Characterization of PD-L1 and PD-1 Expression and CD8+ Tumor-infiltrating Lymphocyte in Epstein-Barr Virus-associated Nasopharyngeal Carcinoma

A nomogram based on circulating CD8+ T cell and platelet-to-lymphocyte ratio to predict overall survival of patients with locally advanced nasopharyngeal carcinoma

PURPOSE

To explore the influence of circulating lymphocyte subsets, serum markers, clinical factors, and their impact on overall survival (OS) in locally advanced nasopharyngeal carcinoma (LA-NPC). Additionally, to construct a nomogram predicting OS for LA-NPC patients using independent prognostic factors.

METHODS

A total of 530 patients with LA-NPC were included in this study. In the training cohort, Cox regression analysis was utilized to identify independent prognostic factors, which were then integrated into the nomogram. The concordance index (C-index) was calculated for both training and validation cohorts. Schoenfeld residual analysis, calibration curves, and decision curve analysis (DCA) were employed to evaluate the nomogram. Kaplan-Meier methods was performed based on risk stratification using the nomogram.

RESULTS

A total of 530 LA-NPC patients were included. Multivariate Cox regression analysis revealed that the circulating CD8+T cell, platelet-to-lymphocyte ratio (PLR), lactate dehydrogenase (LDH), albumin (ALB), gender, and clinical stage were independent prognostic factors for LA-NPC (p < 0.05). Schoenfeld residual analysis indicated overall satisfaction of the proportional hazards assumption for the Cox regression model. The C-index of the nomogram was 0.724 (95% CI: 0.669-0.779) for the training cohort and 0.718 (95% CI: 0.636-0.800) for the validation cohort. Calibration curves demonstrated good correlation between the model and actual survival outcomes. DCA confirmed the clinical utility enhancement of the nomogram over the TNM staging system. Significant differences were observed in OS among different risk stratifications.

CONCLUSION

Circulating CD8+ T cell, PLR, LDH, ALB, gender and clinical stage are independent prognostic factors for LA-NPC. The nomogram and risk stratification constructed in this study effectively predict OS in LA-NPC.

Combination strategy exploration for prior treated recurrent or metastatic nasopharyngeal carcinoma in the era of immunotherapy

To assess the efficacy and safety of the combination of immune checkpoint inhibitors (ICIs) and target therapy (anti-angiogenesis or EGFR inhibitors) as a second-line or subsequent treatment for recurrent or metastatic nasopharyngeal carcinoma (R/M NPC), we conducted a retrospective study. In this study, previously treated R/M NPC patients were administered one of the following treatment: ICIs combined with target therapy and chemotherapy (ITC), ICIs combined with target therapy alone (IT), ICIs combined with chemotherapy (IC), or chemotherapy alone (C). The primary endpoint under consideration was progression-free survival (PFS), while secondary endpoints included overall survival (OS), objective response rate (ORR), disease control rate (DCR), and safety measures. A total of 226 patients participated in this study, with 70 receiving the ITC regimen, 48 receiving IT, 48 treated with IC, and 60 undergoing C alone. The median PFS for the four cohorts was 20.67, 13.63, 12.47, and 7.93 months respectively. Notably, ITC regimen yielded the most favorable PFS among these cohorts. The ITC cohort exhibited a comparable tumor response and safety profile to the IT and IC cohorts (p > 0.05), but superior tumor response compared to the C cohort (p < 0.05). The ITC regimen also conferred a significant improvement in OS when comparing to C alone (HR 0.336, 95%CI 0.123-0.915, p = 0.033). The IT and IC regimens achieved a nearly identical PFS (HR 0.955, 95%CI 0.515-1.77, p = 0.884), although the IT regimen was associated with a lower occurrence of SAEs in contrast to the IC regimen (p < 0.05). In addition, the IT regimen demonstrated superior PFS (HR 0.583, 95%CI 0.345-0.985, p = 0.044) and fewer SAEs when compared to C alone (p < 0.05). These findings collectively support the notion that the combination of ICIs, target and chemotherapy exhibits robust antitumor activity in previously treated R/M NPC patients, without a significant increase in adverse events.

Preliminary evidence for endoscopic surgery combined with postoperative anti-PD-1 immunotherapy in advanced recurrent nasopharyngeal carcinoma

BACKGROUD

Endoscopic surgery can be used as the main treatment for advanced recurrent nasopharyngeal carcinoma (rNPC). However, there is a huge clinical controversy about the need for consolidated immunotherapy after surgery.

METHODS

We performed a retrospective propensity score-matched analysis (1:2) of patients with locally advanced rNPC who underwent endoscopic nasopharyngectomy (ENPG) combined with anti-programmed cell death protein-1 (PD-1) monotherapy or ENPG alone. The survival rate was analyzed by Kaplan-Meier method. The primary endpoint was progression-free survival (PFS). The secondary endpoints included overall survival (OS), objective response rate (ORR) and disease control rate (DCR). Potential surgical-related complications and immune-related adverse events (AEs) were also assessed.

RESULTS

We recruited 10 patients receiving ENPG plus anti-PD-1 monotherapy and 20 receiving ENPG alone. During the mean follow-up of 23.8 months, a significant improvement in the 2-year PFS was detected in the consolidation immunotherapy group compared to the ENPG alone group (80.0% vs. 40.0%; HR = 0.258; 95% CI: 0.09-0.72; p = 0.04), while the 2-year OS in the consolidation immunotherapy group was not significantly longer than that in the ENPG alone group (90.0% vs. 75.0%; HR = 0.482; 95% CI: 0.08-3.00; p = 0.50). The incidence of surgical-related complications in the consolidation immunotherapy group and ENPG alone group was 70.0 and 60.0%, respectively. Immune-related AEs were similar between the toripalimab arm (75.0%) and the camrelizumab arm (66.7%). Surgical-related complications depend on symptomatic treatments. Immune-related AEs were mild and tolerable.

CONCLUSIONS

Consolidation immunotherapy regimen for patients with advanced rNPC after ENPG compared to ENPG alone provides a superior PFS rate with a manageable safety profile.

Recent Advances in Assessing the Clinical Implications of Epstein-Barr Virus Infection and Their Application to the Diagnosis and Treatment of Nasopharyngeal Carcinoma

Reports about the oncogenic mechanisms underlying nasopharyngeal carcinoma (NPC) have been accumulating since the discovery of Epstein-Barr virus (EBV) in NPC cells. EBV is the primary causative agent of NPC. EBV-host and tumor-immune system interactions underlie the unique representative pathology of NPC, which is an undifferentiated cancer cell with extensive lymphocyte infiltration. Recent advances in the understanding of immune evasion and checkpoints have changed the treatment of NPC in clinical settings. The main EBV genes involved in NPC are LMP1, which is the primary EBV oncogene, and BZLF1, which induces the lytic phase of EBV. These two multifunctional genes affect host cell behavior, including the tumor-immune microenvironment and EBV behavior. Latent infections, elevated concentrations of the anti-EBV antibody and plasma EBV DNA have been used as biomarkers of EBV-associated NPC. The massive infiltration of lymphocytes in the stroma suggests the immunogenic characteristics of NPC as a virus-infected tumor and, at the same time, also indicates the presence of a sophisticated immunosuppressive system within NPC tumors. In fact, immune checkpoint inhibitors have shown promise in improving the prognosis of NPC patients with recurrent and metastatic disease. However, patients with advanced NPC still require invasive treatments. Therefore, there is a pressing need to develop an effective screening system for early-stage detection of NPC in patients. Various modalities, such as nasopharyngeal cytology, cell-free DNA methylation, and deep learning-assisted nasopharyngeal endoscopy for screening and diagnosis, have been introduced. Each modality has its advantages and disadvantages. A reciprocal combination of these modalities will improve screening and early diagnosis of NPC.

Case report: Leptomeningeal metastasis of advanced nasopharyngeal carcinoma treated with chemoimmunotherapy

Leptomeningeal metastasis (LM) of nasopharyngeal carcinoma (NPC) is rare and associated with a poor prognosis. Immune checkpoint inhibitors (ICIs) have been the standard first-line treatment for metastatic NPC, but their effect on meningeal metastasis of NPC needs further investigation. A 38-year-old man complained of bilateral neck masses and sought medical care. He was diagnosed with nasopharyngeal undifferentiated non-keratinizing carcinoma with bilateral cervical lymph node metastasis and multiple bone metastasis, stage cT4N2M1 IVb. Then, the patient received first-line anti-PD-1 antibody tislelizumab combined with gemcitabine and cisplatin and achieved partial response. After seven cycles of first-line chemoimmunotherapy, the patient subsequently developed neurological symptoms, including unsteady walking, slurred speech, coughing on drinking, and unconsciousness. MRI showed leptomeningeal linear enhancement, and cerebrospinal fluid (CSF) analysis indicated Epstein-Barr virus (EBV) infection and squamous cell carcinoma cytology, suggesting the diagnosis of leptomeningeal metastasis. After the definite diagnosis of LM, the patient's condition deteriorated rapidly, leading to his death from brain herniation. We reported the first case of advanced NPC with pathologically confirmed leptomeningeal metastasis after receiving first-line chemoimmunotherapy. Considering the poor prognosis of LM, it is suggested to perform MRI and CSF examination when patients have neurological symptoms. Although immunotherapy significantly improved survival outcomes of advanced NPC patients, it seemed not effective in the setting of LM. The effect of other treatment options, such as radiation therapy and intrathecal therapy, requires further verification.

Combinations of radiotherapy with immunotherapy in nasopharyngeal carcinoma

BACKGROUND

The treatment of nasopharyngeal carcinoma (NPC) is currently based on concurrent chemoradiotherapy. The prognosis of early NPC is better, while the prognosis of advanced NPC is poor. Immunotherapy is becoming increasingly commonly employed in clinical practice as a new strategy for treating malignant tumors. It has shown promising results in the treatment of certain malignant tumors, making it a current clinical research hotspot.

METHODS

This review summarizes the current immunotherapy on NPC, highlighting the application of immunotherapy and radiotherapy in the treatment of NPC.

