Influence of PD-L1 expression in immune cells on the response to radiation therapy in patients with oropharyngeal squamous cell carcinoma

SOX13 as a potential prognostic biomarker linked to immune infiltration and ferroptosis inhibits the proliferation, migration, and metastasis of thyroid cancer cells

Background

SOX13 is a transcription factor belonging to the SOX family. SOX proteins are critical regulators of multiple cancer progression, and some are known to control carcinogenesis. Nevertheless, the functional and clinical significance of SOX13 in human thyroid cancer (THCA) remain largely unelucidated.

Methods

Data on SOX13 expression were obtained through The Cancer Genome Atlas together with Gene Expression Omnibus. Co-expression, differential expression, and functional analyses of genes were investigated by databases. Associations between SOX13 levels, immune infiltration, ferroptosis, and immune checkpoint gene levels were analyzed. Genetic changes in SOX13 were investigated using CBioPortal. Associations between SOX13 levels and THCA clinicopathological features were analyzed and nomogram modeling for diagnostic and prognostic prediction. The influence of SOX13 on proliferation, migration, and metastasis was determined in KTC-1 and TPC-1 cell lines.

Results

SOX13 was significantly lower in THCA tumors compared to controls. In addition, upregulated SOX13 gene mutation were evident in thyroid cancer. SOX13-associated genes exhibited differential expression in pathways associated with thyroid cancer development. Significant associations were found between SOX13 levels, immune infiltration, ferroptosis, and immune checkpoint genes in THCA tissue. SOX13 levels correlated with THCA stage, histologic grade, and primary neoplasm focus types, and independently predicted overall and progression-free intervals. SOX13 expression effectively distinguished between tumor and normal thyroid tissue. Spearman correlations highlighted a significant relationship between SOX13 and ferroptosis-associated genes. Overexpression of SOX13 enhances the inhibition of RSL3 (iron death activator) on the cell viability of TPC-1. Higher SOX13 levels in Thyroid cancer cells may lead to reduced proliferation, migration, and metastasis by regulating ferroptosis.

Conclusion

Reduced SOX13 expression inversely impacts patient prognosis. In addition, SOX13 strongly regulates cancer immunity and Ferroptosis. Hence, SOX13 has great promise as a bioindicator for both thyroid cancer prognosis and immune cell invasion.

Prediction of Treatment Response Based on Nutritional Status and Tumor Immunity in Oropharyngeal Cancer Patients Treated With Chemoradiotherapy

Background/Aim

Radiotherapy (RT) for advanced oropharyngeal cancer (OPC) is effective, especially when combined with chemotherapy (CRT). However, its success can vary depending on factors, such as tumor stage, HPV infection (p16 status), and the patient's nutritional and immune status. This study examined the controlling nutritional status (CONUT) score and tumor immunity as predictive factors for treatment outcomes in OPC, aiming to develop a personalized risk score.

Patients and Methods

A retrospective analysis was conducted on 84 patients with OPC treated with definitive RT or CRT, and survival outcomes were compared based on various factors, including BMI, CONUT score, CD8 expression, and HLA class II expression.

Results

We observed better overall survival (OS) rates in CD8-positive patients and those with higher HLA class II expression. The univariate analysis identified stage, p16 status, BMI, CONUT score, and CD8 expression as significantly associated with OS. In multivariate analysis, stage, BMI, and CONUT score remained significant predictors of OS. A risk scoring system was developed based on stage, p16 status, BMI, CONUT score, and CD8 expression. Patients were categorized into low-risk and high-risk groups, with significantly better survival in the low-risk group.

Conclusion

A combined risk score incorporating clinical, nutritional, and immune factors can improve the prediction of treatment outcomes for OPC patients. This risk stratification may enable personalized treatment plans and improve ΟS rates.

PD-L1 immunohistochemical expression considering HPV status in oropharyngeal squamous cell carcinoma

This systematic review aims to determine whether the presence of human papillomavirus (HPV) influences the immunohistochemical expression of programmed cell death-1 ligand (PD-L1) in oropharyngeal squamous cell carcinoma (OPSCC). PD-L1 immunohistochemical expression varies in OPSCC, and the presence of HPV is a plausible explanation for this variability. Comprehending these findings is crucial, as high PD-L1 expression in the tumor microenvironment of OPSCC can help identify patient subgroups that could be suitable for immunotherapy. Therefore, a systematic review was conducted following PRISMA guidelines (CRD42023437800). An electronic literature search was performed without time or language restrictions. The search included PubMed/MEDLINE, Embase, Scopus, Web of Science, https://clinictrials.gov, and relevant journals. A meta-analysis was performed using RStudio. Fourteen studies involving 1,629 participants were included. The sample consisted predominantly of males (81.26%) with a mean age of 58.3 years. Concerning clinical and pathological characteristics, the most frequently described anatomical location was the tonsils (68.54%), and most participants were either current or former smokers (78%) and alcohol users (79%). Advanced TNM IV was the most common stage. Regarding histopathological characteristics, HPV 16 was the only type mentioned, and half of the cases were detected through immunohistochemistry. The SP142 clone (35.7%) and the pattern of membrane immunostaining in tumor cells (71%) were the most commonly employed methods. The most prevalent findings were positive expression of PD-L1 (64.28%) and negative HPV status (57.14%). The association between PD-L1 positivity and HPV positivity (78.57%) was confirmed by meta-analysis. The conclusion was that HPV-positive status has an impact on immunohistochemical expression of PD-L1 in OPSCC.

