Copy Number Analysis of 9p24.1 in Classic Hodgkin Lymphoma Arising in Immune Deficiency/Dysregulation

A subset of patients with rheumatoid arthritis receiving methotrexate develop immune deficiencies and dysregulation-associated lymphoproliferative disorders. Patients with these disorders often exhibit spontaneous regression after MTX withdrawal; however, chemotherapeutic intervention is frequently required in patients with classic Hodgkin lymphoma arising in immune deficiency/dysregulation. In this study, we examined PD-L1 expression levels and 9p24.1 copy number alterations in 27 patients with classic Hodgkin lymphoma arising from immune deficiency/dysregulation. All patients demonstrated PD-L1 protein expression and harbored 9p24.1 copy number alterations on the tumor cells. When comparing clinicopathological data and associations with 9p24.1 copy number features, the copy gain group showed a significantly higher incidence of extranodal lesions and clinical stages than the amplification group. Notably, all cases in the amplification group had latency type II, while 6/8 (75%) in the copy gain group had latency type II, and 2/8 (25%) had latency type I. Thus, a subset of the copy-gain group demonstrated more extensive extranodal lesions and higher clinical stages. This finding speculates the presence of a genetically distinct subgroup within the group of patients who develop immune deficiencies and dysregulation-associated lymphoproliferative disorders, which may explain certain characteristic features.

KN046, a bispecific antibody against PD-L1 and CTLA-4, plus chemotherapy as first-line treatment for metastatic NSCLC: A multicenter phase 2 trial

KN046, a bispecific antibody targeting PD-L1 and CTLA-4, presents a promising therapeutic option for metastatic non-small cell lung cancer (NSCLC). In this multicenter phase 2 trial, patients with nonsquamous (non-sq) NSCLC receive pemetrexed, whereas those with sq-NSCLC receive paclitaxel, plus KN046 and carboplatin. Following four cycles, maintenance therapy includes KN046 with pemetrexed for non-sq-NSCLC and KN046 for sq-NSCLC. The objective response rate is 46.0%, and the median duration of response is 8.1 months. The median progression-free and overall survival are 5.8 and 26.6 months, respectively. The common adverse events include anemia (87.4%), loss of appetite (72.4%), and neutropenia (70.1%). The most prevalent immune-related adverse event is pruritus (28.7%). These findings indicate that first-line treatment with KN046 and chemotherapy is effective and tolerable in metastatic NSCLC patients, warranting further investigation in a larger phase 3 trial. The trial is registered at ClinicalTrials.gov (NCT04054531).

Immunogenic Bifunctional Nanoparticle Suppresses Programmed Cell Death-Ligand 1 in Cancer and Dendritic Cells to Enhance Adaptive Immunity and Chemo-Immunotherapy

Blockade of programmed cell death-1/programmed cell death-ligand 1 (PD-L1) immune checkpoints with monoclonal antibodies has shown great promise for cancer treatment, but these antibodies can cause immune-related adverse events in normal organs. Here we report a dual-cell targeted chemo-immunotherapeutic nanoscale coordination polymer (NCP), OxPt/BP, comprising oxaliplatin (OxPt) and 2-bromopalmitic acid (BP), for effective downregulation of PD-L1 expression in both cancer cells and dendritic cells (DCs) by inhibiting palmitoyl acyltransferase DHHC3. OxPt/BP efficiently promotes DC maturation by increasing intracellular oxidative stress and enhancing OxPt-induced immunostimulatory immunogenic cancer cell death. Systemic administration of OxPt/BP reduces the growth of subcutaneous and orthotopic colorectal carcinoma by facilitating the infiltration and activation of cytotoxic T lymphocytes together with reducing the population of immunosuppressive regulatory T cells. As a result, OxPt/BP significantly extends mouse survival without causing side effects. This work highlights the potential of NCPs in simultaneously reprogramming cancer cells and DCs for potent cancer treatment.

Endocervical Adenocarcinoma Showing Microcystic, Elongated, and Fragmented (MELF) Pattern of Stromal Invasion: A Single-Institutional Analysis of 10 Cases with Comprehensive Clinicopathological Analyses and Ki-67 Immunostaining

Microcystic, elongated, and fragmented (MELF) pattern of invasion has seldom been documented in endocervical adenocarcinoma (EAC). The aim of this study was to analyze the clinicopathological characteristics of EAC showing MELF pattern. We collected the clinicopathological information of 10 cases of EAC with the MELF pattern and conducted polymer-based immunostaining for Ki-67 (dilution 1:200, clone MIB-1) on these cases. Ki-67 expression was assessed using the average estimation within the hotspot method. All tumors were human papillomavirus-associated EAC with Silva pattern C. All except one tumor exceeded 3 cm in size. Five tumors involved the entire thickness of the cervical stroma, and four tumors extended into the parametrium. Lymphovascular space invasion was identified in six cases. Two patients developed metastatic recurrences in the para-aortic lymph nodes and lungs, respectively. The MELF area showed significantly lower Ki-67 labelling index than that of a conventional tumor area. We confirmed our previous observation that the MELF area displayed lower proliferative activity than the conventional tumor area of EAC. We also demonstrated that patients with EAC showing MELF pattern had several adverse clinicopathological characteristics reflecting aggressive behavior. On the other hand, since the frequencies of post-operative recurrence and disease-related mortality that occurred during the follow-up period were relatively low, further investigations are warranted to clarify the prognostic value of MELF pattern in EAC patients.

PLP2 Could Be a Prognostic Biomarker and Potential Treatment Target in Glioblastoma Multiforme

Objective

This study aimed to discern the association between PLP2 expression, its biological significance, and the extent of immune infiltration in human GBM.

Methods

Utilizing the GEPIA2 and TCGA databases, we contrasted the expression levels of PLP2 in GBM against normal tissue. We utilized GEPIA2 and LinkedOmics for survival analysis, recognized genes co-expressed with PLP2 via cBioPortal and GEPIA2, and implemented GO and KEGG analyses. The STRING database facilitated the construction of protein-protein interaction networks. We evaluated the relationship of PLP2 with tumor immune infiltrates using ssGSEA and the TIMER 2.0 database. An IHC assay assessed PLP2 and PDL-1 expression in GBM tissue, and the Drugbank database aided in identifying potential PLP2-targeting compounds. Molecular docking was accomplished using Autodock Vina 1.2.2.

Results

PLP2 expression was markedly higher in GBM tissues in comparison to normal tissues. High PLP2 expression correlated with a decrease in overall survival across two databases. Functional analyses highlighted a focus of PLP2 functions within leukocyte. Discrepancies in PLP2 expression were evident in immune infiltration, impacting CD4+ T cells, neutrophils, myeloid dendritic cells, and macrophages. There was a concomitant increase in PLP2 and PD-L1 expression in GBM tissues, revealing a link between the two. Molecular docking with ethosuximide and praziquantel yielded scores of -7.441 and -4.295 kcal/mol, correspondingly.

Conclusion

PLP2's upregulation in GBM may adversely influence the lifespan of GBM patients. The involvement of PLP2 in pathways linked to leukocyte function is suggested. The positive correlation between PLP2 and PD-L1 could provide insights into PLP2's role in glioma modulation. Our research hints at PLP2's potential as a therapeutic target for GBM, with ethosuximide and praziquantel emerging as potential treatment candidates, especially emphasizing the potential of these compounds in GBM treatment targeting PLP2.

Metastasis and immunosuppression promoted by mtDNA and PD-L1 in extracellular vesicles are reversed by WGP β-glucan in oral squamous cell carcinoma

The suppressive regulatory T cells (Treg) are frequently upregulated in cancer patients. This study aims to demonstrate the hypothesis that arecoline could induce the secretion of mitochondrial (mt) DNA D-loop and programmed cell death-ligand 1 (PD-L1) in extracellular vesicles (EVs), and attenuate T-cell immunity by upregulated Treg cell numbers. However, the immunosuppression could be reversed by whole glucan particle (WGP) β-glucan in oral squamous cell (OSCC) patients. Arecoline-induced reactive oxygen specimen (ROS) production and cytosolic mtDNA D-loop were analyzed in OSCC cell lines. mtDNA D-loop, PD-L1, IFN-γ, and Treg cells were also identified for the surgical specimens and sera of 60 OSCC patients. We demonstrated that higher mtDNA D-loop, PD-L1, and Treg cell numbers were significantly correlated with larger tumor size, nodal metastasis, advanced clinical stage, and areca quid chewing. Furthermore, multivariate analysis confirmed that higher mtDNA D-loop levels and Treg cell numbers were unfavorable independent factors for survival. Arecoline significantly induced cytosolic mtDNA D-loop leakage and PD-L1 expression, which were packaged by EVs to promote immunosuppressive Treg cell numbers. However, WGP β-glucan could elevate CD4+ and CD8+ T-cell numbers, mitigate Treg cell numbers, and promote oral cancer cell apoptosis. To sum up, arecoline induces EV production carrying mtDNA D-loop and PD-L1, and in turn elicits immune suppression. However, WGP β-glucan potentially enhances dual effects on T-cell immunity and cell apoptosis and we highly recommend its integration with targeted and immune therapies against OSCC.

Association of PD-L1 tumor proportion score ≥20% with early resistance to osimertinib in patients with EGFR-mutated NSCLC

BACKGROUND

The relationship between epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) resistance, including osimertinib, and programmed cell death-ligand 1 (PD-L1) expression status in EGFR-mutated non-small cell lung carcinoma (NSCLC) remains unclear.

PATIENTS AND METHODS

We retrospectively analyzed 64 patients with unresectable advanced or metastatic NSCLC carrying EGFR exon 19 deletions (ex19del) or EGFR exon 21 L858R substitutions (L858R) who received osimertinib as the first-line treatment. We compared progression-free survival (PFS) between eligible patients with PD-L1 tumor proportion scores (TPS) ≥20% and PD-L1 TPS <20% using the Kaplan-Meier survival plots with a log-rank test. Multivariate analysis was performed to examine the poor prognostic factors of PFS.

RESULTS

The PD-L1 TPS ≥20% group included 22 cases (median [range] age: 70.5 [33-86] years; 10 women [45.5%]; 11 current or ex-smokers [50%]); ECOG performance status (PS) of 0-1/2/3/4 was noted in 16/4/1/1 patients, respectively. The PD-L1 TPS <20% group included 42 patients (median [range] age 73 [43-88] years; 29 women [69%]; 12 current or ex-smokers [28.6%]); ECOG PS of 0-1/2/3/4 was noted in 33/6/3/0 cases, respectively. The median PFS was 9.1 and 28.1 months in the PD-L1 TPS ≥20% and PD-L1 TPS <20% groups, respectively (log-rank p = 0.013). Multivariate analysis revealed that PD-L1 TPS ≥20% was associated with PFS (hazard ratio: 2.35, 95% confidence interval: 1.09-5.08, p = 0.030).

