Prognostic significance of tumor-infiltrating immune cells and PD-L1 expression in esophageal squamous cell carcinoma

Correlation of PD-L1 expression with CD8+ T cells and oxidative stress-related molecules NRF2 and NQO1 in esophageal squamous cell carcinoma

Oxidative stress and the immune microenvironment both contribute to the pathogenesis of esophageal squamous cell carcinoma (ESCC). However, their interrelationships remain poorly understood. We aimed to examine the status of key molecules involved in oxidative stress and the immune microenvironment, as well as their relationships with each other and with clinicopathological features and prognosis in ESCC. The expression of programmed death-ligand 1 (PD-L1), CD8, nuclear factor erythroid-2 related factor-2 (NRF2), and NAD(P)H quinone oxidoreductase 1 (NQO1) was detected using immunohistochemistry in tissue samples from 176 patients with ESCC. We employed both combined positive score (CPS) and tumor proportion score (TPS) to evaluate PD-L1 expression and found a positive correlation between CPS and TPS. Notably, PD-L1 expression, as assessed by either CPS or TPS, was positively correlated with both NRF2 nuclear score and NQO1 score in stage II-IV ESCC. We also observed a positive correlation between the density of CD8+ T cells and PD-L1 expression. Furthermore, high levels of PD-L1 CPS, but not TPS, were associated with advanced TNM stage and lymph node metastases. Moreover, both PD-L1 CPS and the nuclear expression of NRF2 were found to be predictive of shorter overall survival in stage II-IV ESCC. By using the Mandard-tumor regression grading (TRG) system to evaluate the pathological response of tumors to neoadjuvant chemotherapy (NACT), we found that the TRG-5 group had higher NRF2 nuclear score, PD-L1 CPS, and TPS in pre-NACT biopsy samples compared with the TRG-3 + 4 group. The NQO1 scores of post-NACT surgical specimens were significantly higher in the TRG-5 group than in the TRG 3 + 4 group. In conclusion, the expression of PD-L1 is associated with aberrant NRF2 signaling pathway, advanced TNM stage, lymph node metastases, and unfavorable prognosis. The dysregulation of PD-L1 and aberrant activation of the NRF2 signaling pathway are implicated in resistance to NACT. Our findings shed light on the complex interrelationships between oxidative stress and the immune microenvironment in ESCC, which may have implications for personalized therapies and improved patient outcomes.

LEAP-014: first-line lenvatinib + pembrolizumab + chemotherapy in advanced/metastatic esophageal squamous cell carcinoma

Treatment options for patients with advanced or metastatic esophageal squamous cell carcinoma (ESCC) are improving. Current guidelines recommend first-line pembrolizumab plus chemotherapy for patients with unresectable or metastatic ESCC, which has led to improvements in survival outcomes. Antiangiogenic therapy combined with immune checkpoint inhibitors can act synergistically to convert the immunosuppressive tumor microenvironment to an immune supportive microenvironment, thus enhancing antitumor immune responses. In preclinical models, the antiangiogenic agent lenvatinib combined with an anti-PD-1 agent showed synergistic antitumor activity. We describe the design and rationale for the randomized, open-label, phase III LEAP-014 study of lenvatinib in combination with pembrolizumab plus chemotherapy in patients with advanced or metastatic ESCC. Overall survival and progression-free survival are the dual primary end points.Clinical Trial Registration: NCT04949256 (ClinicalTrials.gov).

Prognostic significance of programmed cell death-ligand 1 expression on immune cells and epithelial-mesenchymal transition expression in patients with hepatocellular carcinoma

Purpose

Immune checkpoint inhibitors (ICIs) have been shown significant oncological improvements in several cancers. However, ICIs are still in their infancy in hepatocellular carcinoma (HCC). Programmed cell death-ligand 1 (PD-L1), tumor-infiltrating lymphocytes (TILs), and epithelial-mesenchymal transition (EMT) have been known as prognostic factors in HCC. Therefore, we have focused on identifying the molecular mechanisms between each marker to evaluate a predictive role.

Methods

Formalin-fixed paraffin-embedded samples were obtained from 166 patients with HCC who underwent surgery. The expression of PD-L1 and TILs and EMT marker were evaluated by immunohistochemical analysis.

Results

The multivariate analysis showed that TIL expression (hazard ratio [HR], 0.483; 95% confidence interval [CI], 0.269-0.866; P = 0.015) were independent prognostic factors for overall survival. The prognostic factors for disease-free survival were EMT marker expression (HR, 1.565; 95% CI, 1.019-2.403; P = 0.005). Patients with high expression of TILs had significantly better survival compared to patients with low expression (P = 0.023). Patients who were TIL+/EMT- showed a significantly better prognosis than those who were TIL-/EMT+ (P = 0.049).

Conclusion

This study demonstrates that PD-L1 expression of TILs is closely associated with EMT marker expression in HCC. Clinical investigations using anti-PD-1/PD-L1 inhibitors in patients with EMT-associated PD-L1 upregulation are warranted.

Intracellular Fusobacterium nucleatum infection attenuates antitumor immunity in esophageal squamous cell carcinoma

Currently, the influence of the tumor microbiome on the effectiveness of immunotherapy remains largely unknown. Intratumoural Fusobacterium nucleatum (Fn) functions as an oncogenic bacterium and can promote tumor progression in esophageal squamous cell carcinoma (ESCC). Our previous study revealed that Fn is a facultative intracellular bacterium and that its virulence factor Fn-Dps facilitates the intracellular survival of Fn. In this study, we find that Fn DNA is enriched in the nonresponder (NR) group among ESCC patients receiving PD-1 inhibitor and that the serum antibody level of Fn is significantly higher in the NR group than in the responder (R) group. In addition, Fn infection has an opposite impact on the efficacy of αPD-L1 treatment in animals. Mechanistically, we confirm that Fn can inhibit the proliferation and cytokine secretion of T cells and that Fn-Dps binds to the PD-L1 gene promoter activating transcription factor-3 (ATF3) to transcriptionally upregulate PD-L1 expression. Our results suggest that it may be an important therapeutic strategy to eradicate intratumoral Fn infection before initiating ESCC immunotherapies.

Tumor budding and tumor-infiltrating lymphocytes can predict prognosis in pT1b esophageal squamous cell carcinoma

BACKGROUND

Tumor budding (TB) and tumor-infiltrating lymphocyte (TIL) are significant predictive indicators of lymph node metastasis (LNM) and unfavorable prognosis in various tumors. Currently, there is no gold standard for TB and TIL evaluation in esophageal squamous cell carcinoma (ESCC). This study aimed to identify the standard of TB and TIL evaluations and build a predictive model for prognosis among patients with pT1b ESCC.

METHODS

We retrospectively analyzed the prognostic values of TB and TIL in 150 pT1b ESCC cases. Hematoxylin and eosin (H&E) and immunohistochemistry (IHC) of anti-pan cytokeratin (AE1/AE3) were used to analyze the threshold of TB, and intratumoral TIL and peritumoral TIL (pTIL) were evaluated using the receiver operating characteristic curves (ROC).

RESULTS

We found that TB in a three-tiered grading system (low-TB: 0-4; middle-TB: 5-15; high-TB: ≥16) displayed an excellent prognosis prediction for LNM and survival based on IHC staining using a 20× objective lens. Low pTIL level (≤20%) was a significant indicator of LNM and unfavorable prognosis (p < 0.05). Moreover, lower tumor location and lymphovascular invasion (LVI) were correlated with an unfavorable prognosis (p < 0.05). A nomogram developed based on TB, pTIL, LVI, and tumor location showed good discrimination, as shown by the area under the ROC and calibration curves.

CONCLUSION

We therefore recommend identifying TB using a 20× objective lens under IHC staining and TIL adjacent to the tumor. Additionally, a nomogram was built for facilitating individualized prediction of survival for patients with pT1b ESCC.

The role of interferon-gamma and its receptors in gastrointestinal cancers

Gastrointestinal malignancies are the most prevalent type of cancer around the world. Even though numerous studies have evaluated gastrointestinal malignancies, the actual underlying mechanism is still unknown. These tumors have a poor prognosis and are frequently discovered at an advanced stage. Globally, there is an increase in the incidence and mortality of gastrointestinal malignancies, including those of the stomach, esophagus, colon, liver, and pancreas. Growth factors and cytokines are signaling molecules that are part of the tumor microenvironment and play a significant role in the development and spread of malignancies. IFN-γ induce its effects by activation of intracellular molecular networks. The main pathway involved in IFN-γ signaling is the JAK/STAT pathway, which regulates the transcription of hundreds of genes and mediates various biological responses. IFN-γ receptor is composed of two IFN-γR1 chains and two IFN-γR2 chains. Binding to IFN-γ, causes the intracellular domains of IFN-γR2 to oligomerize and transphosphorylate with IFN-γR1 which activates downstream signaling components: JAK1 and JAK2. These activated JAKs phosphorylate the receptor, creating binding sites for STAT1. STAT1 is then phosphorylated by JAK, resulting in the formation of STAT1 homodimers (gamma activated factors or GAFs) that translocate to the nucleus and regulate gene expression. The balance between positive and negative regulation of this pathway is crucial for immune responses and tumorigenesis. In this paper, we evaluate the dynamic roles of IFN- γ and its receptors in gastrointestinal cancers and present evidence that inhibiting IFN- γ signaling may be an effective treatment strategy.

