the viability of HNE1 cells treated with different concentrations of cisplatin. Colony formation of HNE1 cells treated with cisplatin and chloroquine, alone or in combination, was observed using crystal violet staining. BALB/C unde mice were inoculated with HNE1 cells and randomly divided into 4 groups with 6 mice in each group. The mice received intraperitoneal injections of cisplatin and chloroquine, alone or in combination once every 3 days for 4 consecutive weeks, and the tumor growth was observed in each group. The expression of miR129 in HNE1 cells treated with chloroquine, cisplatin, or both was detected with qPCR. The effects of miR129 suppression with a miR129 inhibitor on the expressions of autophagy related proteins p62, LC3B, Beclin1 and the drug-resistant related protein P-glycoprotein (P-gp) were examined using Western blotting in HNE1 cells treated with chloroquine, cisplatin, or both; the changes in cell apoptosis were detected Annexin V/PI double staining.

RESULTS

Chloroquine combined with cisplatin significantly inhibited HNE1 cell proliferation in vitro and the growth of HNE1 cell-derived tumor in nude mice as compared with cisplatin alone (P < 0.01). In cultured HNE1 cells, inhibition of the expression of miR129 significantly promoted autophagy and up-regulated P-gp expression (P < 0.01); Chloroquine obviously inhibited cisplatin-induced autophagy and up-regulated the expression of miR129 in HNE1 cells (P < 0.01). Transfection of the cells with the miR129 inhibitor abolished the inhibitory effect of chloroquine on cisplatin-induced autophagy, and significantly increased the cell survival rate (P < 0.05) and lower the cell apoptotic rate (P < 0.01) after combined treatment with chloroquine and cisplatin.

CONCLUSIONS

Chloroquine enhances the pro-apoptotic effect of cisplatin by up-regulating miR129 to inhibit autophagy and drug resistance in HNE1 cells.

Identification of a 7-microRNA signature in plasma as promising biomarker for nasopharyngeal carcinoma detection

Background

Circulating microRNAs (miRNAs) have become reliable sources of non‐invasive biomarkers for cancer diagnosis. Identification of promising miRNA biomarkers in plasma might benefit a lot to the detection of nasopharyngeal carcinoma (NPC).

Methods

The Exiqon miRNA qPCR panel was used in the screening stage to identify candidate miRNAs, which were further verified by quantitative reverse transcription polymerase chain reaction (qRT‐PCR) in the following three stages among plasma samples from 200 NPC patients and 189 healthy donors (as normal controls [NCs]). The identified miRNAs were further explored in tissue specimens (48 NPC vs 32 NCs) and plasma exosomes (32 NPC vs 32 NCs). Survival analyses were ultimately conducted by Cox regression models and Kaplan‐Meier curves using log‐rank tests.

Results

We identified a 7‐miRNA signature including let‐7b‐5p, miR‐140‐3p, miR‐144‐3p, miR‐17‐5p, miR‐20a‐5p, miR‐20b‐5p, and miR‐205‐5p in plasma for NPC diagnosis after four‐stage validation. The areas under the receiver operating characteristic curve (AUCs) for the signature were 0.879, 0.884, 0.921, and 0.807 for the training, testing, external validation stage, and the combined three stages, respectively. In NPC tissues, miR‐144‐3p, miR‐17‐5p, miR‐20a‐5p, and miR‐205‐5p were consistently up‐regulated while let‐7b‐5p and miR‐140‐3p were significantly down‐regulated compared to NCs. However, none of the seven identified miRNAs were dysregulated in plasma‐derived exosomes in NPC patients. As to survival analysis, none of the seven miRNAs seemed to be associated with NPC prognosis.

Conclusion

We identified a 7‐miRNA signature in plasma as promising non‐invasive biomarkers for NPC detection.

LncRNA XIST knockdown suppresses the malignancy of human nasopharyngeal carcinoma through XIST/miRNA-148a-3p/ADAM17 pathway in vitro and in vivo

BACKGROUND

Long non-coding RNA (lncRNA) X inactivate-specific transcript (XIST) has been verified as an oncogenic gene in human cancers, including nasopharyngeal carcinoma (NPC). However, the role of XIST in NPC remains to be largely uncovered, as well as its underlying mechanism.