Standardized Digital Image Analysis of PD-L1 Expression in Head and Neck Squamous Cell Carcinoma Reveals Intra- and Inter-Sample Heterogeneity with Therapeutic Implications

For practical reasons, in many studies PD-L1 expression is measured by combined positive score (CPS) from a single tumor sample. This does not reflect the heterogeneity of PD-L1 expression in head and neck squamous cell carcinoma (HNSCC). We investigated the extent and relevance of PD-L1 expression heterogeneity in HNSCC analyzing primary tumors and recurrences (LRs), as well as metastases. Tumor tissue from 200 HNSCC patients was immunohistochemically stained for PD-L1 and analyzed using image-analysis software QuPath v3.4 with multiple specimens per patient. CPS was ≥20 in 25.6% of primary tumors. Intra-tumoral heterogeneity led to a therapeutically relevant underestimation of PD-L1 expression in 28.7% of patients, when only one specimen per patient was analyzed. Inter-tumoral differences in PD-L1 expression between primary tumors and lymph node metastasis (LNM) or LR occurred in 44.4% and 61.5% (CPS) and in 40.6% and 50% of cases (TPS). Overall survival was increased in patients with CPS ≥ 1 vs. CPS < 1 in primary tumors and LNM (hazard ratio: 0.46 and 0.35; p < 0.005); CPS in LR was not prognostic. Our analysis shows clinically relevant intra- and inter-sample heterogeneity of PD-L1 expression in HNSCC. To account for heterogeneity and improve patient selection for immunotherapy, multiple sample analyses should be performed, particularly in patients with CPS/TPS < 1.

Meeting report: the 66th annual meeting of the Japanese Radiation Research Society in Tokyo, Japan, 6-8 November 2023

The 66th Annual Meeting of the Japanese Radiation Research Society took place in Tokyo, Japan, from 6 to 8 November 2023. The meeting covered a wide range of radiation research topics, including basic mechanisms involved in radiation effects, translational research, and epidemiology. Some sessions were jointly organized with the International Commission on Radiological Protection (ICRP). Here, we report on some plenary and keynote talks presented at the meeting.

High PD-L1 expression on immune cells along with increased density of tumor-infiltrating lymphocytes predicts a favorable survival outcome for patients with loco-regionally advanced head and neck cancer: early results from a prospective study

Introduction

In the era of personalized medicine and treatment optimization, use of immune biomarkers holds promise for estimating the prognosis of patients with head and neck squamous cell carcinoma (HNSCC) undergoing definitive treatment.

Methods

To evaluate the prognostic potential of immune biomarkers, we conducted a prospective monocentric cohort study with loco-regionally advanced HNSCC patients indicated for definitive radiotherapy/radiochemotherapy at the Department of Oncology, Ostrava University Hospital, Czech Republic, between June 2020 and August 2023. We focused on the expression of programmed death ligand 1 (PD-L1) and tumor-infiltrating lymphocytes (TILs) relative to overall survival (OS) and specific survival rates. Associations between biomarkers and survival rates were assessed by crude and adjusted hazard ratios (cHR, aHR, respectively) obtained from Cox proportional hazards regression.

Results

Among a total of 55 patients within a median follow-up of 19.7 months, there were 21 (38.2%) all-cause deaths and 15 (27.3%) cancer-related deaths. An overall survival (OS) rate of 61.8% and a disease-specific survival (DSS) rate of 72.7% were recorded. A significant association between survival rates and a ≥10% difference in PD-L1 expression on immune versus tumor cells (high PD-L1IC expression) was documented regardless of the type of analysis (univariate or multivariate). In addition, a stronger association was confirmed for OS and the composite biomarker high PD-L1IC expression along with either median-higher CD8+ TIL count or increased TIL density ≥30%, as indicated by an aHR of 0.08 (95% CI, 0.01 to 0.52) and 0.07 (95% CI, 0.01 to 0.46), respectively. Similar results were demonstrated for other specific survival rates.

Discussion

The early outcomes of the present study suggest the utility of a strong prognostic factor involving a composite biomarker high PD-L1IC expression along with increased TIL density in HNSCC patients undergoing definitive radiotherapy and radiochemotherapy.

Trial registration

The study is registered with Clinicaltrials.gov. - NCT05941676.

The role of radiotherapy in tumor immunity and the potential of PET/CT in detecting the expression of PD-1/PD-L1

Upregulation of PD-1/PD-L1 allows cancer cells to escape from host immune systems by functionally inactivating T-cell immune surveillance. Clinical blockade strategies have resulted in an increased prevalence of patients with late-stage cancers. However, many cancer patients had limited or no response to current immunotherapeutic strategies. Therefore, how to improve the sensitivity of immunotherapy has become the focus of attention of many scholars. Radiotherapy plays a role in the recruitment of T cells in the tumor microenvironment, increases CD4 + and CD8 + T cells, and increases PD-L1 expression, resulting in the synergistically enhanced antitumor effect of irradiation and PD-L1 blockade. Radiotherapy can cause changes in tumor metabolism, especially glucose metabolism. Tumor glycolysis and tumor immune evasion are interdependent, glycolytic activity enhances PD-L1 expression on tumor cells and thus promotes anti-PD-L1 immunotherapy response. Therefore, the mechanism of radiotherapy affecting tumor immunity may be partly through intervention of tumor glucose metabolism. Furthermore, some authors had found that the uptake of 2'-deoxy-2'-[18F]fluoro-D-glucose(18F-FDG) was correlated with PD-1/PD-L1 expression. Positron emission tomography/computed tomography (PET/CT) is a non-invasive detection method for PD-1/PD-L1 expression and has several potential advantages over immunohistochemical (IHC), PET/CT can dynamically reflect the expression of PD-1/PD-L1 inside the tumor and further guide clinical treatment.