RESULTS

X-rays can either increase or suppress anti-tumor immune responses through various pathways and mechanisms. Immune checkpoint inhibitors can usually enhance X-ray-induced anti-tumor immune responses. Detecting the immune checkpoint markers and tumor mutation markers, and the functional status of effector cells in patients can aid in the development of individualized treatment that improves the treatment efficacy with reducing drug resistance and adverse reactions. The development of a multivalent vaccine for NPC will help improve the efficacy of the vaccine. Combining techniques that increase the tumor antigens release, such as radiotherapy and oncolytic virus vaccines, may enhance the ability of the immune response.

CONCLUSIONS

To shed further light on the application of immunotherapy in NPC, large pooled studies must accumulate sufficient cases with detailed exposure data.

Anti-PD-1/PD-L1 for nasopharyngeal carcinoma: a comprehensive analysis of registered trials on ClinicalTrials.gov

Objective: Clinical trials play an important role in the development of healthcare. However, the current status of clinical trials on anti-PD-1/PD-L1 for nasopharyngeal carcinoma remains unclear. Therefore, this study aims to provide a comprehensive analysis of the registered trials related to anti-PD-1/PD-L1 for nasopharyngeal carcinoma on ClinicalTrials.gov. Methods: A search was conducted on the ClinicalTrials.gov database to identify all registered trials related to anti-PD-1/PD-L1 for nasopharyngeal carcinoma up to 26 February 2023. The characteristics of the trials were examined, and the studied drugs, disease conditions, as well as details of trials with available results were analyzed. Publication status was assessed by a PubMed search using the ClinicalTrials.gov NCT number. Results: A total of 112 interventional clinical trials registered between 2015 and 2023 were included. Of the trials, 90 were carried out in Asia, 72 were in phase 2, and 31 trials had either companies or universities as sponsors/collaborators. The sample sizes across the trials varied greatly, with a median of 71.5 participants per trial. The majority of trials were recruiting participants, with only 6 had posted results. PD-1 inhibitors were preferred over PD-L1, and Toripalimab emerged as the most extensively studied drug. About one-third (33.9%) of the studies looked into recurrent/metastatic nasopharyngeal cancer. Conclusion: This study provides an overview of all registered trials of anti-PD-1/PD-L1 for NPC. It is needed to improve the completeness, outcome selection, randomization and masking of trials and to be transparent and timely in reporting of results.

Anti-PD1 rechallenge in combination with anti-angiogenesis or anti-EGFR treatment beyond progression in recurrent/metastatic nasopharyngeal carcinoma patients

We aim to evaluate the efficacy and safety of anti-PD1 rechallenge in combination with anti-angiogenesis or anti-EGFR treatment in recurrent/metastatic nasopharyngeal carcinoma (R/M NPC) patients who progressed to previous anti-PD1 therapy. Enrolled patients were divided into a combination group and a chemotherapy only group. A total of 145 patients were enrolled. The median progress-free survival (mPFS) was 7.9 months and 4.4 months, respectively for the two groups. The combination group exhibited significantly longer PFS (HR=0.363, p < 0.001), and better disease control ratio (DCR, p = 0.022) compared with the chemotherapy group. Among the combination group, longer PFS was found in those patients who received different PD1 inhibitor from prior therapy, reached object response rate (ORR) from prior anti-PD1 therapy, and EBV DNA ≤ 1500 copy/ml before therapy, comparing to the corresponding other patients. R/M NPC patients who progressed from prior anti-PD1 therapy could benefit from the anti-PD1 rechallenge in combination with anti-angiogenesis or anti-EGFR agents.

Impact of Epstein Barr Virus Infection on Treatment Opportunities in Patients with Nasopharyngeal Cancer

Chemical, physical, and infectious agents may induce carcinogenesis, and in the latter case, viruses are involved in most cases. The occurrence of virus-induced carcinogenesis is a complex process caused by an interaction across multiple genes, mainly depending by the type of the virus. Molecular mechanisms at the basis of viral carcinogenesis, mainly suggest the involvement of a dysregulation of the cell cycle. Among the virus-inducing carcinogenesis, Epstein Barr Virus (EBV) plays a major role in the development of both hematological and oncological malignancies and importantly, several lines of evidence demonstrated that nasopharyngeal carcinoma (NPC) is consistently associated with EBV infection. Cancerogenesis in NPC may be induced by the activation of different EBV "oncoproteins" which are produced during the so called "latency phase" of EBV in the host cells. Moreover, EBV presence in NPC does affect the tumor microenvironment (TME) leading to a strongly immunosuppressed status. Translational implications of the above-mentioned statements are that EBV-infected NPC cells can express proteins potentially recognized by immune cells in order to elicit a host immune response (tumor associated antigens). Three immunotherapeutic approaches have been implemented for the treatment of NPC including active, adoptive immunotherapy, and modulation of immune regulatory molecules by use of the so-called checkpoint inhibitors. In this review, we will highlight the role of EBV infection in NPC development and analyze its possible implications on therapy strategies.

CD8+ Tumor-Infiltrating Lymphocyte Abundance Is a Positive Prognostic Indicator in Nasopharyngeal Cancer

PURPOSE

Tumor-infiltrating lymphocytes (TIL) are immune cell populations found within tumors, critical in the antigen-specific host immune response. In this study, we aimed to elucidate the prognostic significance of CD3+, CD4+, and CD8+ TILs in nasopharyngeal cancer (NPC).

EXPERIMENTAL DESIGN

Immune cell infiltration was quantified in NPC samples (n = 50) using RNA-sequencing (RNA-seq) data based on rearranged T-cell receptor (TCR) reads and the Estimation of Stromal and Immune cells in malignant tumors using expression data (ESTIMATE) immune score tool. The differential abundances of TIL subset populations were also characterized through IHC staining of formalin-fixed, paraffin-embedded samples from a training cohort (n = 35), which was a subset of the RNA-seq cohort (n = 50).

RESULTS

In the RNA-seq cohort, patients with higher rearranged TCR reads experienced superior 5- and 10-year overall survival (OS; P < 0.001), and disease-free survival (DFS; P < 0.001). Similarly, patients with higher ESTIMATE immune scores experienced superior 5- and 10-year OS (P = 0.024) and DFS (P = 0.007). In the training cohort, high abundances of CD8+ TILs were significantly associated with improved 5- and 10-year OS (P = 0.003) and DFS (P = 0.005). These findings were corroborated in an independent validation cohort (n = 84), and combined analysis of the training and validation cohorts [n = 119 (35+84)], which further demonstrated improved 5- and 10-year survival in terms of locoregional control (P < 0.001) and distant metastasis (P = 0.03).

CONCLUSIONS

Taken together, our study highlights the prognostic value of CD8+ TILs in NPC, and the potential of future investigations into cellular-based immunotherapies employing CD8+ lymphocytes.

Spatial architecture of regulatory T-cells correlates with disease progression in patients with nasopharyngeal cancer

Purpose

This study aims to investigate the prognostic value of composition and spatial architecture of tumor-infiltrating lymphocytes (TILs) as well as PDL1 expression on TILs subpopulations in nasopharyngeal carcinoma (NPC).

Methods

A total of 121 patients with NPC were included and divided into two groups: favorable (n = 68) and unfavorable (n = 53). The archived tumor tissues of the included patients were retrieved, and a tissue microarray was constructed. The density and spatial distribution of TILs infiltration were analyzed using the multiplex fluorescent immunohistochemistry staining for CD3, CD4, CD8, Foxp3, cytokeratin (CK), PDL1, and 4′,6-diamidino-2-phenylindole (DAPI). The infiltration density of TILs subpopulations and PDL1 expression were compared between the two groups. The Gcross function was calculated to quantify the relative proximity of any two types of cells. The Cox proportional hazards regression model was used to identify factors associated with overall survival (OS) and disease-free survival (DFS).

Results

The densities of regulatory T-cells (Tregs), effector T-cells (Teffs), PDL1+ Tregs, and PDL1+ Teffs were significantly higher in patients with unfavorable outcomes. PDL1 expression on tumor cells (TCs) or overall TILs was not associated with survival. Multivariate analysis revealed that higher PDL1+ Tregs infiltration density was independently associated with inferior OS and DFS, whereas Tregs infiltration density was only a prognostic marker for DFS. Spatial analysis revealed that unfavorable group had significantly stronger Tregs and PDL1+ Tregs engagement in the proximity of TCs and cytotoxic T lymphocyte (CTLs). Gcross analysis further revealed that Tregs and PDL1+ Tregs were more likely to colocalize with CTLs. Moreover, increased G_TC : _Treg (Tregs engagement surrounding TCs) and G_CTL : _{PDL1+ Treg} were identified as independent factors correlated with poor outcomes.

Conclusion

TILs have a diverse infiltrating pattern and spatial distribution in NPC. Increased infiltration of Tregs, particularly PDL1+ Tregs, as well as their proximity to TCs and CTLs, correlates with unfavorable outcomes, implying the significance of intercellular immune regulation in mediating disease progression.

Current status and advances of immunotherapy in nasopharyngeal carcinoma

The general immune landscape of nasopharyngeal carcinoma (NPC) renders immunotherapy suitable for patients with NPC. Immune checkpoint inhibitors (ICIs) based on programmed death-1/programmed death ligand-1 (PD-1/PD-L1) blockade have made a breakthrough with the approval of PD-1 inhibitor for refractory recurrence and/or metastatic (R/M NPC) and the approval of PD-1 inhibitor in combination with gemcitabine and cisplatin as first line for R/M NPC in 2021 in China. The incorporation of ICIs into the treatment paradigms of NPC has become a clinical hot spot and many prospective clinical studies are ongoing. In this review, we provide a comprehensive overview of the rationale for immunotherapy in NPC and current status, advances and challenges of immunotherapy in NPC based on published clinical data, and ongoing trials. We focus on the clinical application and advances of PD-1 inhibitor monotherapy and its combination with chemotherapy and summarize the clinical explorations of other immunotherapy approaches, for example, combination of PD-1/PD-L1 inhibitors with antiangiogenic inhibitor with molecular targeted agents, cancer vaccines, adaptive immunotherapy, and new ICI agents beyond PD-1/PD-L1 inhibitors in R/M NPC. We also describe the clinical studies’ status and challenges of ICIs-based immunomodulatory strategies in local advanced NPC and pay attention to the biomarker application for personalized immunotherapy of NPC in the hope to provide insights for clinical practice and future clinical studies.

