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DNA methylation is an important epigenetic change in carcinogenesis. However, the function and mechanism of DNA methylation dysregulation in nasopharyngeal carcinoma (NPC) is still largely unclear. Our previous genome-wide microarray data showed that NFAT1 is one of the most hypermethylated transcription factor genes in NPC tissues. Here, we found that NFAT1 hypermethylation contributes to its down-regulation in NPC. NFAT1 overexpression inhibited cell migration, invasion, and epithelial-mesenchymal transition in vitro and tumor metastasis in vivo. We further established that the tumor suppressor effect of NFAT1 is mediated by its inactivation of ITGA6 transcription. Our findings suggest the significance of activating NFAT1/ITGA6 signaling in aggressive NPC, defining a novel critical signaling mechanism that drives NPC invasion and metastasis and providing a novel target for future personalized therapy.

Altered DNA methylation is a key feature of cancer, and aberrant methylation is important in nasopharyngeal carcinoma (NPC) development. However, the methylation mechanisms underlying metastasis of NPC remain unclear. Analyzing data from public databases and conducting our own experiments, we report here that promoter hypermethylation of SHISA3 is common and contributes to the downregulation of this gene in many types of tumors, including NPC. SHISA3 suppressed NPC cell invasion and metastasis in vitro and in vivo by impeding the E3 ubiquitin ligase tripartite motif containing 21 (TRIM21)–mediated ubiquitination and degradation small G protein signaling modulator 1 (SGSM1) and by inhibiting the MAPK pathway activation. Silencing SGSM1 abrogated the inhibitory effect of SHISA3 on NPC cell migration and invasion. This newly identified SHISA3–TRIM21–SGSM1 axis could be a novel therapeutic target in NPC. Significance: These findings highlight the mechanism by which a newly identified tumor suppressor SHISA3 suppresses invasion and metastasis of nasopharyngeal carcinoma.

Background The Leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5), which is used as a marker of adult stem cells and colorectal cancer stem cells (CSCs), is closely associated with the progression of non-small cell lung cancer (NSCLC). This study aimed to identify the clinical significance and biological function of LGR5 in NSCLC. Methods Quantitative reverse transcription polymerase chain reaction (RT-PCR) was applied to detect the expression of LGR5 and stemness-related genes in 22 NSCLC patients, and the clinical significance of LGR5 in NSCLC progression was estimated by statistical analysis. LGR5 overexpressing A549- and H1299-transfected cells were established, and CCK-8 and clone formation assays were used to test the proliferation ability. A wound-healing assay was utilized to clarify the migration ability. The invasion ability was confirmed via the Transwell assay kit. Results LGR5 expression was markedly higher in NSCLC tissues than in the matched adjacent normal tissues, and had a trend to associate with tumor size, lymph node metastasis, and TNM stage. The proliferation rates, clone formation rates, wound healing rates, number of invasive cells, and the NOTCH1 expression of the LGR5 overexpressing groups, were significantly higher than those of the control groups. Conclusions LGR5 plays an essential role in NSCLC tumorigenesis and is closely associated with the proliferation, metastasis, and invasion of NSCLC cells. LGR5 may promote NSCLC progression via NOTCH1 and could be a new target for gene-targeted therapies for NSCLC.

