Gemcitabine synergizes with cisplatin to inhibit nasopharyngeal carcinoma cell proliferation and tumor growth.

In a recently published phase III clinical trial, gemcitabine (GEM) plus cisplatin (DDP) induction chemotherapy significantly improved recurrence-free survival and overall survival and became the standard of care among patients with locoregionally advanced NPC. However, the molecular mechanisms of GEM synergized with DPP in NPC cells remain elucidated. These findings prompt us to explore the effect of the combination between GEM and DDP in NPC cell lines through proliferative phenotype, immunofluorescence, flow cytometry, and western blotting assays. In vitro studies reveal that GEM or DPP treated alone induces cell cycle arrest, promotes cell apoptosis, forces DNA damage response, and GEM synergism with DDP significantly increases the above effects in NPC cells. In vivo studies indicate that GEM or DPP treated alone significantly inhibits the tumor growth and prolongs the survival time of mice injected with SUNE1 cells compared to the control group. Moreover, the mice treated with GEM combined with DDP have smaller tumors and survive longer than those in GEM or DPP treated alone group. In addition, P-gp may be the key molecule that regulates the synergistic effect of gemcitabine and cisplatin. GEM synergizes with DPP to inhibit NPC cell proliferation and tumor growth by inducing cell cycle arrest, cell apoptosis, and DNA damage response, which reveals the mechanisms of combined GEM and DDP induction chemotherapy in improving locoregionally advanced NPC.

Unraveling tumour microenvironment heterogeneity in nasopharyngeal carcinoma identifies biologically distinct immune subtypes predicting prognosis and immunotherapy responses.

Currently, there is no strong evidence of the well-established biomarkers for immune checkpoint inhibitors (ICIs) in nasopharyngeal carcinoma (NPC). Here, we aimed to reveal the heterogeneity of tumour microenvironment (TME) through virtual microdissection of gene expression profiles. An immune-enriched subtype was identified in 38% (43/113) of patients, which was characterized by significant enrichment of immune cells or immune responses. The remaining patients were therefore classified as a non-Immune Subtype (non-IS), which exhibited highly proliferative features. Then we identified a tumour immune evasion state within the immune-enriched subtype (18/43, 42%), in which high expression of exclusion- and dysfunction-related signatures was observed. These subgroups were designated the Evaded and Active Immune Subtype (E-IS and A-IS), respectively. We further demonstrated that A-IS predicted favourable survival and improved ICI response as compared to E-IS and non-IS. In summary, this study introduces the novel immune subtypes and demonstrates their feasibility in tailoring immunotherapeutic strategies.

FNDC3B 3'-UTR shortening escapes from microRNA-mediated gene repression and promotes nasopharyngeal carcinoma progression.

Alternative polyadenylation (APA), which induces shortening of the 3'-UTR, is emerging as an important feature in cancer development and progression. Nevertheless, the effects and mechanisms of APA-induced 3'-UTR shortening in nasopharyngeal carcinoma (NPC) remain largely unclear. Fibronectin type III domain containing 3B (FNDC3B) tended to use proximal polyadenylation site and produce shorter 3'-UTR according to our previous sequencing study. Herein, we found that FNDC3B with shorter 3'-UTR could escape from miRNA-mediated gene repression, and caused its increased expression in NPC. Knocking down of FNDC3B inhibited NPC cell proliferation, migration, invasion, and metastasis in vitro and in vivo. Overexpression of FNDC3B, especially those with shorter 3'-UTR, promoted NPC progression. Furthermore, the mechanism study revealed that FNDC3B could bind to and stabilize myosin heavy chain 9 (MYH9) to activate the Wnt/ß-catenin signaling pathway. In addition, MYH9 could reverse the inhibitory effects of FNDC3B knockdown in NPC. Altogether, our results suggested that the 3'-UTR shortening of FNDC3B mRNA mediated its overexpression in NPC and promoted NPC progression by targeting MYH9. This newly identified FNDC3B-MYH9-Wnt/ß-catenin axis could represent potential targets for individualized treatment in NPC.

Development and validation of a gene expression-based signature to predict distant metastasis in locoregionally advanced nasopharyngeal carcinoma: a retrospective, multicentre, cohort study.