Neoadjuvant camrelizumab plus chemotherapy in locally advanced oesophageal squamous cell carcinoma: a retrospective cohort study

BACKGROUND

Neoadjuvant therapy is recommended to improve the prognosis of oesophageal squamous cell carcinoma (ESCC). As a PD-1 inhibitor developed in China, camrelizumab is more accessible and available for Chinese ESCC patients. Camrelizumab plus neoadjuvant chemotherapy has shown promising efficacy with acceptable toxicity for resectable ESCC in the NIC-ESCC2019 trial. However, this was a single-arm trial, so we conducted a retrospective cohort study to compare neoadjuvant camrelizumab plus chemotherapy with neoadjuvant chemotherapy alone in terms of the safety and efficacy in patients with locally advanced ESCC.

METHODS

Between January 2017 and December 2021, patients with stage II-IVa ESCC who received neoadjuvant therapy at the First Affiliated Hospital of Chongqing Medical University and underwent radical oesophagectomy were enrolled in our study. These included 19 patients who received neoadjuvant chemotherapy plus camrelizumab (group 1) and 40 patients who only received neoadjuvant chemotherapy (group 2).

RESULTS

The baseline characteristics of the patients were comparable between the two groups. The pathological complete response (pCR) rate in group 1 was significantly higher than that in group 2 (26.3% vs. 2.5%, P = 0.018). All patients in group 1 achieved complete resection (R0), compared with 39 (97.5%) patients in group 2. Adverse events occurred in 16 (84%) patients in group 1 versus 35 (87.5%) patients in group 2. No grade ≥ 4 adverse events occurred in either group. No significant difference was found in surgical outcomes or postoperative complications. The 90-day mortality rate was comparable between the two groups (1 patient died in group 1 versus 2 patients in group 2).

CONCLUSIONS

Neoadjuvant camrelizumab plus chemotherapy followed by surgery was associated with a promising pCR rate and a manageable safety profile for patients with locally advanced ESCC.

Intratumour Fusobacterium nucleatum and immune response to oesophageal cancer

BACKGROUND

Experimental evidence suggests a role of intratumour Fusobacterium nucleatum in the aggressive behaviour of gastrointestinal cancer through downregulating anti-tumour immunity. We investigated the relationship between intratumour F. nucleatum and immune response to oesophageal cancer.

METHODS

Utilising an unbiased database of 300 resected oesophageal cancers, we measured F. nucleatum DNA in tumour tissue using a quantitative polymerase chain reaction assay, and evaluated the relationship between the abundance of F. nucleatum and the densities of T cells (CD8 + , FOXP3 + and PDCD1 + ), as well as lymphocytic reaction patterns (follicle lymphocytic reaction, peritumoural lymphocytic reaction, stromal lymphocytic reaction and tumour-infiltrating lymphocytes) in oesophageal carcinoma tissue.

RESULTS

F. nucleatum was significantly and inversely associated only with the peritumoural lymphocytic reaction (P = 0.0002). Compared with the F. nucleatum-absent group, the F. nucleatum-high group showed a much lower level of the peritumoural lymphocytic reaction (univariable odds ratio, 0.33; 95% confidence interval, 0.16-0.65; P = 0.0004). A multivariable model yielded a similar finding (multivariable odds ratio, 0.34; 95% confidence interval 0.16-0.69; P = 0.002).

CONCLUSIONS

Intratumour F. nucleatum is associated with a diminished peritumoural lymphocytic reaction, providing a platform for further investigations on the potential interactive roles between intratumour F. nucleatum and host immunity.

Clinicopathological features of PD-L1 protein expression, EBV positivity, and MSI status in patients with advanced gastric and esophagogastric junction adenocarcinoma in Japan

This real-world study examined the prevalence of programmed death ligand-1 (PD-L1) expression and assessed the frequency of microsatellite instability-high (MSI-H) status and Epstein-Barr virus (EBV) positivity in Japanese patients with advanced gastric and gastroesophageal junction (GEJ) adenocarcinoma. This multicenter (5 sites), retrospective, observational study (November 2018–March 2019) evaluated Japanese patients with advanced gastric and GEJ adenocarcinoma after surgical resection (Stage II/III at initial diagnosis) or unresectable advanced cancer (Stage IV). The primary objectives were prevalence of PD-L1 expression (combined positive score [CPS] ≥1), MSI status, and EBV positivity. Tumor specimens of 389/391 patients were analyzed (male, 67.1%; mean age, 67.6 ± 12.2 years); 241/389 (62%) were PD-L1 positive, 24/379 (6.3%) had MSI-H tumors, and 13/389 (3.3%) were EBV positive. PD-L1 expression was higher in tumor-infiltrating immune cells than in tumor cells for lower CPS cutoffs. Among patients with MSI-H tumors and EBV-positive tumors, 19/24 (79.2%) and 9/13 (69.2%), respectively, were PD-L1 positive. A greater proportion of patients with MSI-H tumors (83.3% [20/24]) were PD-L1 positive than those with MSI-low/stable tumors (60.8% [216/355]; p = .0297); similarly, an association was observed between history of H pylori infection and PD-L1 expression. A higher proportion of patients with MSI-H tumors demonstrated PD-L1 expression with a CPS ≥10 (66.7% [16/24]) vs those with MSI-low/stable tumors (24.8% [88/355]; p < .0001). The prevalence of PD-L1 positivity among Japanese patients was comparable to that in previous pembrolizumab clinical trials and studies in gastric cancer. Particularly, higher PD-L1 expression was observed in MSI-H tumors.

Response to neoadjuvant immune checkpoint inhibitors and chemotherapy in Chinese patients with esophageal squamous cell carcinoma: the role of tumor immune microenvironment

BACKGROUND

Immune checkpoint inhibitors (ICIs) through programmed cell death 1 blockade improve the survival outcomes of patients with advanced esophageal squamous cell carcinoma (ESCC). Recently, the use of neoadjuvant immunotherapy for the treatment of ESCC has been gradually increasing. We aimed to evaluate the efficacy of neoadjuvant treatment of ICIs with chemotherapy and explore tumor microenvironment (TME) immune profiles of ESCC samples during neoadjuvant therapy.

METHODS

Patients with previously untreated, resectable, locally advanced ESCC (stage II or III) in Harbin Medical University Cancer Hospital were enrolled. Each patient received two to four cycles of neoadjuvant ICIs combined with chemotherapy before surgical resection. The TME immune profiles of formalin-fixed paraffin-embedded tumor samples at baseline and after surgery were evaluated by multiplex staining and multispectral imaging.

RESULTS

In all, 18 patients were enrolled, and all patients received surgery with R0 resection. The postoperative pathological evaluation indicated that 7 (38.9%) patients had a pathological complete response (pCR) and 11 (61.1%) patients had a partial response. The neoadjuvant therapeutic regimens had acceptable side effect profiles. The TME immune profiles at baseline observed higher densities of stroma CD3 + , PD-1 + , and PD-1 + CD3 + cells in pCR patients than in non-pCR patients. Comparing TME immune profiles before and after neoadjuvant treatment, an increase in CD8 + T cells and a decrease in CD163 + CD68 + M2-like macrophage cells were observed after neoadjuvant treatment.

CONCLUSIONS

Neoadjuvant ICIs combined with chemotherapy produced a satisfactory treatment response, demonstrating its anti-tumor efficacy in locally advanced ESCC. Further large-scale studies are required to understand the role of tumor immunities and ICIs underlying ESCC.

Research trends on anti-PD-1/PD-L1 immunotherapy for esophageal cancer: A bibliometric analysis

Objectives

The study aims to summarize publication characteristics of anti-programmed cell death protein 1 (PD-1)/programmed cell death 1 ligand 1 (PD-L1) immunotherapy for esophageal cancer and create scientific maps to explore hotspots and emerging trends with bibliometric methods.

Methods

The publications between 2012 and 2021 were retrieved from the Web of Science Core Collection (WoSCC) on June 20, 2022. Bibliometric tools including HistCite, VOSviewer, and CiteSpace were used for statistical analysis. Data on the trend of the annual output, countries/regions, institutions, journals, authors, subject categories, keywords, and co-cited references were presented in this study.

Results

A total of 552 publications written by 3,623 authors of 872 institutions, 44 countries/regions in 250 journals were included in the bibliometric study. China, USA and Japan were the key countries in this field. Kato Ken, Bang Yung-Jue, Frontiers in Oncology, Journal of Clinical Oncology and Natl Canc Ctr were the top 1 productive author, co-cited author, productive journal, co-cited journal and prolific institution, respectively. The top 4 most present keywords were esophageal cancer, immunotherapy, esophageal squamous cell carcinoma and PD-L1. Neoadjuvant chemotherapy, response, PD-1 blockade and CD8+ T cell were four latest research frontiers. The keywords reflected the progress from PD-1/PD-L1 expression to the clinical application of PD-1/PD-L1 inhibitors. The current researches mainly focus on neoadjuvant immunotherapy for esophageal cancer and development of biomarkers. Further research is warranted to determine effective predictive biomarkers or models, illustrate the molecular mechanism of combined treatment, and construct the optimal therapeutic strategy.

Conclusions

This study visually analyzed the global trend and hotspots of anti-PD-1/PD-L1 immunotherapy for esophageal cancer over the past decade. The results could guide scientists to comprehensively understand the global frontiers and determine future directions.