Immunohistological evaluation of patients treated with intra-arterial chemoradiotherapy and surgery for oral cancer

Preoperative intra-arterial chemoradiotherapy (IACRT) can improve the outcome and reduce the extent of surgery in patients with advanced oral cancer. However, the response to this regimen varies among patients, which may be related to the immune status of the tumor. We investigated the effects of proteins involved in tumor immunity on the outcomes of combined IACRT and surgery for oral cancer. We examined CD8 + and FoxP3 + tumor-infiltrating lymphocytes (TILs) and programmed death ligand 1 (PD-L1) expression on immune cells and tumor cells in pretreatment biopsy samples from 69 patients diagnosed with oral cancer treated with IACRT at our institution during 2000-2020. Patients with abundant CD8 + TILs had significantly better 5-year disease-specific survival (DSS) compared to that of patients with less infiltration of these cells (P = 0.016). Patients with higher FoxP3 + T-cells invasion had significantly better DSS compared to that of less FoxP3 (P = 0.005). Patients with high PD-L1 expression in tumor cells and immune cells had significantly better DSS than that of patients with low PD-L1 expression in these cells (P = 0.009 and P = 0.025, respectively). Collectively, these results suggest that the tumor immune microenvironment could affect outcomes of IACRT treatment in oral cancer.

Prognostic value and clinicopathological status of PD-L1 expression and CD8+ TILs in oral squamous cell cancer patients with or without traditional risk factors

BACKGROUND

Non-smokers, non-drinkers, and non-betel quid chewers (NSNDNBs) with oral squamous cell carcinoma (OSCC) have poor survival outcomes. Tumor microenvironment based on PD-L1/CD8+ T cell infiltrated lymphocyte (TIL) proportion is proposed as a prognostic indicator.

METHODS

Immunohistochemistry staining was performed on OSCC samples from 64 patients. The PD-L1/CD8+ TILs were scored and stratified into four groups. Disease-free survival (DFS) was analyzed using a Cox regression model.

RESULTS

OSCC in NSNDNB patients was associated with female sex, T1-2 classification, and PD-L1 positivity. Low CD8+ TILs correlated with perineural invasion. High CD8+ TILs correlated with improved DFS. PD-L1 positivity was not correlated with DFS. Type IV tumor microenvironment yielded the highest DFS (85%).

CONCLUSION

NSNDNB status relates to PD-L1 expression regardless of CD8+ TILs infiltration. Type IV tumor microenvironment was associated with the best DFS. High CD8+ TILs resulted in better survival, while PD-L1 positivity alone was not correlated to DFS.

CD8+ T Cells and PD-L1 Expression as Prognostic Indicators in a Low Prevalence of HPV-Associated Oropharyngeal Squamous Cell Carcinoma

Human papillomavirus (HPV) infection detected in oropharyngeal squamous cell carcinoma (OPSCC) is associated with a better survival outcome from previous literature. However, Thailand and several Asian countries have a low prevalence of HPV-associated OPSCC and, therefore, have a low positive rate of immunostaining with p16. Tumor microenvironments (TME), including tumor-infiltrating CD8+ lymphocytes (CD8+ TIL) and programmed death ligand 1 (PD-L1), are proposed as significant prognostic indicators in addition to p16.

OBJECTIVES

Explore the expression p16, CD8+ TIL, and PD-L1 and its value as prognostic indicators for overall survival (OS) in patients with OPSCC.

MATERIALS AND METHODS

Data from patients with OPSCC diagnosed from 2012 to 2018 were recovered from medical records and national registry. All available glass slides and slides of immunohistochemistry (IHC) of p16, CD8, and PD-L1 were reviewed. The TME was classified into four types according to the expression pattern of PD-L1 and CD8+TIL. Overall survival (OS) was assessed using the Kaplan-Meier method and Cox regression model analysis.

RESULTS

In 160 OPSCC patients, p16 was positive in 27 (16.88%). The density of CD8+ TIL was higher in the p16+ and PD-L1+ groups (p = 0.005, 0.039); however, there was no association between p16 and the status of PD-L1. P16 and CD8+ TIL were significant prognostic factors for better OS (p = 0.007, 0.001), but not PD-L1 status (p = 0.317). Among the four types of TME, carcinoma showed mainly type IV TME (PD-L1-/TIL+), while OPSCCs with type I TME (PD-L1+/TIL+) had the best survival outcome.

CONCLUSIONS

The positivity of p16 and the density of CD8+ TIL were associated with better OS in OPSCC, while the status of PD-L1 was not significantly related to OS. OPSCC with type I TME (PD-L1+/TIL+) showed the best prognosis of all types of TME.

Canine oral squamous cell carcinoma as a spontaneous, translational model for radiation and immunology research

Introduction

Improving outcomes for oral squamous cell carcinoma (OSCC) patients has been hindered by a lack of effective predictive animal models. Spontaneously occurring canine OSCC could help fill this gap. The objective of this study was to characterize the immune landscape of canine OSCC to advance understanding of how dogs could serve as a surrogate for human OSCC.