BACKGROUND: Gene expression patterns can be used as prognostic biomarkers in various types of cancers. We aimed to identify a gene expression pattern for individual distant metastatic risk assessment in patients with locoregionally advanced nasopharyngeal carcinoma. METHODS: In this multicentre, retrospective, cohort analysis, we included 937 patients with locoregionally advanced nasopharyngeal carcinoma from three Chinese hospitals: the Sun Yat-sen University Cancer Center (Guangzhou, China), the Affiliated Hospital of Guilin Medical University (Guilin, China), and the First People's Hospital of Foshan (Foshan, China). Using microarray analysis, we profiled mRNA gene expression between 24 paired locoregionally advanced nasopharyngeal carcinoma tumours from patients at Sun Yat-sen University Cancer Center with or without distant metastasis after radical treatment. Differentially expressed genes were examined using digital expression profiling in a training cohort (Guangzhou training cohort; n=410) to build a gene classifier using a penalised regression model. We validated the prognostic accuracy of this gene classifier in an internal validation cohort (Guangzhou internal validation cohort, n=204) and two external independent cohorts (Guilin cohort, n=165; Foshan cohort, n=158). The primary endpoint was distant metastasis-free survival. Secondary endpoints were disease-free survival and overall survival. FINDINGS: We identified 137 differentially expressed genes between metastatic and non-metastatic locoregionally advanced nasopharyngeal carcinoma tissues. A distant metastasis gene signature for locoregionally advanced nasopharyngeal carcinoma (DMGN) that consisted of 13 genes was generated to classify patients into high-risk and low-risk groups in the training cohort. Patients with high-risk scores in the training cohort had shorter distant metastasis-free survival (hazard ratio [HR] 4·93, 95% CI 2·99-8·16; p<0·0001), disease-free survival (HR 3·51, 2·43-5·07; p<0·0001), and overall survival (HR 3·22, 2·18-4·76; p<0·0001) than patients with low-risk scores. The prognostic accuracy of DMGN was validated in the internal and external cohorts. Furthermore, among patients with low-risk scores in the combined training and internal cohorts, concurrent chemotherapy improved distant metastasis-free survival compared with those patients who did not receive concurrent chemotherapy (HR 0·40, 95% CI 0·19-0·83; p=0·011), whereas patients with high-risk scores did not benefit from concurrent chemotherapy (HR 1·03, 0·71-1·50; p=0·876). This was also validated in the two external cohorts combined. We developed a nomogram based on the DMGN and other variables that predicted an individual's risk of distant metastasis, which was strengthened by adding Epstein-Barr virus DNA status. INTERPRETATION: The DMGN is a reliable prognostic tool for distant metastasis in patients with locoregionally advanced nasopharyngeal carcinoma and might be able to predict which patients benefit from concurrent chemotherapy. It has the potential to guide treatment decisions for patients at different risk of distant metastasis. FUNDING: The National Natural Science Foundation of China, the National Science & Technology Pillar Program during the Twelfth Five-year Plan Period, the Natural Science Foundation of Guang Dong Province, the National Key Research and Development Program of China, the Innovation Team Development Plan of the Ministry of Education, the Health & Medical Collaborative Innovation Project of Guangzhou City, China, and the Program of Introducing Talents of Discipline to Universities.

Prognostic significance of tumor-infiltrating lymphocytes in nondisseminated nasopharyngeal carcinoma: A large-scale cohort study.

The American Joint Committee on Cancer (AJCC) staging system is inadequate for an accurate prognosis in nasopharyngeal carcinoma (NPC). Thus, new biomarkers are under intense investigation. Here, we investigated whether the density of TILs could predict prognosis in NPC. First, we used 1490 cases of nasopharyngeal carcinoma samples from two independent cohorts to evaluate the density and distribution of tumor-infiltrating lymphocytes (TILs). Second, in one cohort, we assessed associations between TILs and clinical outcomes in 593 randomly selected samples (defined as the training set) and validated findings in the remaining 593 samples (defined as the validation set). Furthermore, we confirmed the prognostic value of TILs in a second independent cohort of 304 cases (defined as the independent set). Based on multivariable Cox regression analysis, we also established an effective prognostic nomogram including TILs to improve accuracy in predicting disease-free survival (DFS) for patients with nondisseminated NPC. We found that high TILs in the training set were significantly associated with favorable DFS [hazard ratio (HR) 0.41, 95% confidence interval (CI) 0.28-0.58, p < 0.001], overall survival (OS, HR 0.42, 95% CI 0.27-0.64, p < 0.001), distant metastasis-free survival (DMFS, HR 0.37, 95% CI 0.23-0.58, p < 0.001) and local-regional recurrent free survival (LRRFS, HR 0.43, 95% CI 0.25-0.73, p = 0.002). Multivariate analysis showed that TILs are an independent prognostic indicator for DFS in all cohorts. In summary, this study indicated that TILs may reflect the immunological heterogeneity of NPC and could represent a new prognostic biomarker.