CONCLUSION

PD-L1 TPS ≥20% in patients with EGFR-mutated NSCLC may be associated with early resistance to osimertinib.

PD-L1 Expression is Linked to Tumor-Infiltrating T-Cell Exhaustion and Adverse Pathological Behavior in Pheochromocytoma/Paraganglioma

Pheochromocytoma/paraganglioma (PPGL) is an endocrine-related tumor associated with excessive catecholamine release and has limited treatment options once metastasis occurs. Although recent phase 2 clinical trials of immune checkpoint inhibitors in the treatment of PPGL have preliminarily shown promising results, the fundamentals of immunotherapy for PPGL have not yet been established. In the early research, using bulk RNA sequencing of tumor samples from 7 PPGL patients, we found that PPGL tumor tissues exhibited high PD-L1 mRNA expression compared with adjacent normal adrenal medulla tissues, and this was related to T-cell exhaustion biomarkers. To further validate the association, in this study (n = 60), we first stratified all PPGL samples according to PD-L1 expression as determined by immunohistochemical staining, and then subjected 23 fresh PPGL tumor samples from the cohort to a quantitative polymerase chain reaction (n = 16), flow cytometry (n = 7), and multiplex-immunofluorescence staining. Subsequently, we evaluated the pathological manifestations of all 60 PPGL tumor samples and analyzed the correlation among PD-L1 expression, adverse pathological behavior, various clinicopathological data, and genotypes in PPGL. The results showed that PD-L1-positive expression correlated with the exhaustion of tumor-infiltrating T cells, preoperative abnormal elevation of plasma norepinephrine, high Ki67 index, and adverse pathological behavior in PPGL but not with genetic mutation or metastatic disease, possibly due to the limitation of the small number of patients with metastatic disease (n = 4) in the study cohort. In conclusion, our findings reveal that PD-L1 expression is associated with T-cell exhaustion and adverse pathological behavior in PPGL. These results are expected to provide a new theoretical basis and clinical guidance for the treatment of PPGL.

Biomarkers for Predicting Response to Personalized Immunotherapy in Gastric Cancer

Despite advances in diagnostic imaging, surgical techniques, and systemic therapy, gastric cancer (GC) is the third leading cause of cancer-related death worldwide. Unfortunately, molecular heterogeneity and, consequently, acquired resistance in GC are the major causes of failure in the development of biomarker-guided targeted therapies. However, by showing promising survival benefits in some studies, the recent emergence of immunotherapy in GC has had a significant impact on treatment-selectable procedures. Immune checkpoint inhibitors (ICIs), widely indicated in the treatment of several malignancies, target inhibitory receptors on T lymphocytes, including the programmed cell death protein (PD-1)/programmed death-ligand 1 (PD-L1) axis and cytotoxic T-lymphocyte-associated protein 4 (CTLA4), and release effector T-cells from negative feedback signals. In this article, we review currently available predictive biomarkers (including PD-L1, microsatellite instability, Epstein-Barr virus, and tumor mutational burden) that affect the ICI treatment response, focusing on PD-L1 expression. We further briefly describe other potential biomarkers or mechanisms for predicting the response to ICIs in GC. This review may facilitate the expansion of the understanding of biomarkers for predicting the response to ICIs and help select the appropriate therapeutic approaches for patients with GC.

Mesonephric-like Adenocarcinoma of the Uterine Corpus: Genomic and Immunohistochemical Profiling with Comprehensive Clinicopathological Analysis of 17 Consecutive Cases from a Single Institution

Data on genetic and immunophenotypical characteristics of uterine mesonephric-like adenocarcinoma (MLA) remain limited. Therefore, we aimed to investigate the clinicopathological, immunohistochemical, and molecular features of uterine MLA. We performed targeted sequencing, array comparative genomic hybridization, and immunostaining in 17, 13, and 17 uterine MLA cases, respectively. Nine patients developed lung metastases. Eleven patients experienced disease recurrences. The most frequently mutated gene was Kirsten rat sarcoma viral oncogene homolog (KRAS; 13/17). Both the primary and matched metastatic tumors harbored identical KRAS (3/4) and phosphatase and tensin homolog deleted on chromosome 10 (1/4) mutations, and did not harbor any additional mutations. A total of 2 of the 17 cases harbored tumor protein 53 (TP53) frameshift insertion and deletion, respectively. Chromosomal gains were detected in 1q (13/13), 10 (13/13), 20 (10/13), 2 (9/13), and 12 (6/13). Programmed cell death-ligand 1 overexpression or mismatch repair deficiency was not observed in any of the cases. Initial serosal extension and lung metastasis independently predicted recurrence-free survival with hazard ratios of 6.30 and 7.31, respectively. Our observations consolidated the clinicopathological and molecular characteristics of uterine MLA. Both clinicians and pathologists should consider these features to make an accurate diagnosis of uterine MLA and to ensure appropriate therapeutic management of this rare entity.

Radionecrosis mimicking pseudo‑progression in a patient with lung cancer and brain metastasis following the combination of anti‑PD‑1 therapy and stereotactic radiosurgery: A case report

Brain metastases (BMs) usually develop in patients with non-small cell lung cancer. In addition to systemic therapy, radiation therapy and surgery, anti-programmed cell death-ligand 1 (PD-L1) therapy is another promising clinical anticancer treatment modality. However, the optimal timing and drug-drug interactions of anti-PD-L1 therapy with other combined treatments remain to be elucidated. Treatment with anti-PD-L1 therapy is associated with an increased risk of radionecrosis (RN) regardless of tumor histology. The present study described a case of RN in a patient with lung adenocarcinoma and with BM who received anti-PD-L1 therapy. Before anti-PD-L1 treatment, the patient received whole brain radiotherapy. During durvalumab treatment, the intracranial metastases regressed. The progression of intracranial lesions 9 months later prompted a second-line of therapy with PD-L1 inhibitor durvalumab and stereotactic radiotherapy (SRT). Despite stereotactic irradiation, the lesions progressed further, leading to surgical resection. On examination, RN was detected, but there was no evidence of metastatic lung cancer. The aim of the present study was to present the longitudinal change in magnetic resonance imaging in RN following STR and anti-PD-L1 combined therapy. The atypical image of RN is conditionally important for making an accurate preoperative diagnosis.

Rationale and design of phase II clinical trial of dual inhibition with ramucirumab and erlotinib in EGFR exon 19 deletion-positive treatment-naïve non-small cell lung cancer with high PD-L1 expression (SPIRAL-3D study)

Background

Osimertinib is a standard treatment option for epidermal growth factor receptor (EGFR) mutation-positive non-small cell lung cancer (NSCLC). However, osimertinib monotherapy yields poor clinical outcomes in some patients, necessitating the development of novel treatment strategies. In addition, several studies have suggested that high programmed cell death-ligand 1 (PD-L1) expression is associated with poor progression-free survival (PFS) for osimertinib monotherapy in patients with advanced NSCLC harboring EGFR mutations.

Objective

To evaluate the clinical efficacy of erlotinib plus ramucirumab for EGFR exon 19 deletion-positive treatment-naïve NSCLC with high PD-L1 expression.

Design

A single-arm, prospective, open-label, phase II study.

Methods and Analysis

Patients with treatment-naïve EGFR exon 19 deletion-positive NSCLC with high PD-L1 expression and a performance status of 0-2 will receive combination therapy with erlotinib plus ramucirumab until evidence of disease progression or development of unacceptable toxicity. High PD-L1 expression is defined as a tumor proportion score of 50% or higher, as determined by PD-L1 immunohistochemistry 22C3 pharmDx testing. The Kaplan-Meier method and the Brookmeyer and Crowley method with the arcsine square-root transformation will be used with PFS as the primary endpoint. The secondary endpoints include overall response rate, disease control rate, overall survival, and safety. A total of 25 patients will be enrolled.

Ethics

The study has been approved by the Clinical Research Review Board, Kyoto Prefectural University of Medicine, Kyoto, Japan, and written informed consent will be obtained from all patients.

Discussion

To the best of our knowledge, this is the first clinical trial to focus on PD-L1 expression in EGFR mutation-positive NSCLC. If the primary end point is met, combination therapy with erlotinib and ramucirumab could become a potential treatment option for this clinical population.

Trial Registration

This trial was registered with the Japan Registry for Clinical Trials on 12 January 2023 (jRCTs 051220149).

A Three-in-One Nanoscale Coordination Polymer for Potent Chemo-Immunotherapy

The addition of immune checkpoint blockade to standard chemotherapy has changed the standards of care for some cancer patients. However, current chemo-immunotherapy strategies do not benefit most colorectal cancer patients and many triple-negative breast cancer patients. Here, the design of a three-in-one nanoscale coordination polymer (NCP), OX/GC/CQ, comprising prodrugs of oxaliplatin (OX), gemcitabine (GC), and 5-carboxy-8-hydroxyquinoline (CQ) for triple-modality chemo-immunotherapy is reported. OX/GC/CQ exhibits optimal pharmacokinetics and enhanced particle accumulation and drug release in acidic tumor tissues, wherein CQ greatly enhances immunogenic cell death induced by OX/GC and downregulates programmed cell death-ligand 1  expression in cancer cells. Consequently, OX/GC/CQ efficiently promotes infiltration and activity of cytotoxic T lymphocytes, while decreasing the proportion of immunosuppressive regulatory T cells. Intravenous injection of OX/GC/CQ reduces the growth of colorectal carcinoma and triple-negative breast cancer, prevents metastasis to lungs, and extends mouse survival by 30-40 days compared to free drugs. This work highlights the potential of NCPs in co-delivering synergistic chemo-immunotherapeutics for the treatment of advanced and aggressive cancers.