METHODS

Expression of XIST, miR-148a-3p and ADAM17 was detected using qPCR and western blot assay. Cell proliferation and apoptosis assay were measured with MTT and flow cytometry, separately. Migration and invasion abilities were examined by transwell assays. Epithelial-mesenchymal transition (EMT) was assessed by western blot analyzing levels of E-cadherin, N-cadherin and vimentin. The potential binding between miR-148a-3p and XIST/ADAM17 was validated by luciferase reporter assay, Ago2-RNA immunoprecipitation and RNA pull-down assay. Xenograft experiments were conducted to measure tumor growth.

RESULTS

XIST was upregulated and miR-148a-3p was downregulated in NPC tissues and cell lines. Both XIST knockdown and miR-148a-3p overexpression promoted apoptosis, suppressed cell proliferation, migration, invasion, and EMT of NPC cells in vitro. In addition, miR-148a-3p was validated as a target of XIST, and silencing of miR-148a-3p could reverse XIST knockdown-mediated functions in SUNE-1 and CNE2 cells. Furthermore, miR-148a-3p was identified to target ADAM17, and ectopic expression of ADAM17 could abate miR-148a-3p-induced effects as well. Notably, ADAM17 was downregulated by XIST knockdown through upregulating miR-148a-3p. In vivo, XIST knockdown resulted in a slower tumor growth.

CONCLUSION

Knockdown of XIST suppresses the malignant progression of NPC cells through targeting miR-148a-3p/ADAM17 axis both in vitro and in vivo.

MicroRNA expression profiling analysis in serum for nasopharyngeal carcinoma diagnosis

BACKGROUND

Circulating microRNAs have become reliable sources of non-invasive biomarkers for cancer diagnosis. miRNA expression analysis in blood circulation for the identification of novel signatures might assist the early detection of nasopharyngeal carcinoma (NPC) patients.

METHODS

In the screening stage, the Exiqon miRNA qPCR panel was applied for the selection of candidate miRNAs. Serum samples taken from 208 NPC patients and 238 healthy donors (as normal controls (NCs)) were assigned to into the following three stages (training (30 NPC VS. 30 NCs), testing (138 NPC VS. 166 NCs) and external validation stage (40 NPC VS. 42 NCs)) for further confirmation of differently expressed miRNAs using qRT-PCR. The identified miRNA signatures were further explored in tissue specimens (48 NPC VS. 32 NCs) and serum-derived exosomes samples (32 NPC VS. 32 NCs).

RESULTS

Five miRNAs in serum including let-7b-5p, miR-140-3p, miR-192-5p, miR-223-3p and miR-24-3p were found to be significantly up-regulated in NPC patients compared to NCs. The five identified miRNAs were further combined into one panel and the areas under the receiver operating characteristic curve (AUCs) for three independent stages were 0.910 (training), 0.916 (testing) and 0.968 (external validation), respectively. miR-192-5p and miR-24-3p were consistently up-regulated in NPC tissues while let-7b-5p and miR-140-3p were conversely down-regulated. In serum-derived exosomes samples, no expression difference was observed between NPC patients and NCs.

CONCLUSION

A five-miRNA signature was identified in serum to be potential biomarkers for NPC detection.

Association Between LMP-1, LMP-2, and miR-155 Expression as Potential Biomarker in Nasopharyngeal Carcinoma Patients: A Case/Control Study in Vietnam

Background: Epstein-Barr virus (EBV) infection and microRNA-155 (miR-155) are considered etiological factors that contribute to nasopharyngeal carcinoma (NPC). The regulation of miR-155 expression induced by EBV infection has been reported to be important in NPC tumorigenesis. Aims: This study was designed to explore the relationships among the expression levels of miR-155, LMP-1 (latent membrane protein-1), and LMP-2 (latent membrane protein-2) in tumor and nontumor specimens of Vietnamese NPC patients. The study was also designed to investigate the association between miR-155 expression and LMP-1 and LMP-2 expression in Vietnamese NPC patients. Materials and Methods: Ninety-three NPC biopsy samples and 100 noncancerous swab specimens were collected from patients and analyzed by real-time reverse transcriptase polymerase chain reaction. Results: LMP-1, LMP2, and miR-155 were significantly upregulated in 76.34%, 67.74%, and 75.27% of NPC samples, respectively, with decreased expression observed in the control group (p < 0.0001). Moreover, the statistical analysis showed that there was a close association between LMP-1 and LMP-2 expression and miR-155 expression in the NPC samples. Conclusion: miR-155 expression was upregulated and significantly associated with the expression of LMP-1 and LMP-2, in Vietnamese NPC cases.