PD-L1 expression in EBV associated gastric cancer: a systematic review and meta-analysis

OBJECTIVES

The aim of this systematic review and meta-analysis is to the summarize the evidence on programmed cell death protein ligand 1 (PD-L1) in Epstein-Barr virus associated gastric cancer (EBVaGC) and to estimate the expression rate of PD-L1 among this subtype of Gastric Cancer (GC).

MATERIALS AND METHODS

For this study, PubMed^®, EMBASE^® and Web of Science^® databases were searched for articles published until 1st November 2021. A total of 43 eligible publications with a total of 11,327 patients were included analysis based on inclusion and exclusion criteria. A total of 41 publications present data for proportion estimation and 33 for comparison of PD-L1 between EBV positive and negative GC. DerSimonian-Laird random-effects model was used for meta-analysis.

RESULTS

The analysis showed that in EBVaGC the pooled positivity rate for PD-L1 was 54.6% (p < 0.001), with a high heterogeneity between the included studies, which was associated with variation on positivity criteria for PD-L1 expression. Overall, the study reveals an increased association between PD-L1 and EBVaGC (OR = 6.36, 95% CI 3.91-10.3, p < 0.001). Furthermore, the study revealed that GC with lymphoid stroma (GCLS) is highly associated with EBV (OR = 17.4, 95% CI 6.83-44.1, p < 0.001), with a pooled EBV positivity rate of 52.9% (p < 0.001).

CONCLUSIONS

Patients with EBVaGC tend to show higher PD-L1 expression, which enhances EBV positivity as a promising marker for patient selection for immunotherapy targeted agents. A uniform criteria for PD-L1 positivity in tumor cells is needed, as well as further prospective studies to validate our findings and their prognostic significance.

[Immunotherapy of head and neck cancer : Highlights of the ASCO and ESMO annual meetings 2021]

BACKGROUND

This year's American Society of Clinical Oncology (ASCO) meeting included interesting data on first-line therapy of nasopharyngeal carcinomas with PD‑1 inhibitors and on checkpoint inhibition in various clinical constellations. At the European Society of Medical Oncology (ESMO) meeting, the results of the CheckMate-651 study were presented.

MATERIALS AND METHODS

All abstracts and presentations from the ASCO and ESMO meetings 2021 on immunotherapy in head and neck cancer (HNSCC) were evaluated for their relevance. The most interesting studies are elaborated upon herein.

RESULTS

Studies on locally advanced HNSCC showed an improved response after neoadjuvant pembrolizumab administration. A second cycle did not improve the response rate, but the proportion of patients with a good response was almost doubled. The CheckRad CD8 study showed an improvement in progression-free survival by induction chemoimmunotherapy with tremelimumab and durvalumab followed by stratification according to the CD8 immune cell infiltrate. Two studies were presented on first-line treatment of recurrent/metastatic nasopharyngeal carcinomas. Chemoimmunotherapy showed a higher response rate and prolonged progression-free survival with a similar adverse event profile. In recurrent/metastatic HNSCC, the CheckMate 651 study showed an increased duration of response with nivolumab and ipilimumab and higher response rates than pembrolizumab alone. The primary endpoints for overall survival were not achieved.

CONCLUSION

PD‑1 inhibition has great potential to change the therapeutic landscape for nasopharyngeal carcinomas in the future. In HNSCC, CD8 tumor infiltrate presents a promising predictive marker for selecting patients who can benefit from radioimmunotherapy. The combination of nivolumab and ipilimumab did not improve overall survival in palliative first-line therapy; thus, no change in the current standard is expected.

Expression of PD‑L1 and CD4+ tumor‑infiltrating lymphocytes predict survival in head and neck squamous cell carcinoma

The clinical efficacy of immune checkpoint blockade has been recently demonstrated in a variety of cancer types. The aim of the present study was to characterize the expression profile of tumor-infiltrating lymphocytes (TILs) and programmed death-ligand 1 (PD-L1) in head and neck squamous carcinoma (HNSCC). A total of 63 patients with HNSCC were enrolled in the present study. CD3⁺ and CD4⁺ TILs and the expression of PD-L1 were detected by immunohistochemistry. PD-L1 mRNA levels were evaluated by reverse transcription-quantitative PCR analysis. The association of TILs and PD-L1 with patient clinicopathological characteristics was also assessed. CD3⁺ and CD4⁺ TILs were detected in 100% of the samples. CD3⁺ was the predominant subset of TILs. PD-L1 was expressed in 53 of 61 (86%) patients when a score of ≥1 on tumor cells was considered positive and in 28 patients (45.2%) when a score of >5 on tumor cells was considered positive. PD-L1 mRNA levels were determined to be significantly correlated with PD-L1 protein expression. Survival analysis demonstrated that high CD4⁺ TILs were associated with improved overall survival (OS) and disease-free survival (DFS), and furthermore, the association of high PD-L1 expression with unfavorable OS and DFS was statistically significant. Multivariate analysis identified CD4⁺ TILs and PD-L1 as prognostic markers for HNSCC. The results of the present study suggested that increased CD4⁺ TILs in HNSCC may be associated with improved outcomes, while high expression of PD-L1 may indicate unfavorable OS and DFS; thus, these factors may serve as predictors of the response to immune checkpoint therapy.

N6-Methyladenosine RNA Modification in the Tumor Immune Microenvironment: Novel Implications for Immunotherapy

N6-methyladenosine (m⁶A) methylation is one of the most common modifications of RNA in eukaryotic cells, and is mainly regulated by m⁶A methyltransferases (writers), m⁶A demethylases (erasers), and m⁶A binding proteins (readers). Recently, accumulating evidence has shown that m⁶A methylation plays crucial roles in the regulation of the tumor immune microenvironment, greatly impacting the initiation, progression, and metastasis processes of various cancers. In this review we first briefly summarizes the m⁶A-related concepts and detection methods, and then describes in detail the associations of m⁶A methylation modification with various tumor immune components especially immune cells (e.g., regulatory T cells, dendritic cells, macrophages, and myeloid-derived suppressor cells) in a variety of cancers. We discuss the relationship between m⁶A methylation and cancer occurrence and development with the involvement of tumor immunity highlighted, suggesting novel markers and potential targets for molecular pathological diagnosis and immunotherapy of various cancers.

Epstein–Barr Virus Epithelial Cancers—A Comprehensive Understanding to Drive Novel Therapies

Epstein–Barr virus (EBV) is a ubiquitous oncovirus associated with specific epithelial and lymphoid cancers. Among the epithelial cancers, nasopharyngeal carcinoma (NPC), lymphoepithelioma-like carcinoma (LELC), and EBV-associated gastric cancers (EBVaGC) are the most common. The role of EBV in the pathogenesis of NPC and in the modulation of its tumour immune microenvironment (TIME) has been increasingly well described. Much less is known about the pathogenesis and tumour–microenvironment interactions in other EBV-associated epithelial cancers. Despite the expression of EBV-related viral oncoproteins and a generally immune-inflamed cancer subtype, EBV-associated epithelial cancers have limited systemic therapeutic options beyond conventional chemotherapy. Immune checkpoint inhibitors are effective only in a minority of these patients and even less efficacious with molecular targeting drugs. Here, we examine the key similarities and differences of NPC, LELC, and EBVaGC and comprehensively describe the clinical, pathological, and molecular characteristics of these cancers. A deeper comparative understanding of these EBV-driven cancers can potentially uncover targets in the tumour, TIME, and stroma, which may guide future drug development and cast light on resistance to immunotherapy.

Efficacy, safety, and biomarker analysis of Camrelizumab in Previously Treated Recurrent or Metastatic Nasopharyngeal Carcinoma (CAPTAIN study)

BACKGROUND

This study aimed to evaluate the antitumor activity of camrelizumab, an antiprogrammed cell death-1 antibody, in pretreated recurrent or metastatic nasopharyngeal carcinoma (NPC) and to explore predictive biomarkers.

METHODS

Patients with recurrent (not amenable to locally curative treatment) or metastatic NPC who had failed at least two lines of chemotherapy were eligible to receive camrelizumab (200 mg intravenously every 2 weeks) for 2 years or until disease progression, intolerable adverse events, withdrawal of consents, or investigator decision. The primary endpoint was objective response rate (ORR) assessed by an independent review committee (IRC). Programmed cell death-ligand 1 (PD-L1) expression was assessed by immunohistochemistry. Other immune-related biomarkers including major histocompatibility complex class I and major histocompatibility complex class II (MHC-II) were assessed by multiplex immunofluorescence staining.

RESULTS

Between August 14, 2018, and December 30, 2019, a total of 156 patients were enrolled. The IRC-assessed ORR was 28.2% (95% CI 21.3% to 36.0%). The median progression-free survival was 3.7 months (95% CI 2.0 to 4.1) per IRC, and the median overall survival was 17.4 months (95% CI 15.2 to 21.9). The ORRs were 35.2% (95% CI 25.3% to 46.1%) vs 19.4% (95% CI 10.4% to 31.4%) in patients with tumor PD-L1 expression of ≥10% and<10%, respectively. Patients with durable clinical benefit (DCB), which was defined as complete response, partial response or stable disease of ≥18 weeks, had higher density of MHC-II+ cell in stroma than patients without DCB (median 868.1 (IQR 413.4-2854.0) cells/mm2 vs median 552.4 (IQR 258.4 to 1242.1) cells/mm2). MHC-II+ cell density did not correlate with PD-L1 expression, and a composite of high stromal MHC-II+ cell density and tumor PD-L1 expression further enriched patients who could benefit from camrelizumab.

CONCLUSIONS

Camrelizumab had clinically meaningful antitumor activity in patients with recurrent or metastatic NPC. The composition of both MHC-II+ cell density and PD-L1 expression could result in better patient selection.