Case report: Advanced primary squamous cell carcinoma in the periampullary area with upregulation of programmed cell death-ligand 1 expression and response to sintilimab immunotherapy

Primary squamous cell carcinoma (SCC) of the periampullary area is exceedingly rare. We report a case of a 45-year-old woman who presented with progressive upper abdominal pain and melena. Laboratory testing revealed an elevated level of carcinoembryonic antigen. Esophagogastroduodenoscopy revealed a very large irregular ulcerated tumor in the periampullary area. Contrast-enhanced computed tomography (CT) of the chest, abdomen, and pelvis, 18 F-fluorodeoxyglucose positron emission tomography/CT, and thin-prep cytologic test excluded metastasis of the primary tumor to the periampullary area from other sites. Immunohistochemistry revealed positive p40 and cytokeratin (CK)5/6, indicating SCC. The expression of programmed cell death-ligand 1 (PD-L1) in tumor cells was upregulated, and the patient responded well to chemotherapy combined with immunotherapy. To the best of our knowledge, this is the first reported case of advanced primary SCC in the periampullary area with high expression of PD-L1.

Interleukin-3-Receptor-α in Triple-Negative Breast Cancer (TNBC): An Additional Novel Biomarker of TNBC Aggressiveness and a Therapeutic Target

Simple Summary

Molecular and histological profiling is crucial for biomarker and therapeutic target discovery, for example, in TNBC. We demonstrated that IL-3Rα expression led to the identification of a subgroup of TNBC patients displaying a poor overall survival. Moreover, we refined TNBC molecular annotation and drew a model including IL-3Rα, PD-L1, and genes related to EMT, which finely discriminates cancer aggressiveness. Finally, we first demonstrated that IL-3Rα is instrumental in granting tumour adaptation and progression by reprogramming TNBC cells to form large dysfunctional vessels and reshaping PD-L1 expression in primary tumours and metastases. Therefore, the IL-3/IL-3Rα axis may be proposed as a marker of TNBC aggressiveness, as a novel TNBC therapeutic challenge.

Abstract

Tumour molecular annotation is mandatory for biomarker discovery and personalised approaches, particularly in triple-negative breast cancer (TNBC) lacking effective treatment options. In this study, the interleukin-3 receptor α (IL-3Rα) was investigated as a prognostic biomarker and therapeutic target in TNBC. IL-3Rα expression and patients’ clinical and pathological features were retrospectively analysed in 421 TNBC patients. IL-3Rα was expressed in 69% human TNBC samples, and its expression was associated with nodal metastases (p = 0.026) and poor overall survival (hazard ratio = 1.50; 95% CI = 1.01–2.2; p = 0.04). The bioinformatics analysis on the Breast Invasive Carcinoma dataset of The Cancer Genome Atlas (TCGA) proved that IL-3Rα was highly expressed in TNBC compared with luminal breast cancers (p = 0.017, padj = 0.026). Functional studies demonstrated that IL-3Rα activation induced epithelial-to-endothelial and epithelial-to-mesenchymal transition, promoted large blood lacunae and lung metastasis formation, and increased programmed-cell death ligand-1 (PD-L1) in primary tumours and metastases. Based on the TCGA data, IL-3Rα, PD-L1, and EMT coding genes were proposed to discriminate against TNBC aggressiveness (AUC = 0.86 95% CI = 0.82–0.89). Overall, this study identified IL-3Rα as an additional novel biomarker of TNBC aggressiveness and provided the rationale to further investigate its relevance as a therapeutic target.

Everolimus (RAD001) combined with programmed death-1 (PD-1) blockade enhances radiosensitivity of cervical cancer and programmed death-ligand 1 (PD-L1) expression by blocking the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR)/S6 kinase 1 (S6K1) pathway

Cervical cancer (CC) is the 4^th most prevalent malignancy in females. This study explored the mechanism of everolimus (RAD001) combined with programmed death-1 (PD-1) blockade on radiosensitivity by phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway and autophagy in CC cells. Low-radiosensitive CaSki cells were selected as study objects. After RAD001 treatment, PI3K/AKT/mTOR pathway activation, autophagy, migration and invasion abilities, autophagy-related proteins (LC3-I, LC3-II, and p62), and PD-L1 expression in CC cells were detected. After triple treatment of radiotherapy (RT), RAD001, and PD-1 blockade to the CC mouse models, tumor weight and volume were recorded. Ki67 expression, the number of CD8 + T cells, and the ability to produce IFN-γ and TNF-α in tumor tissues were determined. RAD001 promoted autophagy by repressing PI3K/AKT/mTOR pathway, augmented RT-induced apoptosis, and weakened migration and invasion, thereby increasing CC cell radiosensitivity. RAD001 elevated RT-induced PD-L1 level. RT combined with RAD001 and PD-1 blockade intensified the inhibitory effect of RT on tumor growth, reduced the amount of Ki67-positive cells, enhanced radiosensitivity of CC mice, and increased the quantity and killing ability of CD8 + T cells. Briefly, RAD001 combined with PD-1 blockade increases radiosensitivity of CC by impeding the PI3K/AKT/mTOR pathway and potentiating cell autophagy.

Cancer Immunotherapy: An Overview on Small Molecules as Inhibitors of the Immune Checkpoint PD-1/PD-L1 (2015-2021)

In 2018, James Allison and Tasuku Honjo received the Nobel Prize in Physiology or Medicine for their discovery of tumor therapy inhibition of negative immune regulation. Immunotherapy stimulates T-cells to fight cancer cells by blocking different immune checkpoint pathways. The interaction between programmed cell death 1 (PD-1) and its ligand PD-L1 (Programmed cell death ligand 1), is one of the main immune checkpoints. Of note, interfering with this pathway is already exploited in clinical cancer therapy, demonstrating that it is one of the key factors involved in cancer immune escape. The development of monoclonal antibodies (mAbs) that possess the ability to inhibit the interactions between PD-1/PD-L1 has radically made the difference in cancer immunotherapy. Yet, because of the many drawbacks that this therapy possesses, the research moved its efforts towards the development of novel small molecules. This may constitute a hope, but also an arduous challenge in fighting cancer. This paper reviews the recent primary literature concerning the development of novel small molecules able to blockade the interaction between PD-1 and its ligand PD-L1.

Prognostic significance of volume-based 18F-FDG PET/CT parameters and correlation with PD-L1 expression in patients with surgically resected lung adenocarcinoma

The aim of this study was to retrospectively analyze 18F-FDG positron emission tomography/computed tomography (18F-FDG PET/CT) metabolic variables, programmed death-ligand 1 (PD-L1) and phosphorylated signal transducer and activator of transcription 3 (p-STAT3) tumor expression, and other factors as predictors of disease-free survival (DFS) in patients with lung adenocarcinoma (LUAD) (stage IA-IIIA) who underwent surgical resection. We still lack predictor of immune checkpoint (programmed cell death-1 [PD-1]/PD-L1) inhibitors. Herein, we investigated the correlation between metabolic parameters from 18F-FDG PET/CT and PD-L1 expression in patients with surgically resected LUAD.Seventy-four patients who underwent 18F-FDG PET/CT prior to treatment were consecutively enrolled. The main 18F-FDG PET/CT-derived variables were primary tumor maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG). Surgical tumor specimens were analyzed for PD-L1 and p-STAT3 expression using immunohistochemistry. Correlations between immunohistochemistry results and 18F-FDG PET/CT-derived variables were compared. Associations of PD-L1 and p-STAT3 tumor expression, 18F-FDG PET/CT-derived variables, and other factors with DFS in resected LUAD were evaluated.All tumors were FDG-avid. The cutoff values of low and high SUVmax, MTV, and TLG were 12.60, 14.87, and 90.85, respectively. The results indicated that TNM stage, PD-L1 positivity, and high 18F-FDG PET/CT metabolic volume parameters (TLG ≥90.85 or MTV ≥14.87) were independent predictors of worse DFS in resected LUAD. No 18F-FDG metabolic parameters associated with PD-L1 expression were observed (chi-square test), but we found that patients with positive PD-L1 expression have significantly higher SUVmax (P = .01), MTV (P = .00), and TLG (P = .00) than patients with negative PD-L1 expression.18F-FDG PET/CT metabolic volume parameters (TLG ≥90.85 or MTV ≥14.87) were more helpful in prognostication than the conventional parameter (SUVmax), PD-L1 expression was an independent predictor of DFS in patients with resected LUAD. Metabolic parameters on 18F-FDG PET/CT have a potential role for 18F-FDG PET/CT in selecting candidate LUAD for treatment with checkpoint inhibitors.

High PD-L1 Expression on Tumor Cells Indicates Worse Overall Survival in Advanced Oral Squamous Cell Carcinomas of the Tongue and the Floor of the Mouth but Not in Other Oral Compartments

The markers of the tumor microenvironment (TME) are promising prognostic and predictive factors in oral squamous cell carcinoma (OSCC). The current study aims to analyze the immunohistochemical expression of programmed cell death-ligand 1 (PD-L1) and interleukin-33 (IL-33) in a cohort of 95 chemonaïve OSCCs. PD-L1 and IL-33 were assessed separately in tumor cells (TCs) and tumor-infiltrating lymphocytes (TILs). High PD-L1 expression in TILs was associated with better overall survival (OS) in univariate analysis. Tumors localized in the floor of the oral cavity and tongue tended to have a lower percentage of PD-L1-positive TCs when compared to other locations. PD-L1 expression on TCs had no prognostic significance when the whole cohort was analyzed. However, along with the T descriptor (TNM 8th), it was included in the multivariable model predicting death in carcinomas of the floor of the oral cavity and tongue (HR = 2.51, 95% CI = 1.97-5.28). In other locations, only nodal status was identified as an independent prognostic factor in multivariate analysis (HR = 0.24, 95% CI = 0.08-0.70). Expression of IL-33 had no impact on survival, but it was differently expressed in various locations. In conclusion, the prognostic significance of PD-L1 in oral cancer depends on the tumor site and type of cell expressing immune checkpoint receptor (TCs vs. TILs).

Prognostic significance of programmed cell death-ligand 1 expression on circulating tumor cells in various cancers: A systematic review and meta-analysis

Background

The prognostic significance of programmed cell death‐ligand 1 (PD‐L1) expression on circulating tumor cells (CTCs) has been explored but is still in controversy. We performed, for the first time, a meta‐analysis to systematically evaluate its prognostic value in human cancers.

Methods

Literature databases were searched for eligible studies prior to June 30, 2021. The pooled hazard ratios (HRs) and 95% confidence intervals (95% CIs) were calculated for the associations of pre‐treatment and post‐treatment PD‐L1⁺ CTCs with progression‐free survival (PFS) and overall survival (OS). Subgroup analyses with regards to cancer type, treatment, CTC enrichment method, PD‐L1 detection method, cut‐off, and specifically the comparison model were performed.