Differential genome-wide profiling of alternative polyadenylation sites in nasopharyngeal carcinoma by high-throughput sequencing.

BACKGROUND: Alternative polyadenylation (APA) is a widespread phenomenon in the posttranscriptional regulation of gene expression that generates mRNAs with alternative 3'-untranslated regions (3'UTRs). APA contributes to the pathogenesis of various diseases, including cancer. However, the potential role of APA in the development of nasopharyngeal carcinoma (NPC) remains largely unknown. METHODS: A strategy of sequencing APA sites (SAPAS) based on second-generation sequencing technology was carried out to explore the global patterns of APA sites and identify genes with tandem 3'UTRs in samples from 6 NPC and 6 normal nasopharyngeal epithelial tissue (NNET). Sequencing results were then validated using quantitative RT-PCR in a larger cohort of 16 NPC and 16 NNET samples. RESULTS: The sequencing data showed that the use of tandem APA sites was prevalent in NPC, and numerous genes with APA-switching events were discovered. In total, we identified 195 genes with significant differences in the tandem 3'UTR length between NPC and NNET; including 119 genes switching to distal poly (A) sites and 76 genes switching to proximal poly (A) sites. Several gene ontology (GO) terms were enriched in the list of genes with switched APA sites, including regulation of cell migration, macromolecule catabolic process, protein catabolic process, proteolysis, small conjugating protein ligase activity, and ubiquitin-protein ligase activity. CONCLUSIONS: APA site-switching events are prevalent in NPC. APA-mediated regulation of gene expression may play an important role in the development of NPC, and more detailed studies targeting genes with APA-switching events may contribute to the development of novel future therapeutic strategies for NPC.

High expression of Talin-1 is associated with poor prognosis in patients with nasopharyngeal carcinoma.

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 < 0.05). Stratified analysis demonstrated that high expression of Talin-1 was associated with significantly poorer survival in patients with advanced stage disease (stage III-IV, HR, 1.91; 95% CI, 1.09-3.35; P = 0.02 for OS and HR, 2.22; 95% CI, 1.24-3.99; P = 0.006 for DMFS). Furthermore, the depletion of Talin-1 suppressed the migratory and invasive ability of NPC cells in vitro. CONCLUSIONS: Our data demonstrate that high expression of Talin-1 is associated with significantly poorer OS and poorer DMFS in NPC and depletion of Talin-1 expression inhibited NPC cell migration and invasion. Talin-1 may serve as novel prognostic biomarker in NPC.

Overexpression of CIP2A is an independent prognostic indicator in nasopharyngeal carcinoma and its depletion suppresses cell proliferation and tumor growth.

BACKGROUND: Cancerous inhibitor of protein phosphatase 2A (CIP2A) is an oncoprotein that acts as a prognostic marker for several human malignancies. In this study, we investigated the clinical significance of CIP2A and its function in nasopharyngeal carcinoma (NPC). METHODS: Quantitative RT-PCR, western blot, and immunohistochemistry analyses were used to quantify CIP2A expression in NPC cell lines and clinical samples. Kaplan-Meier curves were used to estimate the association between CIP2A expression and patient survival. The functional role of CIP2A in NPC cell lines was evaluated by small interfering RNA-mediated depletion of the protein followed by analyses of cell proliferation and xenograft growth. RESULTS: CIP2A levels were upregulated in NPC cell lines and clinical samples at both the mRNA and protein levels (P < 0.01). Patients with high CIP2A expression had poorer overall survival (HR, 1.98; 95% CI, 1.16-3.34; P = 0.01) and poorer disease-free survival (HR, 1.68; 95% CI, 1.07-2.62; P = 0.02) rates than patients with low CIP2A expression. In addition, CIP2A expression status was an independent prognostic indicator for NPC patients. The depletion of CIP2A expression inhibited c-Myc protein expression in NPC cell lines, suppressed cell viability, colony formation, and anchorage-independent growth in vitro, and inhibited xenograft tumor growth in vivo. CONCLUSIONS: Our data demonstrate that high CIP2A expression in patients was associated with poor survival in NPC, and depletion of CIP2A expression inhibited NPC cell proliferation and tumor growth. Thus, these results warrant further investigation of CIP2A as a novel therapeutic target for the treatment of NPC.