LINC00958 Promotes The Malignancy Of Nasopharyngeal Carcinoma By Sponging microRNA-625 And Thus Upregulating NUAK1

Purpose

The aberrant expression of long noncoding RNAs (lncRNAs) indicates progression of various diseases. LINC00958 has been well studied in several types of human cancer; however, the expression profile, functions, and potential mechanism of action of this lncRNA in nasopharyngeal carcinoma (NPC) remain largely unclear and still need to be elucidated. In the present study, we aimed to measure LINC00958 expression in NPC, determine its clinical value, and explore its roles in NPC progression as well as the mechanisms behind these processes.

Methods

The expression profile of LINC00958 in NPC was evaluated by reverse-transcription quantitative polymerase chain reaction (RT-qPCR). A series of functional assays, including the Cell Counting Kit-8 assay, flow cytometry, a Transwell assay, and an in vivo nude mouse model, were utilized to determine the participation of LINC00958 in the malignancy of NPC.

Results

LINC00958 was found to be upregulated in NPC tissue specimens and cell lines. The LINC00958 overexpression significantly correlated with tumor size, lymph node status, TNM stage, and worse overall survival among NPC patients. Downregulation of LINC00958 suppressed NPC cell proliferation, migration, and invasion and induced apoptosis in vitro. Additionally, the LINC00958 knockdown impaired tumor growth in vivo. Mechanistically, LINC00958 was found to serve as a molecular sponge of microRNA-625 (miR-625), thereby upregulating NUAK family SNF1-like kinase 1 (NUAK1) in NPC cells. Lastly, rescue experiments validated the involvement of the miR-625–NUAK1 axis in LINC00958-mediated biological functions in NPC.

Conclusion

Our results demonstrated that LINC00958 works as an oncogene in NPC and plays a key role in the malignant phenotype of NPC cells by sponging miR-625 and increasing NUAK1 expression. The LINC00958–miR-625–NUAK1 pathway might be a target for anticancer therapy in patients with NPC.

The four‑microRNA signature identified by bioinformatics analysis predicts the prognosis of nasopharyngeal carcinoma patients

The aim of the present study was to identify microRNAs (miRNAs) that predict the prognosis of patients with nasopharyngeal carcinoma by integrated bioinformatics analysis. First, the original microarray dataset GSE32960, including 312 nasopharyngeal carcinomas and 18 normal samples, was downloaded from the Gene Expression Omnibus database. In addition, 46 differentially expressed miRNAs (DEMs) were screened. Then, four miRNAs, including hsa-miR-142-3p, hsa-miR-150, hsa-miR-29b, and hsa-miR-29c, were obtained as prognostic markers by combining univariate Cox regression analysis with weighted gene coexpression network analysis (WGCNA). Subsequently, the risk score of 312 NPC patients from the signature of miRNAs was calculated, and patients were divided into high-risk or low-risk groups. Notably, compared with patients with low-risk scores, high-risk groups had shorter disease-free survival (DFS), overall survival (OS), and distant metastasis-free survival (DMFS). Receiver operating characteristic curve (ROC) analysis indicated that the risk score was a very effective prognostic factor. Moreover, the Search Tool for the Database for Annotation, Visualization, and Integrated Discovery (DAVID), Cytoscape, starBase, and Retrieval of Interacting Genes database (STRING) were used to establish the miRNA-mRNA correlation network and the protein-protein interaction (PPI) network. In addition, the shared genes superimposing 888 protein-coding genes targeted by four hub miRNAs and 1,601 upregulated differentially expressed mRNAs accounted for 127 and were used for subsequent gene functional enrichment analysis. In particular, biological pathway analysis indicated that these genes mainly participate in some vital pathways related to cancer pathogenesis, such as the focal adhesion, PI3K/Akt, p53, and mTOR signalling pathways. In summary, the identification of NPC patients with a four-miRNA signature may increase the prognostic value and provide reference information for precision medicine.

