Effect of transcatheter arterial chemoembolization combined with lenvatinib plus anti-PD-1 antibodies in patients with unresectable hepatocellular carcinoma: A treatment with Chinese characteristics

Therapies for patients with unresectable hepatocellular carcinoma (uHCC) are currently popular. Current first-line standard-of-care treatments for uHCC are systematic therapies. However, treatments that combine locoregional therapy with systemic therapy are widely accepted in China and have demonstrated high rates of tumor response and conversion to resection with manageable toxicity. A literature review was performed by searching published literature in PubMed and Web of Science up to December 2023 for relevant articles on the use of triple therapy (transarterial chemoembolization combined with lenvatinib and anti-PD-1 antibodies) in uHCC. This review concentrates on the efficacy and safety of triple therapy with Chinese characteristics in patients with uHCC and describes the outcome of conversion surgery, degree of pathological necrosis, and effect prediction. This article will contribute to a comprehensive understanding of the role of triple therapy with Chinese characteristics in patients with uHCC.

Clinical impact of inflammatory and nutrition index based on metabolic tumor activity in non‑small cell lung cancer treated with immunotherapy

The aim of the present study was to explore the relationship between tumor metabolic glycolysis and inflammatory or nutritional status in patients with advanced non-small cell lung cancer (NSCLC) who received programmed death-1 (PD-1) blockade. A total of 186 patients were registered in the present study. All of patients underwent 18F-FDG PET imaging before initial PD-1 blockade, and maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were assessed as indicators of 18F-FDG uptake. As inflammatory and nutritional index, neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ration (PLR), systemic immune inflammation index (SII), prognostic nutritional index (PNI), advanced lung cancer inflammation index (ALI) and Glasgow prognostic score (GPS) were evaluated based on previous assessment. 18F-FDG uptake by MTV and TLG significantly correlated with the scores of NLR, PLR, SII, PNI and ALI, in addition to the level of albumin, lactate dehydrogenase, C-reactive protein, white blood cells, neutrophils, lymphocytes and body mass index. The count of NLR, PLR and SII was significantly higher in patients with <1 year overall survival (OS) compared with in those with ≥1 year OS, and that of PNI and ALI was significantly lower in those with <1 year OS compared with those with ≥1 year OS. High MTV under the high PLR, SII and low ALI were identified as significant factors for predicting the decreased PFS and OS after PD-1 blockade in a first-line setting. In second or more lines, high MTV was identified as a significant prognostic predictor regardless of the levels of PLR, SII, ALI and GPS. In conclusion, metabolic tumor glycolysis determined by MTV was identified as a predictor for the outcome of PD-1 blockade under the high inflammatory and low nutritional conditions, in particular, when treated with a first-line PD-1 blockade. A high MTV under high PLR and SII and low ALI in the first-line setting could be more predictive of ICI treatment than other combinations.

Increased PD-1 expression of bone marrow T-cells in acute myeloid leukaemia patients after stem cell transplantation, and its association with overall survival

BACKGROUND

Immune checkpoints are involved in mechanisms by which tumours escape from the host immune system. Our aim was to evaluate acute myeloid leukaemia (AML) patients to determine expression levels of checkpoint molecules according to diagnosis and treatments, and to identify optimal candidates for checkpoint blockade.

METHODS

Bone marrow (BM) samples were obtained from 279 AML patients at different disease status and from 23 controls. Flow cytometric analyses of PD-1 and PD-L1/PD-L2 expression were performed.

RESULTS

Programmed death-1 (PD-1) expression levels on CD8+ T-cells at AML diagnosis were increased compared to controls. PD-L1 and PD-L2 expression levels on leukaemic cells at diagnosis were significantly higher in secondary AML than in de novo AML. PD-1 levels on CD8+ and CD4+ T-cells after allo-SCT were significantly higher than those at diagnosis and after CTx. PD-1 expression on CD8+ T-cells increased in the acute GVHD group than in the non-GVHD group. The overall survival of patients with high PD-1 expression on CD8+ T-cells was significantly shorter than that of patients with low PD-1 expression.

CONCLUSIONS

In conclusion, patients who underwent allo-SCT exhibited high PD-1 expression, suggesting that allo-SCT increases PD-1 expression on T-cells, and the patients with high PD-1 expression on CD8+ T-cells after allo-SCT showed the poor prognosis. For these patients, PD-1 blockade could be an immunotherapeutic strategy.

Targeting PD-1/PD-L1 inhibits rejection in a heterotopic tracheal allograft model of lung transplantation

Immune checkpoint molecules such as programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1) have revolutionized the field of lung cancer treatment. As part of our study, we examined the role of these proteins in acute rejection in a mouse model of heterotopic tracheal transplantation. Recipient mice were untreated (Allo group) or treated with anti-PD-L1 (aPDL1 group) or PD-L1 Fc recombinant protein (PD-L1 Fc group). A further group of C57BL/6 mice received isografts (Iso group). The occlusion rate was significantly higher in the Allo group than in the Iso group (p = 0.0075), and also higher in the aPD-L1 group (p = 0.0066) and lower in the PD-L1 Fc group (p = 0.030) than in the Allo group. PD-L1 Fc recombinant protein treatment significantly decreased interleukin-6 and interferon-γ levels and reduced the CD4+/CD8+ T cell ratio, without increasing PD-1 and T-cell immunoglobulin mucin 3 expression in CD4+ T cells. These data suggest that PD-L1 Fc recombinant protein decreases the levels of inflammatory cytokines and the proportion of CD4+ T cells without exhaustion. The PD-L1-mediated immune checkpoint mechanism was associated with rejection in the murine tracheal transplant model, suggesting a potential novel target for immunotherapy in lung transplantation.

Regulatory Rheumatoid Factor is Specific to PD-1 and Uses PD-1 Pathway to Control CD4 T Lymphocytes

BACKGROUND

We have earlier discovered a new factor of autoimmunity downregulation, called regulatory rheumatoid factor (regRF). Being anti-idiotypic antibodies, regRF restricts the expansion of CD4+ T lymphocytes to the idiotype of which it is specific, according to the negative feedback principle. It has been shown that only activated CD4+ T lymphocytes are the target of regRF. However, it is still not clear the way regRF distinguishes activated cells from naive ones. RegRF molecules, apart from individual paratopes specific to unique sequences of B- and T-cell receptors, have a shared paratope. We assume that regRF by means of a shared paratope recognizes one of the surface activation molecules of CD4+ T lymphocytes and initiates the cell death. Programmed death-1 (PD-1) has been tested as a potential receptor of the shared regRF paratope and transmitter of the negative regRF signal into activated CD4+ T lymphocytes.

METHODS

The specificity of the shared regRF paratope to PD-1 was determined by ELISA. T cell activation was performed with immobilized anti-CD3ε antibodies. Flow cytometry was used to study the effect of regRF on PD-1+CD4+ lymphocytes.

RESULTS

We found that regRF binds to PD-1. IgG Fc fragments carrying epitopes specific to the shared paratope of regRF compete with PD-1 for binding to regRF. It follows that regRF recognizes specifically PD-1 by means of a shared paratope. RegRF-containing serum reduced the number of PD-1+CD4+ lymphocytes in proportion to their increase resulting from the action of anti-CD3ε antibodies.

CONCLUSION

RegRF uses PD-1 pathway to control activated CD4+ T lymphocytes.

Development of a high-affinity anti-bovine PD-1 rabbit-bovine chimeric antibody using an efficient selection and large production system

Immune checkpoint molecules PD-1/PD-L1 cause T-cell exhaustion and contribute to disease progression in chronic infections of cattle. We established monoclonal antibodies (mAbs) that specifically inhibit the binding of bovine PD-1/PD-L1; however, conventional anti-PD-1 mAbs are not suitable as therapeutic agents because of their low binding affinity to antigen. In addition, their sensitivity for the detection of bovine PD-1 is low and their use for immunostaining PD-1 is limited. To address these issues, we established two anti-bovine PD-1 rabbit mAbs (1F10F1 and 4F5F2) and its chimeric form using bovine IgG1 (Boch1D10F1), which exhibit high binding affinity. One of the rabbit mAb 1D10F1 binds more strongly to bovine PD-1 compared with a conventional anti-PD-1 mAb (5D2) and exhibits marked inhibitory activity on the PD-1/PD-L1 interaction. In addition, PD-1 expression in bovine T cells could be detected with higher sensitivity by flow cytometry using 1D10F1. Furthermore, we established higher-producing cells of Boch1D10F1 and succeeded in the mass production of Boch1D10F1. Boch1D10F1 exhibited a similar binding affinity to bovine PD-1 and the inhibitory activity on PD-1/PD-L1 binding compared with 1D10F1. The immune activation by Boch1D10F1 was also confirmed by the enhancement of IFN-γ production. Finally, Boch1D10F1 was administered to bovine leukemia virus-infected cows to determine its antiviral effect. In conclusion, the high-affinity anti-PD-1 antibody developed in this study represents a powerful tool for detecting and inhibiting bovine PD-1 and is a candidate for PD-1-targeted immunotherapy in cattle.