A four-miRNA signature identified from genome-wide serum miRNA profiling predicts survival in patients with nasopharyngeal carcinoma.

Recent findings have reported that human serum microRNAs (miRNAs) can be used as prognostic biomarkers in various cancers. We aimed to explore the prognostic value of serum miRNAs in nasopharyngeal carcinoma (NPC) patients. The level of serum miRNA was retrospectively analyzed in 512 NPC patients recruited between January 2001 and December 2006. In the discovery stage, a microarray followed by reverse transcription-quantitative polymerase chain reaction was used to identify differentially altered miRNAs in eight patients with shorter survival and eight patients with longer survival who were well matched by age, sex and clinical stage. The identified serum miRNAs were then validated in all 512 samples, which were randomly divided into a training set and a validation set. Four serum miRNAs (miR-22, miR-572, miR-638 and miR-1234) were found to be differentially altered and were used to construct a miRNA signature. Risk scores were calculated to classify the patients into high- or low-risk groups. Patients with high-risk scores had poorer overall survival [hazard ratio (HR), 2.54; 95% confidence interval (CI), 1.57-4.12; p < 0.001] and distant metastasis-free survival (HR, 3.28; 95% CI, 1.82-5.94; p < 0.001) than those with low-risk scores in the training set; these results were confirmed in the validation and combined sets. The miRNA signature and TNM stage were independent prognostic factors. The combination of the miRNA signature and TNM stage had a better prognostic value than the TNM stage or miRNA signature alone. The four-serum miRNA signature may add prognostic value to the TNM staging system and provide information for personalized therapy in NPC.

PJA1-mediated suppression of pyroptosis as a driver of docetaxel resistance in nasopharyngeal carcinoma.

Chemoresistance is a main reason for treatment failure in patients with nasopharyngeal carcinoma, but the exact regulatory mechanism underlying chemoresistance in nasopharyngeal carcinoma remains to be elucidated. Here, we identify PJA1 as a key E3 ubiquitin ligase involved in nasopharyngeal carcinoma chemoresistance that is highly expressed in nasopharyngeal carcinoma patients with nonresponse to docetaxel-cisplatin-5-fluorouracil induction chemotherapy. We find that PJA1 facilitates docetaxel resistance by inhibiting GSDME-mediated pyroptosis in nasopharyngeal carcinoma cells. Mechanistically, PJA1 promotes the degradation of the mitochondrial protein PGAM5 by increasing its K48-linked ubiquitination at K88, which further facilitates DRP1 phosphorylation at S637 and reduced mitochondrial reactive oxygen species production, resulting in suppression of GSDME-mediated pyroptosis and the antitumour immune response. PGAM5 knockdown fully restores the docetaxel sensitization effect of PJA1 knockdown. Moreover, pharmacological targeting of PJA1 with the small molecule inhibitor RTA402 enhances the docetaxel sensitivity of nasopharyngeal carcinoma in vitro and in vivo. Clinically, high PJA1 expression indicates inferior survival and poor clinical efficacy of TPF IC in nasopharyngeal carcinoma patients. Our study emphasizes the essential role of E3 ligases in regulating chemoresistance and provides therapeutic strategies for nasopharyngeal carcinoma based on targeting the ubiquitin-proteasome system.

Correction: Zhao et al. Hypermethylation of UCHL1 Promotes Metastasis of Nasopharyngeal Carcinoma by Suppressing Degradation of Cortactin (CTTN). Cells 2020, 9, 559.

In the original publication [...].

MiR-451 inhibits cell growth and invasion by targeting MIF and is associated with survival in nasopharyngeal carcinoma.