Results

We included 30 eligible studies (32 cohorts, 1419 cancer patients) in our analysis. Pre‐treatment PD‐L1⁺ CTCs detected by immunofluorescence (IF) tended to predict better PFS (HR = 0.55, 95% CI 0.28–1.08, p = 0.084) and OS (HR = 0.61, 95% CI 0.36–1.04, p = 0.067) for immune checkpoint inhibitor (ICI) treatment, but were significantly associated with unfavorable survival for non‐ICI therapies (PFS: HR = 1.85, 95% CI 1.21–2.85, p = 0.005; OS: HR = 2.44, 95% CI 1.69–3.51, p < 0.001). Post‐treatment PD‐L1⁺ CTCs predicted markedly worse PFS and OS. The prognostic value was obviously modulated by comparison models. Among patients with detectable CTCs, PD‐L1⁺ individuals had comparable survival to PD‐L1⁻ individuals, except ICI treatment for which PD‐L1⁺ may predict better PFS (HR = 0.42, 95% CI 0.17–1.06, p = 0.067). Patients with PD‐L1⁺ CTCs had worse survival prognosis compared to those without PD‐L1⁺ CTCs in overall analysis (PFS: HR = 2.10, 95% CI 1.59–2.77, p < 0.001; OS: HR = 2.55, 95% CI 1.70–3.81, p < 0.001) and in most subgroups.

Conclusions

Our analysis demonstrated that PD‐L1 positive expression on CTCs predicted better survival prognosis for ICI treatment but worse survival for other therapies, which thus can be potentially used as a prognostic marker of malignant tumor treatment. However, the prognostic value of PD‐L1⁺ CTCs for ICI treatment needs validation by more large‐scale studies in the future.

False-negative programmed death-ligand 1 immunostaining in ethanol-fixed endobronchial ultrasound-guided transbronchial needle aspiration specimens of non-small-cell lung cancer patients

Aims

Programmed death‐ligand 1 (PD‐L1) immunostaining is used to predict which non‐small‐cell lung cancer (NSCLC) patients will respond best to treatment with programmed cell death protein 1/PD‐L1 inhibitors. PD‐L1 immunostaining is sometimes performed on alcohol‐fixed cytological specimens instead of on formalin‐fixed paraffin‐embedded (FFPE) biopsies or resections. We studied whether ethanol prefixation of clots from endobronchial ultrasound‐guided transbronchial needle aspiration (EBUS‐TBNA) results in diminished PD‐L1 immunostaining as compared with formalin fixation.

Methods and results

FFPE cell blocks from EBUS‐TBNA specimens of 54 NSCLC patients were identified. For each case, paired samples were available, consisting of clots directly immersed in formalin and clots prefixed in Fixcyt (50% ethanol). Serial sections were immunostained for PD‐L1 by use of the standardised SP263 assay and the 22C3 antibody as a laboratory‐developed test (LDT). PD‐L1 positivity was determined with two cut‐offs (1% and 50%). Concordance of PD‐L1 positivity between the formalin‐fixed (gold standard) and ethanol‐prefixed material was assessed. When the 22C3 LDT was used, 30% and 36% of the ethanol‐prefixed specimens showed false‐negative results at the 1% and 50% cut‐offs, respectively (kappa 0.64 and 0.68). When SP263 was used, 22% of the ethanol‐prefixed specimens showed false‐negative results at the 1% cut‐off (kappa 0.67). At the 50% cut‐off, concordance was higher (kappa 0.91), with 12% of the ethanol‐prefixed specimens showing false‐negative results.

Conclusion

Ethanol fixation of EBUS‐TBNA specimens prior to formalin fixation can result in a considerable number of false‐negative PD‐L1 immunostaining results when a 1% cut‐off is used and immunostaining is performed with SP263 or the 22C3 LDT. The same applies to use of the 50% cut‐off when immunostaining is performed with the 22C3 LDT.

Nocardia Rubra Cell Wall Skeleton Up-Regulates T Cell Subsets and Inhibits PD-1/PD-L1 Pathway to Promote Local Immune Status of Patients With High-Risk Human Papillomavirus Infection and Cervical Intraepithelial Neoplasia

The Nocardia rubra cell wall skeleton (Nr-CWS) for external use is an immune enhancer, which has been widely used in human cervix diseases such as cervical erosion, but the mechanism of Nr-CWS enhancing immunity is still unclear. The purpose of this study was to explore the effect and mechanism of Nr-CWS on the local immune status of cervical tissue in patients with high-risk human papillomavirus (HR-HPV) infection and cervical precancerous lesion, cervical intraepithelial neoplasia (CIN). The recruited patients with HR-HPV infection and CIN were treated with Nr-CWS. The specimens were taken from these patients before and after local application of Nr-CWS respectively. The normal control specimens were tested simultaneously. Serial section analysis of immunohistochemistry and co-expression analysis were performed to characterize populations of T cells and the expressions of programmed cell death-1 (PD-1) and programmed cell death-ligand 1 (PD-L1). The levels of cytokines in local cervical tissue were also detected. Nr-CWS significantly increased T cells including CD4⁺, CD8⁺ T cells, and reduced the expression of PD-L1 in the patients’ local cervical tissues. Co-expression analyses showed that the proportions of PD-1⁺CD4⁺ cells in CD4⁺ T cells and PD-1⁺CD8⁺ cells in CD8⁺ T cells decreased after Nr-CWS application. Furthermore, the increase in the number of immune cells was accompanied by increased pro-inflammatory cytokines interleukin-12 (IL-12), interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), and decreased suppressive cytokine IL-10. The results indicate that Nr-CWS, as an immunotherapeutic agent for HR-HPV infection and CIN, plays an immune promoting role related to the upregulation of T cell subsets and the inhibition of PD-1/PD-L1 pathway.

Immune checkpoint inhibitor-associated hypercalcaemia

Immune checkpoint inhibitors (CPIs) have recently become a cornerstone for the treatment of different advanced cancers. These drugs have the ability to reactivate the immune system against tumour cells but can also trigger a myriad of side effects, termed immune-related adverse events (irAEs). Although there are numerous reports of CPI-related endocrinopathies, hypercalcaemia as a suspected irAE is not well documented. The mechanisms of CPI hypercalcaemia are not clearly established. However, in our review, four distinct causes emerged: endocrine disease-related, sarcoid-like granuloma, humoral hypercalcaemia due to parathyroid-related hormone and hyperprogressive disease following CPI initiation. Prompt recognition of hypercalcaemia and the institution of therapy can be lifesaving, affording the opportunity to address the underlying aetiology. In this review we discuss the incidence, diagnosis and management of immune-related hypercalcaemia in oncological patients receiving CPI agents.

PD-L1 Expression in Muscle-Invasive Urinary Bladder Urothelial Carcinoma According to Basal/Squamous-Like Phenotype

Urothelial carcinoma (UC) is the most common histologic type of urinary bladder cancer, and muscle-invasive UC shows aggressive behaviors. Programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) blockades have been approved as standard treatments for patients with advanced stage UC. A total of 166 muscle-invasive urinary bladder cancer (MIBC) patients, who underwent transurethral resection of the bladder or cystectomy from 2004 to 2010 were included. We evaluated PD-L1 expression by the SP142 and SP263 assays and classified the cases “positive” or “negative” according to the manufacturer’s recommendations. We performed immunohistochemistry (IHC) for cytokeratin (CK) 5/6, CK14, GATA3, FOXA1, and CK20 and classified samples as Basal-Squamous-like (BASQ) or non-BASQ subtype. The overall concordance rate for PD-L1 expression is 91.6% (152/166) (kappa = 0.732). The SP142 assay showed 15.1% positivity; the SP263 assay showed 23.5%. The high positivity in the SP142 and SP263 assay was significantly correlated with positive CK5/6, CK14 expression, negative GATA3, FOXA1, and CK20 expression. Classification according to IHC expression resulted in 12.0% (20/166) of samples being classified as BASQ subtype and 88.0% (146/166) of samples being classified as non-BASQ subtype. High positivity in the SP142 and SP263 assay was significantly correlated with the BASQ subtype (p < 0.001, both). Our study is the first to analyze the association of immunohistochemically defined BASQ and non-BASQ subtypes with two PD-L1 assays in MIBC. In conclusion, we revealed that a high PD-L1 positive rate in all PD-L1 assays was significantly associated with the BASQ-subtype, and these results suggest that the BASQ classification may be important to apply the PD-1/PD-L1 blockades in MIBC.

Formalin fixation for optimal concordance of programmed death-ligand 1 immunostaining between cytologic and histologic specimens from patients with non-small cell lung cancer

BACKGROUND

Immunohistochemical staining of programmed death-ligand 1 (PD-L1) is used to determine which patients with non-small cell lung cancer (NSCLC) may benefit most from immunotherapy. Therapeutic management of many patients with NSCLC is based on cytology instead of histology. In this study, concordance of PD-L1 immunostaining between cytology cell blocks and their histologic counterparts was analyzed. Furthermore, the effect of various fixatives and fixation times on PD-L1 immunoreactivity was studied.

METHODS

Paired histologic and cytologic samples from 67 patients with NSCLC were collected by performing fine-needle aspiration on pneumonectomy/lobectomy specimens. Formalin-fixed, agar-based or CytoLyt/PreservCyt-fixed Cellient cell blocks were prepared. Sections from cell blocks and tissue blocks were stained with SP263 (standardized assay) and 22C3 (laboratory-developed test) antibodies. PD-L1 scores were compared between histology and cytology. In addition, immunostaining was compared between PD-L1-expressing human cell lines fixed in various fixatives at increasing increments in fixation duration.

RESULTS

Agar cell blocks and tissue blocks showed substantial agreement (κ = 0.70 and κ = 0.67, respectively), whereas fair-to-moderate agreement was found between Cellient cell blocks and histology (κ = 0.28 and κ = 0.49, respectively). Cell lines fixed in various alcohol-based fixatives showed less PD-L1 immunoreactivity compared with those fixed in formalin. In contrast to SP263, additional formalin fixation after alcohol fixation resulted in preserved staining intensity using the 22C3 laboratory-developed test and the 22C3 pharmDx assay.

CONCLUSIONS

Performing PD-L1 staining on cytologic specimens fixed in alcohol-based fixatives could result in false-negative immunostaining results, whereas fixation in formalin leads to higher and more histology-concordant PD-L1 immunostaining. The deleterious effect of alcohol fixation could be reversed to some degree by postfixation in formalin.