Efficacy and safety of TACE combined with lenvatinib and PD-1 inhibitors for unresectable recurrent HCC: A multicenter, retrospective study

BACKGROUND

There is no consensus on the optimal regimen for unresectable recurrent hepatocellular carcinoma (HCC), so this retrospective study aimed to evaluate the efficacy and safety of transarterial chemoembolization (TACE) combined with lenvatinib and PD-1 inhibitors (T-L-P) versus TACE combined with lenvatinib (T-L) or TACE alone.

METHOD

Data were collected from 204 patients with unresectable recurrent HCC who received T-L-P, T-L, or TACE alone at three medical centers from January, 2019 to December, 2020 for analysis. The survival outcomes, tumor response, and adverse events were compared between three groups, and risk factors were further investigated.

RESULTS

The median overall survival in the T-L-P, T-L, and TACE alone groups were not reached, 25.6, and 15.7 months, respectively (p < 0.001). The median progression-free survival in the T-L-P, T-L, and TACE alone groups were 24.1, 17.3, and 13.7 months, respectively (p < 0.001). The best objective response rate in the T-L-P, T-L, and TACE alone groups were 70.4%, 48.9%, and 42.5%, respectively. The best disease control rate in the T-L-P, T-L, and TACE alone groups were 100.0%, 97.8%, and 87.5%, respectively. There was no significant difference between the T-L-P and T-L groups for Grade 3/4 adverse events.

CONCLUSION

T-L-P regimen was safe and superior to T-L or TACE alone in improving survival for unresectable recurrent HCC patients.

Clinical and immunological characteristics of PD-1 associated fulminant type 1 diabetes mellitus

OBJECTIVES

Programmed death 1 (PD-1) associated fulminant type 1 diabetes (PFD) is a rare acute and critical in internal medicine, and its clinical characteristics are still unclear. This study aims to analyze the clinical characteristics of PFD patients to improve clinical diagnosis and treatment.

METHODS

We retrospectively analyzed the clinical data of 10 patients with PFD admitted to the Second Xiangya Hospital of Central South University, combined with the data of 66 patients reported in the relevant literature, analyzed and summarized their clinical and immunological characteristics, and compared the patients with PFD with different islet autoantibody status.

RESULTS

Combined with our hospital and literature data, a total of 76 patients with PFD were reported, with the age of (60.9±12.1) years old, 60.0% male and body mass index of (22.1±5.2) kg/m2. In 76 patients, the most common tumors were lung cancer (43.4%) and melanoma (22.4%). Among PD-1 inhibitors, the most common drugs are nivolumab (37.5%) and pembrolizumab (38.9%). 82.2% of PFD patients developed diabetes ketoacidosis. The median onset time from PD-1 related inhibitor treatment to hyperglycemia was 95 (36.0, 164.5) d, and the median treatment cycle before the onset of diabetes was 6 (2.3, 8.0) cycles. 26% (19/73) of PFD patients had positive islet autoantibodies, and the proportion of ketoacidosis in the positive group was significantly higher than that in the negative group (100.0% vs 75.0%, P<0.05). The onset time and infusion times of diabetes after PD-1 inhibitor treatment in the autoantibody positive group were significantly lower than those in the autoantibody negative group (28.5 d vs 120.0 d; 2 cycles vs 7 cycles, both P<0.001).

CONCLUSIONS

After initiation of tumor immunotherapy, it is necessary to be alert to the occurrence of adverse reactions of PFD, and the onset of PFD with islet autoantibody positive is faster and more serious than that of patients with autoantibodies negative. Detection of islet autoantibodies and blood glucose before and after treatment with PD-1 inhibitors is of great value for early warning and prediction of PFD.

Case report: A rare case of sintilimab-induced gastric stenosis and literature review

Sintilimab is a fully human IgG4 monoclonal antibody against programmed death-1 (PD-1) used to treat classical Hodgkin's lymphoma and various solid tumors. With increasing use of sintilimab, some rare adverse reactions have been reported. Here, we report a case of a 50-year-old woman with squamous non-small cell lung cancer (NSCLC) (metastasis to pericardium and pleura) who received two cycles of 200 mg sintilimab immunotherapy combined with albumin-bound paclitaxel and carboplatin chemotherapy and one cycle of sintilimab monotherapy. She was diagnosed with Sjogren's syndrome (with symptoms of fever, dry mouth, dysphagia, and eating difficulty) after three cycles' treatment and received standard steroidal therapy. Prior to admission, the patient experienced severe stomach discomfort with vomiting and was hospitalized. Upper gastrointestinal iodine angiography showed significant gastric stenosis as well as lower esophageal stenosis. Subsequent ultrafine gastroscopy revealed ulceration at the stenotic site and an absence of normal peristalsis of the gastric wall. Pathological examination of the lesions showed reactive changes, including ulceration, fibrosis, and inflammatory cell infiltration. After multidisciplinary consultation, it was considered that the patient's gastric stenosis with inflammatory fibrosis changes was due to a sintilimab-induced immune hyperinflammatory reaction. The patient had been treated with standard steroidal therapy since suffering from Sjogren's syndrome, but the gastric stenotic changes were not relieved. The patient then received regular bouginage of esophago-cardiac stenosis under gastroscopy to physically reexpand the fibrous hyperplasia and stenotic site, enabling normal eating function. To our knowledge, this is the first case of gastric stenosis in a patient with squamous NSCLC after using sintilimab and may help clinicians better understand potential immune-related adverse events due to sintilimab and improve assessment and management.

Recent Advancement of PD-L1 Detection Technologies and Clinical Applications in the Era of Precision Cancer Therapy

Programmed death-1 is a protein found on the surface of immune cells that can interact with its ligand, programmed death-ligand 1 (PD-L1), which is expressed on the plasma membrane, the surface of secreted cellular exosomes, in cell nuclei, or as a circulating soluble protein. This interaction can lead to immune escape in cancer patients. In clinical settings, PD-L1 plays an important role in tumor disease diagnosis, determining therapeutic effectiveness, and predicting patient prognosis. PD-L1 inhibitors are also essential components of tumor immunotherapy. Thus, the detection of PD-L1 levels is crucial, especially in the era of precision cancer therapy. In recent years, innovations have been made in traditional immunoassay methods and the development of new immunoassays for PD-L1 detection. This review aims to summarize recent research progress in tumor PD-L1 detection technology and highlight the clinical applications of PD-L1.

Downregulation of AT-rich interaction domain 2 underlies natural killer cell dysfunction in oral squamous cell carcinoma

The immune system plays a significant role in controlling oral squamous cell carcinoma (OSCC) initiation and progression. Natural killer (NK) cells actively participate in antitumor immunity but become dysfunctional or exhausted in the tumor microenvironment. To explore the mechanisms of NK cell dysfunction in OSCC, we characterized the expression and function of AT-rich interaction domain 2 (ARID2) in NK cells in a murine OSCC model. ARID2 was downregulated in tongue NK cells compared with splenic NK cells. Notably, ARID2 was significantly decreased in NK cells with an exhausted phenotype and weakened antitumor function. ARID2 knockdown resulted in the upregulation of programmed cell death protein 1 (PD-1) and downregulation of interferon-gamma (IFN-γ), tumor necrosis factor (TNF), granzyme B and perforin in NK cells. As a result, ARID2 knockdown impaired NK cell cytotoxicity. Besides, ARID2 overexpression suppressed the expression of PD-1 and lymphocyte-activation gene 3, and promoted the expression of IFN-γ, TNF, granzyme B and perforin in NK cells which were adoptively transferred into OSCC-bearing mice. Taken together, our study implies that the OSCC microenvironment triggers ARID2 downregulation in intratumoral NK cells. In turn, ARID2 downregulation results in PD-1 upregulation on NK cells and subsequently impairs NK cell cytotoxicity. Therefore, we uncovered a novel mechanism of NK cell dysfunction in OSCC.

PD-1 Deficiency in Regulatory T Cells May be Involved in the Pathogenesis of Takayasu's Arteritis

OBJECTIVES

This study aims to investigate whether PD-1 expressions are abnormal in patients with TAK.

METHODS

PD-1 expression was analyzed by flow cytometry. Serum cytokines IL-10, IL-7, IL-2, IL-15, CCL2, CCL3, and CXCL10 were detected using a cytokine cytometric bead array. Immunohistochemistry staining analysis was used to test PD-1 and programmed death-ligand 1 (PD-L1) expression in the aorta of three patients with TAK and three patients with atherosclerosis as controls.

RESULTS

The mean fluorescence intensity of PD-1 in CD4⁺PD-1⁺ cells was decreased in patients with TAK and the frequency of CD4⁺Foxp3^-PD-1⁺ cells among CD4⁺T cells was also decreased in peripheral blood relative to healthy controls (P < .05). The percentage of CD4⁺CD25⁺Foxp3⁺PD-1⁺ cells in the CD4⁺CD25⁺T cell population was lower in patients with TAK than in healthy control and was lower in active TAK group (P < .05). Comparing PD-1 and PDL-1 expression in aorta tissue showed that patients with TAK tended to have lower levels than patients with atherosclerosis, but the difference was not significant (P > .05). Patients with TAK had higher serum levels of IL-10, IL-7, CCL2, and CCL3 (P < .05).