B7-H3, one of the costimulatory members participating in checkpoint pathway, has been shown to be upregulated after hepatitis B virus (HBV) infection. To further explore the clinical significance of dynamic B7-H3 expression during the progression of HBV infection, we systematically investigated the expression pattern of B7-H3 and the correlation of B7-H3 expression with the ratio of T lymphocyte subsets and clinical parameters at different stages in the course of the disease. Flow cytometry and enzyme-linked immunosorbent assay data showed that soluble form of B7-H3 (sB7-H3) was positively correlated with the frequency of Treg cells in acute hepatitis B (AHB), chronic hepatitis B (CHB), and hepatocellular carcinoma patients with HBV infection (HBV-HCC). Membrane form of B7-H3 (mB7-H3) expressed on Treg cells and monocytes was positively correlated with the frequency of Treg cells in CHB. SB7-H3 had relationship with mB7-H3 expressed on Treg cells and monocytes at different stages during HBV infection, except for HBV-HCC. MB7-H3 expressed on Treg cells was positively correlated with that on monocytes in AHB, CHB, HBV-liver cirrhosis, and HBV-HCC. The B7-H3 expression was positively correlated with aspartate aminotransferase and alanine aminotransferase levels in CHB and sB7-H3 level was higher in late tumor/node/metastasis (TNM) stage in HCC. Higher mB7-H3 expression was associated with greater tumor size, later TNM stage, and worse prognosis in HBV-HCC indicated by immunohistochemistry. Taken together, these results suggested that B7-H3 might contribute to the progression of HBV infection by triggering inhibitory signals in effector T cells and it was closely associated with the progression and poor prognosis during HBV infection. B7-H3 could be utilized as a potential clinical indicator and a potential target for therapeutic strategies against HBV infection.

Objectives: Clinical benefits of immune-checkpoint blockade (ICB) versus standard chemotherapy have been established in unselected non-small cell lung cancer (NSCLC). However, the response to ICB therapy among patients is heterogeneous in clinical practice. Materials and Methods: We retrospectively assessed the predicitive effect of the primary and metastatic lesion spectrum (baseline sum of the longest diameters [SLD], number of metastatic sites and specific organ metastases) on the efficacy of atezolizumab over docetaxel in OAK and POPLAR trial cohorts. A decision model, termed DSO (Diameter-Site-Organ), based on the spectrum was developed and validated for guiding ICB. Results: Higher SLD (>38 mm) and more metastatic sites (≥2) were characterized with pronounced overall survival (OS) benefits from atezolizumab versus docetaxel. Specifically, adrenal gland and brain metastases were identified as favorable predictors of atezolizumab treatment. The DSO model was developed in the discovery cohort to integrate the directive effect of the primary and metastatic lesion spectrum. Remarkably, a general pattern of enhanced efficacy of atezolizumab versus docetaxel was observed along with the increase of the DSO score. For patients with DSO score > 0, atezolizumab yielded a significantly prolonged OS than docetaxel, whereas OS was generally similar between two treatments in patients with DSO score ≤ 0. Equivalent findings were also seen in the internal and external validation cohorts. Conclusions: The response to anti-PD-L1 therapy among patients varied with the primary and metastatic lesion spectrum. The DSO-based system might provide promising medication guidance for ICB treatment in NSCLC patients.

Percutaneous ethanol injection is a well-known ablation therapy for hepatocellular carcinoma and is well-tolerated, inexpensive, and effective with few adverse events. In this study, another type of ethanol injection was introduced in the present study. Sixty two patients with hepatocellular carcinoma received 133 percutaneous peritumor ethanol injection treatments and the 15-year follow-up outcomes were analyzed through a collected database. The technical efficiency was 89.5% (119/133 treatments) after the first percutaneous peritumor ethanol injection procedure. However, after the second repeated percutaneous peritumor ethanol injection procedure, technical efficiency increased to 98.5% (131/133 treatments). The 1 year, 3 years, 5 years, 10 years, and 15 years rates of tumor recurrence were 12.9%, 50.0%, 59.7%, 74.2%, and 74.2%, respectively. Multivariate analysis demonstrated that diabetes, Child–Pugh class B, and tumor size greater than 2 cm were significantly related to tumor recurrence. The 1 year, 3 years, 5 years, 10 years, and 15 years rates of overall survival were 98.4%, 83.6%, 61.3%, 19.4%, and 0%, respectively. Multivariate analysis demonstrated that Child–Pugh class B, tumor size greater than 2 cm, and multiple tumors were significantly related to overall survival. Compared with other ablation methods (including peritumor ethanol injection), percutaneous peritumor ethanol injection can avoid tumor ruptures, reduce tumor proliferation and metastasis, and is suitable for the treatment of small tumors. In addition, when combined with other treatment methods, percutaneous peritumor ethanol injection can form a tumor metastatic isolation zone in advance and improve the comprehensive treatment effect.