BACKGROUND: MiRNAs play important roles in diverse biological processes including tumorigenesis. However, little is known about the function and mechanism of miR-451 in nasopharyngeal carcinoma (NPC). METHODS: Quantitative RT-PCR was used to quantify miR-451 expression in NPC cell lines and clinical tissues. Kaplan-Meier curves were used to estimate the association between miR-451 expression and survival. The MTT, colony formation, Transwell migration and invasion assays, and a xenograft model were performed. A miR-451 target was confirmed using luciferase reporter assays, quantitative RT-PCR, and Western blotting. RESULTS: MiR-451 was significantly downregulated in NPC cell lines and clinical tissues (P < 0.01). Patients with low expression of miR-451 had poorer overall survival (HR, 1.98; 95% CI, 1.16-3.34; P = 0.01) and disease-free survival (HR, 1.68; 95% CI, 1.07-2.62; P = 0.02) than patients with high expression. MiR-451 was an independent prognostic factor in NPC in multivariate Cox regression analysis. Ectopic expression of miR-451 suppressed cell viability, colony formation, and cell migration and invasion in vitro, and inhibited xenograft tumor growth in vivo. MIF was verified as a direct target of miR-451, and MIF regulated NPC cell growth and invasion. CONCLUSIONS: The newly identified miR-451/MIF pathway provides insight into NPC initiation and progression, and may represent a novel therapeutic target.

Prognostic value of a microRNA signature in nasopharyngeal carcinoma: a microRNA expression analysis.

BACKGROUND: MicroRNAs (miRNAs) can be used as prognostic biomarkers in many types of cancer. We aimed to identify miRNAs that were prognostic in patients with nasopharyngeal carcinoma. METHODS: We retrospectively analysed miRNA expression profiles in 312 paraffin-embedded specimens of nasopharyngeal carcinoma from Sun Yat-sen University Cancer Center (Guangzhou, China) and 18 specimens of non-cancer nasopharyngitis. Using an 873 probe microarray, we assessed associations between miRNA signatures and clinical outcome in a randomly selected 156 samples (training set) and validated findings in the remaining 156 samples (internal validation set). We confirmed the miRNAs signature using quantitative RT-PCR analysis in 156 samples from a second randomisation of the 312 samples, and validated the miRNA signature in 153 samples from the West China Hospital of Sichuan University in Chengdu, China (independent set). We used the Kaplan-Meier method and log-rank tests to estimate correlations of the miRNA signature with disease-free survival (DFS), distant metastasis-free survival (DMFS), and overall survival. FINDINGS: 41 miRNAs were differentially expressed between nasopharyngeal carcinoma and non-cancer nasopharyngitis tissues. A signature of five miRNAs, each significantly associated with DFS, was identified in the training set. We calculated a risk score from the signature and classified patients as high risk or low risk. Compared with patients with low-risk scores, patients with high risk scores in the training set had shorter DFS (hazard ratio [HR] 2·73, 95% CI 1·46-5·11; p=0·0019), DMFS (3·48, 1·57-7·75; p=0·0020), and overall survival (2·48, 1·24-4·96; p=0·010). We noted equivalent findings in the internal validation set for DFS (2·47, 1·32-4·61; p=0·0052), DMFS (2·28, 1·09-4·80; p=0·030), and overall survival (2·87, 1·38-5·96; p=0·0051) and in the independent set for DFS (3·16, 1·65-6·04; p=0·0011), DMFS (2·39, 1·05-5·42; p=0·037), and overall survival (3·07, 1·34-7·01; p=0·0082). The five-miRNA signature was an independent prognostic factor. A combination of this signature and TNM stage had better prognostic value than did TNM stage alone in the training set (area under receiver operating characteristics 0·68 [95% CI 0·60-0·76] vs 0·60 [0·52-0·67]; p=0·013), the internal validation set (0·70 [0·61-0·78] vs 0·61 [0·54-0·68]; p=0·012), and the independent set (0·70 [0·62-0·78] vs 0·63 [0·56-0·69]; p=0·032). INTERPRETATION: Identification of patients with the five-miRNA signature might add prognostic value to the TNM staging system and inform treatment decisions for patients at high risk of progression. FUNDING: Science Foundation of Chinese Ministry of Health, National Natural Science Foundation of China, Pearl River Scholar Funded Scheme, Guangdong Key Scientific and Technological Innovation Program, Guangdong Natural Science Foundation, Fundamental Research Funds for the Central Universities.

Integrated proteomics and phosphoproteomics analyses of esophageal cancer cells with different invasive abilities.

