Programmed Death Ligand Research Articles

CircDDX21 alleviates trophoblast dysfunction and Treg differentiation in recurrent spontaneous abortion via miR-520a-5p/ FOXP3/PD-L1 axis.

Recurrent spontaneous abortion (RSA) is a common complication during pregnancy, which is a burden to patients both physically and mentally. Circular RNAs (circRNAs) play important roles in RSA. However, the roles of circDDX21 in RSA development remain unknown. Decidual samples were harvested from healthy pregnant women and RSA patients. In HTR-8/SVneo and Bewo trophoblast cells, proliferation and migration were analyzed by cell counting kit-8 (CCK-8)/5-ethynyl-2'-deoxyuridine (EdU) staining and transwell/wound healing assays, respectively. CD4+ T cells from peripheral blood mononuclear cells of patients were incubated with trophoblast-conditioned medium. Regulatory T cells (Treg) proliferation was detected by carboxyfluorescein succinimidyl ester (CFSE) assay. Treg proportion, Treg/T helper 17 cells (Th17) ratio, and cytokines were measured using flow cytometry. The association among genes was validated using dual-luciferase assay, RNA immunoprecipitation (RIP), and chromatin immunoprecipitation (ChIP). CircDDX21 and Forkhead box P3 (FOXP3) decreased, while miR-520a-5p increased in the decidual tissues of RSA patients. CircDDX21 overexpression promoted trophoblast proliferation and migration, and facilitated CD4+ T cell differentiation into Treg. CircDDX21 targeted miR-520a-5p to elevate FOXP3. MiR-520a-5p overexpression reversed the promoted trophoblast cell function of circDDX21 overexpression in HTR-8/SVneo cells. FOXP3 overexpression reversed the repressed trophoblast cell function elicited by miR-520a-5p overexpression in HTR-8/SVneo cells. FOXP3 promoted Treg differentiation by transcriptionally upregulating programmed cell death ligand 1 (PD-L1). CircDDX21 ameliorated trophoblast dysfunction and Treg differentiation in RSA via miR-520a-5p/FOXP3/PD-L1 axis.

Triple combination of vemurafenib, cobimetinib, and atezolizumab in real clinical practice in the Russian Federation: results of the A1 cohort of the ISABELLA study.

Among several treatment options for BRAF-mutant metastatic melanoma, a combination of BRAF inhibitor, MEK inhibitor, and anti-PDL1 antibody seems to be a new emergent approach recently registered in the Russian Federation. It is still not clear which patient population benefits more from this simultaneous use of three drugs instead of its sequencing. This study aimed to evaluate patients' characteristics treated in real practice in 14 Russian regions by triple combination and to analyze their outcomes depending on biomarkers (PD-L1 expression). This was a part (cohort A1) of a prospective non-interventional study of clinical outcomes and biomarkers in patients with skin melanoma. Patients were included in cohort A1 if combination treatment with vemurafenib (vem) + cobimetinib (cobi) + atezolizumab (atezo) was initiated no earlier than 12 weeks (84 days) prior to written informed consent to participate in this study. The index event was the initiation of therapy with all three drugs vem + cobi + atezo (i.e., triple combination). The primary efficacy endpoint of the study was the 24-month overall survival (OS), defined as the time from the index date to the date of death from any cause. If the patient did not experience an event, the OS will be censored at the date of the last contact. Objective response rate (ORR), duration of response (DoR), and progression-free survival (PFS) in the Intention to treat (ITT) population, in biomarker positive population, and in population with brain metastases were also evaluated. Quality of life questionnaires were pre-planned by protocol if it was a part of routine practice. Adverse events were also collected. Between March 2021 and May 2023, 59 patients were enrolled in 19 centers from 14 regions of Russia. Thirty-one of 59 (52.4%) patients had central nervous system metastases, and 18 of 31 (58.4%) were symptomatic. Forty of 59 patients (68%) received the triple combination as the first-line treatment. The median follow-up period was 16.83 [95% confidence interval (CI) 13.8-19.8] months. The mean duration of therapy with this regimen was 9.95 months (95% CI 7.48-13.8). ORR was 55.1%; progression as the best outcome was seen in 16.3%. The median DoR was 12.95 months (95% CI 11.0-14.8 months), with a median of 20.3 months (95% CI 9.1-31.5 months) when triple therapy was administered in the first-line treatment. In patients with brain metastases (N = 31), ORR was 45.1%; the median DoR was 12.95 (95% CI 11.0-14.8 months). The median PFS in the entire population was 13.6 months (95% CI 8.6-18.6); the 24-month PFS was 22%. The estimated median OS in the entire population was 15.8 months (95% CI NA); 24-month OS was 45% (95% CI 0.32-0.64). In multivariate Cox regression model, biomarkers of interest [lactate dehydrogenase, Programmed cell death ligand-1 (PD-L1)] did not have statistically significant impact on PFS, OS, or DoR probably due to high data missing rate. No unexpected adverse events were reported. Grades 3-4 AEs were seen in 23 of 59 patients (38%) with most common were skin and liver toxicity. Triple combination of atezolizumab, vemurafenib, and cobimetinib had proven its efficacy and tolerability in real settings. No impact of potential predictive biomarkers was seen (NCT05402059).