Methods/Results

Canine OSCC contains a heterogenous tumor immune microenvironment. CD3+ T cells were the predominant tumor infiltrating immune cell population; however, there was a wide range CD3+ T cell density across samples. The most common CD3+ T cell micro-anatomical distribution was defined as "pre-existing immunity", but the remaining 20% of tumors were characterized as "immunologically ignorant" or "excluded infiltrates" patterns. When compared to normal oral mucosa, the tumor gene expression pattern suggests that canine OSCC microenvironment is highly inflamed and characterized by the presence of an anti-tumor immune response dominated by cytotoxic\effector T cells and NK cells (CD8a, GZMA, OX40, and HLA-A); however, overexpression of genes associated with effector T cell exhaustion and microenvironmental immunosuppression was also identified (PD-1, LAG3, CXCL2). Correlations between CD3+ T cell density and immune gene expression revealed key genes associated with cytotoxic anti-tumor T cell responses (GZMA, GZMB, PRF1), co-stimulation of T cells (CD27, CD28, ICOS), and other immune processes, including Type I IFN response (TNF, TNFSF10), and T cell exhaustion (CTLA4, PD-1). CD3+ T cell density in canine OSCC was significantly correlated with a cytolytic activity score (mean PRF1 and GZMA expression), suggestive of active effector CD8 T cell function. CD204+ macrophages were the second most abundant tumor infiltrating immune cell, and when comparing to normal oral mucosa, two differently expressed genes linked to tumor associated macrophages and myeloid derived suppressor cells (MDSC) were identified: CXCL2, CD70. Overexpression of CXCL2 was also identified in canine OSCC "T cell-high" tumors compared to "T cell-low" tumors.

Discussion

This study identified actionable immunotherapy targets which could inform future comparative oncology trials in canine OSCC: CTLA-4, PD-1, CXCL2. These data provide a good first step towards utilizing spontaneous canine OSCC as a comparative model for human OSCC radiation and immuno-oncology research.

Expression of PD-L1 is HPV/P16-independent in oral squamous cell carcinoma

Objectives

Study design

Results

Conclusion

Correlation between hematological parameters and PET/CT metabolic parameters in patients with head and neck cancer

Background

Systemic inflammation is predictive of the overall survival in cancer patients and is related to the density of immune cells in the tumor microenvironment of cancer, which in turn correlates with ¹⁸F -fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) metabolic parameters (MPs). The density of tumor-infiltrating lymphocytes (TILs) in the microenvironment has the potential to be a biomarker that can be used clinically to optimize patient selection in oropharyngeal head and neck squamous cell carcinoma (HNSCC). There is little to no data regarding the association of systemic inflammation with PET/CT-MPs, especially in HNSCC. This study aimed to evaluate the correlation between markers of host inflammation, namely blood neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR), with the PET/CT-MPs standardized uptake value (SUV), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the primary tumor, derived from FDG-PET/CT in patients with nonmetastatic (cM0) HNSCC before treatment. We hypothesized that NLR and PLR at baseline are positively correlated with PET/CT-MPs.

Methods

A retrospective review of consecutive patients with HNSCC with a pretreatment PET/CT was performed. NLR and PLR were computed using complete blood counts measured within 10 days before the start of any treatment. The correlation between NLR and PLR with PET/CT-MPs was evaluated with Spearman's rho test.

Results

Seventy-one patients were analyzed. Overall survival (OS) at 1, 2, and 3 years was 86%, 76%, and 68%. PLR was found to be correlated with MTV (rho = 0.26, P = .03) and TLG (rho = 0.28, P = .02) but not with maximum SUV or mean SUV. There was no correlation between NLR and the analyzed PET/CT-MPs. TLG was associated with worse survival in uni- and multivariable analysis, but no other PET/CT-MPs were associated with either OS or disease-specific survival (DSS). NLR and PLR were associated with OS and DSS on uni- and multivariable analysis.

Conclusions

In patients with HNSCC before any treatment such as definitive radio (chemo)therapy or oncologic surgery followed by adjuvant RT, baseline PLR correlated with MTV and TLG but not with SUV. NLR was not correlated with any PET/CT-MPs analyzed in our study. Confirmatory studies are needed, and a potential interaction between tumor microenvironment, host inflammation, and FDG-PET/CT measures warrants further investigation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13014-022-02112-4.

Radiotherapy for HPV-related cancers: prediction of therapeutic effects based on the mechanism of tumor immunity and the application of immunoradiotherapy

Human papillomavirus (HPV)-related cancer is one of the diseases entities for which the applications of radiotherapy have been increasing. Recently, the process of carcinogenesis from HPV infection and the mechanism of tumor immunity that develops during disease progression have been elucidated. In this review, we will describe the mechanism of tumor immunity and how chemoradiotherapy may overcome and improve the efficacy of tumor immunity. We will also discuss the usefulness of proteins involved with tumor immunity as a predictive marker of radiotherapy response, and present an overview of ongoing clinical trials of combinations of immune checkpoint inhibitors and radiotherapy to demonstrate the promising combination therapy that has been currently emerging.

Prognostic Significance of PD-L1 Expression In Patients With Primary Oropharyngeal Squamous Cell Carcinoma: A Meta-Analysis

Background

At present, the prognostic significance of programmed cell death receptor ligand 1 (PD-L1) expression in oropharyngeal squamous cell carcinoma (OPSCC) patients is still controversial. In this study, we aim to synthesize relevant studies that have assessed the prognostic value of PD-L1 in patients with primary OPSCC treated according to the current standard-of-care.

Methods

A systematic search of Medline/PubMed, Cochrane, Embase, Web of Science, and Scopus was conducted to define the prognostic role of PD-L1 expression in OPSCC. All studies published before July 31, 2021 were screened. Summary hazard ratios (sHR) with 95% confidence intervals (CIs) were calculated using a random-effects model.