PD-L1 evaluation in the gastrointestinal tract: from biological rationale to its clinical application

Immune-checkpoint inhibitors targeting the PD-1/PD-L1 axis have brought significant clinical benefit in many solid cancer types, including gastrointestinal malignancies. However, it has been estimated that only 20-40% of patients respond to treatment. The pattern of expression and potential predictive value of PD-L1 as an immunohistochemical biomarker has been extensively studied in gastrointestinal neoplasms. Until now, its predictive value has been demonstrated, and is currently in use only in upper gastrointestinal malignancies (gastroesophageal adenocarcinoma and esophageal squamous cell carcinoma).

In this Review, we describe the technical aspects and challenges related to PD-L1 immunohistochemical assays, the current role of PD-L1 as a biomarker in clinical practice and we outline the main studies and clinical trials analyzing the prognostic and predictive value of PD-L1 in gastrointestinal cancers.

Roles of PTEN inactivation and PD-1/PD-L1 activation in esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is the most common type of esophageal cancer in China and developing countries. The purpose of this review is to summarize the roles of inactivation of the tumor suppressor gene, phosphatase and tensin homolog (PTEN), and activation of the programmed cell death protein 1 (PD-1) upon binding to its ligand (PD-L1) in the promotion of ESCC. Studies of ESCC performed in vitro and in vivo indicated that PTEN and PD-L1 function in the regulation of cell proliferation, invasion, and migration; the epithelial-mesenchymal transition; resistance to chemotherapy and radiotherapy; and the PI3K/AKT signaling pathway. Certain genetic variants of PTEN are related to susceptibility to ESCC, and PTEN and PD-L1 also function in ESCC progression and affect the prognosis of patients with ESCC. There is also evidence that the expression of PD-L1 and PTEN are associated with the progression of certain other cancers. Future studies should further examine the relationship of PD-L1 and PTEN and their possible interactions in ESCC.

Prognostic Value of Programmed Death Ligand-1 Expression in Solid Tumors Irrespective of Immunotherapy Exposure: A Systematic Review and Meta-Analysis

BACKGROUND

The programmed cell death-1/programmed cell death ligand-1 (PD-L1) pathway, which plays a crucial role in cancer immune surveillance, is the target of several approved immunotherapeutic agents and is used as a predictive biomarker in some solid tumors. However, its use as a prognostic marker (i.e., regardless of therapy used) is not established clearly with available data demonstrating inconsistent prognostic impact of PD-L1 expression in solid tumors.

METHODS

We conducted a systematic literature search of electronic databases and identified publications exploring the effect of PD-L1 expression on overall survival and/or disease-free survival. Hazard ratios were pooled in a meta-analysis using generic inverse-variance and random-effects modeling. We used the Deeks method to explore subgroup differences based on disease site, stage of disease, and method of PD-L1 quantification.

RESULTS

One hundred and eighty-six studies met the inclusion criteria. Programmed cell death ligand-1 expression was associated with worse overall survival (hazard ratio 1.33, 95% confidence interval 1.26-1.39; p < 0.001). There was significant heterogeneity between disease sites (subgroup p = 0.002) with pancreatic, hepatocellular, and genitourinary cancers associated with the highest magnitude of adverse outcomes. Programmed cell death ligand-1 was also associated with worse overall disease-free survival (hazard ratio 1.19, 95% confidence interval 1.09-1.30; p < 0.001). Stage of disease did not significantly affect the results (subgroup p = 0.52), nor did the method of quantification via immunohistochemistry or messenger RNA (subgroup p = 0.70).

CONCLUSIONS

High expression of PD-L1 is associated with worse survival in solid tumors albeit with significant heterogeneity among tumor types. The effect is consistent in early-stage and metastatic disease and is not sensitive to method of PD-L1 quantification. These data can provide additional information for the counseling of patients with cancer about prognosis.

Recent advances in immune-based approaches for the treatment of esophagogastric cancer

INTRODUCTION

The year 2021 will be remembered as a transformational year in the management of both esophageal and gastric cancers. Decades of failed clinical trials had seen limited therapeutic advances beyond refinement of the traditional combined modality approach. Targeted strategies against specific molecular alterations did not - with the exception of Her2 - yield the desired breakthroughs, and it was unclear what immune-based approaches would bring to this group of cancers. The presence of tumor-infiltrating lymphocytes in esophagogastric cancer demonstrates that an endogenous immune response is already occurring and potentially amplifiable by immune checkpoint inhibition. Recent data have validated this with FDA approvals in both the locoregional (CheckMate 577) and metastatic disease (CheckMate 649, KeyNote 590 and KeyNote 811) setting which have altered the therapeutic landscape.

AREAS COVERED

Here we discuss recent data and ongoing research efforts to better define the role of immune-based approaches and select the patient cohorts who might gain the most benefit from them.

EXPERT OPINION

Immunotherapy, and specifically the incorporation of the immune checkpoint inhibitors (ICI) drug class, has altered the therapeutic paradigm of many cancers in recent years. Anti-PD-1 therapies are now the new standard of care for patients with local and advanced disease.

Current status of immune checkpoint inhibitor therapy for advanced esophageal squamous cell carcinoma

Esophageal cancer is the seventh most common cancer, with an estimated 572,000 new cases, and the sixth most common cause of cancer-related deaths in 2018 with 509,000 annual worldwide deaths. Advanced esophageal squamous cell carcinoma (ESCC) is one of devastating tumors with a 5-year survival rate of less than 5% in patients with metastatic disease. Treatment options for patients with advanced ESCC are limited. Current guidelines recommend chemotherapy containing a platinum and a fluoropyrimidine agent as a first-line treatment. Recently, immune checkpoint inhibitors (ICIs), including nivolumab and pembrolizumab, have demonstrated antitumor activity and clinical efficacy in patients with advanced ESCC that is refractory or intolerant to first-line chemotherapy. ICIs are game-changers that not only transformed oncological strategy but also have a wide range of clinical potential in combination with conventional cytotoxic chemotherapy and radiotherapy. There is still an urgent, unmet need for reliable treatment options to conquer this intractable disease.

An analysis of the immunological tumor microenvironment of primary tumors and regional lymph nodes in squamous cell lung cancer

Background

Various immune cells that play a central role in antitumor immunity accumulate in primary tumors and regional lymph nodes. Such cellular accumulation and the molecular expression were analyzed to elucidate the immunological tumor microenvironment.

Methods

Fifty squamous cell lung cancer patients with complete resection were included. Resected specimens from primary lung tumors and regional lymph nodes were immunostained for immune-related molecules, such as CD8, CD103, major histocompatibility complex (MHC) class I, and programmed cell death protein ligand-1 (PD-L1), and the relationship between the prognosis and clinicopathological factors was retrospectively analyzed.

Results

Tumor-infiltrating lymphocytes and CD8+ lymphocytes, intratumoral and intrastromal CD103+ lymphocytes, tumor diameter, pathological T and N factors, and pathological stage were significant prognostic factors for the disease-specific survival (DSS) in a univariate analysis. In a multivariate analysis, intratumoral and intrastromal CD103+ lymphocytes and pathological T and N factors were independent prognostic factors of the DSS. Significant concordance was found between the PD-L1 expression of primary tumors and metastatic lymph nodes as well as among tumor-infiltrating lymphocytes, CD8+ lymphocytes and CD103+ lymphocytes. Infiltration of CD103+ lymphocytes into the tumor was significantly correlated with an increased PD-L1 expression of cancer cells in both primary tumors and reginal lymph node metastases. Both the intratumoral infiltration of CD103+ lymphocytes and PD-L1 expression of cancer cells were significantly higher in lymph node metastases than in primary tumors.

Conclusions

CD103+ lymphocyte infiltration in the primary tumor was shown to be strongly involved in the prognosis.

The upregulated expression of RFC4 and GMPS mediated by DNA copy number alteration is associated with the early diagnosis and immune escape of ESCC based on a bioinformatic analysis

Esophageal squamous cell carcinoma (ESCC) is a malignant tumor that commonly occurs worldwide. Usually, Asia, especially China, has a high incidence of esophageal cancer. ESCC often has a poor outcome because of a late diagnosis and lack of effective treatments.

To build foundations for the early diagnosis and treatment of ESCC, we used the gene expression datasets GSE20347 and GSE17351 from the GEO database and a private dataset to uncover differentially expressed genes (DEGs) and key genes in ESCC. Notably, we found that replication factor C subunit 4 (RFC4) and guanine monophosphate synthase (GMPS) were upregulated but have been rarely studied in ESCC. In particular, to the best of our knowledge, our study is the first to explore GMPS and ESCC. Furthermore, we found that high levels of RFC4 and GMPS expression may result from an increase in DNA copy number alterations. Furthermore, RFC4 and GMPS were both upregulated in the early stage and early nodal metastases of esophageal carcinoma. The expression of RFC4 was strongly correlated with GMPS. In addition, we explored the relationship between RFC4 and GMPS expression and tumor-infiltrating immune cells (TILs) in esophageal carcinoma. The results showed that the levels of RFC4 and GMPS increased with a decrease in some tumor-infiltrating cells. Upregulated RFC4 and GMPS with high TILs indicate a worse prognosis.

In summary, our study shows that RFC4 and GMPS have potential as biomarkers for the early diagnosis of ESCC and may played a crucial role in the process of tumor immunity in ESCC.