AIMS: Esophageal squamous cell carcinoma (ESCC) is one of the aggressive and lethal malignancies with an extremely poor prognosis. It is necessary to explore the molecular mechanisms of ESCC invasion. MAIN METHODS: We utilized high-throughput mass spectrometry to analyze the proteomes and phosphorylation profiles of two ESCC cell lines with differing invasion capacities (HK vs TE10). Differentially expressed proteins and phosphorites were identified, followed by comprehensive bioinformatics analyses encompassing function and pathway enrichment, protein-protein interaction (PPI) network analysis, hub gene identification, co-expression analysis, kinase-substrate prediction, and drug-target network analysis. CCK-8 assay, transwell examination, wound-healing assay, and western blot was used to validate the effects of fostamatinib on ESCC cells proliferation, invasion, migration, and LYN expression. KEY FINDINGS: The Q4 cluster of differentially phosphorylated proteins was primarily associated with functions and pathways relevant to tumor metastasis. Phosphorylated hub proteins including ARHGAP35, CTNNA1, and SHC1 were identified through the analysis of PPI network, and their respective regulated kinases were predicted. Among the predicted kinases, LYN was validated to be associated with lymph node metastasis (N0 vs. N1-3) and prognosis in ESCC patients at mRNA levels using TGGA data and protein levels in ESCC tissues (p < 0.05). Validation experiments confirmed the inhibitory effects of fostamatinib on ESCC cells proliferation, migration, invasion, and LYN expression. SIGNIFICANCE: Our multi-omics analysis offers deeper perspectives on ESCC invasiveness and unveils new phosphorylated hub proteins with their regulatory kinase. This study also suggests that fostamatinib may be a potential agent for treating ESCC.

Chemotherapy-Induced Senescence Reprogramming Promotes Nasopharyngeal Carcinoma Metastasis by circRNA-Mediated PKR Activation.

Senescence is associated with tumor metastasis and chemotherapy resistance, yet the mechanisms remain elusive. Here, it is identified that nasopharyngeal carcinoma (NPC) patients who developed distant metastasis are characterized by senescence phenotypes, in which circWDR37 is a key regulator. CircWDR37 deficiency limits cisplatin or gemcitabine-induced senescent NPC cells from proliferation, migration, and invasion. Mechanistically, circWDR37 binds to and dimerizes double-stranded RNA-activated protein kinase R (PKR) to initiate PKR autophosphorylation and activation. Independent of its kinase activity, phosphorylated PKR induces I-kappaB kinase beta (IKKß) phosphorylation, binds to and releases RELA from NF-κB inhibitor alpha (IκBα) to trigger nuclear factor kappa B (NF-κB) activation, thereby stimulating cyclin D1 (CCND1) and senescence-associated secretory phenotype component gene transcription in a circWDR37-dependent manner. Low circWDR37 levels correlate with chemotherapy response and favorable survival in NPC patients treated with gemcitabine or cisplatin induction chemotherapy. This study uncovers a new mechanism of circWDR37 activated PKR in senescence-driven metastasis and provides appealing therapeutic targets in NPC.

Erratum: Long non-coding RNA DANCR stabilizes HIF-1α and promotes metastasis by interacting with NF90/NF45 complex in nasopharyngeal carcinoma: Erratum.

[This corrects the article DOI: 10.7150/thno.28538.].

A tumor microenvironment-associated circRNA predictor for tumor relapse and chemotherapy vulnerability in nasopharyngeal carcinoma.

Accurate risk stratification for patients with locoregionally advanced nasopharyngeal carcinoma (LA-NPC) is crucial for prognosis and treatment decisions. Here, we develop a tumor microenvironment-associated circular RNA (circRNA) signature that can stratify LA-NPC patients with different risks of relapse and vulnerability to induction chemotherapy (IC). Relapsed-related circRNAs are identified by comparing expression profiles between patients with and without relapse, followed by quantitative validation in the training cohort (n = 170). A nine-circRNA signature is constructed to classify patients into high-risk and low-risk groups. Low-risk patients have significantly favorable clinical survivals, which is validated in the internal (n = 170) and external (n = 150) cohorts. They are characterized by an immune-active microenvironment and can derive benefits from IC. Meanwhile, high-risk patients characterized with pro-relapse and DNA repair-associated features, are vulnerable to chemoresistance. Overall, the circRNA-based classifier serves as a reliable prognostic tool and might guide chemotherapy decisions for patients with LA-NPC.

TRIM21 inhibits irradiation-induced mitochondrial DNA release and impairs antitumour immunity in nasopharyngeal carcinoma tumour models.