Background Increasing evidence recognizes that DNA methylation abnormalities play critical roles in cancer development. Our previous genome-wide methylation profile showed that tumor necrosis factor-alpha-induced protein 8 like 3 (TIPE3) was hypermethylated in nasopharyngeal carcinoma (NPC). However, the relationship between TIPE3 methylation and its mRNA expression, as well as its biological roles in NPC are unknown. Methods Bisulfite pyrosequencing and quantitative RT-PCR were performed to quantify the TIPE3 methylation and expression levels. Kaplan-Meier curves and Cox regression analysis were used to estimate the correlation between TIPE3 methylation levels and survival in two patient cohorts collected from two hospitals (n = 441). The MTT, colony formation, Transwell migration and invasion assays, and xenograft tumor growth and lung metastatic colonization models were used to identify the functions of TIPE3 on NPC cells. Results We found that TIPE3 CpG island (CGI) was hypermethylated and its mRNA levels were downregulated in many cancers, including NPC. TIPE3 downregulation was associated with its CGI hypermethylation. Furthermore, NPC patients with high TIPE3 CGI methylation levels had poorer clinical outcomes than those with low methylation levels. The TIPE3 CGI methylation level was an independent prognostic factor. Moreover, restoring TIPE3 expression significantly inhibited NPC cell proliferation, migration and invasion in vitro, and suppressed tumor growth and lung metastatic colonization in vivo, while silencing TIPE3 acted in an opposite way. Conclusions TIPE3 downregulation correlates with its CGI hypermethylation in several solid cancers. TIPE3 acts as a tumor suppressor in NPC, providing a further insight into NPC progression and representing a potential prognostic biomarker for NPC. Electronic supplementary material The online version of this article (10.1186/s13046-018-0881-5) contains supplementary material, which is available to authorized users.

Purpose: Epigenetic alterations play important roles in metastasis and drug resistance through gene regulation. However, the functional features and molecular mechanisms of epigenetic changes remain largely unclear in nasopharyngeal carcinoma (NPC) metastasis. Experimental Design: Gene regulatory network analysis was used to identify metastatic-specific dysregulated genes between normal and NPC tissues and the expression was validated in published Gene-Expression Omnibus data set. The regulatory and functional role of RAB37 downregulation was examined in NPC and was validated in vitro and in vivo, and downstream target of RAB37 was explored. The clinical value of RAB37 methylation was evaluated in NPC metastasis and chemosensitivity. Results: We identified RAB37 as a specific hypermethylated gene that is most commonly downregulated in NPC. Moreover, RAB37 downregulation was attributed to hypermethylation of its promoter and was significantly associated with metastasis- and docetaxel chemoresistance-related features in NPC. Ectopic RAB37 overexpression suppressed NPC cell metastasis and enhanced chemosensitivity to docetaxel. Mechanistically, RAB37 colocalized with TIMP2, regulated TIMP2 secretion, inhibited downstream MMP2 activity, and consequently altered NPC cell metastasis. Furthermore, RAB37 hypermethylation was correlated with poor clinical outcomes in patients with NPC. We developed a prognostic model based on RAB37 methylation and N stage that effectively predicted an increased risk of distant metastasis and a favorable response to docetaxel-containing induction chemotherapy (IC) in NPC patients. Conclusions: This study shows that RAB37 hypermethylation is involved in NPC metastasis and chemoresistance, and that our prognostic model can identify patients who are at a high risk of distant metastasis and might benefit from for docetaxel IC.