Anti-PD-1 and Anti-PD-L1 in Head and Neck Cancer: A Network Meta-Analysis

Objective

The monoclonal antibodies anti-programmed death protein-1 (anti-PD-1) nivolumab and pembrolizumab are the first immune checkpoint inhibitors (ICIs) approved for treatment of recurrent/metastatic head and neck carcinoma R/M HNSCC in first line and in platinum refractory disease. This network meta-analysis aims to investigate the efficacy of anti-PD-1- vs anti-PD-L1-based therapy in R/M HNSCC cancer patients through a systematic review of the literature to provide support for evidence-based treatment decisions. In particular, the effectiveness of ICIs for R/M HNSCC is analyzed according to the different mechanisms of action of the check-points inhibitory drugs in different subgroups of patients.

Methods

We did a systematic literature review and network meta-analysis (NMA) of randomized controlled trials (RCTs) in PubMed, ClinicalTrials.gov, Embase, Medline, the Cochrane Central Register of Controlled Trials, Web of Science. Our search identified a total of five randomized controlled trials: Keynote 040, Keynote 048, Eagle, Condor, Checkmate 141. These trials included 3001 patients. Treatment was sub-categorized into PD-L1-based, PD-1-based, and standard chemotherapy. Treatments were indirectly compared with anti-PD-L1-based therapy.

Results

The network meta-analysis demonstrated no significant differences in OS between different subgroups except for the metastatic patients in which anti-PD-1-based therapy was associated with significantly less risk of death. Furthermore, anti-PD-1-based therapy appeared to be effective in smoker patients and in human papilloma-negative (HPV) patients. Conversely, anti-PD-L1-based therapy seems to be better efficient in female patients, in locally recurrent setting and in HPV positive patients.

Conclusion

This is the first NMA study that aimed to indirectly compare anti-PD-1- and anti-PD-L1-based therapy in HNSCC patients. The results of our NMA could help define a profile of patient responder or resistant to specific classes of immune drugs and can be used to guide/design future studies in the novel scenario of precision immune-oncology.

Programmed cell death-ligand 1 expression predicts poor treatment response and prognostic value in esophageal squamous cell carcinoma patients without esophagectomy

Research on association between programmed cell death ligand 1 (PD-L1) expression in cancer cells and prognosis of esophageal squamous cell carcinoma (ESCC) has been controversial and has focused on patients with surgical resection. We aimed to investigate impact of PD-L1 on treatment response and prognostic value in ESCC and analyze which subset of patients may benefit from immunotherapy. The PD-L1 expression was evaluated by immunohistochemical analysis in all patients. Stratification analysis was performed according to whether surgery was performed. There were no significant correlations between PD-L1 expression with 3-year overall survival (OS) and progression-free survival (PFS) in 81 ESCC patients. Then stratification analysis was performed. Among these 44 patients without surgery, disease control rate (DCR) in negative PD-L1 expression group (78%) was significantly better than those (42%) in positive PD-L1 expression group (P = 0.032). There were no significant correlations between PD-L1 expression with 3-year OS and PFS in 37 ESCC patients receiving surgery. However, in 44 ESCC patients without surgery, the Kaplan-Meier method showed that 3-year OS and PFS in negative PD-L1 expression group were significantly better than those in positive PD-L1 expression group. In Cox univariate and multivariate model, PD-L1 was an independent prognosticator for inferior OS (p = 0.011; p = 0.017). Our research revealed prognostic role of PD-L1 expression in cancer cells may be variable in different treatment methods. Consequently, PD-L1 may serve as an independent prognostic factor and provide a theoretical basis for combining conventional therapy with immunotherapy targeting PD-L1 to achieve better treatment outcome in ESCC patients without esophagectomy.

Spontaneous regression of oesophageal squamous cell carcinoma

Partial or complete spontaneous regression (SR) of cancer is unusual, particularly in patients with oesophageal cancer. This case report describes a patient with biopsy-proven squamous cell carcinoma of the oesophagus which spontaneously regressed without any treatment. Regression of the primary tumour was confirmed on histological examination of the resected specimen. The process of SR remains an enigma, but potential mechanisms are considered.

Programmed Death-Ligand 1 as a Regulator of Tumor Progression and Metastasis

Programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) immune checkpoint has long been implicated in modeling antitumor immunity; PD-1/PD-L1 axis inhibitors exert their antitumor effects by relieving PD-L1-mediated suppression on tumor-infiltrating T lymphocytes. However, recent studies have unveiled a distinct, tumor-intrinsic, potential role for PD-L1. In this review, we focus on tumor-intrinsic PD-L1 signaling and delve into preclinical evidence linking PD-L1 protein expression with features of epithelial-to-mesenchymal transition program, cancer stemness and known oncogenic pathways. We further summarize data from studies supporting the prognostic significance of PD-L1 in different tumor types. We show that PD-L1 may indeed have oncogenic potential and act as a regulator of tumor progression and metastasis.

Seed- and Soil-Dependent Differences in Murine Breast Tumor Microenvironments Dictate Anti-PD-L1 IgG Delivery and Therapeutic Efficacy

We sought to determine if Stephen Paget’s “seed and soil” hypothesis of organ-preference patterns of cancer metastasis can explain the development of heterogeneity in a tumor microenvironment (TME) as well as immunotherapeutic delivery and efficacy. We established single-cell-derived clones (clones 1 and 16) from parental 4T1 murine breast cancer cells to create orthotopic primary and liver metastasis models to deconvolute polyclonal complexity cancer cells and the difference in TME-derived heterogeneities. Tumor-bearing mice were treated with anti-PD-L1 IgG or a control antibody, and immunofluorescent imaging and quantification were then performed to evaluate the therapeutic efficacy on tumor growth, the delivery of therapy to tumors, the development of blood vessels, the expression of PD-L1, the accumulation of immune cells, and the amount of coagulation inside tumors. The quantification showed an inverse correlation between the amount of delivered therapy and therapeutic efficacy in parental-cell-derived tumors. In contrast, tumors originating from clone 16 cells accumulated a significantly greater amount of therapy and responded better than clone-1-derived tumors. This difference was greater when tumors grew in the liver than the primary site. A similar trend was found in PD-L1 expression and immune cell accumulation. However, the change in the number of blood vessels was not significant. In addition, the amount of coagulation was more abundant in clone-1-derived tumors when compared to others. Thus, our findings reconfirmed the seed- and soil-dependent differences in PD-L1 expression, therapeutic delivery, immune cell accumulation, and tumor coagulation, which can constitute a heterogeneous delivery and response of immunotherapy in polyclonal tumors growing in different organs.

Immunotherapy Predictive Molecular Markers in Advanced Gastroesophageal Cancer: MSI and Beyond

Advanced gastroesophageal cancer (GEC) has a poor prognosis and limited treatment options. Immunotherapy including the anti-programmed death-1 (PD-1) antibodies pembrolizumab and nivolumab have been approved for use in various treatment settings in GEC. Additionally, frontline chemoimmunotherapy regimens have recently demonstrated promising efficacy in large phase III trials and have the potential to be added to the therapeutic armamentarium in the near future. There are currently several immunotherapy biomarkers that are validated for use in the clinical setting for GEC including programmed death ligand-1 (PD-L1) expression as well as the tumor agnostic biomarkers such as mismatch repair or microsatellite instability (MMR/MSI) and tumor mutational burden (TMB). However, apart from MMR/MSI, these biomarkers are imperfect because none are highly sensitive nor specific. Therefore, there is an unmet need for immunotherapy biomarker development. To this end, several biomarkers are currently being evaluated in ongoing trials with some showing promising predictive potential. Here, we summarize the landscape of immunotherapy predictive biomarkers that are currently being evaluated in GEC.

Investigating T Cell Immunity in Cancer: Achievements and Prospects

T cells play a key role in tumour surveillance, both identifying and eliminating transformed cells. However, as tumours become established they form their own suppressive microenvironments capable of shutting down T cell function, and allowing tumours to persist and grow. To further understand the tumour microenvironment, including the interplay between different immune cells and their role in anti-tumour immune responses, a number of studies from mouse models to clinical trials have been performed. In this review, we examine mechanisms utilized by tumour cells to reduce their visibility to CD8⁺ Cytotoxic T lymphocytes (CTL), as well as therapeutic strategies trialled to overcome these tumour-evasion mechanisms. Next, we summarize recent advances in approaches to enhance CAR T cell activity and persistence over the past 10 years, including bispecific CAR T cell design and early evidence of efficacy. Lastly, we examine mechanisms of T cell infiltration and tumour regression, and discuss the strengths and weaknesses of different strategies to investigate T cell function in murine tumour models.

Progress and Challenges of Predictive Biomarkers for Immune Checkpoint Blockade

Over the past decade, immune checkpoint blockade (ICB) therapy has revolutionized the outlook for oncology with significant and sustained improvement in the overall patient survival. Unlike traditional cancer therapies, which target the cancer cells directly, ICB acts on the immune system to enhance anti-tumoral immunity. However, the response rate is still far from satisfactory and most patients are refractory to such treatment. Unfortunately, the mechanisms underlying such heterogeneous responses between patients to ICB therapy remain unclear. In addition, escalating costs of cancer care and unnecessary immune-related adverse events also are pertinent considerations with applications of ICB. Given these issues, identifying explicit predictive biomarkers for patient selection is an urgent unmet need to increase the efficacy of ICB therapy. The markers can be classified as tumor related and non-tumor-related biomarkers. Although substantial efforts have been put into investigating various biomarkers, none of them has been found to be sufficient for effectively stratifying patients who may benefit from immunotherapy. The present write up is an attempt to review the various emerging clinically relevant biomarkers affecting the efficacy of immune checkpoint inhibitors, as well as the limitations associated with their clinical application.