Protective Effects of a Dihydrodiazepine Against Endotoxin Shock Through Suppression of TLR4/NF-κB/IRF3 Signaling Pathways.

Sepsis and septic shock are life-threatening systemic inflammatory conditions and among the most frequent causes of morbidity and mortality globally. Preclinical evidence has identified a number of diazepine-based compounds with therapeutic potential in inflammatory diseases. However, the potential anti-inflammatory properties of diazepines in the overwhelming immune response during sepsis have been rarely examined. Thus, the current study aimed to identify a new diazepine compound with therapeutic potential in sepsis. Assessing the inflammatory response of macrophages to Lipopolysaccharides (LPS) in vitro identified 2-[7-(trifluoromethyl)-2,3-dihydro-1H-1,4-diazepin-5-yl]phenol (2-TDDP) as a potential anti-inflammatory agent. It reduced secretion of Interleukin-1β (IL-1β), IL-6, IL-12p70, IL-18, Tumor necrosis factor-α (TNF-α), Interferon-γ (IFN-γ), IFN-β, and increased the secretion of IL-10. In a mouse model of LPS-induced endotoxin shock, 2-TDDP reduced mortality and attenuated inflammation-induced tissue injury in the spleen, liver, kidney, and lung. This was accompanied by reduced serum levels of IL-1β, IL-6, IL-12p70, TNF-α, IFN-γ, IFN-β, and increased levels of IL-10. Importantly, 2-TDDP suppressed the Toll-like receptor 4 (TLR4)/Nuclear factor-κB (NF-κB) and TLR4/Interferon regulatory factor 3 (IRF3) signaling pathways through a reduction in the expression of TLR4, Myeloid differentiation primary response 88 (MyD88), P65, and TNF receptor-associated factor 3 (Traf3). Moreover, 2-TDDP suppressed the expression of CD86, Programmed death-ligand 1 (PD-L1) and C5a receptor (C5aR), but not Major histocompatibility complex II (MHCII). Analysis of splenic lymphocyte populations revealed a decrease in the number of CD4+, CD8+, and B cells. Collectively, these findings introduced the dihydrodiazepine 2-TDDP as a new anti-inflammatory agent with potent therapeutic potential in endotoxin shock, paving an avenue for future clinical application.

Two‐Step Targeting‐Tunable Semiconducting Nanoswitches Amplify Mitochondrion Damage and PD‐L1 Blockade for Orthotopic Pancreatic Cancer Therapy

AbstractPancreatic cancer is a malignancy tumor with luxuriant extracellular matrix (ECM) and highly immunosuppressive microenvironment and its therapy remains an enormous challenge. A two‐step targeting‐tunable strategy is proposed for orthotopic pancreatic cancer therapy via designing semiconducting nanoswitches (C/SPNT/αP) to amplify the mitochondrion damage and programmed death ligand 1 (PD‐L1) blockade. A mitochondrion‐targeting small nanoparticle (SPNT) consisting of mitochondrial targeting moiety triphenylphosphine (TPP) and semiconducting polymer is embedded with PD‐L1 antibody (αPD‐L1) into sono‐responsive collagen binding peptide (CBP)‐conjugated nanoliposomes to form C/SPNT/αP. In the first targeting step, C/SPNT/αP achieve ECM targeting to observably increase their enrichment into orthotopic pancreatic tumor sites because CBP can effectively bind to collagen in ECM. Upon ultrasound (US) irradiation, C/SPNT/αP mediate a sono‐responsive structural failure via sonodynamic effect for on‐demand releases of SPNT and αPD‐L1. In the second targeting step, SPNT target to mitochondria to induce mitochondrial damage under US irradiation for triggering amplified cell apoptosis and immunogenic cell death (ICD). Moreover, the released αPD‐L1 blocks the immunosuppressive pathway to further boost immunological effect. Such a novel therapeutic regimen can almost completely eradicate orthotopic pancreatic Panc02 and KPC tumors in mouse models. This study presents the first two‐step targeting‐tunable nanomedicine for treatments of deep‐seated orthotopic tumors.

Efficacy and safety of immunotherapy combined with chemotherapy in patients with ES-SCLC: A systematic review and network meta-analysis of RCTs and RWSs.