Strand-specific miR-28-3p and miR-28-5p have differential effects on nasopharyngeal cancer cells proliferation, apoptosis, migration and invasion

Background

MicroRNAs (miRNAs) play crucial roles in varieties of cancers, particularly in tumorigenesis, progression, and migration. Dysregulation of miR-28 was reported to occur in various types of human malignancies. In humans, two different mature miRNA sequences are excised from opposite arms of the stem-loop pre-miR-28, hsa-miR-28-3p and hsamiR-28-5p. However, the expression and distinct role of miR-28-3p and miR-28-5p in nasopharyngeal carcinoma (NPC) remain undetermined.

Methods

The expressions of miR-28-3p/-5p in human NPC tissues were tested by quantitative real-time PCR. miR-28-3p/-5p were overexpressed by mimics and silenced by inhibitors. The roles of miR-28-3p/-5p in NPC development were studied using cultured HONE-1 cells.

Results

The mRNA expression levels of miR-28-3p and -5p were significantly decreased in NPC tissues in comparison with adjacent normal tissues. Overexpression of miR-28-5p suppressed NPC cell proliferation and induced cell cycle arrest and apoptosis, while miR-28-3p promoted NPC cell migration and invasion. The miRNAs effected on different signal pathways: miR-28-5p altered expression of cyclin D1 and influenced the PI3K/AKT signaling pathway. In contrast, miR-28-3p downregulated Nm23-H1 and accelerated the process of EMT.

Conclusion

miR-28-3p and -5p were both downregulated in NPC tissues but had distinct biological effects in NPC cells. They may serve as potential prognostic markers and therapeutic targets for NPC.

The targeting of non‑coding RNAs by curcumin: Facts and hopes for cancer therapy (Review)

Curcumin [(1E,6E)-1,7-bis(4-hydroxy-3-methoxyphenyl) hepta-1,6-diene-3,5-dione] is a natural polyphenol that is derived from the turmeric plant (curcuma longa L.). Curcumin is widely used in food coloring, preservatives, and condiments. Curcumin possesses anti-tumor, anti-oxidative and anti-inflammatory efficacy, as well as other pharmacological effects. Emerging evidence indicates that curcumin alters microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) in various types of cancers. Both miRNAs and lncRNAs are non-coding RNAs that can epigenetically modulate the expression of multiple genes via post-transcriptional regulation. In the present review, the interactions between curcumin and non-coding RNAs are summarized in numerous types of cancers, including lung, colorectal, prostate, breast, nasopharyngeal, pancreatic, blood, and ovarian cancer, and the vital non-coding RNAs and their downstream targets are described.

Screening of key miRNAs and evaluation of their diagnostic and prognostic values in nasopharyngeal carcinoma

Increasing evidence has revealed the importance of microRNA (miRNA/miR) in cancer genesis and progression. The aim of the current study was to identify the key miRNAs involved in the onset and development of nasopharyngeal carcinoma (NPC) and to further evaluate their diagnostic and prognostic values. Microarray data were obtained and analyzed to screen differentially expressed miRNAs (DEMs) between patients with NPC and healthy controls. The target genes of the DEMs were predicted and their possible functions were evaluated. The diagnostic and prognostic values of the DEMs were subsequently investigated. A total of 4 DEMs, including miR-18a, miR-135b, miR-204 and miR-497, were identified. Gene Ontology (GO) and pathway enrichment analysis revealed that the target genes were enriched in a number of GO terms and signaling pathways. The results demonstrated that the selected DEMs may present potential diagnostic factors for NPC. In addition, miR-18a [Hazard ratio (HR), 3.405; 95% confidence interval (CI), 1.334-8.693] and miR-135b (HR, 2.482; 95% CI, 1.014-6.076) may serve prognostic roles for patients with NPC. In summary, the present study identified 4 miRNAs that may be involved in the genesis and development of NPC. In addition, miR-18a and miR-135b may present useful prognostic markers for patients with NPC. Future in vitro and in vivo investigations are warranted to substantiate the results obtained in the current study.