PD-L1 protein expression and copy number gains in HIV-positive locally advanced cervical cancer

Background:

The programmed death-1/programmed death-ligand-1 (PD-1/PD-L1) axis may represent a target for cervical cancer; however, it is poorly understood in human immunodeficiency virus (HIV)-infected patients.

Methods:

We evaluated HIV-positive (n = 42) and HIV-negative (n = 110) women with locally advanced cervical cancer regarding their PD-L1 expression, determined by combined positive score (CPS) ⩾ 1 and tumor proportion score (TPS) ⩾ 25%, and PD-L1 copy number alterations, assessed by fluorescence in situ hybridization.

Results:

Regardless of HIV status, 84.9% and 44.8% of cases were PD-L1-positive according to CPS ⩾ 1 and TPS ⩾ 25%. Per CPS ⩾ 1, PD-L1 positive rate was similar between HIV-positive and HIV-negative women, whereas a significant difference was seen per TPS ⩾ 25%. Tumor size and parametrial invasion were correlated with PD-L1 positivity in HIV-negative women, whereas anti-retroviral therapy (ART) was correlated with TPS < 25%. Low CD4-positive cell counts were associated with CPS < 1 in HIV-positive women. No significant difference was observed in PD-L1 copy number status between HIV-positive and HIV-negative women. PD-L1 amplification and polysomy were independently associated with TPS ⩾ 25%, whereas the presence of parametrial invasion was independently associated with CPS ⩾ 1. Cancer stage and PD-L1 amplification were identified as independent predictors of recurrence-free survival [hazard ratio (HR) = 2.40 (1.32–4.36) and HR = 5.33 (1.94–14.61)] and cancer-specific survival [HR = 13.62 (5.1–36.38) and HR = 3.53 (1.43–8.69)]. PD-L1 polysomy was an independent predictor of locoregional recurrence-free survival [HR = 3.27 (1.27–8.41)]. HIV status and PD-L1 expression (CPS ⩾ 1 or TPS ⩾ 25%) were not associated with poor patient outcomes.

Conclusion:

PD-L1 amplification and polysomy are the strongest drivers of PD-L1 expression in cervical cancer, and could represent prognostic biomarkers for anti-PD-1/PD-L1 therapy. Cervical cancer biology may be modulated by HIV infection, CD4-positive cells, and HIV treatments.

Programmed Cell Death-Ligand 1 Expression Status in Urothelial Carcinoma According to Clinical and Pathological Factors: A Multi-Institutional Retrospective Study

Purpose: To investigate programmed cell death-ligand 1 (PD-L1) expression status and the clinical and pathological factors related to its expression in urothelial carcinoma (UC) patients.

Materials and Methods: Data from 761 UC patients who underwent testing for PD-L1 expression using the VENTANA (SP-142 immunohistochemistry assay) for measuring PD-L1 expression according to the manufacturer's protocol between February 2016 and July 2019 were retrospectively reviewed. Patients were categorized into three groups based on the percentage of tumor area covered by PD-L1-expressing tumor-infiltrating immune cells (ICs) as follows: IC0 (<1%), IC1 (≥1% and <5%), and IC2/3 (≥5%). Positive PD-L1 expression was defined as IC2/3 (≥5%). The factors related to positive PD-L1 expression were assessed by using unadjusted and adjusted logistic regression analyses.

Results: In the entire cohort, 213 (28%) patients showed positive PD-L1 expression. Final adjusted regression analyses for positive PD-L1 expression revealed that several factors, including intravesical BCG prior to PD-L1 testing (odds ratio [OR] 0.57, 95% confidence interval [CI] 0.37–0.96), advanced tumor stage (stage III/IV) (OR 2.04, 95% CI 1.41–2.93), and high tumor grade (OR 5.31, 95% CI 2.38–11.83) were significantly associated with positive PD-L1 expression.

Conclusions: This study showed that the PD-L1 expression is associated with several clinical and pathological factors for the first time in a real-world setting. Further follow-up clinical trials should consider adjusting these factors, including intravesical BCG treatment, tumor stage and grade to clarify the utility of PD-L1 as a biomarker.

Epithelial-to-mesenchymal transition and its association with PD-L1 and CD8 in thyroid cancer

Programmed cell death-ligand 1 (PD-L1) has recently been shown to play a role in the regulation of epithelial-to-mesenchymal transition (EMT); however, the relationship between PD-L1 expression, EMT and the inflammatory tumour microenvironment has yet to be investigated in thyroid cancer. To address this issue, we examined the expression of CD8, PD-L1 and the EMT markers E-cadherin and vimentin in a cohort of 74 papillary thyroid cancer (PTC) patients and investigated the association of these with clinicopathologic characteristics and disease-free survival (DFS). The relationship between PD-L1 and EMT was further examined in three thyroid cancer cell lines via Western blot and live cell imaging. In order to expand our in vitro findings, the normalised gene expression profiles of 516 thyroid cancer patients were retrieved and analysed from The Cancer Genome Atlas (TCGA). PD-L1 positivity was significantly higher in PTC patients exhibiting a mesenchymal phenotype (P = 0.012). Kaplan-Meier analysis revealed that PD-L1 (P = 0.045), CD8 (P = 0.038) and EMT status (P = 0.038) were all significant predictors for DFS. Sub-analysis confirmed that the poorest DFS was evident in PD-L1 positive patients with EMT features and negative CD8 expression (P < 0.0001). IFN-γ treatment induced upregulation of PD-L1 and significantly promoted an EMT phenotype in two thyroid cancer cell lines. Our findings suggest that PD-L1 signalling may play a role in stimulating EMT in thyroid cancer. EMT, CD8 and PD-L1 expression may serve as valuable predictive biomarkers in patients with PTC.

Immune Checkpoint Inhibitors and Cardiac Toxicity in Patients Treated for Non-Small Lung Cancer: A Review

Lung cancer is a major cause of cancer-related mortality worldwide, both in men and women. The vast majority of patients are diagnosed with non-small-cell lung cancer (NSCLC, 80-85% of lung cancer cases). Therapeutics named immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment in the last decade. They are monoclonal antibodies, and those directed against PD-1 (programmed cell death protein 1) or PD-L1 (programmed cell death-ligand 1) have been used in the treatment of lung cancer and significantly improved the prognosis of NSCLC patients. However, during treatment with ICIs, immune-related adverse events (irAEs) can occur in any organ and any tissue. At the same time, although cardiac irAEs are relatively rare compared to irAEs in other organs, they have a high mortality rate. The two most common clinical manifestations of immunotherapy-related cardiotoxicity are myocarditis and pericarditis. Various types of arrhythmias have been reported in patients treated with ICIs, including the occurrence of life-threatening complete atrioventricular block or ventricular tachyarrhythmias. Here, we aim to summarize the incidence, clinical manifestations, underlying mechanisms, diagnosis, and treatment strategies for ICI-associated cardiotoxicity as these issues become very important in view of the increasing use of ICI in the treatment of lung cancer.

Water extract of sporoderm-broken spores of Ganoderma lucidum enhanced pd-l1 antibody efficiency through downregulation and relieved complications of pd-l1 monoclonal antibody

PURPOSE

Osteosarcoma is a malignant musculoskeletal tumor with early metastasis and a poor prognosis, especially in adolescents. Ganoderma lucidum (Leyss. Ex Fr.) Karst (G. lucidum), a traditional East Asian medicine, has been reported to play a critical role in antitumor and immunomodulatory activity. The aim of this study was to investigate the effects and molecular mechanisms of water extract of sporoderm-broken spores of G. lucidum (BSGWE) on osteosarcoma PD-L1 (programmed cell death-ligand 1) transcriptional regulation, efficacy enhancement, and side effect remission.

METHODS

The antitumor effects on cell proliferation of BSGWE in osteosarcoma cells were detected by apoptosis flow cytometry, and the migration ability of HOS and K7M2 cells were evaluated by cell scratch assay. Potential signaling regulation of PD-L1 was detected by western blotting. To confirm the signaling pathway of BSGWE-related PD-L1 downregulation, a pho-STAT3 turnover experiment was carried out. Colivelin was administered as a pho-STAT3 activator to rescue the BSGWE-induced PD-L1 inhibition. To further study in vivo signaling, in a Balb/c osteosarcoma allograft model, tumor volume was measured using an in vivo bioluminescence imaging system. The body weight curve and tumor volume curve were analyzed to reveal the remission effects of BSGWE on PD-L1 antibody-related body weight loss and its immunomodulatory effects on the osteosarcoma and spleen. The PD-L1 expression level and expression of related transcription-factor pho-STAT3 in tumor cells and spleens were assessed by IHC analysis.

RESULTS

BSGWE suppressed the proliferation and migration of osteosarcoma cells in vitro via induction of apoptosis. In addition, BSGWE downregulated PD-L1 expression and related STAT3 (signal transducers and activators of transcription) phosphorylation levels in a dose-dependent manner. Western blotting and qRT-PCR assay revealed that BSGWE downregulated PD-L1 expression by inhibiting STAT3 phosphorylation. A turnover experiment showed that colivelin administration could rescue PD-L1 inhibition via pho-STAT3 activation. BSGWE not only downregulated PD-L1 expression via the STAT3 pathway in an allograft Balb/c mouse model, but also relieved complications including weight loss and spleen atrophy in a mouse monoclonal antibody therapy model on the basis of its traditional advantages in immune enhancement.

CONCLUSION

BSGWE downregulated PD-L1 expression via pho-STAT3 inhibition of protein and RNA levels. BSGWE enhanced PD-L1 antibody efficacy via phosphorylated STAT3 downregulation in vitro and in vivo. BSGWE also relieved complications of weight loss and spleen atrophy in a murine allograft osteosarcoma immune checkpoint blockade therapy model.

Prognostic Role and Clinical Significance of Tumor-Infiltrating Lymphocyte (TIL) and Programmed Death Ligand 1 (PD-L1) Expression in Triple-Negative Breast Cancer (TNBC): A Systematic Review and Meta-Analysis Study

This meta-analysis aimed to evaluate the prognostic value of tumor-infiltrating lymphocytes (TILs) and programmed death-ligand 1 (PD-L1), their associations with the clinicopathological characteristics, and the association between their levels in patients with triple-negative breast cancer (TNBC). PubMed, EMBASE, Scopus, ProQuest, Web of Science, and Cochrane Library databases were searched to obtain the relevant papers. Seven studies with 1152 patients were included in this study. Like the level of TILs, there were no significant associations between PD-L1 expression and tumor size, tumor stage, lymph node metastasis, histological grade, and Ki67 (All p-values ≥ 0.05). Furthermore, there was no significant association between PD-L1 expression with overall survival (OS) and disease-free survival (DFS). In assessment of TILs and survival relationship, the results showed that a high level of TILs was associated with long-term OS (hazard ratios (HR) = 0.48, 95% CI: 0.30 to 0.77, p-value < 0.001) and DFS (HR = 0.53, 95% CI: 0.35 to 0.78, p-value < 0.001). The results displayed that tumoral PD-L1 expression was strongly associated with high levels of TILs in TNBC patients (OR = 8.34, 95% CI: 2.68 to 25.95, p-value < 0.001). In conclusion, the study has shown the prognostic value of TILs and a strong association between tumoral PD-L1 overexpression with TILs in TNBC patients.