Although radiotherapy can promote antitumour immunity, the mechanisms underlying this phenomenon remain unclear. Here, we demonstrate that the expression of the E3 ubiquitin ligase, tumour cell-intrinsic tripartite motif-containing 21 (TRIM21) in tumours, is inversely associated with the response to radiation and CD8+ T cell-mediated antitumour immunity in nasopharyngeal carcinoma (NPC). Knockout of TRIM21 modulates the cGAS/STING cytosolic DNA sensing pathway, potentiates the antigen-presenting capacity of NPC cells, and activates cytotoxic T cell-mediated antitumour immunity in response to radiation. Mechanistically, TRIM21 promotes the degradation of the mitochondrial voltage-dependent anion-selective channel protein 2 (VDAC2) via K48-linked ubiquitination, which inhibits pore formation by VDAC2 oligomers for mitochondrial DNA (mtDNA) release, thereby inhibiting type-I interferon responses following radiation exposure. In patients with NPC, high TRIM21 expression was associated with poor prognosis and early tumour relapse after radiotherapy. Our findings reveal a critical role of TRIM21 in radiation-induced antitumour immunity, providing potential targets for improving the efficacy of radiotherapy in patients with NPC.

The tumor immune microenvironment of nasopharyngeal carcinoma after gemcitabine plus cisplatin treatment.

Gemcitabine plus cisplatin (GP) chemotherapy is the standard of care for nasopharyngeal carcinoma (NPC). However, the mechanisms underpinning its clinical activity are unclear. Here, using single-cell RNA sequencing and T cell and B cell receptor sequencing of matched, treatment-naive and post-GP chemotherapy NPC samples (n = 15 pairs), we show that GP chemotherapy activated an innate-like B cell (ILB)-dominant antitumor immune response. DNA fragments induced by chemotherapy activated the STING type-I-interferon-dependent pathway to increase major histocompatibility complex class I expression in cancer cells, and simultaneously induced ILB via Toll-like receptor 9 signaling. ILB further expanded follicular helper and helper type 1 T cells via the ICOSL-ICOS axis and subsequently enhanced cytotoxic T cells in tertiary lymphoid organ-like structures after chemotherapy that were deficient for germinal centers. ILB frequency was positively associated with overall and disease-free survival in a phase 3 trial of patients with NPC receiving GP chemotherapy ( NCT01872962 , n = 139). It also served as a predictor for favorable outcomes in patients with NPC treated with GP and immunotherapy combined treatment (n = 380). Collectively, our study provides a high-resolution map of the tumor immune microenvironment after GP chemotherapy and uncovers a role for B cell-centered antitumor immunity. We also identify and validate ILB as a potential biomarker for GP-based treatment in NPC, which could improve patient management.

Nuclear overexpression of metastasis-associated protein 1 correlates significantly with poor survival in nasopharyngeal carcinoma.

BACKGROUND: Metastasis-associated protein 1 (MTA1) has been associated with poor prognosis in several malignant carcinomas. The purpose of this study was to investigate the expression and prognostic value of MTA1 in nasopharyngeal carcinoma (NPC). METHODS: MTA1 expression was assessed using immunohistochemistry in paraffin-embedded tumor specimens from 208 untreated NPC patients. Cox regression analysis was used to calculate the hazard ratio (HR), 95% confidence interval (CI) and identify independent prognostic factors, and recursive partitioning analysis was used to create a decision tree. RESULTS: Nuclear overexpression of MTA1 was observed in 48.6% (101/208) of the NPC tissues. Nuclear overexpression of MTA1 correlated positively with N classification (P = 0.02), clinical stage (P = 0.04), distant metastasis (P < 0.01) and death (P = 0.01). Additionally, nuclear overexpression of MTA1 correlated significantly with poorer distant metastasis-free survival (DMFS; P <0.01) and poorer overall survival (OS; P < 0.01). MTA1 had prognostic significance in NPC patients with stage II disease, but not stage III or IV disease. Multivariate analysis demonstrated that nuclear overexpression of MTA1 was independently associated with poorer DMFS (HR, 2.05; 95% CI, 1.13-3.72; P = 0.02) and poorer OS (HR, 1.98; 95% CI, 1.09-3.59; P = 0.03). Using recursive partitioning analysis, the NPC patients could be classified with a low, intermediate or high risk of distant metastasis and death, on the basis of clinical stage, age and MTA1 expression. CONCLUSION: The results of this study suggest that nuclear overexpression of MTA1 correlates significantly with poorer DMFS and poorer OS in NPC. MTA1 has potential as a novel prognostic biomarker in NPC.