Anti-PD-1 Therapy-A Potential Treatment for Myocardial Metastasis From Nasopharyngeal Carcinoma: A Case Report

Myocardial metastasis of nasopharyngeal carcinoma (NPC) is rarely reported in the literature. Some autopsy studies found metastases in more than 10% of cases with malignant neoplasm. However, patients are often diagnosed during the postmortem because myocardial metastasis is often asymptomatic, and its Cardiac complications tend to be severe and fatal. Patients with Cardiac metastases are often treated with chemotherapy or surgical intervention, although the prognosis is poor. Immunotherapy with anti-programmed cell death receptor-1 or ligand-1 (PD-1 or PD-L1) inhibitors has recently been reported to be therapeutically significant in multiple cancers, including melanoma, nonsmall cell lung cancer, and NPC, but the treatment of myocardial metastasis of NPC has not been reported. This study described the case of a 50-year-old male patient who presented initially with NPC and received radiotherapy as first-line therapy. For 20 years, he had recurrent Cardiac metastasis of NPC. The pathological examination suggested tPD-L1 expression. Therefore, off-label sintilimab (200 mg every 21 days) was administered. After 10 cycles of treatment, myocardial metastasis shrank and the enlarged mediastinal lymph nodes disappeared. This case report demonstrated that Cardiac metastasis of NPC expressing PD-L1 might have a sustained response to PD-L1 inhibitor-directed therapy.

Development and validation of the immune signature to predict distant metastasis in patients with nasopharyngeal carcinoma

BACKGROUND

The tumor immune microenvironment has clinicopathological significance in predicting prognosis and therapeutic efficacy. We aimed to develop an immune signature to predict distant metastasis in patients with nasopharyngeal carcinoma (NPC).

METHODS

Using multiplexed quantitative fluorescence, we detected 17 immune biomarkers in a primary screening cohort of 54 NPC tissues presenting with/without distant metastasis following radical therapy. The LASSO (least absolute shrinkage and selection operator) logistic regression model used statistically significant survival markers in the training cohort (n=194) to build an immune signature. The prognostic and predictive accuracy of it was validated in an external independent group of 304 patients.

RESULTS

Eight statistically significant markers were identified in the screening cohort. The immune signature consisting of four immune markers (PD-L1+ CD163+, CXCR5, CD117) in intratumor was adopted to classify patients into high and low risk in the training cohort and it showed a high level of reproducibility between different batches of samples (r=0.988 for intratumor; p<0.0001). High-risk patients had shorter distant metastasis-free survival (HR 5.608, 95% CI 2.619 to 12.006; p<0.0001) and progression-free survival (HR 2.798, 95% CI 1.498 to 5.266; p=0·001). The C-indexes which reflected the predictive capacity in training and validation cohort were 0.703 and 0.636, respectively. Low-risk patients benefited from induction chemotherapy plus concurrent chemoradiotherapy (IC+CCRT) (HR 0.355, 95% CI 0.147 to 0.857; p=0·021), while high-risk patients did not (HR 1.329, 95% CI 0.543 to 3.253; p=0·533). To predict the individual risk of distant metastasis, nomograms with the integration of both immune signature and clinicopathological risk factors were developed.

CONCLUSIONS

The immune signature provided a reliable estimate of distant metastasis risk in patients with NPC and might be applied to identify the cohort which benefit from IC+CCRT.

Camrelizumab versus placebo in combination with gemcitabine and cisplatin as first-line treatment for recurrent or metastatic nasopharyngeal carcinoma (CAPTAIN-1st): a multicentre, randomised, double-blind, phase 3 trial

BACKGROUND

The addition of camrelizumab to gemcitabine and cisplatin showed promising activity as first-line therapy in patients with recurrent or metastatic nasopharyngeal carcinoma in a phase 1 trial. We therefore compared camrelizumab plus gemcitabine and cisplatin with placebo plus gemcitabine and cisplatin in a randomised phase 3 trial.

METHODS

In this randomised, double-blind, phase 3 trial done at 28 hospitals in China, patients were eligible if they were aged 18-75 years, had an Eastern Cooperative Oncology Group (ECOG) performance status of 0-1, and had previously untreated recurrent or metastatic nasopharyngeal carcinoma. Patients were randomly assigned (1:1; using an interactive web-response system with a block size of four) to receive either camrelizumab (200 mg on day 1) or matching placebo intravenously, plus gemcitabine and cisplatin (gemcitabine 1000 mg/m² on days 1 and 8; cisplatin 80 mg/m² on day 1) intravenously every 3 weeks for four to six cycles, followed by maintenance therapy with camrelizumab or placebo, until radiographic progression, unacceptable toxicity, start of new anticancer treatment, investigator decision, or withdrawal of consent. Stratification factors used in randomisation were liver metastases, previous radical concurrent chemoradiotherapy, and ECOG performance status. The allocation sequence was generated by an independent randomisation group. The primary endpoint was progression-free survival per independent review committee. The significance threshold for independent review committee-assessed progression-free survival was p=0·0086 (one-sided) at the interim analysis. Efficacy and safety analyses included all patients who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, NCT03707509, and is closed for enrolment but is ongoing.

FINDINGS

Between Nov 13, 2018, and Nov 29, 2019, 343 patients were screened and 263 were eligible and were randomly assigned to the camrelizumab group (n=134) or placebo group (n=129). At the prespecified interim analysis (June 15, 2020), independent review committee-assessed progression-free survival was significantly longer in the camrelizumab group (median 9·7 months [95% CI 8·3-11·4]) than in the placebo group (median 6·9 months [5·9-7·3]; hazard ratio 0·54 [95% CI 0·39-0·76]; one-sided p=0·0002). As of Dec 31, 2020, the most common grade 3 or worse adverse events of any cause were decreased white blood cell count (89 [66%] of 134 patients in the camrelizumab group vs 90 [70%] of 129 patients in the placebo group), decreased neutrophil count (86 [64%] vs 85 [66%]), anaemia (53 [40%] vs 57 [44%]), and decreased platelet count (53 [40%] vs 52 [40%]). Serious adverse events were reported in 59 (44%) of 134 patients in the camrelizumab group and 48 (37%) of 129 patients in the placebo group. Treatment-related deaths occurred in five (4%) patients in the camrelizumab group (two unknown cause of death, one multiple organ dysfunction syndrome, one pharyngeal haemorrhage, and one arrhythmia) and one (<1%) patient in the placebo group (unknown cause of death).

INTERPRETATION

Our findings suggest that camrelizumab plus gemcitabine and cisplatin could be a new standard of care for patients with recurrent or metastatic nasopharyngeal carcinoma in the first-line setting. Longer follow-up is needed to confirm this conclusion.

FUNDING

Jiangsu Hengrui Pharmaceuticals (formerly Jiangsu Hengrui Medicine).

TRANSLATION

For the Chinese translation of the abstract see Supplementary Materials section.

Prognostic Value of Tumor Infiltrating Lymphocytes in Nasopharyngeal Carcinoma Patients: Meta-Analysis

Objective:

To evaluate the prognostic value of tumor infiltrating lymphocytes (TILs) in nasopharyngeal carcinoma (NPC) patients.

Method:

Meta-analysis was performed on eligible studies that was identified by systematic searching of Google scholar, MEDLINE, CNKI, Scopus, PubMed, PMC, Embase and Web of Science databases. The study protocol was registered in International Platform of Registered Systematic Review and Meta-Analysis Protocols-INPLASY (registration number: INPLASY202160014). Databases were searched from inception to January 20, 2020 to identify eligible studies. Those studies that evaluated survival in the form of hazard ratio (HR) in TILs of NPC patients was analyzed. All statistical analysis was performed by using STATA version 16.0 software.

Result:

Fourteen studies with a total of 3025 patients was analyzed. The pooled result showed that high TILs was significantly associated with favorable overall survival (OS) (HR = 0.55; 95%CI = 0.39-0.77; P = 0.001) and disease free survival (DFS) (HR = 0.60; 95%CI = 0.44-0.81; P = 0.04). Interestingly, high intratumoral TILs had relatively better OS (HR = 0.45; 95%CI = 0.35-0.58; P = 0.006) than stromal TILs (HR = 0.59; 95%CI = 0.36-0.97; P = 0.03). Moreover, an increased level of CD4+ cells infiltration was correlated with favorable OS (HR = 0.4; 95%CI = 0.18-0.85; P = 0.01). CD3+, CD8+ and FoxP3+ lymphocyte’s better prognosis was not statistically significant for OS (P = 0.09; P = 0.07; P = 0.52) and for DFS (P = 0.13; P = 0.29) respectively. However, subgroup analysis of intratumoral CD3+ (HR = 0.48; 95%CI = 0.33-0.70; P = 0.05) and intratumoral CD8+ (HR = 0.32; 95%CI = 0.16-0.62; P = 0.001) was significantly associated with improved OS, but not significant in stromal CD3+ (HR = 0.66; 95%CI = 0.20-2.20; P = 0.62).

Conclusion:

TILs were variably correlated with better prognosis depending on their microanatomic location and subset of TILs in NPC patients. CD4+, intratumoral CD3+ and intratumoral CD8+ lymphocytes could predict favorable patient outcome which suggest that their role in mediating antitumor immune response could potentially be exploited in the treatment of NPC patients. Future large study on the prognostic value of microanatomic location of TILs is needed for confirmation.

Current approach and novel perspectives in nasopharyngeal carcinoma: the role of targeting proteasome dysregulation as a molecular landmark in nasopharyngeal cancer

Nasopharyngeal carcinoma (NPC) represents a molecularly paradigmatic tumor given the complex diversity of environmental as well as host dependent factors that are closely implicated in tissue transformation and carcinogenesis. Epstein Barr Virus (EBV) plays a key role in tissue invasion, hyperplasia and malignant transformation. Therefore, EBV related oncoviral proteins such as Latent Membrane Protein family (LMP1, LMP2), Epstein Barr Nuclear Antigen 1 (EBNA1) and EBV related glycoprotein B (gB) are responsible for inducing intracellular signalling aberrations leading to sustained proliferation and further acquisition of NPC related invasive nature and metastatic potential.Dysregulation of proteasome signaling seems to be centrally implicated in oncoviral protein stabilization as well as in modulating tumor microenvironment. Different studies in vitro and in vivo suggest a potential role of proteasome inhibitors in the therapeutic setting of NPC. Furthermore, alterations affecting proteasome signalling in NPC have been associated to tumor growth and invasion, distant metastasis, immune exclusion and resistance as well as to clinical poor prognosis. So on, recent studies have shown the efficacy of immunotherapy as a suitable therapeutic approach to NPC. Nevertheless, novel strategies seem to look for combinatorial regimens aiming to potentiate immune recognition as well as to restore both primary and acquired immune resistance.In this work, our goal is to thoroughly review the molecular implications of proteasome dysregulation in the molecular pathogenesis of NPC, together with their direct relationship with EBV related oncoviral proteins and their role in promoting immune evasion and resistance. We also aim to hypothesize about the feasibility of the use of proteasome inhibitors as part of immunotherapy-including combinatorial regimens for their potential role in reversing immune resistance and favouring tumor recognition and eventual tumor death.