Programmed cell death 1 as prognostic marker and therapeutic target in upper gastrointestinal cancers

Gastrointestinal (GIs) cancers are among the most common causes of cancer related death, and hence the importance for the identification of novel prognostic/predictive biomarkers for detection of patients at an early stage, and for using these to identify novel targeted therapies to improve the efficacy of existing chemotherapeutic regimens. Programmed cell death 1 has been reported as a potential target in several malignancies, and targeting agents are being developed, some already approved by FDA, such as: pembrolizumab, Atezolizumab, Nivolumab. Pembrolizumab that have been approved for the treatment of metastatic non-small cell lung cancer. Here we provide an overview of the mechanism of action PD-1/PD-L1, prognostic value and current progress in clinical trials using PD-1/PD-L1 inhibitors, and the resistant mechanisms at underlie the inhibitory effect of these agents in the treatment of gastrointestinal cancers.

PD-L1 as a biomarker of response to immune-checkpoint inhibitors

Immune-checkpoint inhibitors targeting PD-1 or PD-L1 have already substantially improved the outcomes of patients with many types of cancer, although only 20-40% of patients derive benefit from these new therapies. PD-L1, quantified using immunohistochemistry assays, is currently the most widely validated, used and accepted biomarker to guide the selection of patients to receive anti-PD-1 or anti-PD-L1 antibodies. However, many challenges remain in the clinical use of these assays, including the necessity of using different companion diagnostic assays for specific agents, high levels of inter-assay variability in terms of both performance and cut-off points, and a lack of prospective comparisons of how PD-L1⁺ disease diagnosed using each assay relates to clinical outcomes. In this Review, we describe the current role of PD-L1 immunohistochemistry assays used to inform the selection of patients to receive anti-PD-1 or anti-PD-L1 antibodies, we discuss the various technical and clinical challenges associated with these assays, including regulatory issues, and we provide some perspective on how to optimize PD-L1 as a selection biomarker for the future treatment of patients with solid tumours.

Clonal Expansion of Tumor-Infiltrating T Cells and Analysis of the Tumor Microenvironment within Esophageal Squamous Cell Carcinoma Relapsed after Definitive Chemoradiation Therapy

(1) Background: Comparable prognoses after definitive chemoradiation therapy (CRT) to surgery alone for esophageal squamous cell carcinoma (ESCC) have been previously reported; however, no robust prognostic markers have been established. The clonality of tumor-infiltrating lymphocytes (TILs) and tumor microenvironments (TMEs) in ESCC relapsed after CRT were examined to explore prognostic markers. (2) Methods: Clonality of TIL and TME were examined in ESCC with and without preceding CRT, as well as oral squamous cell carcinoma (OSCC) and healthy volunteers as controls. The clonality of TIL was assessed by T-cell receptor (TCR) α and β repertoire analyses and evaluated by diversity indices. The TME was assessed by quantitative polymerase chain reaction evaluating PD-L1 and CD8B. (3) Results: The clonal expansion of TIL was significantly induced within ESCCs and OSCCs, when compared to healthy volunteers, and was mostly induced within ESCCs after definitive CRT. Diversity indices of TIL were not associated with the prognosis, but the ratio of PD-L1 mRNA to CD8B mRNA in TME was significantly associated with a poor prognosis after salvage surgery (p = 0.007). (4) Conclusions: The clonal expansion of TIL is induced after definitive CRT for ESCC, and the ratio of PD-L1 mRNA to CD8B mRNA within tumor tissues is a prognostic marker candidate for salvage esophagectomy after CRT.

Progress in Multimodal Treatment for Advanced Esophageal Squamous Cell Carcinoma: Results of Multi-Institutional Trials Conducted in Japan

In Japan, the therapeutic strategies adopted for esophageal carcinoma are based on the results of multi-institutional trials conducted by the Japan Esophageal Oncology Group (JEOG), a subgroup of the Japan Clinical Oncology Group (JCOG). Owing to the differences in the proportion of patients with squamous cell carcinoma among all patients with esophageal carcinoma, chemotherapeutic drugs available, and surgical procedures employed, the therapeutic strategies adopted in Asian countries, especially Japan, are often different from those in Western countries. The emphasis in respect of postoperative adjuvant therapy for patients with advanced esophageal squamous cell carcinoma (ESCC) shifted from postoperative radiotherapy in the 1980s to postoperative chemotherapy in the 1990s. In the 2000s, the optimal timing of administration of perioperative adjuvant chemotherapy returned from the postoperative adjuvant setting to the preoperative neoadjuvant setting. Recently, the JEOG commenced a three-arm randomized controlled trial of neoadjuvant therapies (cisplatin + 5-fluorouracil (CF) vs. CF + docetaxel (DCF) vs. CF + radiation therapy (41.4 Gy) (CRT)) for localized advanced ESCC, and patient recruitment has been completed. Salvage and conversion surgeries for ESCC have been developed in Japan, and the JEOG has conducted phase I/II trials to confirm the feasibility and safety of such aggressive surgeries. At present, the JEOG is conducting several trials for patients with resectable and unresectable ESCC, according to the tumor stage. Herein, we present a review of the JEOG trials conducted for advanced ESCC.

Canine osteosarcoma checkpoint expression correlates with metastasis and T-cell infiltrate

BACKGROUND

Immune-targeted therapies are being successfully implemented into cancer clinical practice. In particular checkpoint inhibitors are employed to modulate the immune microenvironment of solid tumors. We sought to determine the expression of PD-L1, HVEM, and B7H3 in human and canine osteosarcoma, and correlate expression with clinical features and tumor infiltrating lymphocytes in naturally-occurring canine osteosarcoma.

METHODS

Flow cytometry was used to measure ligand surface expression of five human and three canine cell lines. Immunohistochemistry was utilized for expression of ligands and lymphocyte markers in thirty-seven treatment-naïve canine osteosarcoma patients.

RESULTS

All cell lines expressed all three ligands at variable levels in both species. Metastatic lesions were associated with higher expression of all three ligands in patient tumor samples. PD-L1 expression strongly correlated with B7H3 and HVEM expression, while HVEM and B7H3 were weakly correlated. Whereas peritumoral T-cell expression positively correlated with PD-L1 and HVEM tumor expression, the presence of T-cells intratumorally were rare. Furthermore, intratumor penetration by T-cells was greatest in metastatic lesions, despite log-fold increases in peritumoral T-cells. In summary, PD-L1, HVEM, and B7H3 are expressed in osteosarcoma, with metastatic disease lesions expressing higher levels. We show for the first time that these ligands expressed on osteosarcoma cells positively correlate with each other and the presence of peritumoral T cell infiltration. Furthermore, osteosarcoma appears to be an intratumoral immune desert with significant resistance to effector T cells. Multiple agents targeting checkpoints are in clinical practice, and may have immune modulating benefit in osteosarcoma.

Selected updates in molecular and genomic pathology of esophageal cancer

Recent years have seen rapid advances in the field of molecular and genomic pathology that have not only improved understanding of esophageal carcinogenesis and tumor immune environment in general but also have reshaped pathology practice and clinical management. In this article, we provide updates on three topics (1) human epidermal growth factor receptor 2, the first and most important biomarker in targeted therapy of esophageal cancer; (2) programmed death 1/programmed death ligand 1, recent biomarkers that have shown promise in treating both esophageal adenocarcinoma and esophageal squamous cell carcinoma; and (3) human papillomavirus involvement in esophageal carcinogenesis, one of the most debated topics in the field, discussed here with a renewed understanding from recent genomic and molecular data.

Pretreatment CT-Based Radiomics Signature as a Potential Imaging Biomarker for Predicting the Expression of PD-L1 and CD8+TILs in ESCC

Background

The present study constructed and validated models to predict PD-L1 and CD8+TILs expression levels in esophageal squamous cell carcinoma (ESCC) patients using radiomics features and clinical factors.

Patients and Methods

This retrospective study randomly assigned 220 ESCC patients to a discovery dataset (n= 160) and validation dataset (n= 60). A total of 462 radiomics features were extracted from the segmentation of regions of interest (ROIs) based on pretreatment CT images of each patient. The LASSO algorithm was applied to reduce the dimensionality of the data and select features. A multivariable logistic regression analysis was adopted to build radiomics signatures. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the predictive accuracy of these models.

Results

There was no significant difference between the training and validation datasets for any clinical factors in patients with ESCC. The PD-L1 expression level correlated with the differentiation degree (p= 0.011) and tumor stage (p= 0.032). Smoking status (p= 0.043) and differentiation degree (p= 0.025) were associated with CD8+TILs expression levels. The radiomics signatures achieved good performance in predicting PD-L1 and CD8+TILs with AUCs= 0.784 and 0.764, respectively. The combined model showed a favorable predictive ability compared to radiomics signatures or clinical factors alone and improved the AUCs from 0.669 to 0.871 for PD-L1 and from 0.672 to 0.832 for CD8+TILs. These results were verified in the validation dataset with the AUCs of 0.817 and 0.795, respectively.

Conclusion

CT-based radiomics features have a potential value for classifying patients according to PD-L1 and CD8+TILs expression levels. The combination of clinical factors and radiomics signatures significantly improved the predictive performance in ESCC.