CONCLUSIONS

Abnormal expression of PD-1 in serum and aorta tissue of patients with TAK may contribute to TAK pathogenesis.

KEY POINTS

PD-1 expression in both peripheral blood and aorta tissue of TAK patients decreased relative to healthy controls, indicating that PD-1 might be involved in TAK pathogenesis.

Recent advances in the management of gastric adenocarcinoma patients

Gastric adenocarcinomas are a significant cause of cancer and cancer death, globally. The curative approach for those with diagnosed localized disease is with surgical resection and an adjunctive approach of perioperative chemotherapy, postoperative adjuvant therapy, or postoperative chemoradiation. Unfortunately, a universal standard approach is lacking for adjunctive therapy which in part has limited the progress achieved in this area. Metastatic disease is common in the Western world at diagnosis. Metastatic disease is treated palliatively with systemic therapy. Targeted therapy has stalled in approvals in gastric adenocarcinomas. Recently, we have seen the exploration of promising targets along with the addition of immune checkpoint inhibitors in select patients. Here, we review recent advances seen in gastric adenocarcinomas.

Role of cytotoxic T cells and PD-1 immune checkpoint pathway in papillary thyroid carcinoma

Background

Lymphocytic thyroiditis (LT) is frequently seen in the tumor microenvironment (TME) of papillary thyroid carcinomas (PTCs). However, the characteristic of these tumor-infiltrating lymphocytes (TILs) is not well understood.

Objective

We aim to define the TME of PTC cases by characterizing the TILs.

Design

This is a cross-sectional observational study.

Patients

We enrolled 29 PTC (23 having concurrent LT), 14 LT, and 13 hyperplastic nodules with LT (HN) patients from January 2016 to December 2020.

Measurements

Immunohistochemical (IHC) expression of CD8, FoxP3, PD-1, and PD-L1 was studied in PTC with LT and compared with HN. PD-1 and PD-L1 expression was correlated at the mRNA level by quantitative real-time PCR. Immunophenotyping of TILs was done in FNAC samples of PTC and LT by flow cytometry.

Results

IHC revealed the presence of CD8+ cytotoxic T lymphocytes (CTLs) and FoxP3+ T regulatory cells (Tregs) in 83% and 52% of PTC with LT cases, respectively. Flow cytometric analysis of the PTC samples revealed a significant abundance of CTL compared with Treg and a higher CTL with lower Treg counts compared with LT. On IHC, PD-1 positivity was noted in 56.5% of PTC with LT cases, while intermediate PD-L1 positivity was found in 70% of the cases. There was a significant upregulation of PD-1 mRNA in PTC with LT. A significant correlation was noted with PD-L1 expression with lymph node metastasis and presence of Treg cells.

Conclusions

Increased expression of PD-1 and PD-L1 in the TME of PTC may provide a potential molecular mechanism for tumor survival despite the predominance of CTLs, possibly through their inactivation or exhaustion.

Chemotherapy combined with immunotherapy in primary female urethral squamous cell carcinoma: a case report

Primary female urethral carcinomas are uncommon and have a low morbidity rate. Most of these patients have advanced illness with high invasion and a poor prognosis. There is no standard treatment, and multimodal therapy is recommended. The use of radiotherapy and chemotherapy were mostly reported in previous studies on advanced female urethral squamous cell carcinoma. We report that chemotherapy combined with a programmed death-1 (PD-1) inhibitor was effective in treating metastatic female urethral squamous cell carcinoma. During four cycles, we used systemic chemotherapy of albumin-paclitaxel + carboplatin in combination with a PD-1 inhibitor (toripalimab 240 mg) every 3 weeks, and a complete response was achieved. We performed a genetic test on the patient who had a tumor mutation burden of 5.7 mutations/Mb, tumor proportion score of 20%, and combined positive score of 20% (22C3). No recurrence or distant metastasis was found after 20 months of follow-up. In conclusion, in patients with positive PD-1 ligand 1 expression in primary female urethral squamous cell carcinoma, chemotherapy combined with PD-1 inhibitors may be effective. Larger sample studies are required to determine PD-1 ligand 1 expression and the curative effect of PD-1 inhibitors, as well as their effect on survival.

Development of Monoclonal B-cell Lymphocytosis Shortly After Treatment with Nivolumab and Subsequent Progression to Chronic Lymphocytic Leukemia

INTRODUCTION

Immune checkpoint inhibitors, such as programmed death (PD)-1 inhibitor nivolumab, are currently widely used in treatment of various malignancies. Due to their widespread application, any new potential adverse effects due to these agents necessitate careful assessment.

CASE REPORT

We report a case of an 81-year-old man with recurrent high-risk malignant melanoma who underwent a 12-month adjuvant treatment with nivolumab. Shortly after the course of nivolumab, he developed monoclonal B-cell lymphocytosis (MBL) which subsequently progressed to chronic lymphocytic leukemia (CLL).

MANAGEMENT AND OUTCOME

The patient is currently doing clinically well in Rai stage 0. Malignant melanoma remains in remission.

CONCLUSION

Considering the pathophysiologic plausibility of nivolumab inducing B-cell dysregulation via PD-1 inhibition, we suggest further studies on potential association between nivolumab and B-cell malignancies.

First-line or second-line PD-1 inhibition in advanced oesophageal squamous cell carcinoma: A prospective, multicentre, registry study

WHAT IS KNOWN AND OBJECTIVE

First-line and second-line immunotherapy with programmed death-1 (PD-1) inhibitors both improve overall survival in patients with advanced oesophageal squamous cell cancer (ESCC). This study explored survival differences between first-line and second-line PD-1 inhibition in advanced ESCC.

METHODS

This registry study included 167 patients with advanced ESCC who were exposed to PD-1 inhibitors in either a first-line or a second-line setting between 15 January 2019 and 31 October 2020. The primary endpoint was overall survival, and secondary endpoints included overall tumour response, progression-free survival (PFS) and PFS2. A propensity score-matching (PSM) analysis was performed using the nearest-neighbour method.

RESULTS AND DISCUSSION

Sixty-one patients started first-line treatment with chemotherapy and a PD-1 inhibitor (Group 1), while 106 started chemotherapy as the first-line choice and received a PD-1 inhibitor as the second-line choice (Group 2). The median PFS was 7.1 months in Group 1 and 4.1 months in Group 2 (log-rank p = 0.001). The median PFS2 was 7.1 months in Group 1 and 7.4 months in Group 2 (log-rank p = 0.4). Before PSM, the median overall survival was 13.5 months in Group 1 and 14.1 months in Group 2 (log-rank p = 0.9), and the sensitivity analysis showed consistent results (14.0 vs. 14.1 months). After PSM, the median overall survival rates for Group 1 (n = 61) and Group 2 (n = 61) were 13.5 and 13.1 months (log-rank p = 0.7) respectively.

WHAT IS NEW AND CONCLUSION

In this study, patients with advanced ESCC who received first-line or second-line PD-1 inhibitors seemed to have comparable overall survival.

The current management and biomarkers of immunotherapy in advanced gastric cancer

BACKGROUND

Gastric carcinoma (GC) is the fourth most common cause of cancer-related death worldwide. Most patients are diagnosed at later stage, because of few treatment options, the prognosis is poor. In recent years, however, Immune checkpoint inhibitors(ICIs), such as anti- programmed death-1 (PD-1), anti-PD-L1, and anti-cytotoxic T lymphocyte antigen 4, have emerged as promising therapeutic agents in GC. Here, we summary the current treatment and advances of immune checkpoint inhibitors in the advanced stage of GC.

METHODS

WANFANG MED ONLINE, CNKI, NCBI PUBMED and clinicaltrials.gov were used to search literature spanning from 2000 to 2021, and all literatures about "advanced gastric or gastro-oesophageal junction cancer, Immune checkpoint inhibitors, PD-1, PD-L1, Cytotoxic T lymphocyte antigen 4, immune therapy" with detailed data were included.

RESULTS

Nivolumab and pembrolizumab have been recommended for the third line or subsequent therapy in advanced GC. Nivolumab plus chemotherapy has been recommended for the first line treatment in advanced GC in China. Many other ICIs have been demonstrating encouraging efficacy. PD-L1, MSI-H, Epstein Barr virus, and tumor mutational burden (TMB) status maybe potential biomarkers for response to clinical outcomes for ICIs in GC.

CONCLUSION

ICIs have shown encouraging treatment efficacy and manageable safety profile in GC. Some biomarkers including PD-L1, MSI-H, EBV, and TMB status could evaluate the efficacy of ICIs in GC.