Results

A total of 1522 OPSCC patients from 12 studies were included. PD-L1 expression in OPSCC tumor cells (TCs) was significantly associated with longer overall survival (sHR=0.63, 95% CI 0.50-0.79), and progression-free survival (sHR=0.62, 95% CI 0.49-0.79). A benefit in survival was also observed in PD-L1-positive OPSCC patients who underwent surgery (sHR=0.34, 95% CI 0.18-0.65). Finally, although PD-L1-positive expression was related to better outcomes both in HPV-negative and HPV-positive OPSCC, the difference reached the statistical significance only in the HPV-positive subgroup (sHR=0.37, 95% CI 0.19-0.73). No heterogeneity emerged between studies for all considered outcomes, with I² ranging from 0% for progression-free survival to 11% for overall survival.

Conclusions

PD-L1 expression on TCs associated with improved survival in OPSCC. In particular, HPV-positive OPSCC most benefited from PD-L1 expression when compared to the PD-L1 negative counterpart. Thus, PD-L1 might represent a useful biomarker to stratify prognosis in OPSCC in addition to HPV status.

Oropharyngeal Squamous Cell Carcinoma Treatment in the Era of Immune Checkpoint Inhibitors

While head and neck squamous cell carcinomas (HNSCC) are marginally decreasing due to the reduction in exposure to the major risk factors, tobacco and alcohol, the incidence of high-risk human papillomavirus (HPV)-positive oropharynx squamous cell carcinomas (OPSCC), especially those in the tonsil and base of tongue subsites, are increasing. Patients with the latter are younger, display a longer overall survival, and show a lower recurrence rate after standard-of-care treatment than those with HPV-negative OPSCC. This may reflect an important role for immune surveillance and control during the natural history of the virally driven tumour development. Immune deviation through acquisition of immune-suppressive factors in the tumour microenvironment (TME) is discussed in relation to treatment response. Understanding how the different immune factors are integrated in the TME battleground offers opportunities for identifying prognostic biomarkers as well as novel therapeutic strategies. OPSCC generally receive surgery or radiotherapy for early-stage tumour treatment, but many patients present with locoregionally advanced disease requiring multimodality therapies which can involve considerable complications. This review focuses on the utilization of newly emerged immune checkpoint inhibitors (PD-1/PD-L1 pathway) for treatment of HNSCC, in particular HPV-positive OPSCC, since they could be less toxic and more efficacious. PD-1/PD-L1 expression in the TME has been extensively investigated as a biomarker of patient response but is yet to provide a really effective means for stratification of treatment. Extensive testing of combinations of therapeutic approaches by types and sequencing will fuel the next evolution of treatment for OPSCC.

PD-L1 expression in anogenital and oropharyngeal squamous cell carcinomas associated with different clinicopathological features, HPV status and prognosis: a meta-analysis

Background: Little research has been done on clinicopathological characteristics and human papillomavirus (HPV) status of anogenital and oropharyngeal squamous cell carcinomas (SCC) with a strong expression of programmed death ligand 1 (PD-L1) in tumor cells. Therefore, we conducted this meta-analysis. Methods: We performed a comprehensive research in PubMed, Embase and Cochrane databases up to 30 September 2020. The effect size was hazard ratio (HR) with 95% confidence interval (CI) for overall survival (OS), cancer-specific survival (CSS), disease-free survival (DFS). The pooled odds ratio (OR) with 95% CI were used to assess the association between PD-L1 expression and clinicopathological features along with HPV status. Results: A total of 2003 cases (944 anogenital and 1059 oropharynx SCC patients) were included. High PD-L1 expression in anogenital SCC cases were associated with advanced age (OR = 1.63, 95% CI: 1.04–2.58) and HPV negativity (OR = 0.47, 95% CI: 0.31–0.71). Besides, PD-L1 positive anogenital SCC cases held a significantly declined OS (HR = 2.18, 95% CI: 1.37–3.47) and CSS (HR = 2.45, 95% CI: 1.30–4.65). For oropharynx SCC, PD-L1 was more frequent in younger and HPV positive patients (OR = 0.60, 95% CI: 0.37–0.98; OR = 3.01, 95% CI: 1.78–5.09) and PD-L1 expression was relevant to better OS and DFS (HR = 0.76, 95% CI: 0.60–0.97; HR = 0.50, 95% CI: 0.33–0.75). Conclusions: The meta-analysis demonstrated that in anogenital SCC, PD-L1 positivity had to do with a worse outcome, which might attribute to advanced age, higher tumor grade, lymph node metastasis and HPV negativity, while in oropharynx cancer, PD-L1 expression was related to better prognosis for the reason that PD-L1 was less frequent in the aged and negative HPV status.

The Tumor Microenvironment and Immunotherapy of Oropharyngeal Squamous Cell Carcinoma

Oropharyngeal squamous cell carcinoma (OPSCC) develops as a consequence of several mutations in the tumor suppressor pathways or after a progressive infection with high risk human papillomavirus (HPV). The dismal side effects of the current standard of care and the clear involvement of the immune system has led to a surge in clinical trials that aim to reinforce the tumor-specific immune response as a new treatment option. In this review, we have focused on the most recent literature to discuss the new findings and insights on the role of different immune cells in the context of OPSCC and its etiology. We then applied this knowledge to describe potential biomarkers and analyzed the rationale and outcomes of earlier and ongoing immunotherapy trials. Finally, we describe new developments that are still at the preclinical phase and provide an outlook on what the near future may bring, now that several new and exciting techniques to study the immune system at the single cell level are being exploited.

Association between cancer immunity and treatment results in uterine cervical cancer patients treated with radiotherapy

OBJECTIVE

To evaluate proteins related to tumor immune response and treatment outcome from radiotherapy for uterine cervical cancer patients.