Significance of druggable targets (PD-L1, KRAS, BRAF, PIK3CA, MSI, and HPV) on curatively resected esophageal squamous cell carcinoma

Background

Esophageal squamous cell carcinoma (ESCC) still remains intractable disease with few therapeutic options. Programmed death-ligand 1 (PD-L1), which is essential for immune evasion, is involved in the pathogenesis of ESCC and thus is a potential therapeutic target. PIK3CA, KRAS, and BRAF mutations, microsatellite instability (MSI) caused by deficient mismatch repair (dMMR), and human papillomavirus (HPV) can potentially upregulate PD-L1 expression, which might contribute to the clinical outcome of patients with ESCC.

Methods

We investigated the significance of the present druggable markers [PD-L1, PIK3CA, KRAS, and BRAF mutations, MSI caused by deficient dMMR, and HPV] in 64 curatively resected ESCCs, using immunohistochemistry (PD-L1 and MMR protein expression), direct sequencing (KRAS, BRAF, and PIK3CA mutations), real-time PCR (HPV infection), and MSI using quasi-monomorphic markers.

Results

PD-L1 expression, PIK3CA mutation, and MSI/dMMR were detected in 35.9, 12.5, and 17.2% of ESCCs, respectively. HPV was rarely detected (1.6%) (high-risk HPV68), whereas KRAS and BRAF mutations were not detected in ESCCs. PD-L1-positive tumors were not correlated with PIK3CA mutation or MSI/dMMR (all P > 0.05). PD-L1, PIK3CA mutation, and MSI/dMMR characterized the patients associated with light smoking, female and younger age, and younger age and well-differentiated tumors, respectively (all P < 0.05). In multivariate analysis, only PD-L1-positivity was an independent favorable prognostic factor for overall survival (OS) and disease-free survival (DFS) (P = 0.023, P = 0.014). In the PD-L1-negative ESCCs, PIK3CA mutation had a poor prognostic impact on both OS and DFS (P = 0.006, P = 0.002).

Conclusions

PIK3CA mutation may be an alternative prognostic biomarker in PD-L1-negative curatively resected ESCCs that can be optional to identify high-risk patients with worse clinical outcome who require more intensive therapy and follow-up.

Immunosuppressive Phenotype of Esophagus Tumors Stroma

Background

Tumor-associated macrophages (TAMs) and tumor-infiltrating lymphocytes (TILs) contribute significantly to the development of immunosuppressive properties of a tumor. In this study, we performed immunohistochemical analysis of immune cells of esophageal tumors stroma.

Methods

Paraffin-embedded tissue specimens from 48 esophageal squamous cell carcinoma (ESCC) patients were retrospectively collected for immunohistochemical analysis of stromal cells. For staining of macrophages, CD68, CD163, CD206, PU.1, and iNOS were used. For T cell detection, CD8, CD3, and FOXP3 were used. Also, we performed staining for PD-L1 that can be expressed on TAMs and tumor cells. Clinicopathological and survival data were collected and analyzed using the χ² and Fisher exact tests, Kaplan–Meier curves, and the log-rank test. The correlation analysis was performed with Spearman's rank correlation coefficient.

Results

We found that FOXP3 expression was associated with age (p = 0.042) and iNOS expression was associated with the disease stage (p = 0.044). In addition, FOXP3 and CD163 appeared to be markers of good prognosis (HR = 0.4420, p = 0.0325, and HR = 0.4447, p = 0.0456, respectively). Significant association between PU.1+ and CD68+ macrophages (r = 0.833; p ≤ 0.001) and between PU.1+ and CD163+ macrophages (r = 0.500; p ≤ 0.001) was established; positive association between PU.1 and CD206 expression was also observed (r = 0.250; p = 0.043).

Conclusions

Large amounts of CD163+ macrophages and FOXP3+ Т cells appear to be markers of good prognosis of ESCC. The number of PU.1+ macrophages strongly correlates with the number of CD68+ macrophages; therefore, usage of PU.1 as a potential macrophage marker can be recommended for esophageal tumors.

Esophageal Microenvironment: From Precursor Microenvironment to Premetastatic Niche

Esophageal cancer (EC) is the sixth most deadly cancer, and its incidence is still increasing year by year. Although the researches on the molecular mechanisms of EC have been widely carried out and incremental progress has been made, its overall survival rate is still low. There is cumulative evidence showing that the esophageal microenvironment plays a vital role in the development of EC. In precancerous lesions of the esophagus, high-risk environmental factors can promote the development of precancerous lesions by inducing the production of inflammatory factors and the recruitment of immune cells. In the tumor microenvironment, tumor-promoting cells can inhibit anti-tumor immunity and promote tumor progression through a variety of pathways, such as bone marrow-derived suppressor cells (MDSCs), tumor-associated fibroblasts (CAFs), and regulatory T cells (Tregs). The formation of extracellular hypoxia and acidic microenvironment and the change of extracellular matrix stiffness are also important factors affecting tumor progression and metastasis. Simultaneously, primary tumor-derived cytokines and bone marrow-derived immune cells can also promote the formation of pre-metastasis niche of EC lymph nodes, which are beneficial to EC lymph node metastasis. Further research on the specific mechanism of these processes in the occurrence, development, and metastasis of each EC subtype will support us to grasp the overall pre-cancerous prevention, targeted treatment, and metastatic assessment of EC.

Interactive Effects of PD-L1 Expression in Tumor and Immune Cells on Prognosis of Esophageal Squamous Cell Carcinoma: A One-Center Retrospective Cohort Study

Purpose

The present study aimed to investigate the prognostic effect of PD-L1 expressing in tumor and immune cells among patients with esophageal squamous cell carcinoma.

Patients and Methods

We performed a retrospective cohort study by consecutively recruiting 142 patients. The clinicopathological features and PD-L1 expression on tumor and immune cells were independently evaluated by two pathologists.

Results

The median expression rate of PD-L1 was 5% and 30% in tumor and immune cells, respectively. Patients with higher expression of PD-L1 in tumor cells had shorter disease-free and overall survival, and the HRs were 1.52 for relapse (95% CI: 0.88, 2.60) and 1.48 for death (95% CI: 0.82, 2.69). There was no significant association between the PD-L1 expression in immune cells and survival. However, among the patients with PD-L1 expression rate ≤30% in immune cells, the high expression rate of PD-L1 in tumor cells was significantly associated with the relapse and death, with HRs of 2.51 (95% CI: 1.25, 5.06) and 3.51 (95% CI: 1.57, 7.85), respectively. Among patients with PD-L1 expression rate >30% in immune cells, the PD-L1 expression in tumor cells did not show any association with the disease-free and overall survival.

Conclusion

Our study demonstrates that the integration of PD-L1 expression in tumor and immune cells could be used to predict the relapse and survival among patients with esophageal squamous cell carcinoma.

Prognostic value of tumor-infiltrating lymphocytes in esophageal cancer: an updated meta-analysis of 30 studies with 5,122 patients

Background

The prognostic role of tumor-infiltrating lymphocytes (TILs) in esophageal cancer (EC) patients is controversial; therefore, we performed a meta-analysis to obtain a consensus.

Methods

The PubMed, PubMed Central, Embase, Cochrane Library, and Web of Science databases were searched. The pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated using fixed effect or random effect models depending on the heterogeneity.

Results

A total of 30 articles comprising 5,122 patients were included in this meta-analysis. High levels of generalized TIL infiltration were associated with better overall survival (OS) (HR =0.67, 95% CI: 0.47–0.95, P=0.02) in EC patients. High CD8+ T-cell infiltration and high CD4+ T-cell infiltration were associated with better OS (HR =0.68, 95% CI: 0.60–0.78, P<0.001; HR =0.70, 95% CI: 0.57–0.85, P<0.001, respectively). However, the pooled results showed that neither CD3+ nor FOXP3+ T-cell infiltration were associated with patient survival (P>0.05). Moreover, for esophageal squamous cell carcinoma (ESCC), high CD8+ T lymphocyte infiltration in the TN (Tumor nest) or TS (Tumor stroma) significantly predicted better OS (pooled HR =0.70, 95% CI: 0.57–0.85; P=0.001; pooled HR =0.77, 95% CI: 0.65–0.91; P=0.003).

Conclusions

High levels of generalized TILs, high CD8+ T-cell infiltration and high CD4+ T-cell infiltration have the potential to serve as prognostic markers in EC patients. Moreover, high CD8+ TIL in TNs or TS can predict better OS in ESCC patients.

Synergism Between Immunotherapy and Radiotherapy in Esophageal Cancer: An Overview of Current Knowledge and Future Perspectives

Background: Esophageal cancer (EC) is an aggressive neoplasm of the gastrointestinal tract that is usually treated with a combination of chemotherapy, radiotherapy (RT), and/or surgery, according to disease status. Despite the availability of multimodal therapeutic strategies, local recurrence is frequently observed. Immunotherapy is a promising therapeutic approach that is currently highly investigated in association to standard therapies, including RT, with the aim to improve patients' outcomes. Materials and Methods: A PubMed search was performed with the following keywords in all fields: "esophageal cancer" and "radiotherapy" and "radiation" and "immunotherapy" and "PD-1" and "PD L1." For an overview of ongoing trials, an additional search on ClinicalTrials.gov website was performed using the keywords "esophageal cancer" and "immunotherapy" and "PD-L1" and "CTLA-4" and "radiation" and "radiotherapy." Emerging data from preclinical and clinical studies are suggesting a synergistic effect between immunotherapy and RT. With the aim to update the knowledge of this synergistic immune-mediated antitumor activity and discuss current challenges, the authors summarize published data concerning the basic mechanisms and the effectiveness and tolerance of the combination between immunotherapy and RT for patients with EC, followed by an overview of ongoing clinical trial. Conclusions: Published results encourage the use of personalized therapeutic approaches for EC patients in the future; results from ongoing studies will help to identify the optimal strategies for patient selection and treatment response evaluation.