Prognostic significance of tumor-infiltrating lymphocytes and macrophages in nasopharyngeal carcinoma: a systematic review and meta-analysis

PURPOSE

Many studies have investigated the prognostic value of tumor-infiltrating lymphocytes (TILs) and tumor-infiltrating macrophages (TIMs) in patients with nasopharyngeal carcinoma (NPC), but the results remain controversial. Here, we performed a meta-analysis to evaluate the prognostic significance of TILs/TIMs in patients with NPC METHODS: The study was registered with PROSPERO (CRD42021234078). PubMed, Embase, and Web of Science databases were searched up to Dec 30, 2020. We reviewed studies that evaluated the relationship between TILs/TIMs and overall survival (OS), disease-free survival (DFS), or progression-free survival (PFS) in NPC. For TILs, CD3, CD4, CD8, and FOXP3 were searched as T-cell markers, CD19 and CD20 as B-cell markers, and CD56 as a natural killer cell marker. For TIMs, CD68 and CD163 were searched as total and M2 macrophage markers, respectively.

RESULTS

In total, 19 studies with 3708 NPC were included in this meta-analysis. We found that high total numbers of TILs were significantly associated with favorable OS [hazard ratio (HR) 0.46, 95% confidence interval (CI) 0.38-0.57 and PFS (HR 0.48, 95% CI 0.38-0.62)]. In contrast, tumor infiltration by CD3+ T cells (HR 0.55, 95% CI 0.39-0.76), CD4+ T cells (HR 0.40, 95% CI 0.18-0.85), and CD8+ T cells (HR 0.56, 95% CI 0.34-0.93) correlated positively with OS. No significant relationship was found between survival and tumor infiltration by FOXP3+ T cells, CD68+ macrophages, or CD163+ macrophages.

CONCLUSION

Our findings revealed that tumor infiltration by CD3+ , CD4+ , and CD8+ T cells could be prognostic biomarkers in NPC.

Efficacy and tolerability of immunotherapy in advanced nasopharyngeal carcinoma with or without chemotherapy: a meta-analysis

INTRODUCTION

Evidence of programmed death-1 inhibitors in nasopharyngeal carcinoma has been accumulated. However, previous clinical studies were basically small sample size.

OBJECTIVE

This study aimed to summarize existing studies to comprehensively compare programmed death-1 inhibitors in nasopharyngeal carcinoma with or without chemotherapy.

METHODS

Different databases were searched for full-text publications with a programmed death-1 inhibitor with or without chemotherapy. No study-to-study heterogeneity was detected, and fixed-effect models were applied to synthesize data.

RESULTS

Seven studies were included. The mean progression-free survival duration of programmed death-1 inhibitors treatment was 4.66 months. The 6 month progression-free survival rate was 50%, however, the12 month progression-free survival rate fell to 27%. Comparing with programmed death-1 inhibitor monotherapy, the objective response rate was higher in combination therapy (pooled RR=2.90, 95% CI: 2.07-4.08). The partial response rate was higher in patients receiving programmed death-1 in association with chemotherapy (pooled RR=3.09, 95% CI: 2.15-4.46), In contrast, the progressive disease rate was lower in combination therapy group (pooled RR=0.06, 95% CI: 0.01-0.31). Stable disease condition was comparable (pooled RR=0.90, 95% CI: 0.50-1.64) with or without chemotherapy. Programmed death-1 single use or combined with chemotherapy did not influence the total adverse events occurrence (pooled RR=0.99, 95% CI: 0.93-1.05). However, combination therapy could increase the risk of serious adverse events such as anemia, thrombocytopenia, and neutropenia.

CONCLUSION

The present study summarized the efficacy and safety of programmed death-1 inhibitors in nasopharyngeal carcinoma. Combination therapy showed higher anti-tumor activity except for higher risk of myelosuppression.

Reappraisal of the incidence, various types and risk factors of malignancies in patients with dermatomyositis and polymyositis in Taiwan

Our study aimed to investigate the incidence, risk factors and time to occurrence of malignancy in patients with dermatomyositis (DM) and polymyositis (PM). The electronic medical records of 1100 patients with DM and 1164 patients with PM were studied between January 2001 and May 2019. Malignancies after myositis were diagnosed in 61 (5.55%) patients with DM and 38 (3.26%) patients with PM. The cumulative incidence of malignancies in patients with DM were significantly higher than patients with PM (hazard ratio = 1.78, log-rank p = 0.004). Patients with DM had a greater risk of developing malignancy than those with PM at 40–59 years old (p = 0.01). Most malignancies occurred within 1 year after the initial diagnosis of DM (n = 35; 57.38%). Nasopharyngeal cancer (NPC) was the most common type of malignancy in patients with DM (22.95%), followed by lung, and breast cancers. In patients with PM, colorectal, lung and hepatic malignancies were the top three types of malignancy. The risk factors for malignancy included old age (≥ 45 years old) and low serum levels of creatine phosphokinase (CPK) for patients with DM and male sex and low serum levels of CPK for patients with PM. Low serum levels of CPK in patients with myositis with malignancy represented a low degree of muscle destruction/inflammation, which might be attributed to activation of the PD-L1 pathway by tumor cells, thus inducing T-cell dysfunction mediating immune responses in myofibers. A treatment and follow-up algorithm should explore the occurrence of malignancy in different tissues and organs and suggested annual follow-ups for at least 5.5 years to cover the 80% cumulative incidence of malignancy in patients with DM and PM.

Targeting the signaling in Epstein-Barr virus-associated diseases: mechanism, regulation, and clinical study

Epstein–Barr virus-associated diseases are important global health concerns. As a group I carcinogen, EBV accounts for 1.5% of human malignances, including both epithelial- and lymphatic-originated tumors. Moreover, EBV plays an etiological and pathogenic role in a number of non-neoplastic diseases, and is even involved in multiple autoimmune diseases (SADs). In this review, we summarize and discuss some recent exciting discoveries in EBV research area, which including DNA methylation alterations, metabolic reprogramming, the changes of mitochondria and ubiquitin-proteasome system (UPS), oxidative stress and EBV lytic reactivation, variations in non-coding RNA (ncRNA), radiochemotherapy and immunotherapy. Understanding and learning from this advancement will further confirm the far-reaching and future value of therapeutic strategies in EBV-associated diseases.

PD-L1 Expression is Highly Associated with Tumor-Associated Macrophage Infiltration in Nasopharyngeal Carcinoma

Purpose

Tumour-associated macrophages (TAMs) are the most abundant immune cells in the tumor microenvironment and provide a barrier against the cytotoxic effector functions of T cells and natural killer (NK) cells. Recently, TAMs have become increasingly recognised as an attractive target in combination therapy with PD-1/PD-L1 immuno-checkpoint blockades (ICBs). However, the relationship between PD-L1 expression and TAMs remains unknown in nasopharyngeal carcinoma (NPC).

Patients and Methods

A total of 212 NPC patients from Nanfang hospital were collected in this study. We evaluated the expression of PD-L1 in tumor cells, CD68 (pan-macrophages), and CD163 (M2-like macrophage) in NPC tissues using immunohistochemical (IHC) staining.

Results

The positivity of PD-L1 on tumor cells was 61.3% (130/212). The infiltration densities of CD68+ cells and CD163+ cells in PD-L1-positive NPC tissues were significantly higher than those in PD-L1-negative NPC tissues (P=0.0012 for CD68; P<0.0001 for CD163). Logistic regression analysis showed that high densities of CD68+ macrophages and CD163+ TAMs were significantly associated with increased PD-L1 expression. Subgroup analyses demonstrated that a positive PD-L1 expression on tumor cells in combination with lower CD163+ TAMs density was significantly associated with favorable prognosis, whereas negative PD-L1 expression on tumor cells with higher CD163+ TAMs density was associated with worse prognosis.

Conclusion

The PD-L1 expression in tumor cells was positively correlated with TAMs density in tumor microenvironment of NPC, suggesting TAMs as a new target for combination therapy to improve the response rate of ICBs in NPC treatment.

Recent Advances in the Development of Biomarkers and Chemoradiotherapeutic Approaches for Nasopharyngeal Carcinoma

Epstein-Barr virus (EBV) associated nasopharyngeal carcinoma (NPC) is endemic in Southern China, and the prognosis of this cancer has improved in part due to advances in radiotherapy (RT) techniques, broadened therapeutic options, and more precise prognostic stratification of patients. RT is the primary curative treatment of NPC, and the incorporation of chemotherapy (induction, concurrent, adjuvant) to RT has contributed to improved survival in patients with locoregionally advanced NPC. Concurrent chemoradiotherapy (CCRT) in combination with adjuvant or induction chemotherapy is now the standard treatment of locoregionally advanced NPC, but the ideal CCRT therapeutic strategy for NPC remains controversial. Plasma EBV DNA is the archetypal tumor-derived DNA in NPC, and three generations of studies have gradually expanded its clinical applications. Recently, the advent of whole exome/genome sequencing of NPC and the promising clinical activity of immune checkpoint inhibitors have also spurred interest in the development of newer biomarkers. This review will focus on two clinical advances in NPC research that have made substantial impact on the contemporary management of NPC: (1) The integration of plasma EBV DNA in an expanding spectrum of clinical indications, and the development of promising immune-related biomarkers; (2) the current development of CCRT with special emphasis on the use of induction and adjuvant chemotherapy, as well as the potential applications of metronomic chemotherapy and immune checkpoint inhibitors in the treatment of locoregionally advanced NPC.

Comparison of whole exome sequencing in circulating tumor cells of primitive and metastatic nasopharyngeal carcinoma

BACKGROUND

Nasopharyngeal carcinoma (NPC) is one of the most common cancers. To investigate the gene mutation profile of NPC patients, we performed whole exome sequencing (WES) in tumor cells, peripheral blood cells, and circulating tumor cells (CTCs) of primitive and metastatic NPC patients, and explored its clinical significance.