Effect of immune checkpoint inhibitors in patients with gastric hepatoid adenocarcinoma: a case report and literature review

Gastric hepatoid adenocarcinoma (GHAC) is a highly aggressive histological subtype of gastric cancer (GC) with similar tissue morphology to hepatocellular carcinoma. GHAC frequently produces alpha-fetoprotein (AFP) and has a poor prognosis; however, standardized treatment remains elusive. We report a male patient in his early 60s with GHAC who received immunotherapy, and the curative effect was evaluated. He was admitted because of progressive fatigue and dizziness for 2 months. He had experienced spontaneous epigastric pain with muscular defense of the epigastrium and accompanying tenderness 1 year earlier and underwent radical gastrectomy. Immunohistochemistry showed that hepatocyte-specific marker (Hep) was highly-expressed, indicating probable GHAC. Additionally, imaging suggested GC recurrence or gastric stump cancer. Radioimmunoassay indicated an AFP level of >1210.00 µg/L, and liver biopsy was performed following abdominal contrast-enhanced computed tomography. Pathology showed a few hepatocytes and proliferative fibrous connective tissue. The patient received three cycles of chemotherapy, with no obvious improvement. The possibility of surgical treatment was excluded, and immunotherapy or palliative treatment was selected. He received 11 cycles of a programed death-1 (PD-1) monoclonal antibody, and the effect of treatment was satisfactory. The mechanism of action of immunotherapy in GHAC warrants further investigation.

Increased lactate in AML blasts upregulates TOX expression, leading to exhaustion of CD8+ cytolytic T cells

Recently, the role of lactate as merely an end product of cancer cell metabolism has been reassessed. Lactate has been implicated in more biological processes than previously understood and drives tumor progression. Here, we demonstrated that the bone marrow lactate concentrations in acute myeloid leukemia (AML) patients were substantially higher than those in their healthy control counterparts. Moreover, AML blasts from bone marrow expressed significantly higher lactate dehydrogenase-A (LDHA) levels. Further studies revealed that LDHA expression was regulated through the HIF1α pathway. Elevated lactate levels were indicative of alterations in CD8⁺ T cell cytolytic phenotype and activity. An in vitro study showed that the lactate treatment group had significantly higher percentages of CD8⁺ TEM and CD8⁺ TEMRA cells as well as higher PD-1 expression in these cells than the control group. Lactate induced the loss of the effector function of CD8⁺ T cells by altering lytic granule exocytosis. T cell dysfunction is characterized by an increase in terminally differentiated phenotypes, sustained expression of PD-1, and accelerated decline of cytolytic competence. Moreover, the TOX gene was found to be correlated with lactate production and implicated in CD8⁺ T cell dysfunction. AML patients in complete remission after chemotherapy had markedly lower lactate concentrations, reduced CD8⁺ TEM and CD8⁺ TEMRA cells and PD-1 expression, and increased perforin and granzyme B. However, no difference was found in the relapsed patients. The study presented here has established lactate as a predictive biomarker for patient response to antitumor therapies and demonstrated that targeting this gene in AML patients could be a meaningful precision therapeutic strategy.

Assessment of PD-L1 expression in patients with neuroblastoma and renal tumors

BACKGROUND

Programmed death 1 (PD-1) is a co-receptor which is located at the surface of cells like natural killer, monocytes, T and B cells. It has two ligands including programmed death ligand-1 (PD-L1) and ligand-2 (PD-L2). T cell functions are inhibited by activation of PD-1/PD-L1 pathway and this pathway is used by viruses and some tumor cells in order to escape from immune eradication. In our study we evaluated PD-L1 expression in the tissue specimens of patients with Wilms tumor, neuroblastoma and other renal tumors.

METHODS

Totally 60 patients who were followed up at Gazi University Hospital with the diagnosis of neuroblastoma, Wilms tumor and other renal tumors were included. PD-L1 expression was examined in tumor samples of the patients.

RESULTS

Positive staining with PD-L1 was detected only in two male patients. Both of them had neuroblastoma and advanced stage disease. None of the patients with Wilms tumor and other renal tumors had positive PD-L1 staining.

CONCLUSIONS

Unlike adult tumors, PD-L1 expression is not common in childhood tumors due to differences in immune system between children and adults. Further studies are needed to establish the importance and effects of PD-1/PD-L1 pathway in pediatric tumors.

PD-1 Blockade Restores the Proliferation of Peripheral Blood Lymphocyte and Inhibits Lymphocyte Apoptosis in a BALB/c Mouse Model of CP BVDV Acute Infection

Acute infection of bovine viral diarrhea virus (BVDV) is associated with immune dysfunction and can cause peripheral blood lymphopenia and lymphocyte apoptosis. Our previous study has confirmed that programmed death-1 (PD-1) blockade inhibits peripheral blood lymphocytes (PBL) apoptosis and restores proliferation and anti-viral immune functions of lymphocytes after BVDV infection in vitro. However, the situation in vivo remains to be further studied and confirmed. Therefore, in this study, we established a BALB/c mouse model of acute BVDV infection with cytopathic (CP) BVDV (strain NADL) and non-cytopathic (NCP) BVDV (strain NY-1). Then, we examined the mRNA and protein levels of PD-1 and programmed death-ligand 1 (PD-L1) in peripheral blood mononuclear cells (PBMC) from BVDV-infected mice and analyzed the effects of PD-1 blockade on the proportions of CD3+, CD4+, and CD8+ T cell subsets, the apoptosis and proliferation of PBL, and the production of IL-2 and IFN-γ. We found that leukopenia, lymphocytopenia, and thrombocytopenia were developed in both CP and NCP BVDV-infected mice at day 7 of post-infection. The mRNA and protein expression of PD-1 and PD-L1 were significantly upregulated in CP and NCP BVDV-infected mice. Moreover, PD-1/PD-L1 upregulation was accompanied by leukopenia and lymphopenia. Additionally, PD-1 blockade inhibited PBL apoptosis and virus replication, restored the proportions of CD3+, CD4+, and CD8+ T cell subsets, and increased IFN-γ production and p-ERK expression in BVDV-infected mice. However, blocking PD-1 did not significantly affect PBL proliferation and IL-2 production in NCP BVDV-infected mice. Our findings further confirmed the immunomodulatory role of PD-1 in peripheral blood lymphocytopenia in vivo and provided a scientific basis for exploring the molecular mechanism of immune dysfunction caused by acute BVDV infection.

Application of immune checkpoint inhibitors in colorectal cancer

Over the past decade, immunotherapy has been shown to have antitumor activity in a variety of solid tumors, such as melanoma, renal cell carcinoma, and non-small cell lung cancer, keeping a lead in a new era of tumor immunotherapy. Colorectal cancer with high microsatellite instability (MSI-H) or mismatch repair deficient (dMMR) is sensitive to immune checkpoint inhibitors (ICIs). ICIs monotherapy and ICIs combination therapy have made breakthroughs in the treatment of MSI-H/dMMR CRC. At present, a variety of ICIs have been approved for first- and post-line treatment in patients with CRC. However, MSI-H/dMMR type tumors only account for 5% of metastatic CRC, and the most CRCs were microsatellite stable (MSS) or mismatch repair proficient (pMMR). Many clinical trials are exploring effective treatments for patients with MSS/pMMR CRC, and the combination of ICIs and drugs with different mechanisms is expected to improve the efficacy of MSS/pMMR CRC patients. In the future, attention should be paid to finding the potential therapeutic markers of ICIs and the drug resistance mechanism of ICIs, so as to break through the immune tolerance of MSS/pMMR CRC patients.

Pericardial Toxicities Associated With Immune Checkpoint Inhibitors: A Pharmacovigilance Analysis of the FDA Adverse Event Reporting System (FAERS) Database

Introdution: Immune checkpoint inhibitors (ICIs) have significantly improved clinical outcomes for a wide range of cancers but can also lead to serious or fatal immune-related adverse events (irAEs). Although ICI-related pericardial toxicities have been reported, the clinical features are not well characterized in real-world studies.

Objective: To characterize the main features of ICI-related pericardial toxicities and identify factors associated with death.

Methods: Data from January 1, 2011 to March 31, 2020 in the FDA Adverse Event Reporting System database were retrieved for disproportionality analysis. We used the reporting odds ratio and the information component (IC) to evaluate the association between ICIs and pericardial adverse events. Clinical characteristics of patients with ICI-associated pericardial toxicities were collected and compared between fatal and non-fatal groups. The time to onset following different ICI regimens was further investigated.

Results: We identified a total of 705 ICI-associated pericardial toxicities which appeared to influence more men (53.90%) than women (36.03%), with a median age of 63 (interquartile range [IQR] 54–69) years. Patients with lung cancer accounted for the largest proportion (55.6%). ICI therapies were detected with pharmacovigilance signals of pericardial toxicities, corresponding to IC₀₂₅ = 2.11 and ROR 4.87 [4.51–5.25]. Nevertheless, there was a lack of association between anti-CTLA-4 and pericardial toxicities. There was no difference in onset time among all ICI regimens. However, TTO of fatal cases (25 days (interquartile range [IQR] 6–70)) occurred statistically earlier than non-fatal cases (42 days (IQR 12–114), p = 0.003).

Conclusion: ICI monotherapy (PD-1/PD-L1 therapy) and combination therapy can lead to pericardial toxicities that can result in serious outcomes and tend to occur early. Early recognition and management of ICI-related pericardial disorders should attract clinical attention. The findings require further clinical surveillance for the quantification.