METHODS

We performed a retrospective immunohistochemical staining of 81 patients with uterine cervical cancer who underwent definitive radiotherapy. We examined the expression of programmed death ligand 1, human leukocyte antigen class I, tumor-infiltrating CD8+, and forkhead box P3+ (FoxP3+) T cells in tumor tissues.

RESULTS

In biopsy specimen, patients with a higher number of CD8+ T cells and FoxP3+ T cells had a better disease-specific survival than patients with a lower number of CD8+ T cells and FoxP3+ cells (P = 0.018 and P = 0.009). Multivariate analysis showed that equivalent dose in 2 Gy fractions (EQD2) of the minimum dose to 90% of the high-risk clinical target volume, FoxP3+ T cells and expression of human leukocyte antigen class I were significant prognostic factors. When the EQD2 is 70 Gy or more, a higher local control rate is obtained regardless of the number of CD8- or FoxP3-positive cells. When EQD2 is <70 Gy, the number of CD8-positive cells has a significant impact on treatment outcome: the recurrence rate (local recurrence rate + distant metastasis rate) was 46.2% in the group with a CD8 value of 230 or higher, whereas the recurrence rate was 75.7% in the group with a CD8 value of less than 230.

CONCLUSION

The combination of CD8 or FoxP3 with EQD2 can be potentially useful to predict the treatment results of radiotherapy for cervical cancer, leading to individualized optimal selection of treatment for cervical cancer.

Role of GLUT-1 in the Upregulation of PD-L1 Expression After Radiotherapy and Association of PD-L1 with Favourable Overall Survival in Hypopharyngeal Cancer

Purpose

The alteration of tumor immunity after radiotherapy (RT) has been widely studied in recent years. However, the mechanism through which RT mediates tumor immunity and the involvement of glycolysis in this mediation in hypopharyngeal cancer remain unclear. This study investigated whether RT regulates programmed cell death ligand 1(PD-L1) partly via glucose transporter 1(GLUT-1) expression and whether PD-L1 expression predicts overall survival (OS) in patients with hypopharyngeal cancer.

Methods

The expression of PD-L1 and Glut-1, and the numbers of CD4+, CD8+ T cells were detected by immunohistochemical analysis on 47 pre-RT and 25 post-RT specimens of hypopharyngeal cancer. Changes in these indicators before and after RT were compared, and their association with the OS of patients was analyzed. Moreover, we used siRNA-GLUT-1 to inhibit GLUT-1 expression and examined whether GLUT-1 was a key factor involved in the mediation of PD-L1 expression by RT in vitro.

Results

In the multivariate analysis, patients with higher PD-L1 expression (p=0.037), higher CD4+ T cell infiltration (p=0.016) and earlier clinical stage (p=0.019) had favourable OS. The expression of PD-L1, and the CD4+ and CD8+ T cells was markedly increased following RT. PD-L1 expression was correlated with Glut-1 pre-RT (p=0.002), but not after RT (p=0.051). The expression of PD-L1 in FaDu cells was upregulated after RT, especially at 96h after RT in vitro. However, the expression of PD-L1 in siRNA-GLUT-1 FaDu cells was markedly decreased at 96h after RT compared with that measured in FaDu cells.

Conclusion

Patients with high PD-L1 expression and CD4+ T cell infiltration may have favourable OS in hypopharyngeal cancer. RT may increase PD-L1 expression and alter tumor immunity. The expression of PD-L1 was correlated with Glut-1, and inhibition of GLUT-1 expression may decrease the expression of PD-L1. GLUT-1 may participate in the alteration of tumor immunity after RT.

Immune checkpoint expression in HNSCC patients before and after definitive chemoradiotherapy

BACKGROUND

Primary platinum-based chemoradiotherapy (CRT) remains the treatment of choice for nonresectable squamous cell carcinoma of the head and neck (HNSCC). Immune-checkpoint modulators are used as palliative therapy and studied in combination with definitive CRT. However, the immunological changes by CRT need yet to be understood.

METHODS

A cohort consisting of 67 paired tissue biopsies (N = 134) of HNSCC patients before and after CRT was created. The expression of PD-1, PD-L1, and CD27 of tumor and immune cells by immunohistochemistry was evaluated.

RESULTS

PD-L1 expression on immune cells of non-responders was significantly lower before CRT (P = .008). CD27 was expressed only on immune cells and not on cancer cells. A significant lower CD27-expression score was observed following CRT (P = .019).

CONCLUSIONS

Conventional CRT changes the expression of CD27 in the tumor microenvironment. Whether this is due to a loss of expression or a reduction of CD27+ cells must be evaluated in further analyses.

The tumor immune microenvironment and its implications for clinical outcome in patients with oropharyngeal squamous cell carcinoma

BACKGROUND

We examined PD-L1 expression on tumor cells (TCs) and immune cells (ICs) and density of CD3⁺ and CD8⁺ tumor-infiltrating lymphocytes (TILs) in patients with oropharyngeal squamous cell carcinoma (OPSCC) and investigated their significance on clinicopathological characteristics and clinical outcomes.

METHODS

In a cohort of 65 patients treated by definitive intensity-modulated radiotherapy (IMRT) with curative intent, immunohistochemical analysis of PD-L1 expression on TCs and ICs, and TIL subtyping was performed on primary biopsy tumor tissues, followed by prognostic evaluation of these immune response-related parameters including classification into four tumor immune microenvironment (TIM) types. To evaluate HPV status, p16 immunohistochemistry was performed.