METHODS

Primitive tumor cells, white blood cells, and CTCs of patients were collected and hybridized with probes targeting whole exons. Mutational signatures, signaling pathways, and cancer associated genes from CTCs cells of two primitive and two metastatic patients were analyzed using gene ontology (GO) method.

RESULTS

The mutational landscape of four primitive tumors showed that there were more MSH2 alterations in more non-silent mutation number patients Additionally, BAP1 gene mutation only occurred in metastatic patients. The most frequently mutated genes among the primitive tumor and CTC samples were CFAP74, MOB3C, PDE4DIP, IGFN1, CYFIP2, NOP16, SLC22A1, ZNF117, and SSPO. Interestingly, only PMS1, BRIP1, DEE, OR2T12, CPN2, MLXIPL, BAIAP3, IGSF3, SIN3B, and ZNF880 alterations occurred in primary tumors of metastatic patients. Primitive and metastatic NPC had significantly distinct mutational signatures. GO analysis revealed that each patient had his own mutational signaling pathways. Non-silent single nucleotide variations (non-silent SNVs) and insertion-deletion mutations (INDELs) in CTCs were more dramatic than in primitive tumor cells.

CONCLUSIONS

These changes are strongly relevant to their clinical characteristics and therapeutic strategy.

Gene Signatures and Prognostic Values of m6A Genes in Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is a malignant tumor with a high rate of local invasion and early distant metastasis. Accumulating studies suggest that N6-methyladenosine methylation (m⁶A) is closely related to tumorigenesis. However, the relationship between m⁶A-related genes and prognosis of NPC is poorly understood. Our research aims to discover the prognostic value of m⁶A RNA methylation genes in NPC. In this study, we analyzed the differentially expressed m⁶A-related genes between NPC samples and normal control samples and found that two upregulated genes (YTHDF3 and IGF2BP2) and one downregulated gene (METTL3) were overlapped in GSE68799 and GSE53819. Next, we found that high expression of IGF2BP1 and low expression of METTL3 and YTHDF3 in NPC patients showed poor progression-free survival (PFS). Subsequently, the four m⁶A genes were selected for consensus cluster analysis, and risk models were established. The risk signature, using three genes (GF2BP1 + IGF2BP2 + METTL3), was an independent prognostic factor and predicts the clinicopathological features of NPC. Additionally, the GO, KEGG analysis, and CIBERSORT algorithm revealed that the risk signature was closely associated to immune infiltration in NPC. Finally, the expression and clinical significance of METTL3 were successfully validated in NPC tissues using immunohistochemical techniques. In conclusion, our finding revealed the potential role of m⁶A modification in NPC, providing novel insight into NPC prognosis and therapeutic strategies.

Long-term outcomes and safety after reirradiation in locally recurrent nasopharyngeal carcinoma in a non-endemic area

PURPOSE

To determine outcomes and toxicities after reirradiation for locally recurrent nasopharyngeal carcinoma (rNPC) and to apply a prognostic index in a non-endemic region.

METHODS

We retrospectively reported progression-free survival (PFS), overall survival (OS), and treatment-related toxicities in patients treated with curative intent for locally rNPC. We applied the prognostic model for OS and grade 5 radiotherapy (RT)-related toxicities published by Li et al. and evaluated its prognostic accuracy by receiver operating characteristic (ROC) curve analysis.

RESULTS

Between 2005 and 2018, 33 patients were treated for rNPC in our institution. Median follow-up was 60 months. The mean time to local recurrence was 75 months. Six (18%) patients had a persistent grade 3 toxicity from a previous RT course. The median re-RT dose was 66 Gy. After re-RT, 13 patients had local failure and 3 patients had metastatic recurrence. Median PFS was 18 months with a 5-year PFS rate of 29%. Median OS was 35 months with a 5-year OS rate of 37%. Grade 3 or higher toxicities rate was 74%. There were 21% grade 5 toxicities. The median time to a grade 5 toxicity was less than 6 months following re-RT. The prognostic nomogram was not predictive for OS or grade 5 toxicities.

CONCLUSION

Reirradiation of rNPC is an effective treatment but is associated with a high rate of life-threatening toxicity. Stratification of patients based on their risk of developing severe toxicity is needed to select patients who will most likely benefit from re-RT.

Optimal cumulative dose of cisplatin for concurrent chemoradiotherapy among patients with non-metastatic nasopharyngeal carcinoma: a multicenter analysis in Thailand

BACKGROUND

Chemoradiotherapy (CRT) with high cumulative doses (CDs) of cisplatin has been considered the standard of care for non-metastatic nasopharyngeal carcinoma (NPC). However, given most patients' inability to tolerate high CDs due to cisplatin-related toxicities, the optimal CD of cisplatin during CRT remains undetermined.

METHODS

Patients with non-metastatic NPC who received CRT with cisplatin between 2007 and 2017 were identified through the Thai head and neck cancer multicenter database and then categorized according to cisplatin CD (mg/m2) received. All complications and cisplatin-related toxicities during CRT were recorded.

RESULTS

We identified 779 non-metastatic NPC patients receiving low (≤150; n = 97), intermediate (151-250; n = 411), and high (> 250; n = 271) CDs of cisplatin. Low CD patients had significantly lower mean actual radiation dose (p < 0.001) and more radiotherapy delay (p = 0.010), while intermediate CD patients had the least hospitalization (p < 0.001). Overall, 39.3% of the patients experienced cisplatin-related toxicity, which was associated with poor overall survival (OS) (p = 0.001). Acute kidney injury was observed in 7% in all patients, which was highest among low CD patients (15.5%; p = 0.002). Intermediate CD patients had significantly longer median OS than the low and high groups (64 vs. 49.8 vs. 53.2, respectively; p = 0.015). Univariate, but not multivariate, analysis showed that CD of cisplatin was significantly associated with OS.

CONCLUSION

CD of cisplatin during CRT was not an independent prognostic factor for OS. An intermediate CD induced minimal toxicity without compromising survival and should be considered the optimal CD. Nonetheless, a randomized phase 3 study evaluating the optimal CD of cisplatin is warranted.

Immune landscape in Burkitt lymphoma reveals M2-macrophage polarization and correlation between PD-L1 expression and non-canonical EBV latency program

BACKGROUND

The Tumor Microenviroment (TME) is a complex milieu that is increasingly recognized as a key factor in multiple stages of disease progression and responses to therapy as well as escape from immune surveillance. However, the precise contribution of specific immune effector and immune suppressor components of the TME in Burkitt lymphoma (BL) remains poorly understood.

METHODS

In this paper, we applied the computational algorithm CIBERSORT to Gene Expression Profiling (GEP) datasets of 40 BL samples to draw a map of immune and stromal components of TME. Furthermore, by multiple immunohistochemistry (IHC) and multispectral immunofluorescence (IF), we investigated the TME of additional series of 40 BL cases to evaluate the role of the Programmed Death-1 and Programmed Death Ligand-1 (PD-1/PD-L1) immune checkpoint axis.

RESULTS

Our results indicate that M2 polarized macrophages are the most prominent TME component in BL. In addition, we investigated the correlation between PD-L1 and latent membrane protein-2A (LMP2A) expression on tumour cells, highlighting a subgroup of BL cases characterized by a non-canonical latency program of EBV with an activated PD-L1 pathway.

CONCLUSION

In conclusion, our study analysed the TME in BL and identified a tolerogenic immune signature highlighting new potential therapeutic targets.

Establishment and Characterization of Humanized Mouse NPC-PDX Model for Testing Immunotherapy

Immune checkpoint blockade (ICB) monotherapy shows early promise for the treatment of nasopharyngeal carcinoma (NPC) in patients. Nevertheless, limited representative NPC models hamper preclinical studies to evaluate the efficacy of novel ICB and combination regimens. In the present study, we engrafted NPC biopsies in non-obese diabetic-severe combined immunodeficiency interleukin-2 receptor gamma chain-null (NSG) mice and established humanized mouse NPC-patient-derived xenograft (NPC-PDX) model successfully. Epstein–Barr virus was detected in the NPC in both NSG and humanized mice as revealed by Epstein–Barr virus-encoded small RNA (EBER) in situ hybridization (ISH) and immunohistochemical (IHC) staining. In the NPC-bearing humanized mice, the percentage of tumor-infiltrating CD8⁺ cytotoxic T cells was lowered, and the T cells expressed higher levels of various inhibitory receptors, such as programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) than those in blood. The mice were then treated with nivolumab and ipilimumab, and the anti-tumor efficacy of combination immunotherapy was examined. In line with paired clinical data, the NPC-PDX did not respond to the treatment in terms of tumor burden, whilst an immunomodulatory response was elicited in the humanized mice. From our results, human proinflammatory cytokines, such as interferon-gamma (IFN-γ) and interleukin-6 (IL-6) were significantly upregulated in plasma. After treatment, there was a decrease in CD4/CD8 ratio in the NPC-PDX, which also simulated the modulation of intratumoral CD4/CD8 profile from the corresponding donor. In addition, tumor-infiltrating T cells were re-activated and secreted more IFN-γ towards ex vivo stimulation, suggesting that other factors, including soluble mediators and metabolic milieu in tumor microenvironment may counteract the effect of ICB treatment and contribute to the tumor progression in the mice. Taken together, we have established and characterized a novel humanized mouse NPC-PDX model, which plausibly serves as a robust platform to test for the efficacy of immunotherapy and may predict clinical outcomes in NPC patients.

CD3+T-lymphocyte infiltration is an independent prognostic factor for advanced nasopharyngeal carcinoma

Background

Locally advanced nasopharyngeal carcinoma (LA-NPC) is a relatively rare disease in the west but more common in East Asia and areas of the Middle East like Saudi Arabia. Despite the advances in radiation therapy techniques, some patients relapse after treatment. In the coming era of cancer immunotherapy, prognostic factors for LA-NPC need to be further defined using immune-relevant markers. Several markers are available; however, the most robust and accessible/affordable marker is not well-defined.