Clinical Perspectives to Overcome Acquired Resistance to Anti-Programmed Death-1 and Anti-Programmed Death Ligand-1 Therapy in Non-Small Cell Lung Cancer

Immune checkpoint inhibitors have changed the paradigm of treatment options for non-small cell lung cancer (NSCLC). Monoclonal antibodies targeting programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1) have gained wide attention for their application, which has been shown to result in prolonged survival. Nevertheless, only a limited subset of patients show partial or complete response to PD-1 therapy, and patients who show a response eventually develop resistance to immunotherapy. This article aims to provide an overview of the mechanisms of acquired resistance to anti-PD-1/PD-L1 therapy from the perspective of tumor cells and the surrounding microenvironment. In addition, we address the potential therapeutic targets and ongoing clinical trials, focusing mainly on NSCLC.

Ibrutinib improves the efficacy of anti-CD19-CAR T-cell therapy in patients with refractory non-Hodgkin lymphoma

The efficacy and side effects of the second‐time humanized CD19 chimeric antigen receptor (CD19‐CAR) T‐cell therapy after unsuccessful first‐time anti‐CD19‐CAR T‐cell therapy and subsequent ibrutinib salvage treatment were observed in patients with refractory B‐cell lymphoma. In our study, 3 patients with refractory mantle cell lymphoma (MCL) and 4 patients with refractory follicular lymphoma (FL) reached stable disease (SD), partial remission (PR), or progression of disease (PD) after first‐time humanized anti‐CD19‐CAR T‐cell therapy. They received ibrutinib as a salvage treatment and kept an SD in the following 7‐16 mo, but their disease progressed again during ibrutinib salvage treatment. All 7 patients received a second‐time humanized anti‐CD19‐CAR T‐cell therapy, which was the same as their first‐time anti‐CD19‐CAR T‐cell therapy. In total, 3 MCL patients and 3 FL patients reached complete response (CR) with the second‐time anti‐CD19‐CAR T‐cell therapy combined with ibrutinib, whereas 1 FL patient reached PR. There were no differences in the transduction efficiency and proliferation between the 2 instances of anti‐CD19‐CAR T‐cell therapy. However, the second‐time anti‐CD19‐CAR T‐cell therapy led to higher peaks of anti‐CD19‐CAR T cells and anti‐CD19‐CAR gene copies, but also to higher grades of cytokine release syndrome (CRS) and more serious hematological toxicity. The successful outcome of the second‐time anti‐CD19‐CAR T‐cell therapy might suggest that the previous ibrutinib treatment improved the activities of anti‐CD19‐CAR T cells.

Expression and significance of PD-1 and PD-L1 in patients with recurrent spontaneous abortion: A protocol for systematic review and meta-analysis

BACKGROUND

Recurrent spontaneous abortion (RSA) accounts for the most common complication of early pregnancy in humans. As an immune checkpoint pathway, programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1) can be exploited by tumor cells to evade immuno-surveillance. Many studies have shown that the expression of PD-1/PD-L1 is involved in RSA. However, the correlation between the expression of PD-1/PD-L1 and RSA is still controversial. We conducted meta-analysis to further explore the correlation between the expression of PD-1/PD-L1 and RSA, to provide a basis for clinical prevention and treatment.

METHODS

We will search PubMed, Embase, Web of Science, Google Scholar, Chinese National Knowledge Infrastructure, Chinese VIP Information, Wanfang Database, and Chinese Biomedical Literature Database for related published studies before February 2021. Two review authors will search and assess relevant studies independently. Case control studies and cohort studies will be included. The Revman 5.3 software was applied to carry out the meta-analysis for the included literature.

RESULTS

The findings of this systematic review will be disseminated in a peer-reviewed publication and/or presented at relevant conferences.

CONCLUSION

This study will provide a new theoretical basis for the prevention and treatment of RSA.

TRIAL REGISTRATION NUMBER

DOI 10.17605/OSF.IO/CZD23.Ethics and dissemination: Formal ethical approval is not required, as the data are not individualized.

High Expression of PD-L1 Is Associated with Better Survival in Pancreatic/Periampullary Cancers and Correlates with Epithelial to Mesenchymal Transition

Periampullary cancers (PACs) are characterized by tumor-infiltrating lymphocytes (TILs), severe fibrosis, and epithelial to mesenchymal transition (EMT). The immune checkpoint marker programmed death-1 (PD-1) and its ligands 1 and 2 have gained popularity in cancers with TILs. Evidence suggests a strong relationship between immune checkpoint markers and EMT in cancers. Here, we evaluated the expression and prognostic significance of immune checkpoint and EMT markers in PAC using an automated image analyzer. Formalin-fixed, paraffin-embedded surgically excised PAC tissues from laboratory archives (1998–2014) were evaluated by immunohistochemical staining for PD-1, PD-L1, and PD-L2 in a tissue microarray. In total, 115 PAC patients (70 males and 45 females) with an average age of 63 years were analyzed. Location, gross type, size, radial resection margin, N-M stage, lymphatic invasion, vascular invasion, perineural invasion, histologically well-differentiated severe inflammation, and high PD-L1 expression were significantly associated with recurrence. Higher PD-L1 expression, but not PD-1 and PD-L2, was significantly related to better overall survival (OS) and disease-free survival (DFS). PD-L1 and PD-L2 were significantly related to EMT markers. Aside from other clinicopathologic parameters, high PD-L1 expression was significantly related to better OS and DFS of PAC patients. Moreover, immune checkpoint markers were significantly associated with EMT markers. Therefore, PD-L1 expression can be a good prognostic marker to guide future immune target-based therapies in PAC patients.

Expression of Programmed Death-Ligand 1 and Programmed Death-1 in Patients with Extramammary Paget's Disease

Background:

Extramammary Paget's disease (EMPD) is a rare skin cancer and sometimes has fatal prognosis. For progressive cases, therapeutic options are limited. In recent years, treatment with an anti-programmed death-1 (PD-1) antibody has improved the prognosis of various malignancies. In addition, correlations between PD-ligand 1 (PD-L1) expression in tumor cells and favorable responses to anti-PD-1 therapy have been reported for several cancers. There have been a few case series of analysis of PD-L1 expression in patients with EMPD.

Aims:

The purpose of this study was to investigate the relationship between the EMPD and PD-L1/PD-1 expression in Japanese EMPD patients.

Materials and Methods:

We investigated 39 patients with EMPD by immunohistochemical staining of PD-L1 and PD-1. We counted the number of tumor cells that were positive for PD-L1 and the number of tumor-infiltrating mononuclear cells (TIMCs) that were positive for PD-L1 and PD-1. We also analyzed correlations between the expression of PD-L1 and PD-1 in EMPD and patients’ characteristics.

Results:

We found that none of the Paget's cells expressed PD-L1. All of the specimens contained TIMCs, and some of the TIMCs expressed PD-L1 and PD-1. However, there was no correlation between the expression of PD-L1/PD-1 in TIMCs and patients’ characteristics.

Conclusion:

Although tumor cells did not express PD-L1 and the expression of PD-L1/PD-1 in TIMCs did not correlate with patients’ characteristics, future clinical studies should be carried out to explore another immune escape pathway in EMPD.

High Expression of Pd-1 in Circulating Cells of Patients With Advanced Colorectal Cancer Receiving Adjuvant Therapy

Among all cancer types, colorectal cancer is the third most common in men and the second most common in women globally. Generally, the risk of colorectal cancer increases with age, and colorectal cancer is modulated by various genetic alterations. Alterations in the immune response serve a significant role in the development of colorectal cancer. In primary cancer types, immune cells express a variety of inhibitory molecules that dampen the immune response against tumor cells. Additionally, few reports have demonstrated that classical chemotherapy promotes the immunosuppressive microenvironment in both tissues and immune cells. This study assessed the expression levels of genes using RT-qPCR associated with the immune system, including interferon-γ, programmed death-1, β2-microglobulin, human leukocyte antigen-A, CD3e, CD28 and intracellular adhesion molecule 1, in patients with colorectal cancer, as these genes are known to serve important roles in immune regulation during cancer incidence. Gene expression analysis was performed with the whole blood cells of patients with colorectal cancer and healthy volunteers. Compared with the normal controls, programmed death-1was highly expressed in patients with advanced-stage colorectal cancer. Furthermore, the expression of programmed death-1 was higher in patients receiving adjuvant therapy, which suggests the therapy dampened the immune response against tumor cells. The results of the present study indicate that classical adjuvant therapies, which are currently used for patients with colorectal cancer, should be modulated, and a combination of classical therapy with anti-programmed death-1 antibody should be conducted for improved management of patients with colorectal cancer.