PPARβ/δ Agonist GW501516 Inhibits Tumorigenesis and Promotes Apoptosis of the Undifferentiated Nasopharyngeal Carcinoma C666-1 Cells by Regulating miR-206

In previous investigations, we reported that peroxisome proliferator-activated receptor β/δ (PPARβ/δ) activation by GW501516 inhibits proliferation and promotes apoptosis in the undifferentiated C666-1 nasopharyngeal carcinoma (NPC) cells by modulating caspase-dependent apoptotic pathway. In the present study, the mechanism by which GW501516 induces apoptosis was explored from the perspective of microRNA (miRNA) expression. Among the assayed miRNAs that were involved in regulating the expression of antiapoptotic protein Bcl-2, miR-206 was increased significantly and specifically by GW501516 in C666-1 cells at both the in vitro level and at the in vivo xenograft samples. The induction on miR-206 expression caused by GW501516 was capable of being antagonized by the PPARβ/δ antagonist GSK3787 and AMPK antagonist dorsomorphin in C666-1 cells. GW501516's suppression on the growth and apoptosis of C666-1 cells was found to be dependent on the presence of miR-206. miR-206 overexpression resulted in suppressed proliferation and colony formation ability, and further triggered increased apoptosis in C666-1 cells in a caspase-dependent manner. The expression of cleaved caspase 3 and caspase 9, and the ratio of Bax to Bcl-2 were elevated remarkably by miR-206. Consistent with the in vitro result, miR-206 was corroborated to suppress the ectopic NPC xenograft tumorigenesis that derived from the C666-1 cells in BALB/c nu/nu mice. Taken together, the current data demonstrated that miR-206 plays a critical role in the direct apoptosis-promoting effect induced by GW501516 in C666-1 cells. Furthermore, the emphasized tumor-suppressive role of miR-206 in the C666-1 cells indicates that it has the potential to provide a new therapeutic approach for the undifferentiated NPC.

Systematic review and meta-analysis of prognostic microRNA biomarkers for survival outcome in nasopharyngeal carcinoma

BACKGROUND

Nasopharyngeal cancer (NPC), despite being one of the most malignant head and neck carcinomas (HNC), lacks comprehensive prognostic biomarkers that predict patient survival. Therefore, this systematic review and meta-analysis is aimed to evaluate the potential prognostic value of miRNAs as prognostic biomarkers in NPC.

METHODS

PRISMA guidelines were used to conduct this systematic review and meta-analysis study. Permutations of multiple "search key-words" were used for the search strategy, which was limited to articles published between January 2012 and March 2018. The retrieved articles were meticulously searched with multi-level screening by two reviewers and confirmed by other reviewers. Meta-analysis was performed using Hazard Ratios (HR) and associated 95% Confidence Interval (CI) of survival obtained from previously published studies. Publication bias was assessed by Egger's bias indicator test and funnel plot symmetry.

RESULTS

A total of 5069 patients across 21 studies were considered eligible for inclusion in the systematic review, with 65 miRNAs being evaluated in the subsequent meta-analysis. Most articles included in this study originated from China and one study from North Africa. The forest plot was generated using cumulated survival data, resulting in a pooled HR value of 1.196 (95% CI: 0.893-1.601) indicating that the upregulated miRNAs increased the likelihood of death of NPC patients by 19%.

CONCLUSION

To our knowledge, this is the first meta-analysis that examines the prognostic effectiveness of miRNAs as biomarkers in NPC patients. We noted that the combined effect estimate of HR across multiple studies indicated that increased miRNA expression in NPC potentially leads to poor overall survival. However, further large-scale prospective studies on the clinical significance of the miRNAs, with sizable cohorts are necessary in order to obtain conclusive results.

Recent advances in the management of nasopharyngeal carcinoma

Over the last few years, certain areas in the management nasopharyngeal carcinoma (NPC) that have an impact on the care of these patients have evolved, particularly with regard to liquid biopsies, minimally invasive surgery, and advances in chemotherapy and immunotherapy. Beyond its proven role in the diagnostics, surveillance, and treatment of NPC, liquid biopsy with plasma Epstein–Barr virus DNA in the screening of high-risk populations for NPC is strongly supported by recent evidence. Surgery of the nasopharynx is reserved for locally recurrent NPC, and in recent years there have been great strides in minimally invasive techniques with survival rates similar to those of open techniques in treating NPC. Induction chemotherapy in a recent pooled analysis was shown to be superior to concurrent chemotherapy alone for locoregionally advanced NPC. Finally, immunotherapy with a PD-1 inhibitor in NPC has been shown to have 1-year overall survival rates comparable to those of other patients with heavily pre-treated metastatic or recurrent NPC. In this commentary, we discuss these recent advances and their potential in the clinical management of patients with NPC.