Priming the tumor immune microenvironment with chemo(radio)therapy: A systematic review across tumor types

BACKGROUND

Chemotherapy (CT), radiotherapy (RT), and chemoradiotherapy (CRT) are able to alter the composition of the tumor immune microenvironment (TIME). Understanding the effect of these modalities on the TIME could aid in the development of improved treatment strategies. Our aim was to systematically review studies investigating the influence of CT, RT or CRT on different TIME markers.

METHODS

The EMBASE (Ovid) and PubMed databases were searched until January 2019 for prospective or retrospective studies investigating the dynamics of the local TIME in cancer patients (pts) treated with CT, RT or CRT, with or without targeted agents. Studies could either compare baseline and follow-up specimens - before and after treatment - or a treated versus an untreated cohort. Studies were included if they used immunohistochemistry and/or flow cytometry to assess the TIME.

RESULTS

In total we included 110 studies (n = 8850 pts), of which n = 89 (n = 6295 pts) compared pre-treatment to post-treatment specimens and n = 25 (n = 2555 pts) a treated versus an untreated cohort (4 studies conducted both comparisons). For several tumor types (among others; breast, cervical, esophageal, ovarian, rectal, lung mesothelioma and pancreatic cancer) remodeling of the TIME was observed, leading to a potentially more immunologically active microenvironment, including one or more of the following: an increase in CD3 or CD8 lymphocytes, a decrease in FOXP3 Tregs and increased PD-L1 expression. Both CT and CRT were able to immunologically alter the TIME.

CONCLUSION

The TIME of several tumor types is significantly altered after conventional therapy creating opportunities for concurrent or sequential immunotherapy.

Loss of miR-204-5p Promotes Tumor Proliferation, Migration, and Invasion Through Targeting YWHAZ/PI3K/AKT Pathway in Esophageal Squamous Cell Carcinoma

PURPOSE

MicroRNAs dysregulation has been confirmed in multiple malignancies. This paper reported the molecular mechanism of miR-204-5p in esophageal squamous cell carcinoma (ESCC).

METHODS

miR-204-5p expression in 30 ESCC tumor tissues and 10 normal tissues was downloaded from RNA-seq data. ESCC tissues/normal tissues of 97 ESCC patients were collected. TE-1 and KYSE510 cells were transfected by miR-204-5p mimic, inhibitor, siYWHAZ or their corresponding controls. The phenotype of cells was detected by CCK-8 assay, transwell experiment, and flow cytometry. Luciferase reporter gene assay and RNA-binding protein immunoprecipitation (RIP) were performed to verify the targeting relationship between miR-204-5p and YWHAZ. miR-204-5p and YWHAZ expression in tissues/cells was detected by qRT-PCR and Western blot. Xenograft tumor experiment was performed.

RESULTS

miR-204-5p expression was declined in ESCC patients and cells, which was indicated the poor outcome of patients. Compared with siNC group, TE-1 cells in miR-204-5p inhibitor group had higher OD450 value, less cell percentage in G1 phase, and more cell percentage in S phase, lower apoptosis percentage, and higher migration and invasion cell numbers. Moreover, KYSE510 cells of miR-204-5p mimic group showed lower OD450 value, more cell percentage in G1 phase and less cell percentage in S phase, higher apoptosis percentage, and lower migration and invasion cell numbers than control. YWHAZ was directly inhibited by miR-204-5p. Relative to siNC group, TE-1 cells of miR-inhibitor group exhibited higher YWHAZ protein expression, higher OD450 value, less cell percentage in G1 phase and more cell percentage in S phase, lower apoptosis percentage, higher migration and invasion cell numbers, and higher p-PI3K/PI3K and p-AKT/AKT protein expression, while siYWHAZ rescued the effects of miR-inhibitor. miR-204-5p up-regulation inhibited ESCC growth in vivo.

CONCLUSION

miR-204-5p inhibits ESCC progression by targeted inhibition of YWHAZ/PI3K/AKT.

Cost-effectiveness analysis of nivolumab in the second-line treatment for advanced esophageal squamous cell carcinoma

Background: To investigate the cost-effectiveness of nivolumab versus chemotherapy in the second-line treatment for advanced esophageal squamous cell carcinoma. Materials & methods: A Markov model reflecting the patients in the ATTRACTION-3 trial was established. Weibull survival model was employed to fit the Kaplan-Meier progression-free survival and overall survival probabilities of the nivolumab and chemotherapy strategy, respectively. Meanwhile, one-way and PSA were performed to test the uncertainty in the model. Results: Overall, the incremental effectiveness and cost of nivolumab versus chemotherapy were 0.107 quality-adjusted life-years and $14,627.90, resulting in an incremental cost-effectiveness ratio of $136,709.35/quality-adjusted life-year. Conclusion: Nivolumab is not a cost-effective treatment option compared with chemotherapy from the perspective of Chinese society.

Prognostic Value of Tumor-Infiltrating Lymphocytes Differs Depending on Lymphocyte Subsets in Esophageal Squamous Cell Carcinoma: An Updated Meta-Analysis

Background: Tumor-infiltrating lymphocytes (TILs) play a role in the anti-tumor immune response, and are often found in esophageal squamous cell carcinoma (ESCC). Methods: We performed a systematic review and meta-analysis, aiming to establish pooled estimates for survival outcomes of TILs based on their abundance and infiltrating location. A literature search of PubMed/Medline, Embase, Web of Science and the Cochrane Library was conducted. Studies that investigated the prognostic significance of generalized, CD8+, CD4+, FoxP3+, CD3+, and CD45O+ TILs in ESCC patients were included. Results: In pooled analysis, generalized TILs infiltrating the entire tumor mass were positively associated with disease-free survival (DFS), with a univariate-related hazard ratio (HR) of 0.630 [95% confidence interval (CI) 0.415-0.955], and also positively associated with overall survival (OS), with a univariate-related HR of 0.586 (0.447-0.770) and a multivariate-related HR of 0.621 (0.439-0.878). The pan-tumor, intra-tumor and peri-tumor CD8+ TILs had a favorable effect on OS, with univariate-related HRs of 0.733 (0.555-0.968), 0.797 (0.660-0.962), and 0.776 (0.635-0.948), respectively. Similar results were observed in CD8+ TILs that infiltrated the whole tumor mass, with a multivariate-related HR of 0.705 (0.524-0.947). CD4+, FoxP3+, CD3+, and CD45O+ TILs were not linked to DFS or OS. Subtypes and spatial locations of TILs seemed to influence study outcomes. Conclusions: Experimental and analytical methods of future studies should be carefully designed to avoid overestimating the effect of TILs on prognosis. Our meta-analysis confirms the prognostic efficacy of generalized TILs and CD8+ TILs in esophageal squamous cell carcinoma (ESCC) patients.

Prognostic and therapeutic molecular markers in the clinical management of esophageal cancer

Introduction: Esophageal cancer is a deadly disease with high mortality. Treatment with chemotherapy, radiation, and surgery continues to leave many patients with disease progression and recurrence. Novel treatments are needed for this patient population. The development of molecular markers are important for identifying therapeutic targets, as well as prognosis.Areas covered: This review evaluates three molecular markers in esophageal cancer: HER2, PD-L1, and MSI. The fundamentals of these markers, diagnosis, and rates of occurrence in esophageal cancer are explored. The prognostic potential of these markers is based on existing literature as well as application in clinical trials. Key trial findings pertaining to the therapeutic targets for HER2 and PD-1 as well as the role of MSI are discussed.Expert commentary: Molecular markers are changing the practice for esophageal cancer. Therapeutic targeting for HER2 and PD-L1 have shown positive results in recent clinical trials. Trials evaluating immunotherapy as first-line agents are currently underway.

Predictive biomarkers and mechanisms underlying resistance to PD1/PD-L1 blockade cancer immunotherapy

Immune checkpoint blockade targeting PD-1/PD-L1 has promising therapeutic efficacy in a variety of tumors, but resistance during treatment is a major issue. In this review, we describe the utility of PD-L1 expression levels, mutation burden, immune cell infiltration, and immune cell function for predicting the efficacy of PD-1/PD-L1 blockade therapy. Furthermore, we explore the mechanisms underlying immunotherapy resistance caused by PD-L1 expression on tumor cells, T cell dysfunction, and T cell exhaustion. Based on these mechanisms, we propose combination therapeutic strategies. We emphasize the importance of patient-specific treatment plans to reduce the economic burden and prolong the life of patients. The predictive indicators, resistance mechanisms, and combination therapies described in this review provide a basis for improved precision medicine.