Clonal expansion of bone marrow CD8+ T cells in acute myeloid leukemia patients at new diagnosis and after chemotherapy

CD8⁺ T cells are crucial adaptive immune effectors and express receptors (T cell receptors, TCRs) that specifically recognize and eradicate tumor cells. The diversity of the TCR repertoire is generated by specialized genetic diversification mechanisms, which lead to an extremely variable TCR repertoire that is capable of recognizing a wide range of antigens. However, the variations in CD8⁺ TCR diversity and their clinical implications in acute myeloid leukemia (AML) patients remain unknown. CD8⁺ T cells were enriched from 10 healthy donors and 31 AML patients at diagnosis and after chemotherapy, and TCRβ deep sequencing was performed to analyze CD8⁺ T cell clonal expansion and TCR repertoire diversity. Diminished TCR repertoire diversity and increased T cell clone expansion were noted in the bone marrow of AML patients. In relapsed patients, T cells were found to be more clonally expanded after chemotherapy than at new diagnosis. Moreover, significantly more expanded TCRβ clonotypes were noted in CD8⁺ PD-1⁺ T cells than in CD8⁺ PD-1^- T cells regardless of the time of examination. Our systematic T cell repertoire analysis may help better characterize CD8⁺ T cells before and after chemotherapy in AML, which may provide insights into therapeutic strategies for hematological malignancies.

Killing efficiency affected by mutually modulated PD-1 and PD-L1 expression via NKT-hepatoma cell interactions

Aim: To explore the expression of programmed death-1 (PD-1) or programmed death ligand 1 (PD-L1), natural killer T (NKT) and hepatoma cells in coculture system, and the influence of abolishing PD-1 on antitumor efficiency. Materials & methods: CRISPR/Cas9 technology, flow cytometry, ELISA, CCK-8 assay and mouse models were performed to investigate the interactions between PD-1/PD-L1 expression on NKT and hepatoma cells, respectively. Results: The NKT and hepatoma cells mutually affected the expression of PD-1/PD-L1. The killing effect was positively correlated with NKT-mediated PD-L1 expression on hepatoma cells. Conclusion: Hepatoma cells in different genetic background responded differently to NKT-induced PD-L1 stimulation, and those cells with lower PD-L1 expression fail to PD-1 blocking intervention. Additionally, the killing effect was more time-efficient with PD-1 knockout than with monoclonal antibody blockade.

Adverse cardiac events in the treatment of non-small cell lung cancer with programmed death-1and programmed death-ligand 1 inhibitors: A protocol for systematic review and meta-analysis

BACKGROUND

Programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1) inhibitors are immune therapies that have shown great promise in the treatment of multiple cancers. However, immune-related adverse events of PD-1 and PD-L1 inhibitors may limit their use in non-small cell lung cancer (NSCLC). Given the rising number of clinical trials in recent years, it is essential to perform a meta-analysis to provide assess the cardiotoxicity of PD-1/ PD-L1 inhibitors in NSCLC therapy.

METHOD AND ANALYSIS

The ClinicalTrials.gov, Embase, PubMed, and Cochrane Central Register of Controlled Trials repositories will be searched from their inception to December 2019. The bibliography of the searching process will be imported into Endnote X9 software. Two reviewers independently will screen the literature, extract data, and conduct the risk of bias for every added study. The data analysis will be analyzed using Stata15.0 software. Specific adverse cardiac events will be identified, with particular attention on atrial fibrillation, cardiac arrest, cardiac failure, and pericarditis. This review will be performed as per the Preferred Reporting Item for Systematic Review and meta-analysis statement recommendations.

ETHICS AND DISSEMINATION

This study will provide support for the cardiotoxicity linked to the treatment of NSCLC using PD-1/PD-L1 inhibitors. The data in the meta-analysis will be retrieved from completed and published clinical trials; therefore, ethical review and patient informed consent will not be required.

PROSPERO NUMBER

CRD42020156397.

Efficacy of a programmed death-1 checkpoint inhibitor in a case of cutaneous squamous cell carcinoma harboring mutations of TP53 and BRCA2

Immune checkpoint blockades were reported to result in clinical responses in inoperable and metastatic cutaneous squamous cell carcinoma (cSCC). This report describes an 87-year-old woman with recurrent cSCC that was initially responsive to cetuximab (the monoclonal antibody against epithelial growth factor receptor) but eventually became refractory to cetuximab and multiple subsequent salvage chemotherapy regimens. Next-generation sequencing of the tumor discovered three single-nucleotide mutations in TP53, copy number amplification in Src, and a heterozygous deletion in BRCA2. Because of the high mutation burden of her neoplasm (35.2 mutations per megabase), we treated her with a programmed death-1 (PD-1) checkpoint inhibitor, pembrolizumab, for 10 months. The tumor regressed 3 months later and complete pathological remission was achieved 10 months after starting treatment. As of writing, the patient has been disease free for 17 months after discontinuing treatment. This is the first reported case of heterozygous deletion of BRCA2 in cSCC. The high mutation burden and BRCA2 mutation might explain why this tumor was highly sensitive to anti-PD-1 treatment.

Mechanism of acquired resistance to nivolumab in lung squamous cell carcinoma: case report and review of the literature

Background: Immune checkpoint inhibitors targeting PD-1 and PD-L1 have noticeably improved the treatment landscape of advanced non-small-cell lung cancer, including lung squamous cell carcinoma (SCC). Although patients with immune checkpoint therapy can achieve long-term survival, acquired resistance has been recognized more frequently, while the underlying mechanisms are currently poorly understood. Materials and methods: Here, we report a patient with metastatic lung SCC treated with nivolumab as a first-line treatment for 28 months. Conclusion: The analysis of specimens prenivolumab and postnivolumab treatment suggests that genetic alterations in SOX2 and CDKN2A/CDKN2B and changes in the tumor microenvironment could be reasons for the acquired resistance to nivolumab observed in the lung SCC patient.

Expression of PD-1 and PD-L1 on Tumor-Infiltrating Lymphocytes Predicts Prognosis in Patients with Small-Cell Lung Cancer

Introduction

Immune therapy has shown good results in small-cell lung cancer (SCLC), but the impact of immune microenvironment of the disease is unclear. In this work, we detected expression of programmed death 1 (PD-1), PD-ligand 1 (PD-L1), and other immune biomarkers of cancer. We also analyzed the correlations between these markers and survival in SCLC.

Patients and Methods

Protein expression of PD-1, PD-L1, PD-L2, CD3, CD4, CD8, and FOXP3 was analyzed in surgical tissues from 102 SCLC patients by immunohistochemistry.

Results

Positive expression of PD-1 on tumor-infiltrating lymphocytes (TILs) was found in 40.2% of patients; 37.3% of patients showed positive expression of PD-L1 on TILs; and 3.9% showed positive expression of PD-L1 on tumor cells. PD-L2 protein was not expressed on tumor cells or TILs. Survival analysis showed that positive expression of PD-L1 on TILs was correlated with longer relapse-free survival (RFS) (p=0.004). Positive expression of PD-1 combined with a high ratio of lymphocytes (CD3, p=0.004; CD4, p=0.011; CD8, p=0.009; FOXP3, p=0.009) was associated with significantly better RFS than negative expression of PD-1 combined with a lower ratio of lymphocytes. Positive expression of PD-L1 combined with a high ratio of lymphocytes (CD3, p<0.001; CD4, p=0.001; CD8, p=0.002; FOXP3, p=0.001) was associated with significantly better RFS than negative expression of PD-L1 combined with a lower ratio of lymphocytes. All patients’ stage were between I and III.

Conclusion

PD-1 and PD-L1 expression might be good prognostic factors in SCLC.

[Interleukin-12 over-expression in malignant melanoma B16 cells reduces programmed death-1 expression on T cells in mice with immune reconstitution]

OBJECTIVE

To investigate whether interleukin-12 (IL-12) over-expression in malignant melanoma B16 cells affects the expression level of programmed death-1 (PD-1) on T cells in mice during immune microenvironment reconstruction.

METHODS

B16 cells were transfected with an IL-12 expression lentiviral vector, and IL-12 over-expression in the cells was verified qPCR and ELISA. Plate cloning assay was used to compare the cell proliferation activity between B16 cells and B16/IL-12 cells. The expression of IL-12 protein in B16/IL-12 cells-derived tumor tissue were detected by ELISA. C57BL/6 mice were inoculated with B16 cells or B16/IL-12 cells, and 14 days later the proportion of T cells with high expression of PD-1 in the tumor-draining lymph nodes was detected by flow cytometry. Mouse models of immune reconstitution established by 650 cGy X-ray radiation were inoculated with B16 (B16+RT group) or B16/IL-12 (B16/IL-12+RT group) cells, with the mice without X-ray radiation prior to B16 cell inoculation as controls. Tumor growth in the mice was recorded at different time points, and on day 14, flow cytometry was performed to detect the proportion of T cells with high PD-1 expression in the tumor-draining lymph nodes and in the tumor tissue.

RESULTS

B16 cells infected with the IL-12-overexpressing lentiviral vector showed significantly increased mRNA and protein levels of IL-12 (P &lt; 0.001) without obvious changes in cell viability (P&gt;0.05). B16/IL-12 cells expressed higher levels of IL-12 than B16 cells in vivo (P &lt; 0.01). In the tumor-bearing mouse models, the proportion of CD4 ⁺ PD-1⁺ T cells was significantly lower in B16/IL-12 group than in B16 group (P &lt; 0.01). In the mice with X-ray radiation-induced immune reconstitution, PD-1 expressions on CD4⁺ T cells (P &lt; 0.05) and CD8+ T cells (P &lt; 0.01) were significantly higher in B16+ RT group than in the control mice and in B16/IL-12+RT group (P &lt; 0.01 or 0.001); the tumors grew more slowly in B16/IL-12+RT group than in B16 + RT group (P &lt; 0.001).