Nasopharyngeal carcinoma (NPC) is characterized by a high rate of local invasion and early distant metastasis. Increasing evidence indicates that epigenetic abnormalities play important roles in NPC development. However, the epigenetic mechanisms underlying NPC metastasis remain unclear. Here we investigate aberrantly methylated transcription factors in NPC tissues, and we identify the HOP homeobox HOPX as the most significantly hypermethylated gene. Consistently, we find that HOXP expression is downregulated in NPC tissues and NPC cell lines. Restoring HOPX expression suppresses metastasis and enhances chemosensitivity of NPC cells. These effects are mediated by HOPX-mediated epigenetic silencing of SNAIL transcription through the enhancement of histone H3K9 deacetylation in the SNAIL promoter. Moreover, we find that patients with high methylation levels of HOPX exhibit poor clinical outcomes in both the training and validation cohorts. In summary, HOPX acts as a tumour suppressor via the epigenetic regulation of SNAIL transcription, which provides a novel prognostic biomarker for NPC metastasis and therapeutic target for NPC treatment., HOPX is a transcription factor epigenetically silenced in several cancers. Here the authors, by analysing methylation profiles, identify HOPX as a suppressor of metastasis in nasopharyngeal carcinoma: mechanistically HOPX inhibits SNAIL transcription through deacetylation-mediated silencing.

Dysregulation of miRNAs has been shown to contribute to the carcinogenesis and progression of nasopharyngeal carcinoma (NPC). Our previous microarray data showed that miR-16 expression is significantly decreased in archived NPC tissues. Here, we confirmed that miR-16 was reduced in NPC cell lines and freshly-frozen samples. Ectopic expression of miR-16 suppressed NPC cell proliferation, migration, and invasion in vitro and inhibited tumor growth and metastatic colonization in the lung in vivo. Furthermore, fibroblast growth factor 2 (FGF2) was identified as a direct target of miR-16, and both phosphoinositide-3- kinase/AKT (PI3K/AKT) and mitogen-activated protein kinase (MAPK) signaling pathways were repressed after miR-16 overexpression. In addition, the restoration of FGF2 reversed the suppressive effects of miR-16. Together, these results indicated that miR-16 suppresses NPC carcinogenesis and progression by targeting FGF2, thereby representing a potential target for miRNA-based therapy for NPC in the future.

Human nasopharyngeal carcinoma (NPC) has the highest metastatic rate in head and neck. However, the mechanisms underlying NPC metastasis remain unclear. Here using propensity-score-matched miRNA microarray analysis, miR-142-3p is identified to be the most correlated with distant-metastasis-free survival and downregulated in paraffin-embedded NPC with distant metastasis, which is validated in both internal cohort and external GEO dataset from Canada. miR-142 locus hypermethylation was observed and found to be associated with miR-142-3p downregulation in metastatic NPC. Furthermore, miR-142-3p was epigenetically silenced by EZH2-recruited DNMT1 and suppressed NPC cell metastasis and EMT. Intersecting PCR array gene profiling with bioinformatic prediction, we identify ZEB2 as a direct and functional target of miR-142-3p in NPC. Reversal of miR-142-3p silencing efficiently suppresses NPC cell invasion and metastasis. Moreover, epigenetic miR-142 hypermethylation is correlated with unfavorable prognosis in both training and validation cohorts. This study identifies miR-142-3p as a key suppressive regulator in NPC metastasis and reveals a DNMT1-mediated epigenetic mechanism for miR-142-3p silencing, providing a potential prognostic marker and therapeutic target to combat NPC metastasis.

Distant metastasis remains the predominant mode of treatment failure in nasopharyngeal carcinoma (NPC). Unfortunately, the molecular events underlying NPC metastasis remain poorly understood. Secreted frizzled-related protein 1 (SFRP1) plays an important role in tumorigenesis and progression. However, little is known about the function and mechanism of SFRP1 in NPC. Immunohistochemistry was used to determine SFRP1 expression levels in patients with NPC. SFRP1 function was evaluated using MTT, colony formation, wound-healing, Transwell assays, and in vivo models. The methylation level of SFRP1 in NPC cells was examined using bisulfate pyrosequencing; the Wnt/β-catenin signaling pathway genes were studied using Western blotting. Compared with patients with high SFRP1 expression, patients with low SFRP1 expression had worse overall survival [HR, 2.32; 95% confidence interval (CI), 1.36–3.94; P = 0.002], disease-free survival (HR, 1.98; 95% CI, 1.23–3.18; P = 0.005), and distant metastasis-free survival (HR, 2.07; 95% CI, 1.19–3.59; P = 0.009). Multivariate Cox regression analysis indicated that SFRP1 was an independent prognostic factor. Furthermore, SFRP1 was significantly downregulated in NPC cell lines. SFRP1 overexpression suppressed NPC cell proliferation, migration, and invasion in vitro and lung colonization in vivo. SFRP1 expression was restored after treatment with a demethylation agent, and the SFRP1 promoter region was hypermethylated in NPC cells. β-Catenin, c-Myc, and cyclin D1 were downregulated after SFRP1 restoration, which suggested that SFRP1 suppressed growth and metastasis by inhibiting the Wnt/β-catenin signaling pathway in NPC. SFRP1 provides further insight into NPC progression and may provide novel therapeutic targets for NPC treatment. Cancer Prev Res; 8(10); 968–77. ©2015 AACR.