Synergistic effect of ibrutinib and CD19 CAR-T cells on Raji cells in vivo and in vitro

Ibrutinib might improve the efficacy of anti‐CD19 chimeric antigen receptor (CD19 CAR) T‐cell therapy in chronic lymphocytic leukemia (CLL). We studied the possibility and mechanism of the synergistic effect of ibrutinib and CAR‐T cells in other types of lymphoma. In this study, we selected the CD19 CAR‐T cells of a patient with lymphoma who failed in his CD19 CAR‐T‐cell therapy and a dose of 8 mg/kg/d ibrutinib. Subcutaneous and tail vein tumorigenic mice were established with Raji cells. The differences in the synergistic effect between these 2 models were compared by bioluminescence imaging (BLI) monitoring and flow cytometry (FCM). The expression of the STAT‐3 signaling pathway was assessed by western blot analysis. There was no synergistic effect of ibrutinib and CD19 CAR‐T cells in vitro. Programmed cell death‐ligand 1 (PD‐L1) was expressed in 0.23 ± 0.06% of Raji cells. In the subcutaneous tumorigenic model, the luciferase signal was reduced significantly in the group receiving ibrutinib combined with CD19 CAR‐T cells. Moreover, the proportion of CD19 CAR‐T cells was higher in the polytherapy group than in the CAR‐T‐cell monotherapy group. However, we did not get an analogous synergistic effect in the tail vein tumorigenic model. STAT‐3 signaling pathway expression in the residual tumor cells did not differ between those with and those without ibrutinib, suggesting that the IL‐10/STAT‐3/PD‐L1 pathway was not involved in the synergistic effect. Therefore, some other mechanism might be a target for ibrutinib. Our results provide evidence for the use of ibrutinib in polytherapy for other types of B‐cell lymphoma.

Frequency and clinicopathologic associations of DNA mismatch repair protein deficiency in ampullary carcinoma: Routine testing is indicated

BACKGROUND

The significance of DNA mismatch repair (MMR) deficiency in ampullary cancers (ACs) has not been established.

METHODS

In total, 127 ACs with invasive carcinomas measuring ≥3 mmthat had adequate tissue were analyzed immunohistochemically.

RESULTS

MMR loss was detected in 18% of ACs (higher than in colorectal cancers). Twelve tumors with MLH1-PMS2 loss were negative for BRAF V600E mutation, suggesting a Lynch syndrome association. MMR-deficient tumors (n = 23), comparedwith MMR-intact tumors (n = 104), showed a striking male predominance (male:female ratio, 4.7). Although the deficient tumors had slightly larger invasion size (2.7 vs 2.1 cm), they also had more expansile growth and less invasiveness, including less perineural invasion, and they ultimately had lower tumor (T) classification and less lymph node metastasis (30% vs 53%; P = .04). More important, patients who had MMR-deficient tumors had better clinical outcomes, with a 5-year overall survival rate of 68% versus 45% (P = .03), which was even more pronounced in those who had higher Tclassification (5-year overall survival, 69% vs 34%; P = .04). MMR deficiencyhad a statistically significant association with medullary phenotype, pushing-border invasion, and tumor-infiltrating immune cells, and it occurred more frequently in ampullary-duodenal type tumors. Programed cell death-ligand 1 (PD-L1) levels analyzed in the 22 MMR-deficient ACs revealed that all medullary carcinomas were positive. Nonmedullary MMR-deficient carcinomas expressed PD-L1 in 33% of tumors cells according to the criteria for a combined positive score ≥1, but all were negative according to the tumor proportion score≥1 method.

CONCLUSIONS

In ACs, MMR deficiency is even more frequent (18%) than in colon cancer and often has a Lynch-suggestive profile, thus routine testing is warranted. Male gender, pushing-border infiltration, ampullary-duodenal origin, medullary histology, and tumor-related inflammation have a significantly higher association with MMR deficiency. MMR-deficient tumors have less aggressive behavior. PD-L1 expression is common in medullary-phenotype ACs, thus immunotherapy should be considered at least for this group.

Research progress in immune checkpoint inhibitors in the treatment of oncogenedriven advanced nonsmall cell lung cancer

The clinical application of immune checkpoint inhibitors (ICIs) lead to dramatic changes in the treatment strategy for patients with advanced non-small cell lung cancer (NSCLC), but the efficacy of ICIs in oncogene-driven NSCLC is controversial. Existing research shows that the efficacy of ICIs may be related to different types of driver genes, programmed cell death-ligand 1 (PD-L1) level, and tumor mutational burden (TMB). It may involved in other factors, such as clinical characteristics, and immune cell density. ICIs monotherapy or combination therapy may play a role in a subset of oncogene-driven NSCLC patients, but further studies are needed to select these patients, which may be an important direction for the future development of advanced NSCLC.

Comparability of PD-L1 immunohistochemistry assays for non-small-cell lung cancer: a systematic review

Programmed cell death ligand 1 (PD‐L1) immunohistochemistry is used to determine which patients with advanced non‐small‐cell lung cancer (NSCLC) respond best to treatment with PD‐L1 inhibitors. For each inhibitor, a unique immunohistochemical assay was developed. This systematic review gives an up‐to‐date insight into the comparability of standardised immunohistochemical assays and laboratory‐developed tests (LDTs), focusing specifically on tumour cell (TC) staining and scoring. A systematic search was performed identifying publications that assessed interassay, interobserver and/or interlaboratory concordance of PD‐L1 assays and LDTs in tissue of NSCLC patients. Of 4294 publications identified through the systematic search, 27 fulfilled the inclusion criteria and were of sufficient methodological quality. Studies assessing interassay concordance found high agreement between assays 22C3, 28‐8 and SP263 and properly validated LDTs, and lower concordance for comparisons involving SP142. A decrease in concordance, however, is seen with use of cut‐offs, which hampers interchangeability of PD‐L1 immunohistochemistry assays and LDTs. Studies assessing interobserver concordance found high agreement for all assays and LDTs, but lower agreement with use of a 1% cut‐off. This may be problematic in clinical practice, as discordance between pathologists at this cut‐off may result in some patients being denied valuable treatment options. Finally, five studies assessed interlaboratory concordance and found moderate to high agreement levels for various assays and LDTs. However, to assess the actual existence of interlaboratory variation in PD‐L1 testing and PD‐L1 positivity in clinical practice, studies using real‐world clinical pathology data are needed.

Treatment outcomes of patients with adenocarcinoma of the uterine cervix after definitive radiotherapy and the prognostic impact of tumor-infiltrating CD8+ lymphocytes in pre-treatment biopsy specimens: a multi-institutional retrospective study

The current study aimed to evaluate the outcomes of patients with adenocarcinoma (AC) of the uterine cervix after definitive radiotherapy (RT) and to evaluate prognostic factors, including immunity-related molecules. A total of 71 patients with AC of the uterine cervix from multiple Japanese institutions were retrospectively analysed. Histological subtypes were diagnosed according to the 2014 World Health Organization classification. All patients underwent definitive RT comprising external beam RT and intracavitary brachytherapy with or without concurrent chemotherapy. Immunohistochemical studies were performed to detect the expression of programmed cell death-ligand 1(PD-L1) and CD8. The 5-year locoregional control (LC), overall survival (OS) and progression-free survival (PFS) rates for all patients were 61.8, 49.7 and 36.1%, respectively. The LC, OS and PFS rates were not significantly different among the histological subtypes. Membranous PD-L1 expression was not significantly associated with prognosis. Patients with CD8-positive tumor-infiltrating lymphocytes (CD8+TILs) in the tumor nests had significantly better OS than patients without CD8+TILs in the tumor nests (5-year OS: 53.8 vs 23.8%, P = 0.038). As expected, the International Federation of Gynecology and Obstetrics (FIGO) stage (2008) III-IVA and maximum tumor diameter > 40 mm were significantly associated with worse prognosis. In summary, the presence of CD8+TILs in the tumor nests has the potential to be an independent favorable prognostic factor for patients with AC of the uterine cervix after definitive RT.

Refractory solitary cervical lymph node metastasis after esophageal squamous cell carcinoma surgery and its successful treatment with immune checkpoint inhibitor: A case report and literature review

RATIONALE

Although the early detection and treatment of non-metastatic esophageal cancer has improved, these patients' prognoses are still poor. Most patients with radical treatment for esophageal cancer will relapse in 3 years, and the best treatment strategy after recurrence has not been uniformly accepted. Multiform treatments may be beneficial to recurrent patients.

PATIENT CONCERNS

A 60-year-old male patient, due to routinely health examination, ulcerated lesions 30 cm away from the incisors were found by gastroscopy, pathology showed esophageal squamous cell carcinoma (ESCC).

DIAGNOSIS

Due to the patient's pathology, he was diagnosed with ESCC.

INTERVENTIONS

The patient underwent radical surgery for ESCC on June 28, 2015. The left cervical lymph node metastasis occurred after 20 months, and lymph node metastasis carcinoma resection was performed. After that, concurrent chemoradiotherapy was implemented, 40 days after the end of the 4 courses of chemotherapy, the left cervical metastatic lymph nodes relapsed, radioactive particle implantation was carried out, and progressed again after 1 month. The patient took apatinib for 1 week but could not tolerate due to hand-foot syndrome. Immune checkpoint inhibitor (ICI) was administered since October 27, 2017.

OUTCOMES

The therapeutic effect of immune checkpoint inhibitor was evaluated as partial response (PR) after 6 courses of treatment and complete response (CR) after 15 courses of treatment. To our knowledge, this is the first case report of successful immunotherapy for refractory esophageal squamous cell carcinoma.