CONCLUSIONS

During immune microenvironment reconstruction, overexpression IL-12 in the tumor microenvironment can reduce the percentage of PD-1 ⁺ T cells and suppress the growth of malignant melanoma in mice.

Immune Checkpoints Contribute Corneal Immune Privilege: Implications for Dry Eye Associated with Checkpoint Inhibitors

The eye is provided with immune protection against pathogens in a manner that greatly reduces the threat of inflammation-induced vision loss. Immune-mediated inflammation and allograft rejection are greatly reduced in the eye, a phenomenon called 'immune privilege'. Corneal tissue has inherent immune privilege properties with underlying three mechanisms: (1) anatomical, cellular, and molecular barriers in the cornea; (2) an immunosuppressive microenvironment; and (3) tolerance related to regulatory T cells and anterior chamber-associated immune deviation. This review describes the molecular mechanisms of the immunosuppressive microenvironment and regulatory T cells in the cornea that have been elucidated from animal models of ocular inflammation, especially those involving corneal transplantation, it also provides an update on immune checkpoint molecules in corneal and systemic immune regulation, and its relevance for dry eye associated with checkpoint inhibitor therapy.

Long-term efficacy and predictive correlates of response to nivolumab in Japanese patients with esophageal cancer

The long-term efficacy of nivolumab in esophageal squamous cell carcinoma and its association with disease biomarkers are currently not well known. Therefore, we investigated the association in Japanese patients with treatment-refractory advanced esophageal cancer who participated in an open-label, single-arm, multicenter phase II study. Patients received nivolumab 3 mg/kg i.v. every 2 weeks until disease progression or unacceptable toxicity, and were followed up for 2 years after the initial dosing of the last patient. Archival tissue samples were collected before treatment and analyzed for programmed death ligand-1 (PD-L1) and CD8⁺ status of tumors and tumor-infiltrating lymphocytes (TILs) and human leukocyte antigen class 1. Efficacy end-points included objective response rate (ORR), overall survival (OS), progression-free survival (PFS), time to response, and duration of response. Of 65 enrolled patients (83% male), 64 were evaluable for efficacy and 41 (63%) for biomarkers. The ORR, median OS, and survival rate were 17.2%, 10.78 months, and 17.2%, respectively. Time to response was 1.45 months and duration of response was 11.17 months. The PD-L1 positivity of tumor cells was possibly associated with better PFS (2.04 vs 1.41 months, cut-off 1%) and OS (11.33 vs 6.24 months, cut-off 1%). Median OS was prolonged in patients with a median number of TILs greater than 63.75% vs 63.75% or less (11.33 vs 7.85 months). Nivolumab showed continued long-term efficacy, as seen by the stability of PFS and OS, in Japanese patients with esophageal squamous cell carcinoma. Further investigation of PD-L1 tumor expression and TILs as potential biomarkers for predicting patients likely to benefit from nivolumab therapy is warranted.

The Combination Options and Predictive Biomarkers of PD-1/PD-L1 Inhibitors in Esophageal Cancer

Esophageal cancer (EC) is one of the most common cancers with poor survival in the world. Nowadays, a generous number of clinical trials are underway on the use of immunotherapy in EC patients, especially the programmed death-1/programmed death-ligand 1 (PD-1/PD-L1) inhibitors. However, only a few patients could benefit from single-agent therapy. Others need combination therapies to enhance the response rate and survival. In this review, we focus on PD-1/PD-L1 inhibitors and its combination options in EC patients. We also summarized the potential predictive biomarkers for PD-1/PD-L1 inhibitors treatment.

Type 1 diabetes pathogenesis and the role of inhibitory receptors in islet tolerance

Type 1 diabetes (T1D) affects over a million Americans, and disease incidence is on the rise. Despite decades of research, there is still no cure for this disease. Exciting beta cell replacement strategies are being developed, but in order for such approaches to work, targeted immunotherapies must be designed. To selectively halt the autoimmune response, researchers must first understand how this response is regulated and which tolerance checkpoints fail during T1D development. Herein, we discuss the current understanding of T1D pathogenesis in humans, genetic and environmental risk factors, presumed roles of CD4+ and CD8+ T cells as well as B cells, and implicated autoantigens. We also highlight studies in non-obese diabetic mice that have demonstrated the requirement for CD4+ and CD8+ T cells and B cells in driving T1D pathology. We present an overview of central and peripheral tolerance mechanisms and comment on existing controversies in the field regarding central tolerance. Finally, we discuss T cell- and B cell-intrinsic tolerance mechanisms, with an emphasis on the roles of inhibitory receptors in maintaining islet tolerance in humans and in diabetes-prone mice, and strategies employed to date to harness inhibitory receptor signaling to prevent or reverse T1D.

Immune Modulation by Telomerase-Specific Oncolytic Adenovirus Synergistically Enhances Antitumor Efficacy with Anti-PD1 Antibody

The clinical benefit of monotherapy involving immune checkpoint inhibitors (ICIs) such as anti-programmed death-1 antibody (PD-1 Ab) is limited to small populations. We previously developed a telomerase-specific oncolytic adenovirus, Telomelysin (OBP-301), the safety of which was confirmed in a phase I clinical study. Here, we examined the potential of OBP-502, an OBP-301 variant, as an agent for inducing immunogenic cell death (ICD) and synergistically enhancing the efficacy of OBP-502 with PD-1 Ab using CT26 murine colon cancer and PAN02 murine pancreatic cancer cell lines. OBP-502 induced the release of ICD molecules such as adenosine triphosphate (ATP) and high-mobility group box protein 1 (HMGB1) from CT26 and PAN02 cells, leading to recruitment of CD8-positive lymphocytes and inhibition of Foxp3-positive lymphocyte infiltration into tumors. Combination therapy involving OBP-502 intratumoral administration and PD-1 Ab systemic administration significantly suppressed the growth of not only OBP-502-treated tumors but also tumors not treated with OBP-502 (so-called abscopal effect) in CT26 and PAN02 bilateral subcutaneous tumor models, in which active recruitment of CD8-positve lymphocytes was observed even in tumors not treated with OBP-502. This combined efficacy was similar to that observed in a CT26 rectal orthotopic tumor model involving liver metastases. In conclusion, telomerase-specific oncolytic adenoviruses are promising candidates for combined therapies with ICIs.

Correlation of CpG methylation of the Pdcd1 gene with PD-1 expression on CD8+ T cells and medical laboratory indicators in chronic hepatitis B infection

BACKGROUND

The negative signal provided by some co-inhibitory factors such as programmed cell death-1 (PD-1) has been associated with chronic hepatitis B (CHB) infection induced-T cell exhaustion, although the correlation of CpG methylation of the Pdcd1 gene with PD-1 expression and medical laboratory indicators in CHB infection has not yet been elucidated.

METHODS

Blood samples from 20 CHB infection patients and 20 spontaneous clearance (SC) patients were collected. Percentages of PD-1-positive CD8⁺ T cells were analyzed by flow cytometry. The percentage of CpG methylation at the Pdcd1 locus was analyzed by bisulfite sequencing. Student's t test, Pearson and Spearman's correlation, and Mann-Whitney tests were used in the statistical analysis.

RESULTS

Percentages of PD-1-positive CD8⁺ T cells in peripheral blood T cells were significantly higher in CHB patients than in the SC group (p < 0.001). The methylation level of Pdcd1 was significantly lower in CHB patients (p < 0.001) and the methylation level of Pdcd1 was negatively correlated with PD-1 expression level in CD8⁺ T cells (p < 0.001) and hepatitis-B surface antigen (HBsAg) (p < 0.001).

CONCLUSIONS

The results of the present study suggest that Pdcd1 methylation is correlated with PD-1 expression on CD8⁺ T cells and correlated with HBsAg and alanine aminotransferase. The results may provide new ideas regarding anti-PD-1 inhibitors, and epigenetic regulators such as demethylation inhibitors could represent more successful therapeutic strategies in hepatitis B infection patients.

BTLA Expression in Stage I-III Non-Small-Cell Lung Cancer and Its Correlation with PD-1/PD-L1 and Clinical Outcomes

Background

B and T lymphocyte attenuator (BTLA) is a novel immune checkpoint with an unclear role in non–small-cell lung cancer (NSCLC). In contrast, the programmed death-1 (PD-1)/programmed death ligand-1 (PD-L1) checkpoint is a potentially curative immunotherapy target in NSCLC. Our study investigated BTLA expression and its relationship with PD-1/PD-L1, tumor-infiltrating lymphocytes (TILs), and clinicopathological features.

Methods

The protein expressions of BTLA, PD-1, and PD-L1 were evaluated by immunohistochemistry (IHC) and TIL abundance was scored in paraffin-embedded tissues from surgically resected specimens from 87 patients with stage I–III NSCLC.