This study assessed the incidence and prognostic value of MET protein overexpression and gene amplification in locoregionally advanced nasopharyngeal carcinoma (NPC). Specimens from 376 consecutive patients with locoregionally advanced NPC were subjected to immunohistochemistry to analyze MET protein expression and fluorescence in situ hybridization to assess MET amplification status. In total, 139/376 (37.0%) patients had MET protein overexpression; of whom, 7/139 (5.0%) had MET amplification. MET overexpression was significantly associated with locoregional failure (P = 0.009), distant metastasis (P = 0.006) and death (P < 0.001); MET amplification was significantly associated with death (P = 0.021). A positive correlation was observed between MET copy number status and MET protein expression (r = 0.629, P < 0.001). Multivariate analysis demonstrated MET overexpression was an independent prognostic factor for overall survival (OS; HR, 1.99; 95% CI, 1.38–2.87; P < 0.001) and disease-free survival (DFS; HR, 1.85; 95% CI, 1.33–2.57; P < 0.001), and MET amplification was independently associated with poorer OS (HR, 4.24; 95% CI, 1.78-10.08; P < 0.001) and DFS (HR, 5.44; 95% CI, 2.44-12.09; P < 0.001). In conclusion, MET protein overexpression and gene amplification are independent prognostic factors for OS and DFS in locoregionally advanced nasopharyngeal carcinoma, and may provide therapeutic biomarkers to identify patients in whom MET inhibitors may be beneficial.

Background Based on our recent microarray analysis, we found that miR-145 was obviously downregulated in nasopharyngeal carcinoma (NPC) tissues. However, little is known about its function and mechanism involving in NPC development and progression. Methods Quantitative RT-PCR was used to detect miR-145 expression in NPC cell lines and clinical samples. Wound healing, Transwell migration and invasion, three-dimension spheroid invasion assays, and lung metastasis model were performed to test the migratory, invasive, and metastatic ability of NPC cells. Luciferase reporter assay, quantitative RT-PCR, and Western blotting were used to verify the target of miR-145. Results MiR-145 was obviously decreased in NPC cell lines and clinical samples (P

Clinically, distant metastasis after primary treatment remains a key problem in nasopharyngeal carcinoma (NPC), and the treatment outcome of metastatic NPC remains disappointing, so there is a pressing need to identify novel therapeutic strategies. In accordance with our previous microarray data, we found that miR-101 was downregulated in NPC clinical specimens and cell lines. Ectopic expression of miR-101 significantly suppressed NPC cell migration, invasion and angiogenesis in vitro and inhibited angiogenesis and metastasis in vivo using the chicken chorioallantoic membrane model. Furthermore, ITGA3 was identified and validated as a novel target of miR-101, and the restoration of ITGA3 expression potently rescued the suppressive effects of miR-101. In addition, NPC patients with high ITGA3 expression had poorer overall survival and distant metastasis-free survival than patients with low ITGA3 expression, and ITGA3 overexpression was an independent poor prognostic factor in NPC. More importantly, we demonstrated that the systemic delivery of lentivirus-mediated miR-101 abrogated the lung metastatic colonization formation of NPC cells without obvious toxicity. Our study elucidates the molecular mechanisms of miR-101/ITGA3 pathway in regulating NPC metastasis and angiogenesis, and the systemic delivery of miR-101 provides a potent evidence for the development of a novel microRNA-targeting anticancer strategy for NPC patients.