Methods

Retrospectively, tumor-infiltrating lymphocytes (TIL), their subsets as well as tumoral PD-L1 expression were analyzed in tumor tissues from 63 LA-NPC patients treated with platinum-based concurrent chemo-radiotherapy (CCRT) in addition to 20 cases with metastatic (MET) disease. Immunostaining was done using a validated and fully automated system. Scoring was done by two independent pathologists and results were compared.

Results

There was no statistical difference between LA-NPC and MET disease in terms of CD3+, CD8+ TIL infiltration, or tumoral PD-L1 expression.

In LA-NPC, low CD3+ TIL infiltration highly correlated with shorter disease-free survival (DFS, HR = 8.5, p = < 0.001) and overall survival (OS, HR = 13, p = 0.015) with substantial agreement between scoring pathologists. A similar correlation was found between low CD8+ TIL and survival. Correlation of total TIL was significant with DFS (HR = 4.0, p = 0.008), borderline with OS and the correlation was dependent on the scoring pathologist. Having histological WHO type I&II correlated significantly with shorter DFS (HR 4.03, p = 0.008) and low CD3+ TIL (p = 0.009). Subgroup analysis of LA-NPC that included undifferentiated type (WHO type III) cases only (n = 58), showed a strong correlation between low CD3+ TIL and shorter DFS (HR = 7.2, p = < 0.001) and OS (HR = 17.3, p = 0.008). PD-L1 was expressed in 72% of type III LA-NPC cases while lacking PD-L1 expression correlated with shorter OS (HR = 6.1, p = 0.031). Patients with a combination of low CD3+ TIL and lack of PD-L1 expression had the worst OS (p < 0.001).

Conclusions

CD3+ TIL is promising as a robust and independent prognostic marker for DFS and OS of LA-NPC patients treated with platinum-based CCRT. We would suggest the use of CD3 + TIL as a stratifying factor for LA-NPC, which warrants further validation in prospective trials.

The Prognostic Significance of APOBEC3B and PD-L1/PD-1 in Nasopharyngeal Carcinoma

PURPOSE

Apolipoprotein B mRNA editing enzyme catalytic polypeptide-like 3B (APOBEC3B) is a recently discovered protein that is considered important in causing mutations in tumor cell genome bases. Whether APOBEC3B is expressed in nasopharyngeal carcinoma (NPC) still remains unknown. Studies have shown that programmed-cell-death receptor-1 ligand (PD-L1) is highly expressed in NPC, but its clinical significance has not been fully elucidated. We aimed to evaluate APOBEC3B and PD-L1 protein expression in NPC and also investigate their prognostic significance.

MATERIALS AND METHODS

One hundred and three patients with NPC were retrospectively collected in this study, and were followed-up for 5 years. The expression of APOBEC3B and PD-L1/PD-1 in NPC was detected by immunohistochemical staining.

RESULTS

High expression of APOBEC3B was observed in 42.7% of NPC patients. The high expression rate of APOBEC3B was 31.5% in patients without recurrence or metastasis within 5 years, and 55.1% in those patients with recurrence or metastasis, and the difference was statistically significant (P=0.016). There was no significant difference in APOBEC3B expression among patients with different sex, age group, and clinical stage (P>0.05). The positive expression rate of PD-L1 was 55.3% in all patients with NPC. There was no significant difference in PD-L1 expression among patients with different sex, age group, clinical stage, and tumor recurrence or metastasis condition (P> 0.05). There was no significant correlation between the expression of APOBEC3B and PD-L1 in NPC patients. The positive expression rate of PD-1 was 1.9% (2/103) in patients with NPC.

CONCLUSIONS

APOBEC3B showed association with aggressive behavior and poor outcome in NPC, and is also considered as a potential marker for predicting NPC recurrence or metastasis. PD-L1 is not associated with the aggressive behavior and poor outcome in NPC.

Tumor microenvironment predicts local tumor extensiveness in PD-L1 positive nasopharyngeal cancer

Tumor microenvironment have been implicated in many kind of cancers to hold an important role in determining treatment success especially with immunotherapy. In nasopharyngeal cancer, the prognostic role of this immune cells within tumor microenvironment is still doubtful. We conducted a study that included 25 nasopharyngeal cancer biopsy specimens to seek a more direct relationship between tumor infiltrating immune cells and tumor progression. Apart from that, we also checked the PD-L1 protein through immunohistochemistry. The PD-L1 was positively expressed in all our 25 samples with nasopharyngeal cancer WHO type 3 histology. Majority samples have >50% PD-L1 expression in tumor cells. We also found that denser local tumor infiltrating immune cells population have relatively much smaller local tumor volume. The inverse applied, with the mean local tumor volumes were 181.92 cm3 ± 81.45 cm3, 117.13 cm3 ± 88.72 cm3, and 55.13 cm3 ± 25.06 cm3 for mild, moderate, and heavy immune cells infiltration respectively (p = 0.013). Therefore, we concluded that tumor infiltrating immune cells play an important role in tumor progression, hence evaluating this simple and predictive factor may provide us with some valuable prognostic information.

Expression and clinical significance of PD-L1 and BRAF expression in nasopharyngeal carcinoma

Background

The prognostic value of programmed death-ligand 1 (PD-L1) and BRAF expression in nasopharyngeal carcinoma (NPC) is not well-defined. In this study we investigated alterations in PD-L1, BRAF and EGFR by using immunohistochemistry analysis in a cohort of consecutively enrolled NPC patients.

Methods

A retrospective review of 154 NPC patients form our previous study (BMC Cancer. 2013; 13:226) were conducted. Survival and prognostic impacts were analyzed based on PD-L1, BRAF and EGFR expression levels.

Results

One hundred fifty four patients were included in this study. PD-L1 expression was detected in 87.7% of patients; 14.3% had 1–5% PD-L1 expression, 47.4% had 5–49% expression while 26% had ≥50% expression Higher PD-L1 expression was significantly associated with shorter PFS and OS. The median PFS was 25 months (95% CI 15.7–34.3 months) and OS was 35 months (95% CI 22.60–47.4 months) for patients with PD-L1 expression ≥50%; both median PFS and OS were not yet reached for patients with PD-L1 expression < 50%. PFS was significantly higher in BRAF mutation positive patients (5-year PFS: 55.1% vs. 30.8%, P = 0.044).

Conclusion

Tumor PD-L1 expression and BRAF mutation are associated with poor outcomes in patients with NPC. This study was retrospectively registered in ClinicalTrials.gov (NCT03989297) on 2019-6-18.

Prognostic Value of Programmed Cell Death Ligand-1 Expression in Nasopharyngeal Carcinoma: A Meta-Analysis of 1,315 Patients

Background: The prognostic value of programmed cell death ligand-1 (PD-L1) in patients with nasopharyngeal carcinoma (NPC) remains controversial. Therefore, we conducted this meta-analysis to understand the role of PD-L1 in NPC.

Method: We searched PubMed, Embase, Web of Science, and Cochrane Library up to April 2019. We determined the pooled hazard ratio (HR) and 95% confidence intervals (CIs) to assess the relationship between PD-L1 and various survival outcomes. Begg's funnel plot was used to assess any publication bias.

Results: Eleven studies involving 1,315 patients were included in this meta-analysis. For overall survival (OS), the HR was 1.48 and 95% CI was 1.00–2.18 (p = 0.049). For disease-free survival (DFS), the HR was 1.51 and 95% CI was 0.85–2.69 (p = 0.162). For distant metastasis-free survival (DMFS), the HR was 1.75 and 95% CI was 0.64–4.79 (p = 0.277). For local recurrence-free survival (LRFS), the HR was 0.67 and 95% CI was 0.06–8.16 (p = 0.756). The results of prognosis of PD-L1 and OS were more significant after sensitivity analysis. The pooled odds ratio indicated that PD-L1 expression was not associated with T stage, N stage, M stage, overall stage, sex, age, smoking, or alcohol intake. No publication bias was found.

Conclusion: Our meta-analysis showed that PD-L1 overexpression in NPC was associated with a poor OS and may be useful as a novel prognostic factor for NPC.

Expression of PD-1 and PD-Ls in Kaposi's sarcoma and regulation by oncogenic herpesvirus lytic reactivation

Kaposi's sarcoma-associated herpesvirus (KSHV) causes several cancers such as Kaposi's sarcoma (KS) and primary effusion lymphoma (PEL). PD-1/PD-Ls immune checkpoint molecules play important roles in cancer cell immune escape. The expression of PD-1/PD-Ls and their regulation by oncogenic viruses, in particular KSHV, remain largely undefined. Here we demonstrate strong PD-1/PD-L1/PD-L2 expression in KS tissues from a cohort of HIV + patients. We found that induction of KSHV lytic reactivation significantly upregulates PD-L1 expression on infected tumor cells, potentially through several major cellular signaling pathways and IL-1β, which may represent a novel mechanism for virus-associated tumor cell immune escape.

Programmed Cell Death 1 and Programmed Cell Death Ligands in Extranodal Natural Killer/T Cell Lymphoma: Expression Pattern and Potential Prognostic Relevance

The programmed cell death 1/programmed cell death ligands (PD-1/PD-Ls) axis is a potential immune escape mechanism of cancers. However, data on the PD-1/PD-Ls pathway in EBV-associated extranodal natural killer/T cell lymphoma (ENKTL) and its clinical implication are limited. Herein, we characterized PD-1/PD-L expression and its prognosis relevance in 49 ENKTL patients in Thailand. PD-L1 was expressed frequently on both lymphoma cells (61.2%) and stroma (77.5%), whereas PD-L2 expression was more common on lymphoma (63.2%) than stromal cells. PD-1 was positive in 20.5% of stroma, but undetectable on lymphoma cells. There was no association between baseline clinical characteristics and the expression PD-1/PD-Ls. The survival of patients with PD-Ls on tumor cells was poor. For PD-L1-positive versus negative cases, the 2-year event-free survival (EFS) was 42.2 versus 71.8% (p = 0.03) and 2-year overall survival (OS) was 45.4 versus 78.9% (p = 0.02), respectively. Comparing between patients with PD-L2-positive and PD-L2-negative lymphoma, the 2-year EFS was 37.1 versus 82.4% (p = 0.02) and 2-year OS was 45.2 versus 82.4% (p = 0.03), respectively. Neither PD-1 nor PD-Ls expression in the stroma predicted outcomes. In conclusion, PD-Ls were frequently expressed on ENKTL cells and associated with inferior outcomes. Therefore, PD-Ls are potential prognostic biomarkers and the roles of immune checkpoint blockade therapy in ENKTL deserve further investigation.