Pd-ligand 1 is expressed in inflammatory cells but not in neoplastic cells in hepatocellular carcinoma: An immunohistochemical study

Nowadays, the major limit to the immunohistochemical (IHC) analysis of tissue PD-L1 is the high variability of the monoclonal antibodies commercially available. Aims of the present paper are to assess the best clone and the most suitable scoring for PD-L1 IHC determination on human hepatocellular carcinoma (HCC) among three commercially available clones, and to evaluate which PD-L1 clone is the best in predicting HCC aggressiveness in vivo. We built a tissue microarray (TMA) with 60 retrospective HCC cases, including the correspondent non-tumoral tissue. IHC was automatically performed using the following anti-PD-L1 clones: 28.8, SP142, and SP263. As results, we did not find any immunoreactivity for PD-L1 in both neoplastic and normal hepatocytes included in the TMA using the three antibodies. Positivity for PD-L1 was exclusively seen in inflammatory cells within the HCC tissue and in cirrhotic parenchyma. When a gold standard was assessed, the sensitivity of SP142, 28.8 and SP263 was 46 %, 54 % and 85 % respectively. Using the SP263 clone, the absolute number of PD-L1-positive inflammatory cells in the HCC cores was paired with the number of PD-L1-positive inflammatory cells in the corresponding non-tumoral tissue (P = 0.001). Finally, using SP263, the mean number of PD-L1-positive cells was 11.3 ± 12.6 in HCC from deceased patients, versus 4.7 ± 5.2 in alive patients (p = 0.039). SP263 is the most sensitive clone for PD-L1 IHC tissue determination in HCC, as well as the best antibody for the assessment of its biological behavior.

High serum PD-L1 level is a poor prognostic biomarker in surgically treated esophageal cancer

Background

Programmed death ligand 1 (PD‐L1) inhibitor has been approved as one of the standard therapies for various cancers. Some reports have shown that serum PD‐L1 level is associated with advanced tumor stages and poor prognosis; however, corresponding pathological information in esophageal cancer patients is lacking. Therefore, we evaluated the clinicopathological and prognostic impact of serum PD‐L1 levels in surgically treated esophageal cancer.

Methods

A total of 150 patients who underwent radical resection for esophageal cancer were included in the study. Preoperative serum PD‐L1 levels were analyzed using the enzyme‐linked immunosorbent assay kit. A cutoff level of 65.6 pg/mL was used to divide the patients into two groups, and univariate and multivariate analyses were conducted to compare the clinicopathological characteristics and prognoses between these two groups.

Results

Although significant associations between serum PD‐L1 levels and clinicopathological variables were observed, serum PD‐L1 level was significantly associated with high neutrophil counts, high CRP levels, low albumin levels, and high squamous cell carcinoma antigen levels. Furthermore, serum PD‐L1 level was associated with poor overall survival independent to TNM factors.

Conclusions

High preoperative level of serum PD‐L1 is a prognostic factor for poor overall survival in patients with surgically treated esophageal cancer.

PD-1 and PD-L1 inhibitors in oesophago-gastric cancers

Oesophago-gastric cancers (OGCs) are aggressive tumours. While better peri-operative strategies, increased number of cytotoxic agents and availability of targeted therapies have improved survival, there remains an unmet need for novel treatment approaches. Immune checkpoint inhibitors (ICIs) have marked a new era in cancer management with unprecedented results in several malignancies. Although OGC lagged behind other solid tumours, evidence has increasingly accumulated supporting the contention that modulation of the anti-cancer host immune response may be beneficial for at least some patients. Many trials have been completed in Eastern and Western countries, some of these leading to the approval of ICIs in the refractory setting, and favorable opinion from regulatory agencies is expected also in treatment-naïve, advanced OGC. Furthermore, studies are evaluating ICIs in the early stage setting and exploring the potential of combination treatments. In this article we discuss the biological bases underlying the successful development of ICIs in OGC and review the available data on PD-1 and PD-L1 monoclonal antibodies in this disease. Also, we present ongoing clinical trials of these ICIs that could shape the future treatment landscape of OGC.

Nivolumab versus chemotherapy in patients with advanced oesophageal squamous cell carcinoma refractory or intolerant to previous chemotherapy (ATTRACTION-3): a multicentre, randomised, open-label, phase 3 trial

BACKGROUND

Chemotherapy for patients with advanced oesophageal squamous cell carcinoma offers poor long-term survival prospects. We report the final analysis from our study of the immune checkpoint PD-1 inhibitor nivolumab versus chemotherapy in patients with previously treated advanced oesophageal squamous cell carcinoma.

METHODS

We did a multicentre, randomised, open-label, phase 3 trial (ATTRACTION-3) at 90 hospitals and cancer centres in Denmark, Germany, Italy, Japan, South Korea, Taiwan, the UK, and the USA. We enrolled patients aged 20 years and older with unresectable advanced or recurrent oesophageal squamous cell carcinoma (regardless of PD-L1 expression), at least one measurable or non-measurable lesion per Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1, a baseline Eastern Cooperative Oncology Group performance status of 0-1, and who were refractory or intolerant to one previous fluoropyrimidine-based and platinum-based chemotherapy and had a life expectancy of at least 3 months. Patients were randomly assigned (1:1) to either nivolumab (240 mg for 30 min every 2 weeks) or investigator's choice of chemotherapy (paclitaxel 100 mg/m² for at least 60 min once per week for 6 weeks then 1 week off; or docetaxel 75 mg/m² for at least 60 min every 3 weeks), all given intravenously. Treatment continued until disease progression assessed by the investigator per RECIST version 1.1 or unacceptable toxicity. Randomisation was done using an interactive web response system with a block size of four and stratified according to geographical region (Japan vs rest of the world), number of organs with metastases, and PD-L1 expression. Patients and investigators were not masked to treatment allocation. The primary endpoint was overall survival, defined as the time from randomisation until death from any cause, in the intention-to-treat population that included all randomly assigned patients. Safety was assessed in all patients who received at least one dose of the assigned treatment. This trial is registered with ClinicalTrials.gov, number NCT02569242, and follow-up for long-term outcomes is ongoing.

FINDINGS

Between Jan 7, 2016, and May 25, 2017, we assigned 419 patients to treatment: 210 to nivolumab and 209 to chemotherapy. At the time of data cutoff on Nov 12, 2018, median follow-up for overall survival was 10·5 months (IQR 4·5-19·0) in the nivolumab group and 8·0 months (4·6-15·2) in the chemotherapy group. At a minimum follow-up time (ie, time from random assignment of the last patient to data cutoff) of 17·6 months, overall survival was significantly improved in the nivolumab group compared with the chemotherapy group (median 10·9 months, 95% CI 9·2-13·3 vs 8·4 months, 7·2-9·9; hazard ratio for death 0·77, 95% CI 0·62-0·96; p=0·019). 38 (18%) of 209 patients in the nivolumab group had grade 3 or 4 treatment-related adverse events compared with 131 (63%) of 208 patients in the chemotherapy group. The most frequent grade 3 or 4 treatment-related adverse events were anaemia (four [2%]) in the nivolumab group and decreased neutrophil count (59 [28%]) in the chemotherapy group. Five deaths were deemed treatment-related: two in the nivolumab group (one each of interstitial lung disease and pneumonitis) and three in the chemotherapy group (one each of pneumonia, spinal cord abscess, and interstitial lung disease).

INTERPRETATION

Nivolumab was associated with a significant improvement in overall survivaland a favourable safety profile compared with chemotherapy in previously treated patients with advanced oesophageal squamous cell carcinoma, and might represent a new standard second-line treatment option for these patients.

FUNDING

ONO Pharmaceutical Company and Bristol-Myers Squibb.

PD-L1 expression, CD8+ and CD4+ lymphocyte rate are predictive of pathological complete response after neoadjuvant chemoradiotherapy for squamous cell cancer of the thoracic esophagus

BACKGROUND

Neoadjuvant chemoradiotherapy (CTRT) can effectively downstage esophageal squamous cell carcinoma (SCC) in patients with locally advanced disease and prolonged survival have been observed in patients with a pathological complete response (ypCR).

AIMS AND METHODS

This exploratory study aimed to identify immunological predictors of pCR after neoadjuvant CTRT within SCC microenvironment. The tumor regression after neoadjuvant therapy was measured according to the Mandard score system. Eighty-eight consecutive patients with SCC of the thoracic esophagus who received neoadjuvant CTRT were included in this retrospective study. Inclusion criteria were neoadjuvant CTRT and the availability of representative histological samples taken at diagnosis. We investigated immunohistochemical expression of CD4, Tbet, FoxP3, CD8, CD80, PD-L1, and PD-1, in the pretreatment biopsies and correlated the immunohistochemical profiles to patients' outcomes.

RESULTS

After neoadjuvant CTRT, 23 patients had pCR, while 65 ones had partial response, stable disease or progression. PD-L1 expression and CD8+ and CD4+ lymphocyte rate were significantly higher in patients who had ypCR compared to those who had not (10 (0-55) vs 0 (0-0), P = 0.004, 73 (36-147) vs 21 (7-47), P = 0.0006 and 39 (23-74) vs 5 (0-13), P < 0.0001 respectively). The accuracy of expression of PD-L1+, CD8+, and CD4+ lymphocyte rate in identifying responders was AUC = 0.76 (P = 0.001), AUC = 0.81 (P = 0.0001) and AUC = 0.75 (P = 0.0001), respectively. Within the ypCR group, all patients with high infiltration of CD4+ T cell recurred/relapsed while only the 38.9% of those with low CD4+ T cell infiltration did the same (P = 0.058).

CONCLUSIONS

PD-L1 expression and CD8+ and CD4+ lymphocyte rate were predictive of ypCR after neoadjuvant CTRT for SCC of the thoracic esophagus with adequate accuracy. Furthermore, recurrence/relapse was associated with high level of CD4+ T cell infiltration. However, the small sample size prevented to draw definitive conclusions; further studies are necessary to evaluate the prognostic role of these markers.