Upregulation of circRNA_0000285 serves as a prognostic biomarker for nasopharyngeal carcinoma and is involved in radiosensitivity

Despite significant medical advancement, nasopharyngeal carcinoma (NPC) remains one of the most difficult types of cancer to detect and treat. Circular RNA (circRNA) signatures may be used as prognostic and predictive factors for cancer. Previous studies indicated that the biological role of circular homeodomain interacting protein kinase 3 (HIPK3) has cancer type-specificity. The HIPK3 gene locus formats three circRNA isoforms: circRNA_100783, circRNA_0000285 and circRNA_100782. However, their roles in NPC remain unknown. In the present study, whether these circRNAs could be used as a biomarker for NPC diagnosis and predicting treatment response was investigated. Reverse transcription-quantitative polymerase chain reaction was performed to measure the levels of circRNA_100783, circRNA_0000285 and circRNA_100782 in NPC and adjacent tissues. In addition, the circRNA_0000285 levels were further confirmed in serum samples from patients with NPC and healthy controls. The results demonstrated that circRNA_0000285, but not circRNA_100782 and circRNA_100783, was significantly increased in NPC tissues and serum samples from patients with NPC, compared with adjacent tissues and serum samples from healthy controls, respectively. Furthermore, circRNA_0000285 expression was increased in patients with radioresistant NPC, compared with patients with radiosensitive NPC. Further analysis demonstrated that circRNA_0000285 was significantly associated with tumor size (P<0.001), differentiation (P=0.022), lymph node metastasis (P=0.035), distant metastasis (P=0.022) and Tumor-Node-Metastasis stage (P<0.001). Additionally, univariate and multivariate analyses indicated that circRNA_0000285 may be an independent prognostic factor for the outcome of patients with NPC. The present data indicated that circRNA_0000285 may be a novel biomarker for NPC and is involved in NPC radiosensitivity.

Elevated microRNA-520d-5p in the serum of patients with Parkinson's disease, possibly through regulation of cereloplasmin expression

Iron metabolism dysfunction and redox-active iron-induced oxidative stress in the brain may contribute to the pathogenesis of Parkinson's disease. We have previously demonstrated that reduced serum ceruloplasmin level exacerbates nigral iron deposition in Parkinson's disease, although the underlying cause of the low serum ceruloplasmin level in Parkinson's disease remains unknown. Fluorescent quantitative real-time polymerase chain reaction analysis revealed that patients with Parkinson's disease had higher serum levels of microRNA (miR)-520d-5p than controls (p = 0.0011). Patients with Alzheimer's disease or multiple system atrophy did not have significantly elevated miR-520d-5p levels. Expression of miR-520d-5p did not correlate with disease severity or the motor phenotype of Parkinson's disease. Luciferase assays confirmed that miR-520d-5p was associated with ceruloplasmin gene expression, as predicted by the TargetScan tool and miRBase. In vitro experiments showed that miR-520d-5p reduced ceruloplasmin gene expression in the U251 astrocyte cell line. Our data suggest that miR-520d-5p may be a potential regulator of ceruloplasmin gene expression in vitro.

Dinitrosopiperazine-decreased PKP3 through upregulating miR-149 participates in nasopharyngeal carcinoma metastasis

Nasopharyngeal carcinoma (NPC) has a high metastatic clinicopathological feature. As a carcinogen factor, N,N'-dinitrosopiperazine (DNP) is involved in NPC metastasis, but its precise mechanism has not been fully elucidated. Herein, we showed that DNP promotes NPC metastasis through upregulating miR-149. DNP was found to decrease Plakophilin3 (PKP3) expression, further DNP-decreased PKP3 was verified to be through upregulating miR-149. We also found that DNP induced proliferation, adhesion, migration and invasion of NPC cell, which was inhibited by miR-149-inhibitor. DNP may promote NPC metastasis through miR-149-decreased PKP3 expression. Therefore, DNP-increased miR-149 expression may be an important factor of NPC high metastasis, and miR-149 may serve as a molecular target for anti-metastasis therapy of NPC.