Increasing evidence has demonstrated a significant role for long non-coding RNAs (lncRNAs) in tumorigenesis. However, their functions in nasopharyngeal carcinoma (NPC) metastasis remain largely unknown. In this study, a model comparing high and low metastatic NPC cell lines (5-8F vs. 6-10B and S18 vs. S26) was constructed to determine the expression profile of lncRNAs using the microarray analysis, and we found 167 lncRNAs and 209 mRNAs were differentially expressed. Bioinformatic analysis indicated that the dysregulated mRNAs participated in important biological regulatory functions in NPC. Validation of 26 significantly dysregulated lncRNAs by qRT-PCR showed the expression patterns of 22 lncRNAs were in accordance with the microarray data. Furthermore, the expression level of ENST00000470135, which was the most upregulated lncRNA in high metastatic cell lines, was significantly higher in NPC cell lines and tissues with lymph node metastasis (LNM) and knocking down ENST00000470135 suppressed the migration, invasion and proliferation of NPC cells in vitro. In conclusion, our study revealed expression patterns of lncRNAs in NPC metastasis. The dysregulated lncRNAs may act as novel biomarkers and therapeutic targets for NPC.

Background Talin-1 is a cytoskeletal protein that plays an important role in tumourgenesis, migration and metastasis in several malignant tumors. The aim of this study was to evaluate the expression and prognostic value of Talin-1 in nasopharyngeal carcinoma (NPC). Methods Talin-1 mRNA and protein expression were examined in NPC cell lines and clinical nasopharyngeal tissues by quantitative RT-PCR, agarose gel electrophoresis and western blotting. The expression of Talin-1 was analyzed by immunohistochemical staining in 233 paraffin-embedded NPC specimens with clinical follow-up data and cox regression analysis was used to identify independent prognostic factors. The functional role of Talin-1 in NPC cell lines was evaluated by small interfering RNA-mediated depletion of the protein followed by the wound healing and transwell invasion assays. Results The expression of Talin-1 was significantly upregulated in most NPC cell lines and clinical tissues at both the mRNA and protein levels. High expression of Talin-1 was significantly associated with distant metastasis (P = 0.001) and patient death (P = 0.001). In addition, high expression of Talin-1 was associated with significantly poorer overall survival (OS: HR, 2.15; 95% CI, 1.28-3.63; P = 0.003) and poorer distant metastasis-free survival (DMFS: HR, 2.39; 95% CI, 1.38-4.15; P = 0.001). Cox regression analysis indicated that high expression of Talin-1 and TNM stage were independent prognostic indicators (both P

Background Metastasis remains the major cause of death in nasopharyngeal carcinoma (NPC). Yippee-like 3 (YPEL3) plays an important role in tumorigenesis. However, its function and mechanism in NPC has not been systematically explored. Methods We evaluated YPEL3 expression in NPC cell lines and tissues using real-time PCR and western blotting. Then, we established NPC cell lines that stably overexpressed YPEL3 and knocked down YPEL3 expression to explore its function in NPC in vitro and in vivo. Additionally, we investigated the potential mechanism of YPEL3 action by identifying the Wnt/β-catenin signaling pathway downstream genes using western blotting. Results YPEL3 was downregulated in NPC cell lines and tissue samples. Ectopic expression of YPEL3 inhibited NPC cell migration and invasion in vitro; while silencing of YPEL3 promoted NPC cell migration and invasion. Further study indicated that overexpression of YPEL3 inhibited NPC cell epithelial–mesenchymal transition (EMT) and that silencing it enhanced EMT. Overexpression of YPEL3 suppressed NPC cell lung metastasis in vivo. The mechanism study determined that YPEL3 suppressed the expression levels of Wnt/β-catenin signaling pathway downstream genes and the nuclear translocation of β-catenin. Conclusions YPEL3 suppresses NPC EMT and metastasis by suppressing the Wnt/β-catenin signaling pathway, which would help better understanding the molecular mechanisms of NPC metastasis and provide novel therapeutic targets for NPC treatment.