Results

BTLA was expressed in tumor cells in 35 patients with NSCLC (40.2%). In addition, 42 patients (48.3%) were positive for PD-1 in TILs and 31 (35.6%) were positive for PD-L1 in tumor cells. BTLA was overexpressed in patients with lymphatic invasion (P=0.045) and an advanced tumor stage (P=0.034). High expression of BTLA was positively correlated with a high level of PD-L1 (P=0.011). Patients with positive BTLA expression had a shorter relapse-free survival (RFS) than those with negative BTLA expression (P=0.029). Moreover, patients negative for both BTLA and PD-L1 had a longer RFS than patients who were positive for BTLA or PD-L1 or for both checkpoints (P=0.012). The same pattern was shown for overall survival (P=0.031).

Conclusion

High BTLA expression may predict poor prognosis in patients with NSCLC and may represent a new immunotherapy target.

PD-1-positive Natural Killer Cells have a weaker antitumor function than that of PD-1-negative Natural Killer Cells in Lung Cancer

Antibodies targeting the immune checkpoint inhibitor, programmed cell death 1 (PD-1), have provided a breakthrough in the treatment of lung cancer. However, the function of PD-1 in natural killer (NK) cells of cancer patients remains unclear. Herein, we analyzed the expression of PD-1 on the NK cells in the peripheral blood of patients with lung cancer and found that the level of PD-1⁺ NK cells in patients was significantly higher than that in healthy individuals. Moreover, these PD-1⁺ NK cells demonstrated a weaker ability to secrete interferon-gamma (INF-γ), granzyme B, and perforin, and exhibited lower CD107a expression. Importantly, in patients with lung cancer, the percentage of PD-1⁺ NK cells was significantly positively correlated with the concentration of IL-2 in the plasma, which was also higher than that in healthy individuals. In addition, IL-2 could increase the expression of PD-1 on NK cells in vitro, indicating that high IL-2 level in the plasma is largely responsible for the abundance of PD-1⁺ NK cells in patients with lung cancer. These findings demonstrate intriguing mechanisms for understanding the expression of PD-1 on NK cells and the function of PD-1⁺ NK cells in lung cancer. This study confirms and extends previous studies demonstrating that PD-1 can negatively regulate the antitumor function of NK cells.

Expression of Programmed Death-Ligand 1 in Cutaneous Squamous Cell Carcinoma Arising in Sun-Exposed and Nonsun-Exposed Skin

Background

A recent clinical trial has shown the efficacy of an anti-programmed death-1 (PD-1) antibody against advanced squamous cell carcinoma (SCC). The expression of PD-ligand 1 (PD-L1) in tumor cells correlates with a favorable response to anti-PD-1 therapy in various malignancies. In recent studies, it has been shown that SCC frequently expresses PD-L1. However, there has been no previous study focusing on the difference in PD-L1 expression between SCC in sun-exposed skin and that in nonsun-exposed areas.

Aims

The purpose of this study was to investigate the relationship between sun-exposure status and PD-L1 expression in patients with SCC.

Materials and Methods

We investigated 80 patients with SCC (40 patients with SCC in sun-exposed skin and 40 patients with SCC in nonsun-exposed skin) by immunohistochemical staining for PD-L1. Fisher's exact test was used for statistical analyses of the differences between the two groups.

Results

Patients with SCC in sun-exposed skin showed a significantly higher expression level of PD-L1 in tumor cells than did patients with SCC in nonsun-exposed skin (P = 0.0133).

Conclusions

We found that the expression level of PD-L1 in patients with SCC in sun-exposed skin was higher than in patients with SCC in nonsun-exposed skin. Practical data are needed for appropriate applications of new therapeutic options for SCC.

CCR2 inhibition reduces tumor myeloid cells and unmasks a checkpoint inhibitor effect to slow progression of resistant murine gliomas

Immunotherapy directed at the PD-L1/PD-1 axis has produced treatment advances in various human cancers. Unfortunately, progress has not extended to glioblastoma (GBM), with phase III clinical trials assessing anti-PD-1 monotherapy failing to show efficacy in newly diagnosed and recurrent tumors. Myeloid-derived suppressor cells (MDSCs), a subset of immunosuppressive myeloid derived cells, are known to infiltrate the tumor microenvironment of GBM. Growing evidence suggests the CCL2-CCR2 axis is important for this process. This study evaluated the combination of PD-1 blockade and CCR2 inhibition in anti-PD-1-resistant gliomas. CCR2 deficiency unmasked an anti-PD-1 survival benefit in KR158 glioma-bearing mice. CD11b⁺/Ly6C^hi/PD-L1⁺ MDSCs within established gliomas decreased with a concomitant increase in overall CCR2⁺ cells and MDSCs within bone marrow of CCR2-deficient mice. The CCR2 antagonist CCX872 increased median survival as a monotherapy in KR158 glioma-bearing animals and further increased median and overall survival when combined with anti-PD-1. Additionally, combination of CCX872 and anti-PD-1 prolonged median survival time in 005 GSC GBM-bearing mice. In both models, CCX872 decreased tumor associated MDSCs and increased these cells within the bone marrow. Examination of tumor-infiltrating lymphocytes revealed an elevated population, increased IFNγ expression, indicating enhanced cytolytic activity, as well as decreased expression of exhaustion markers in CD4⁺ and CD8⁺ T cells following combination treatment. These data establish that combining CCR2 and PD-1 blockade extends survival in clinically relevant murine glioma models and provides the basis on which to advance this combinatorial treatment toward early-phase human trials.

Expression of PD-1/PD-L1 in head and neck squamous cell carcinoma and its clinical significance

OBJECTIVE

To investigate the role of programmed death-1 (PD-1), programmed death-ligand 1 (PD-L1), and P16 in patients with head and neck squamous cell carcinoma (HNSCC).

METHODS

A total of 95 paraffin-embedded samples of tumorous tissue of HNSCC were collected. Expression levels of PD-1, PD-L1, and P16 were determined by immunohistochemistry.

RESULTS

A significantly higher proportion of PD-1 among patients infected with the human papillomavirus was found. PD-L1 expression is closely associated with the primary site of the tumor, postoperative recurrence, survival, PD-1 expression and P16 expression. Univariable analysis indicated that T stage, N stage, tumor node metastasis stage, tumor differentiation, and PD-L1 expression were all shown to be prognostic variables for overall survival in patients with HNSCC. In the multivariate analysis, only N stage (P = 0.010) and PD-L1 expression (P = 0.001) were found to be independent prognostic variables for overall survival. In addition, for disease recurrence, multivariate analysis showed that only PD-L1 expression was the associated independent risk factor. For the patients with negative PD-L1 expression, Kaplan-Meier analysis revealed that they had significantly worse outcomes in terms of overall survival (P = 0.001). Similarly, compared with the patients with positive PD-L1 expression, those with negative PD-L1 expression had a higher probability of recurrence (P = 0.026).

CONCLUSIONS

The expression of PD-L1, PD-1, and P16 in HNSCC is significantly correlated. Human papillomavirus infection (P16 positive) is negatively related to postoperative recurrence. HNSCC patients with positive PD-L1/PD-1 expression tend to have better overall survival outcomes and lower probability of recurrence, providing more evidence for the PD-l-targeted immunotherapy of HNSCC.

Efficacy and safety of nivolumab in Japanese patients with uterine cervical cancer, uterine corpus cancer, or soft tissue sarcoma: Multicenter, open-label phase 2 trial

Nivolumab is a human monoclonal antibody against the immune checkpoint receptor programmed death‐1, inhibiting binding to programmed death‐ligand 1 or 2 (PD‐L1 or PD‐L2). This phase 2 study evaluated the efficacy and safety of nivolumab in patients with advanced/recurrent uterine cervical cancer, uterine corpus cancer, or soft tissue sarcoma (STS). Patients received nivolumab 240 mg at 2‐week intervals. Primary endpoint was objective response rate; secondary endpoints included overall survival, progression‐free survival, and safety. PD‐L1 expression and microsatellite‐instability (MSI) status were analyzed as potential efficacy biomarkers. Objective response rate was 25%, 23%, and 0% in patients with cervical cancer (n = 20), corpus cancer (n = 22), and STS (n = 21), respectively. The lower 80% confidence intervals of objective response rates in patients with cervical or corpus cancer exceeded the threshold rate (5%); the primary endpoint was met in cervical and corpus cancer, but not in STS. Median progression‐free survival was 5.6, 3.4, and 1.4 months, and 6‐month overall survival was 84%, 73%, and 86% in cervical cancer, corpus cancer, and STS, respectively. The objective response rate was higher in patients with cervical cancer with PD‐L1‐positive (n = 5/15; 33%) versus PD‐L1‐negative (n = 0/5; 0%) tumors. The two patients with corpus cancer classified as MSI‐high responded; the six patients classified as microsatellite stable did not respond. Overall, nivolumab showed acceptable toxicity in all cohorts, with evidence of clinical activity in uterine cervical or corpus cancer, but not in STS. PD‐L1 expression in cervical cancer and MSI‐high in corpus cancer may predict clinical activity of nivolumab in these cancers.