Comparison of 18F-NaF PET/CT and 18F-FDG PET/CT for Detection of Skull-Base Invasion and Osseous Metastases in Nasopharyngeal Carcinoma

Our study aimed at comparing the diagnostic value of 18F-NaF positron emission tomography-computed tomography (PET/CT) and 18F-fluorodeoxyglucose (FDG) PET/CT for detection of skull-base invasion and osseous metastases in patients with nasopharyngeal carcinoma (NPC). Our study retrospectively analyzed 45 patients with pathologically proven NPC. They all underwent both 18F-NaF PET/CT and 18F-FDG PET/CT within a 7-day interval. Bone metastases were confirmed by follow-up using PET/CT, enhance-contrast computed tomography (CT), and magnetic resonance image (MRI). These two examinations were compared using per-patient-based analysis and per-lesion-based analysis. 18F-NaF PET/CT detected 27 patients with skull-base invasion, whereas 18F-FDG PET/CT detected 17 patients. 18F-NaF PET/CT and 18F-FDG PET/CT differed significantly in diagnosing skull-base invasion (p=0.02) and sensitivity (p=0.008). The sensitivity, specificity, and agreement rate of 18F-NaF PET/CT for detecting bone metastatic lesions were 98.3%, 65.7%, and 92.9%, respectively; these values were 42.9%, 97.1%, and 51.9%, respectively, for 18F-FDG PET/CT. 18F-NaF PET/CT and 18F-FDG PET/CT differed significantly in the number of osseous metastases detected (t=2.45, p=0.18) sensitivity (p < 0.0001) and specificity (p=0.003). In patients with nasopharyngeal carcinoma, 18F-NaF PET/CT assessed invasion of the skull base better and detected more osseous metastases than 18F-FDG PET/CT.

MicroRNA-328 inhibits migration and epithelial-mesenchymal transition by targeting CD44 in nasopharyngeal carcinoma cells

Background

MicroRNAs (miRNAs) play crucial roles in various types of cancers, particularly in tumor development, migration, and progression. Dysregulation of miR-328 was reported to occur in some types of human malignancies, however, the role of miR-328 in nasopharyngeal carcinoma (NPC) and its potential involvement in metastasis remain undetermined.

Methods

The invasion capacity of NPC sphere-forming cells was evaluated by in vitro cell migration assays. Differential miRNAs expression was examined in NPC sphere-forming cells compared to parental monolayer cells using miRNA array analysis. The role of miR-328 in regulating NPC cells migratory properties was analyzed after miR-328 mimics transfection. The expression of E-cadherin and CD44 was analyzed by flow cytometry. CD44 was examined as a target of miR-328 through luciferase reporter assays and Western blotting.

Results

Here, we report that NPC TW01 and TW06 sphere-forming cells exhibited increased migratory ability in comparison with parental monolayer cells. Sphere-forming cells had significantly lower levels of miR-328, as observed using miRNA arrays and confirmed through real-time polymerase chain reaction. Overexpression of miR-328 induced by transfection with synthetic miR-328 mimics decreased the migration of NPC sphere-forming cells. The inhibitory effects were associated with increased expression of E-cadherin and the downregulated expression of mesenchymal markers such as N-cadherin, Snail, and vimentin. Moreover, our results demonstrated that miR-328 suppressed NPC cell migration and inhibited the epithelial–mesenchymal transition process directly through a binding site on the CD44 3′ untranslated region.

Conclusion

miR-328, a previously unrecognized miRNA, may serve as a potential prognostic marker and therapeutic target for NPC.

Abnormally expressed microRNA as auxiliary biomarkers for nasopharyngeal carcinoma: A meta-analysis