Future of Radiotherapy in Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is a malignancy with unique clinical biological profiles such as associated Epstein-Barr virus infection and high radiosensitivity. Radiotherapy has long been recognized as the mainstay for the treatment of NPC. However, the further efficacy brought by radical radiotherapy has reached the bottleneck in advanced patients, who are prone to develop recurrence and distant metastasis after treatment. The application of photon therapy makes it possible for radiation dose escalation in refractory cases and may provide second chance for recurrent patients with less unrecoverable tissue damage. The concept of adaptive radiotherapy is put forward in consideration of target volume shrinkage during treatment. The replanning procedure offers better protection for the organ at risk. However, the best timing and candidates for adaptive radiotherapy is still under debate. The current tendency of artificial intelligence in NPC mainly focuses on image recognition, auto-segmentation and dose prediction. Although artificial intelligence is still in developmental stage, the future of it is promising.To further improve the efficacy of NPC, multimodality treatment is encouraged. In-depth studies on genetic and epigenetic variations help to explain the great heterogeneity among patients, and could further be applied to precise screening and prediction, personalized radiotherapy and the evolution of targeted drugs. Given the clinical benefit of immunotherapy in other cancers, the application of immunotherapy, especially immune checkpoint inhibitor, in NPC is also of great potential. Results from ongoing clinical trials combining immunotherapy with radiotherapy in NPC are expected.

Nasopharyngeal carcinoma

Nasopharyngeal carcinoma is characterised by distinct geographical distribution and is particularly prevalent in east and southeast Asia. Epidemiological trends in the past decade have shown that its incidence has declined gradually but progressively, and mortality has been reduced substantially. These findings probably reflect lifestyle and environmental changes, enhanced understanding of the pathogenesis and risk factors, population screening, advancements in imaging techniques, and individualised comprehensive chemoradiotherapy strategies. In particular, plasma Epstein-Barr virus (EBV) DNA has been used for population screening, prognostication, predicting treatment response for therapeutic adaptation, and disease surveillance. Moreover, the widespread application of intensity-modulated radiotherapy and optimisation of chemotherapy strategies (induction, concurrent, adjuvant) have contributed to improved survival with reduced toxicities. Among the existing developments in novel therapeutics, immune checkpoint therapies have achieved breakthroughs for treating recurrent or metastatic disease and represent a promising future direction in nasopharyngeal carcinoma.

PD-1 high expression predicts lower local disease control in stage IV M0 nasopharyngeal carcinoma

BACKGROUND

Tumor-infiltrating lymphocytes (TILs) play a critical role in tumor immune surveillance and immune suppression. Understanding tumor infiltrating T cell subset density, location and PD-1/PD-L1 expression might provide insight for the prediction of tumor therapeutic response and clinical outcome. The purpose of this study was to evaluate the expression and localization of CD8, FoxP3, PD-1, and PD-L1 in primary tumor tissues and their effects on prognosis of stage IV M0 locally advanced nasopharyngeal carcinoma (NPC) patients.

METHODS

Sixty NPC patients with stage IV M0 locally advanced disease were treated with definitive chemoradiation. Tumor biopsies from primary lesion were analyzed for the expression and localization of CD8, FoxP3, PD-1, and PD-L1 by immunohistochemistry. Their associations with local disease control and survival of NPC were analyzed.

RESULTS

The average follow-up time was 43 months (range from 14 to 61 months). High expression of CD8^+, FoxP3⁺, PD-1⁺ and PD-L1⁺ was observed in 60, 86.7, 56.7, and 91.7% of patients, respectively. There was no correlation between clinicopathological features and the expression of these immune markers. High PD-1 expression was found to be associated with lower local disease control (5-year LRFS 23.2% vs 96.8%, p < 0.001) and unfavorable clinical outcome (5-year OS 47.4% vs 73.3%, p = 0.014). In multivariate analysis, PD-1 expression was also an adverse prognostic factor for 5-year OS (HR: 3.68, P = 0.023) and LRFS (HR: 16.89, 1.27-11.84, P = 0.007). Those with PD-1 distribution in both stroma and tumor region had the poorest prognosis. However, PD-1 expression has no significant correlation with 5-year RRFS (p = 0.980) and DMFS (p = 0.865). Patients with both PD-1 and PD-L1 high expression had significant poor local disease control (5-year LRFS 96.0% vs 43.0%, p < 0.001) and overall survival (5-year OS 80.8% vs 45.1%, p < 0.001) compared with the others. Other immune markers were not found having corrections with disease control and survival.

CONCLUSIONS

PD-1 high expression, especially with PD-L1 co-expression, is associated with high local recurrence and unfavorable clinical outcome for stage IV M0 NPC patients, and might be a potential target for immunotherapy.

The prognostic significance of PD-L1 and PD-1 expression in patients with nasopharyngeal carcinoma: a systematic review and meta-analysis

Background

Whether PD-L1/PD-1 expression plays a significant role in the prognosis of NPC is still controversial. The present study mainly aimed to investigate the prognostic significance of PD-L1/PD-1 expression in patients with NPC.

Methods

A systematical research was performed in the PubMed, Web of Science, EMBASE, and the Cochrane Library databases up to January 06, 2019. Eighteen studies met eligible criteria were included in the meta-analysis. Quality assessment of included articles was evaluated by Newcastle–Ottawa quality assessment scale (NOS). Pooled hazard ratios (HRs) and their corresponding 95% confidence intervals (95% CIs) were used to elucidated the primary endpoint, overall survival (OS), and the secondary endpoints. Furthermore, the relationship between clinicopathological features of NPC and PD-L1/PD-1 expression was estimated by relative ratios (RRs) and 95% CIs.

Results

A total of 1836 patients from 15 included studies concerning PD-L1 and 678 patients from six studies regarding PD-1 were included in the meta-analysis. Pooled results revealed that PD-L1 expression in NPC did not correlate with OS (HR 1.34 95% CI 0.93–1.93, p = 0.11), DFS (HR 1.82, 95% CI 0.86–3.85, p = 0.12), PFS (HR 1.19, 95% CI 0.46–3.08, p = 0.72), and DMFS (HR 2.26, 95% CI 0.60–8.56, p = 0.23). Meanwhile, no statistically significant differences existed between the expression level of PD-1 in tumor infiltrating lymphocytes (TILs) and the OS in NPC, with the pooled HR 1.29 (95% CI 0.68–2.42, p = 0.44). In subgroup analysis, higher expression of PD-L1 in immune cells correlated with better OS in patients with NPC, with a pooled HR 0.68 (95% CI 0.47–0.99, p = 0.04). Among the clinicopathological features included in our study, we found that the positive expression of PD-L1 in NPC associated with the higher expression of PD-1 (RR 1.25, 95% CI 1.02–1.52, p = 0.03).

Conclusions

Our meta-analysis indicated that higher/positive expression of PD-L1/PD-1 may not serve as suitable biomarkers for the prognosis of NPC, which was not in consistent with some previous studies about the prognostic value of PD-L1/PD-1 in other types of tumors. Despite the positive results in subgroup analysis and study about clinicopathological features, it may still need corroboration of prospective and large-scale studies.

Electronic supplementary material

The online version of this article (10.1186/s12935-019-0863-5) contains supplementary material, which is available to authorized users.

Changes in plasma EBV-DNA and immune status in patients with nasopharyngeal carcinoma after treatment with intensity-modulated radiotherapy

BACKGROUND

Previous studies reported the early diagnostic values of plasma Epstein-Barr virus (EBV)-DNA. The present study aimed to assess the relationship between the concentration of plasma EBV-DNA and the number of CD8⁺PD-1⁺(programmed cell death-1,PD-1) and regulatory T (Treg) cells in patients with nasopharyngeal carcinoma (NPC) who were treated with intensity-modulated radiotherapy (IMRT).

METHODS

This study included 37 patients treated with IMRT. Peripheral blood samples were collected two times for each patient, before radiation therapy and 1 week after the treatment. Further, the numbers of CD4⁺, Treg, CD8⁺, and CD8⁺PD1⁺ cells were determined by flow cytometry.

RESULTS

The changes after IMRT were determined by comparing the numbers of neutrophils, lymphocytes, CD4⁺, Treg, CD8⁺, CD8⁺PD1⁺ cells, and the concentration of plasma EBV-DNA between pretreatment and post-treatment groups. IMRT could reduce the expression level of PD-1 and the number of Treg cells. The concentration of plasma EBV-DNA and the expression level of CD8⁺PD-1⁺ were closely associated with the occurrence and development of NPC. Thus, EBV-DNA can be used as an important marker for early diagnosis, and IMRT can strongly reduce the copies of EBV-DNA.

CONCLUSIONS

This study showed that IMRT could reverse T-cell exhaustion and reduce the copies of EBV-DNA. In clinical practice, plasma EBV-DNA is a sensitive biomarker for diagnosis, prognosis, and evaluation of clinical efficacy.

Prognostic value of immune checkpoint molecules in head and neck cancer: a meta-analysis

Immune checkpoint molecules are important targets in cancer immunotherapy, but their association with prognosis in patients with head and neck cancer is controversial. In this meta-analysis, we searched for 12 immune checkpoint molecules in the PubMed, Embase and Cochrane Library databases and retrieved 52 studies with 7127 participants. Among the molecules included in the search, indoleamine 2, 3-dioxygenase (IDO), programmed death ligand 1 (PD-L1), and programmed death 1 (PD-1) met the inclusion criteria for further analysis. Higher expression of IDO was associated with poorer overall survival in head and neck cancer patients (P = 0.011), but higher expression of PD-L1 correlated with better overall survival specifically in nasopharyngeal carcinoma patients (P = 0.01). In a sensitivity analysis, higher PD-L1 expression correlated with better progression-free survival (P = 0.043), and was associated with better overall survival in Caucasian subjects (P = 0.02), nasopharyngeal carcinoma patients (P = 0.015), and studies with small sample sizes (P = 0.001). PD-1 had no prognostic significance. There was no publication bias affecting the results. Thus, among the immune checkpoint molecules, IDO and PD-L1 are potential prognostic predictors in head and neck cancer.