LESSONS

The emergence of ICIs promotes the treatment of esophageal cancer to a new era. Our observations suggest that patients for whom schedule to receive anti-programmed cell death protein-1 (anti-PD-1)/programmed cell death-ligand 1 (PD-L1) immunotherapy may require genomic testing to predict whether tumors respond to ICIs. In this case, we also present the predictors for the efficacy of targeted immunotherapy. At present, no matter which predictor of PD-L1 expression, tumor mutational burden (TMB), microsatellite instability (MSI), and tumor-infiltrating lymphocyte (TIL), a single predictor may be unconvincing and cannot accurately estimate the efficacy of immunotherapy. Multiplex detecting methods and combined biomarkers may provide new strategies. Consensus need to be reached in order to be widely applied in future studies.

C-Myc regulates PD-L1 expression in esophageal squamous cell carcinoma

Immunotherapy using antibodies blocking the programmed cell death 1 (PD-1)/programmed cell death-ligand 1 (PD-L1) pathway has achieved great success in preclinical models and the clinical treatment of esophageal squamous cell carcinoma (ESCC). The c-Myc proto-oncogene helps prevent immune cells from attacking tumor cells by inducing PD-L1 expression. However, the underlying mechanisms of c-Myc and PD-L1 in ESCC remain unclear, and a thorough understanding of this regulation would allow the development of new approaches to enhance antitumor immunity. In the present study, the positive relationship between c-Myc and PD-L1 was explored in the Cancer Genome Atlas dataset using the bioinformatics tool GEPIA, and was confirmed in 105 ESCC tissues by immunostaining (r=0.516, P<0.001). The patients positive for both proteins had a poorer overall survival (P=0.032). Furthermore, in ESCC cell lines, c-Myc overexpression, depletion, and inhibition was able to regulate the expression of PD-L1. Also, the ChIP assays showed that the increase in PD-L1 expression was likely due to the binding of c-Myc to the PD-L1 promoter. Taken together, c-Myc and PD-L1 levels were significantly correlated, and c-Myc expression regulated the expression of PD-L1 in ESCC cells. In addition, a small molecule inhibitor of c-Myc effectively regulated PD-L1 expression. This indicates that synergistic therapy combining a c-Myc inhibitor with PD-L1 immunotherapy might be a promising new treatment strategy for ESCC.

PD-1/PD-L1-dependent immune response in colorectal cancer

Colorectal cancer (CRC) is still considered as the third most frequent cancer in the world. Microsatellite instability (MSI), inflammation, and microRNAs have been demonstrated as the main contributing factors in CRC. Subtype 1 CRC is defined by NK cells infiltration, induction of Th1 lymphocyte and cytotoxic T cell responses as well as upregulation of immune checkpoint proteins including programmed cell death-1 (PD-1). Based on the diverse features of CRC, such as the stage and localization of the tumor, several treatment approaches are available. However, the efficiency of these treatments may be decreased due to the development of diverse resistance mechanisms. It has been proven that monoclonal antibodies (mAbs) can increase the effectiveness of CRC treatments. Nowadays, several mAbs including nivolumab and pembrolizumab have been approved for the treatment of CRC. Immune checkpoint receptors including PD-1 can be inhibited by these antibodies. Combination therapy gives an opportunity for advanced treatment for CRC patients. In this review, an update has been provided on the molecular mechanisms involved in MSI colorectal cancer immune microenvironment by focusing on PD-ligand 1 (PD-L1) and treatment of patients with advanced immunotherapy, which were examined in the different clinical trial phases. Considering induced expression of PD-L1 by conventional chemotherapeutics, we have summarized the role of PD-L1 in CRC, the chemotherapy effects on the PD-1/PD-L1 axis and novel combined approaches to enhance immunotherapy of CRC by focusing on PD-L1.

Correlation of programmed death-ligand 1 expression with gene expression and clinicopathological parameters in Indian patients with non-small cell lung cancer

Objectives:

The aim of this study is to evaluate the incidence of programmed cell death-ligand 1 (PD-L1) expression in non-small cell lung cancer (NSCLC) cases and its correlation with gene mutation and clinicopathological parameters.

Methods:

Samples from NSCLCs patients were studied for PD-L1 expression through immunohistochemistry (IHC) using Rabbit anti-human PDL-1/CD274 Monoclonal Antibody. Genetic mutations were studied using IHC/fluorescence in situ hybridization (FISH) methods (for anaplastic lymphoma kinase [ALK]) or polymerase chain reaction/gene sequencing analysis (for epidermal growth factor receptor [EGFR]). Pearson's correlation coefficient (r) was used for correlation analysis. PD-L1 expression was analyzed for association with clinicopathological features.

Results:

Of the 101 NSCLC cases, PD-L1 expression was observed in 33.66% (34/101) cases; tumor proportion score of <50%: 67.65% (23/34) and ≥50%: 32.35% (11/34) cases. PD-L1 positivity was seen in; males: 35.5%, females: 28%, smokers: 37.7%, cases with brain metastasis: 20%, cases with pleural effusion: 20.8%, and histopathological evaluation (well-differentiated: 21.42%, moderately-differentiated: 13.79%, poorly-differentiated: 36.11%, and adenosquamous disease: 40.9%). Genetic mutation studies revealed PD-L1 positivity in 18.1% cases with EGFR mutation, 50% of ALK-IHC positive cases, and 33.3% ALK-FISH positive cases. No or very weak correlation (r < 0.3) in PD-L1 expression with gene mutations or clinicopathological parameters was observed.

Conclusions:

The study demonstrated PD-L1 expression in ~ 1/3^rd cases of NSCLC patients. No or very weak correlation was observed for PD-L1 expression with genetic mutations and other parameters studied. The presence of gene mutations in PD-L1 expressed samples suggests further investigation on PD-L1 inhibitors in such patients for decisive treatments.

Nivolumab plus ipilimumab versus pembrolizumab as chemotherapy-free, first-line treatment for PD-L1-positive non-small cell lung cancer

BACKGROUND

Nivolumab plus ipilimumab (N-I) or pembrolizumab (PEM) is associated with survival improvement as chemotherapy-free, first-line treatment for patients with advanced non-small cell lung carcinoma (NSCLC) and positive programmed cell death ligand 1 (PD-L1). However, no direct comparison data exist between these two regimens to inform clinical decisions. Therefore, we performed indirect comparison for N-I versus PEM using frequentist methods.

RESULTS

Three randomized trials (KEYNOTE-024, KEYNOTE-042, and CheckMate 227) involving 2372 patients were included. For patients with tumor PD-L1 level of ≥1%, pooled meta-analyses showed that both N-I and PEM improved overall survival (OS) relative to chemotherapy (N-I: hazard ratio [HR] 0.82, 95% CI 0.69-0.97; PEM: HR 0.81, 95% CI 0.71-0.93); whereas only N-I significantly improved progression-free survival (PFS) (N-I: HR 0.79, 95% CI 0.65-0.96; PEM: HR 1.07, 95% CI 0.94-1.21). Neither N-I nor PEM was associated with improved objective response rate (ORR) compared with chemotherapy (N-I: relative risk [RR] 1.20, 95% CI 0.98-1.46; PEM: RR 1.03, 95% CI 0.86-1.23). Indirect comparisons showed that N-I was associated with longer PFS than PEM (HR 0.77, 95% CI 0.62-0.95). However, N-I was not superior to PEM in terms of OS (HR 0.98, 95% CI 0.77-1.24) and ORR (RR 1.17, 95% CI 0.89-1.52). N-I showed a less favorable toxicity profile relative to PEM (all grade adverse events: RR 1.28, 95% CI 1.17-1.40).

CONCLUSIONS

N-I and PEM provide comparable OS benefit for PD-L1-positive NSCLC. N-I further improves PFS relative to PEM but at meaningful cost of toxicities.

Immune Checkpoint Inhibitor-Associated Cardiotoxicity: Current Understanding on Its Mechanism, Diagnosis and Management

Immune checkpoint inhibitors (ICIs) that target cytotoxic T lymphocyte antigen 4, programmed cell death-1, and PD-ligand 1 have revolutionized cancer treatment, achieving unprecedented efficacy in multiple malignancies. ICIs are increasingly being used in early cancer settings and in combination with various other types of therapies, including targeted therapy, radiotherapy, and chemotherapy. However, despite the excellent therapeutic effect of ICIs, these medications typically result in a broad spectrum of toxicity reactions, termed immune-related adverse events (irAEs). Of all irAEs, cardiotoxicity, uncommon but with high mortality, has not been well recognized. Herein, based on previous published reports and current evidence, we summarize the incidence, diagnosis, clinical manifestations, underlying mechanisms, treatments, and outcomes of ICI-associated cardiotoxicity and discuss possible management strategies. A better understanding of these characteristics is critical to managing patients with ICI-associated cardiotoxicity.

Impact of antiretroviral drugs on PD-L1 expression and copy number gains with clinical outcomes in HIV-positive and -negative locally advanced cervical cancers

Cervical cancer has become a leading cause of death in both HIV-infected and uninfected women. Previous studies have revealed that antiretroviral therapy (ART) possesses anti-human papillomavirus (HPV) and antitumour properties, potentially serving as an anticancer agent and improving functional immunity in HIV-positive individuals. However, to the best of our knowledge, no studies have examined the association between ART and the clinical outcome of patients with pre-existing invasive cervical cancer. The current study analysed 48 HIV-positive and 123 HIV-negative patients with locally advanced stage IB2-IVA cervical cancer between December 2008 and December 2016. Tumours were categorized based on programmed cell death-ligand 1 (PD-L1) immunoreactivity and copy number alterations in the PD-L1 gene, as determined by fluorescence in situ hybridization. The results revealed that ART-treated patients exhibited a lower prevalence of PD-L1 immunopositivity, PD-L1 amplification and polysomy compared with patients that did not receive ART and those that were HIV-negative. Furthermore, ART-treated patients with PD-L1 immunonegativity exhibited an improved recurrence-free survival (RFS) compared with patients that did not receive ART and HIV-negative individuals with PD-L1 immunopositivity (P=0.041 vs. P=0.030). Additionally, ART-exposed patients with PD-L1 disomy demonstrated improved locoregional recurrence-free survival (LRR) when compared with HIV-negative patients with PD-L1 amplification and polysomy (P=0.039 vs. P=0.007), RFS (P<0.001 vs. P=0.006) and cancer-specific survival (CSS) (P=0.021 vs. P=0.025). ART-exposed patients with PD-L1 disomy also exhibited improved RFS (P<0.001) and CSS (P<0.001) compared with HIV-negative patients with PD-L1 amplification. Improved LRRs were demonstrated in ART-exposed patients with PD-L1 disomy (P=0.028) compared with non-HIV patients with polysomy. Following multivariate analysis, International Federation of Gynaecology and Obstetrics stage and PD-L1 amplification were determined to be predictors of poor a RFS [hazard ratio (HR), 2.43; 95% confidence interval (CI), 1.37–4.30; P=0.002 vs. HR, 7.03; 95% CI, 2.79–17.74; P<0.001) and CSS (HR, 11.47; 95% CI, 4.70–27.99; P<0.001 vs. HR, 4.05; 95% CI, 1.64–9.98; P=0.002). However, only PD-L1 polysomy was determined to be a predictor of poor LRR (HR, 2.50; 95% CI, 1.11–5.63; P=0.027). HIV status was not associated with poor outcomes, as determined using Cox models. The results of the current study indicated that ART may be used for the treatment of cervical cancer in both HIV-infected and uninfected patients. However, additional research is required to further elucidate these results.