Aberrant expression of microRNA (miRNA) has been highlighted as a helpful indicator to aid in nasopharyngeal carcinoma (NPC) diagnosis. The present meta-analysis aimed to validate the efficacy of miRNA as potential biomarkers for NPC detection. Publication searches were conducted on the online PubMed and EMBASE databases from inception to June 2016. A bivariate meta-analysis was performed to generate the diagnostic parameters based on Meta-Disc 1.4 and Stata 12.0 programs. Sensitivity analysis and meta-regression tests were applied to trace heterogeneity sources among eligible studies. A total of six studies comprising 528 patients with NPC and 252 matched controls were enrolled. Results from the present meta-analysis demonstrated that miRNA testing achieved a pooled sensitivity of 0.78 [95% confidence interval (CI), 0.70-0.84] and specificity of 0.79 (95% CI, 0.73-0.84) in confirming NPC, corresponding to an area under the curve (AUC) value of 0.85. Additionally, the pooled diagnostic odds ratio was estimated to be 9.01 (95% CI, 5.62-14.44), along with a positive likelihood ratio of 2.81 (95% CI, 2.19-3.61) and negative likelihood ratio of 0.35 (95% CI, 0.28-0.44). Additionally, the stratified analyses revealed that paralleled testing of miRNA sustained a pooled accuracy superior compared with that of single miRNA testing (sensitivity, 0.88 vs. 0.70; specificity, 0.85 vs. 0.69; AUC, 0.95 vs. 0.75). Testing of miRNA harbors a moderate diagnostic efficacy and is acceptable as an auxiliary biomarker for NPC diagnosis.

MALAT1/miR-124/Capn4 axis regulates proliferation, invasion and EMT in nasopharyngeal carcinoma cells

BACKGROUND

Long non-coding RNA MALAT1 (Metastasis-associated lung Adenocarcinoma transcript-1) has been demonstrated to play a critical role in the regulation of cancer progression and metastasis. However, little is known about MALAT1 in nasopharyngeal carcinoma (NPC) pathogenesis and progression.

METHODS

Quantitative real-time PCR (qRT-PCR) was conducted to measure the expression of MALAT1, miR-124 and Capn4 mRNA in NPC cell lines. The protein level of Capn4 was examined by western blot analysis. Cell proliferation was detected by MTT assay, trypan blue exclusion method and colony formation analysis. Cell invasion was determined by transwell chamber assay. Expression of EMT-related proteins was detected by western blot. The potential targets of MALAT1 and miR-124 were verified by target prediction and luciferase reporter assay.

RESULTS

MALAT1 and Capn4 were upregulated while miR-124 expression was downregulated in NPC cell lines. MALAT1 knockdown inhibited proliferation, invasion and EMT of NPC cells. Moreover, MALAT1 improved Capn4 expression by sponging miR-124. MALAT1 upregulation abated miR-124-induced repression on NPC cell proliferation, invasion and EMT. Furthermore, Capn4 overexpression reversed the inhibitory effect of MALAT1 silencing on proliferation, invasion and EMT of NPC cells.

CONCLUSION

MALAT1 promoted proliferation, invasion and EMT of NPC cells through de-repressing Capn4 by sponging miR-124. The present study revealed a novel MALAT1/miR-124/Capn4 regulatory axis in NPC, contributing to a better understanding of the NPC pathogenesis and providing a promising therapeutic target for NPC therapy.

Over-expression of protein tyrosine phosphatase 4A2 correlates with tumor progression and poor prognosis in nasopharyngeal carcinoma

Protein tyrosine phosphatase 4A2 (PTP4A2) has been implicated as an oncogenic protein in several human cancers. However, the level of PTP4A2 expression and its prognostic significance in nasopharyngeal carcinoma (NPC) remains unknown. In this study, Western blotting (WB), quantitative real-time PCR (qT-PCR) and immunohischemistry (IHC) was applied to evaluated the expression levels of PTP4A2 in NPC cell lines and tumor tissues combining two independent cohorts. Receiver-operator curve (ROC) analysis was used to assessed the optimal cut-off score in training cohort (266 cases). This cut-off score was subjected to determine the association of PTP4A2 expression with patients’ clinical characteristics and survival outcome in the validation cohort (201 cases) and the overall population (467 cases). We found that PTP4A2 were significantly overexpressed in NPC cell lines compared with normal nasopharyngeal epithelial cell. Moreover, overexpression of PTP4A2 was positively correlated with advanced T classification (P<0.001) and TNM stages (P<0.001). And higher PTP4A2 expression was an independent prognostic factor for adverse overall survival (P<0.05) and poor disease-free survival (P<0.05). Our results demonstrated that the overexpression of PTP4A2 was closely associated with poor survival outcome in patients with NPC and may represent a novel prognostic biomarker and therapeutic target for this disease.