RESULTS

Densities of CD3⁺ and CD8⁺ TILs and PD-L1 expressions on TCs and ICs were significantly higher in p16+/HPV-mediated OPSCC. Patients with high densities of stromal CD8⁺ TILs displayed significantly better overall survival (OS) and progression-free survival (PFS). PD-L1 expression neither on tumor cells nor on immune cells affected survival outcomes. Distribution of TIM types based on the combination of PD-L1 expression on TCs and densities of CD8⁺ TILs is significantly different in p16+ compared with p16- OPSCC. In type III TIM (TC-PD-L1+/low CD8⁺ TIL density), significantly better OS was shown in p16+ group compared with p16- OPSCC.

CONCLUSION

The prognostic and predictive role of tumor immune microenvironment was confirmed for patients with OPSCC. Combining HPV status with the evaluation of densities of CD8⁺ TILs and PD-L1 expression including TIM classification might be of high clinical interest and warrants further prospective evaluation.

Concordance of tumor infiltrating lymphocytes, PD-L1 and p16 expression in small biopsies, resection and lymph node metastases of oropharyngeal squamous cell carcinoma

OBJECTIVE

The incidence of oropharyngeal squamous cell carcinoma (OPSCC), especially human papillomavirus (HPV)-associated, is increasing worldwide. Immunotherapy become available for patients with carcinomas in the head and neck region, however without ideal biomarker. Markers like PD-L1 vary in the clone of the antibody used, and the method of evaluation. Adequate and reliable immune cells characterization and evaluation is still not found. Furthermore, studies analyzing representativeness of different tissue samples are scarce. We analyzed small biopsy, lymph node (LN) metastasis and resected OPSCC, in regards of tumor infiltrating lymphocyte (TIL) density, PD-L1 and p16 expression.

MATERIAL AND METHODS

Patients with OPSCC diagnosed from 2000 to 2016, with small biopsy, resection specimen and LN metastasis samples were selected. We analyzed TILs on hematoxylin-eosin stain, and PD-L1 and p16 expression in tumor cells. Concordance between different tumor locations was evaluated.

RESULTS

93 patients, with 65 small biopsies, 72 resection specimens, and 70 LN metastases were included. TILs, p16 and PD-L1 demonstrated very high concordance. Additionally, PD-L1 expression in the small biopsies was more representative of the PD-L1 expression in the resection specimens, than the LN samples.

CONCLUSION

TILs density can be reliably assessed using hematoxylin-eosin stain with high concordance between the small biopsy, resection specimen and LN metastasis. Evaluation of concordance of p16 expression is very high, nevertheless some cases might be misdiagnosed on a small biopsy or lymph node metastasis. Evaluation of PD-L1 expression is very reliable on the biopsy specimen. Different PD-L1 clones and methods of evaluation still remain to be addressed.

Prognostic impact of PD-L1 in oropharyngeal cancer after primary curative radiotherapy and relation to HPV and tobacco smoking

Background: Incidence of oropharyngeal squamous cell carcinoma (OPSCC) is rising rapidly in many western countries due to Human papillomavirus (HPV) and tobacco smoking, with a considerable overlap. Immunotherapy directed at the PD1/PD-L1 axis have shown promise in head and neck cancer and other cancer types. PD-L1 expression may indicate a poorer prognosis, and at the same time indicate a possible benefit of anti-PD-L1 immunotherapeutic agents. The primary aim of this study was to establish the prognostic effect of PD-L1 expression after primary curative radiotherapy alone.Material and methods: A cohort of 303 OPSCC patients treated with primary, curative intended radiotherapy was established. PD-L1 expression was evaluated by immunohistochemistry on formalin fixed, paraffin embedded tissue sections. PD-L1 positivity was defined as a Combined Positive Score (CPS) ≥1, indicating staining of either tumor cells, lymphocytes or macrophages.Results: Median follow-up was 5.3 years. With 199 deaths, there was no difference in overall survival between patients with PD-L1+ and PD-L1- tumors (adjusted hazard ratio [aHR] and 95% confidence interval [CI]: 1.0 [0.71-1.4]). Also, locoregional failure was similar between the two groups (aHR 1.1 [CI: 0.68 - 1.7]). Tumors were PD-L1+ in 76% of cases, significantly more among HPV p16+ tumors (82% vs. 70%, p = .01). Interestingly, higher prevalence of PD-L1+ expression was seen in HPV p16+ patients with <10 pack-years of tobacco-smoking (93%) compared to HPV p16+ smokers (76%) or HPV p16-negative patients (70%) (p = .003).Conclusion: PD-L1 expression had no prognostic significance in OPSCC patients treated with primary radiotherapy alone. A substantial proportion of OPSCC tumors show PD-L1 overexpression, especially in HPV p16+ tumors in patients with little or no smoking history.

Association between radiotherapy-induced alteration of programmed death ligand 1 and survival in patients with uterine cervical cancer undergoing preoperative radiotherapy

PURPOSE

To evaluate radiotherapy-induced changes in the expression of programmed death ligand 1 (PD-L1), programmed death 1 (PD-1), and human leukocyte antigen class I (HLA-1) in patients with uterine cervical cancer, as well as infiltration of CD8+ and Forkhead box P3+ (FoxP3+) T lymphocytes into tumor tissue and the prognostic value of these parameters.

MATERIALS AND METHODS

We performed immunohistochemical analysis of pre-radiotherapy biopsies and corresponding post-radiotherapy resected tissues in 104 uterine cervical cancer patients undergoing preoperative chemoradiotherapy or radiotherapy alone. We scored the expression of various proteins to distinguish positive from negative samples.