Expression of programmed cell death-ligand 1 in primary testicular diffuse large B cell lymphoma: A retrospective study

The present study evaluated programmed cell death-ligand 1 (PD-L1) expression in tumor cells and in the tumor microenvironment (TME) and its association with clinical data in primary testicular diffuse large B cell lymphoma (DLBCL). PD-L1 was determined by immunohistochemistry in 30 patients with primary testicular DLBCL and assessed for associations with clinical characteristics, progression-free survival (PFS) and overall survival (OS). The mean patient age was 62.2 years. Overall, 10 (33.3%) patients had advanced-stage (stage III/IV) disease and 14 (46.7%) patients had an International Prognostic Index (IPI) of ≥3. The median follow-up time following orchiectomy was 23.5 months. During this time, 10 (33.3%) patients experienced disease progression and 11 (36.7%) patients succumbed. PD-L1 expression in tumor cells and in the TME was detected in 20 (66.7%) and 13 (43.3%) patients, respectively. PD-L1 expression on tumor cells and in the TME was higher in those at an early stage compared with patients with an advanced stage of disease (P=0.045 and 0.017, respectively). In addition, PD-L1 expression in tumor cells was higher in patients with a low IPI compared with those with a high IPI (P=0.019). A Kaplan-Meier analysis identified no association of PD-L1 expression on tumor cells with PFS (P=0.763) or OS (P=0.531), or of PD-L1 expression in the TME with PFS (P=0.572) or OS (P=0.934). The present study demonstrated that PD-L1 expression in tumor cells and in the TME was higher in patients at an early stage of disease compared with those at an advanced stage, and that PD-L1 expression on tumor cells was higher in patients with a low IPI than in those with a high IPI. Furthermore, PD-L1 expression in tumor cells and in the TME was not associated with PFS or OS.

Efficacy and safety profiles of programmed cell death-1/programmed cell death ligand-1 inhibitors in the treatment of triple-negative breast cancer: A comprehensive systematic review

Triple-negative breast cancer (TNBC) is associated with worse prognosis, with limited treatment regiments available and higher mortality rate. Immune checkpoint inhibitors targeting programmed cell death-1 (PD-1) or programmed cell death-ligand 1 (PD-L1) showed great potentials in treating malignancies and may serve as potential therapies for TNBC. This systematic review aims to evaluate the efficacy and safety profiles of PD-1/PD-L1 inhibitors in the treatment of TNBC. Literature search was performed via PubMed, EBSCOhost, Scopus, and CENTRAL databases, selecting studies which evaluated the use of anti-PD-1/PDL1 for TNBC from inception until February 2019. Risk of bias was assessed by the Newcastle-Ottawa Scale (NOS). Overall, 7 studies evaluating outcomes of 1395 patients with TNBC were included in this systematic review. Anti-PD-1/PD-L1 showed significant antitumor effect, proven by their promising response (objective response rate (ORR), 18.5-39.4%) and survival rates (median overall survival (OS), 9.2-21.3 months). Moreover, anti- PD-1/PD-L1 yielded better outcomes when given as first-line therapy, and overexpression of PD-L1 in tumors showed better therapeutic effects. On the other hands, safety profiles were similar across agents and generally acceptable, with grade ≥3 treatment- related adverse effects (AEs) ranging from 9.5% to 15.6% and no new AEs were experienced by TNBC patients. Most grade ≥3 AEs are immune-mediated, which are manifested as neutropenia, fatigue, peripheral neuropathy, and anemia. PD-1/PD-L1 inhibitors showed promising efficacy and tolerable AEs, and thus may benefit TNBC patients. Further studies of randomized controlled trials with larger populations are needed to better confirm the potential of these agents.

Selective Suppression of Cell Growth and Programmed Cell Death-Ligand 1 Expression in HT1080 Fibrosarcoma Cells by Low Molecular Weight Fucoidan Extract

Low molecular weight fucoidan extract (LMF), prepared by an abalone glycosidase digestion of a crude fucoidan extracted from Cladosiphon novae-caledoniae Kylin, exhibits various biological activities, including anticancer effect. Various cancers express programmed cell death-ligand 1 (PD-L1), which is known to play a significant role in evasion of the host immune surveillance system. PD-L1 is also expressed in many types of normal cells for self-protection. Previous research has revealed that selective inhibition of PD-L1 expressed in cancer cells is critical for successful cancer eradication. In the present study, we analyzed whether LMF could regulate PD-L1 expression in HT1080 fibrosarcoma cells. Our results demonstrated that LMF suppressed PD-L1/PD-L2 expression and the growth of HT1080 cancer cells and had no effect on the growth of normal TIG-1 cells. Thus, LMF differentially regulates PD-L1 expression in normal and cancer cells and could serve as an alternative complementary agent for treatment of cancers with high PD-L1 expression.

Increased nerve twigs in small intestinal mucosa with programmed cell death-ligand 1 and somatostatin receptor type 2A expression in recurrent Crohn disease: A case report

RATIONALE

Inflammatory bowel disease (IBD) patients manifest symptoms of disturbed gut function, such as neural sensory-motor changes. Programmed cell death-ligand 1 (PD-L1), normally present in neural tissue, exists in close apposition to the mucosal immune system and intestinal epithelium, and a bi-directional communication is known to occur at these interfaces. Somatostatin has been shown to suppress the inflammatory reaction, and has been used in several clinical trials to treat inflammatory disorders, such rheumatoid arthritis. Recently, somatostatin receptor type 2A, that regulates neurotransmission, proliferation, and apoptosis, has been recognized in IBD. Although prominent abnormalities in the morphology of the enteric nervous system have been observed in idiopathic IBD, they are more marked in Crohn disease.

PATIENT CONCERNS

A 55-year-old woman with recurrent Crohn disease, just surgically treated for ileal resection, have a stenotic complication.

INTERVENTIONS

At surgery 5 cm of preterminal ileum with stenosis and anastomotic ileocolic block was removed.

DIAGNOSES

The histopathology showed a recurrent Crohn in fistulo-stenotic phase; the stenosis was mainly sustained by mass-forming, ganglioneuromatous hyperplasia. Normally very rare, fine nerve twigs extend up into mucosa but we found a new-formed fibrillary network, extending into the inflammation area at the subepithelial luminal site of the mucosa, that was positive to PD-L1 and somatostatin receptor type 2A (SSTR2A) immunostaining but not visualized in routinary stained slides.

OUTCOMES

After surgery the patient was semestrally followed with clinical endoscopic evaluation that results uneventfully.

LESSONS

Our case shows that before surgery neuromatous abnormalities can be predicted by immunostained new-formed twigs in the mucosa.

Prognostic value of PD-L1 expression in resected lung adenocarcinoma and potential molecular mechanisms

Background: The prognostic role of PD-L1 expression in surgically resected lung adenocarcinoma (ADC) remains controversial. The present study was aimed to clarify the role of PD-L1 expression in predicting prognosis and to investigate its biological function in ADC.

Materials and Methods: The association between PD-L1 expression and clinical outcomes in patients with resected ADC was analyzed using immunohistochemistry (IHC) in our cohort (n=104), externally validated by a meta-analysis of 13 published studies. The biological role of PD-L1 in ADC was explored using gene set enrichment analysis (GSEA).

Results: Positive PD-L1 expression in tumor cells was observed in 38.5% (40/104). High PD-L1 expression levels were significantly correlated with poor overall survival (P=0.008). Furthermore, the meta-analysis also showed that positive PD-L1 expression was associated with shorter OS than negative PD-L1 expression (HR= 1.75, 95% CI: 1.26-2.42; P<0.001). In subgroup analysis stratified according to ethnicity, the pooled results demonstrated that increased PD-L1 expression was an unfavorable prognostic factor for Asian populations (HR= 2.11, 95% CI: 1.48-3.02; P<0.001), but not for non-Asian populations (HR=1.16, 95% CI: 0.63-2.11, P=0.64). The pooled odds ratios (ORs) indicated that PD-L1 expression was associated with positive lymph node metastasis (OR=1.74, 95% CI: 1.23-2.46; P=0.002) and male (OR=1.56, 95% CI: 1.02-2.37; P=0.04). GSEA revealed PD-L1 expression levels positively correlated with immune process or immune-related pathways.

Conclusion: PD-L1 expression is an important negative prognostic factor in resected ADC. This finding has important implications for immunotherapy targeting the PD-1/PD-L1 pathway in patients with resected ADC.

[Small interfering RNA-mediated programmed cell death-ligand 1 silencing in human glioma cells enhances human CD8+ T lymphocyte cytotoxicity in vitro]

OBJECTIVE

To investigate the effect of small interfering RNA (siRNA)-mediated silencing of programmed cell deathligand 1 (PD-L1) in human glioma cells on the cytotoxicity of human CD8⁺T lymphocytes against the modified tumor cells.

METHODS

A siRNA sequence targeting PD-L1 gene was designed and transfected into human glioma U87 MG cells via lipofectamine 2000, and the gene silencing effect was validated using RT-qPCR, Western blotting, and flow cytometry. The transfected cells were co-cultured with human CD8⁺T lymphocytes, and the apoptosis of the tumor cells was analyzed with flow cytometry.

RESULTS

The siRNA sequence showed strong PD-L1 gene-silencing effect at both mRNA and protein levels in U87 MG cells. Compared with the control cells, the transfected U87 MG cells showed significantly increased vulnerability to the cytotoxicity of human CD8⁺T cells and an obvious reduction of proliferative activity in the co-culture (P < 0.05).

CONCLUSIONS

Transfection of human glioma U87 MG cells with the specific siRNA targeting PD-L1 obviously enhances the toxicity of human T lymphocytes in the co-culture.