RESULTS

PD-L1-expressing tumor cells (PD-L1 TC) increased significantly after chemoradiotherapy (p = 0.043). CD8+ T cell infiltration (p = 0.002) and FoxP3+ T cell infiltration (p = 0.003) decreased significantly after chemoradiotherapy. Expression of PD‑1, PD-L1-expressing immune cells (PD-L1 IC), and HLA‑1 did not change after chemoradiotherapy. In biopsy specimens obtained before chemoradiotherapy or radiotherapy, greater infiltration of CD8+ T cells (p = 0.001) and FoxP3+ T cells (p = 0.003) were significant predictors of better overall survival (OS). In surgical specimens obtained after chemoradiotherapy or radiotherapy, greater infiltration of PD-L1 TC was the only significant predictor of better OS (p < 0.001) and was related to a significantly lower probability of out-of-field recurrence (p = 0.005).

CONCLUSION

Chemoradiotherapy induced an immunologic shift that increased PD-L1 TC. Chemoradiotherapy has immunological effects that can influence the results of treatment for uterine cervical cancer.

Assessing the interactions between radiotherapy and antitumour immunity

Immunotherapy, specifically the introduction of immune checkpoint inhibitors, has transformed the treatment of cancer, enabling long-term tumour control even in individuals with advanced-stage disease. Unfortunately, only a small subset of patients show a response to currently available immunotherapies. Despite a growing consensus that combining immune checkpoint inhibitors with radiotherapy can increase response rates, this approach might be limited by the development of persistent radiation-induced immunosuppression. The ultimate goal of combining immunotherapy with radiotherapy is to induce a shift from an ineffective, pre-existing immune response to a long-lasting, therapy-induced immune response at all sites of disease. To achieve this goal and enable the adaptation and monitoring of individualized treatment approaches, assessment of the dynamic changes in the immune system at the patient level is essential. In this Review, we summarize the available clinical data, including forthcoming methods to assess the immune response to radiotherapy at the patient level, ranging from serum biomarkers to imaging techniques that enable investigation of immune cell dynamics in patients. Furthermore, we discuss modelling approaches that have been developed to predict the interaction of immunotherapy with radiotherapy, and highlight how they could be combined with biomarkers of antitumour immunity to optimize radiotherapy regimens and maximize their synergy with immunotherapy.

Prognostic impact of p16 and PD-L1 expression in patients with oropharyngeal squamous cell carcinoma receiving a definitive treatment

Aims

Limited information is available regarding the precise differences in the tumour immune microenvironment (TIM) of patients with human papilloma virus (HPV)-associated and non-HPV-associated oropharyngeal squamous cell carcinoma (OPSCC). Here, we retrospectively reviewed 137 patients with OPSCC treated with a definitive treatment to identify molecular relationships in the TIM.

Materials and methods

We used immunohistochemical analysis to assess p16 status, programmed death ligand 1 (PD-L1) level, and/or CD8⁺ tumour-infiltrating lymphocyte (TIL) density, followed by prognostic evaluation of these immune-related parameters.

Results

Multivariate analyses demonstrated that PD-L1 level on immune cells but not on tumour cells or CD8⁺ TIL density was a significant predictive factor of disease-free survival (DFS) and overall survival (OS). Additionally, subgroup analyses demonstrated that patients positive for p16 and PD-L1 expression on immune cells had favourable DFS and OS, whereas patients negative for p16 and PD-L1 expression on immune cells showed worse DFS and OS.

Conclusions

We demonstrated that PD-L1 expression on immune cells but not tumour cells might represent a useful prognostic biomarker in patients with OPSCC receiving a definitive treatment. We propose that a co-assessment of p16 and PD-L1 expression on immune cells would have greater prognostic potential compared with evaluation of each factor alone in patients with OPSCC.

Clinical relevance and significance of programmed death-ligand 1 expression, tumor-infiltrating lymphocytes, and p16 status in sinonasal squamous cell carcinoma

Purpose: Immunotherapy may be a potential alternative for patients with sinonasal squamous cell carcinoma (SNSCC). Data regarding potential immunotherapy targets, such as programmed death-ligand 1 (PD-L1) and tumor-infiltrating lymphocytes (TILs), in SNSCC are limited. In this study, we assessed the prevalence and prognostic value of PD-L1 expression and TILs in p16-negative and p16-positive SNSCC. Patients and methods: Tissues from 96 patients with SNSCC were stained using immunohistochemistry against PD-L1, CD8, and Foxp3 to assess the immune environment. The correlations between PD-L1 expression, TILs, and p16 status were analyzed. Additionally, PD-L1, CD8, and Foxp3 expressions, as well as p16 status, were analyzed in relation to patient clinicopathological variables and prognosis. Results: Twenty-nine (30.2%) patients with SNSCC showed PD-L1 expression in >5% of tumor cells. PD-L1 expression was significantly correlated with poor differentiation and a high level of TILs. PD-L1 expression and the CD8+ and Foxp3+ T-cell infiltrates in p16-negative patients (n=78, 81.2%) and p16-positive patients (n=18, 18.8%) were not significantly different. PD-L1 expression and p16 status were not associated with overall survival (OS) and disease-free survival (DFS). Patients with high CD8+ or Foxp3+ cell infiltration had better clinical outcomes. A multivariate analysis confirmed that CD8 TILs were a significant independent and favorable prognostic factor for OS (p=0.023) and DFS (p=0.008). Conclusion: TILs can play a prognostic role in SNSCC. We did not find differences in immune marker expression between p16-positive and p16-negative SNSCC tissues. The high correlation between PD-L1 expression and TILs indicates that the PD-1/PD-L1 pathway is a promising immunotherapeutic target for SNSCC.