To evaluate the efficacy and safety of programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) inhibitors in the treatment of extensive-stage small-cell lung cancer (ES-SCLC), we conducted a systematic review and meta-analysis that included randomized controlled trials (RCTs) and real-world studies (RWS). By scanning PubMed, Web of science, Embase, and other relevant clinical information public databases, nine RCTs and eight RWSs involving 5205 patients were included in the study. We directly compared the differences between chemotherapy and PD-1/PD-L1 inhibitors plus chemotherapy, and determined the optimal treatment strategy through network meta-analysis (NMA). Compared to chemotherapy, the addition of PD-1/PD-L1 inhibitors significantly improves the overall survival (OS), progression-free survival (PFS), and objective response rate (ORR) in SCLC patients. Regarding safety, both RCTs and RWSs indicated no significant difference in grade 3-4 adverse events between chemotherapy and chemoimmunotherapy. NMA showed serplulimab plus chemotherapy (Serp_Chemo) appears to provide the best OS, PFS, and ORR benefit, while nivolumab plus chemotherapy shows higher toxicity than other regimens. In subgroup analysis, for elderly patients (age ≥65) and non-elderly (age <65) patients, the most promising quality regimens for achieving better OS extension are atezolizumab plus chemotherapy (Atez_Chemo) and Serp_Chemo, respectively. For patients with PD-L1 ≥ 1% and lactate dehydrogenase (LDH) > upper limit of normal (ULN), there is no apparent OS benefit from immune therapy. In ES-SCLC treatment, adding PD-1/PD-L1 inhibitors to standard chemotherapy improves OS, PFS, and ORR, with Serp_Chemo shows the most promise. Atez_Chemo and Serp_Chemo provided better survival for elderly and non-elderly patients, respectively.

IFN-γ primes bone marrow neutrophils to acquire regulatory functions in severe viral respiratory infections.

Neutrophil subsets endowed with regulatory/suppressive properties are widely regarded as deleterious immune cells that can jeopardize antitumoral response and/or antimicrobial resistance. Here, we describe a sizeable fraction of neutrophils characterized by the expression of programmed death-ligand 1 (PD-L1) in biological fluids of humans and mice with severe viral respiratory infections (VRI). Biological and transcriptomic approaches indicated that VRI-driven PD-L1+ neutrophils are endowed with potent regulatory functions and reduced classical antimicrobial properties, as compared to their PD-L1- counterpart. VRI-induced regulatory PD-L1+ neutrophils were generated remotely in the bone marrow in an IFN-γ-dependent manner and were quickly mobilized into the inflamed lungs where they fulfilled their maturation. Neutrophil depletion and PD-L1 blockade during experimental VRI resulted in higher mortality, increased local inflammation, and reduced expression of resolving factors. These findings suggest that PD-L1+ neutrophils are important players in disease tolerance by mitigating local inflammation during severe VRI and that they may constitute relevant targets for future immune interventions.

Influence of Donor-Specific Characteristics on Cytokine Responses in H3N2 Influenza A Virus Infection: New Insights from an Ex Vivo Model.

Influenza A virus (IAV) is known for causing seasonal epidemics ranging from flu to more severe outcomes like pneumonia, cytokine storms, and acute respiratory distress syndrome. The innate immune response and inflammasome activation play pivotal roles in sensing, preventing, and clearing the infection, as well as in the potential exacerbation of disease progression. This study examines the complex relationships between donor-specific characteristics and cytokine responses during H3N2 IAV infection using an ex vivo model. At 24 h post infection in 31 human lung explant tissue samples, key cytokines such as interleukin (IL)-6, IL-10, tumor necrosis factor-alpha (TNF-α), and interferon-gamma (IFN-γ) were upregulated. Interestingly, a history of lung cancer did not impact the acute immune response. However, cigarette smoking and programmed death-ligand 1 (PD-L1) expression on macrophages significantly increased IL-2 levels. Conversely, age inversely affected IL-4 levels, and diabetes mellitus negatively influenced IL-6 levels. Additionally, both diabetes mellitus and programmed cell death protein 1 (PD-1) expression on CD3+/CD4+ T cells negatively impacted TNF-α levels, while body mass index was inversely associated with IFN-γ production. Toll-like receptor 2 (TLR2) expression emerged as crucial in mediating acute innate and adaptive immune responses. These findings highlight the intricate interplay between individual physiological traits and immune responses during influenza infection, underscoring the importance of tailored and personalized approaches in IAV treatment and prevention.

Prognostic value of soluble programmed death-1 and soluble programmed death ligand-1 in severe traumatic brain injury patients

Patients with traumatic brain injury (TBI) frequently exhibit concomitant immunosuppression. In this study, we evaluated the predictive values of soluble programmed death-1 (sPD-1) and soluble programmed death ligand-1 (sPD-L1) in patients with severe TBI. Peripheral blood sPD-1 and sPD-L1 levels were measured within 48 h of patient admission. A total of 20 healthy volunteers and 82 patients were enrolled in this study. The levels of sPD-1 and sPD-L1 were upregulated in patients with severe TBI (P < 0.001). They were significantly increased in the post-TBI severe pneumonia group and among non-survivors (P < 0.001). The area under the curves (AUCs) for sPD-1 and sPD-L1 levels to predict severe pneumonia were 0.714 and 0.696, respectively, and the AUCs to predict mortality were 0.758 and 0.735. The levels of sPD-1 and sPD-L1 are correlated with the GCS scores at admission, APACHE II scores, length of MV, and time elapsed to mortality. The levels of sPD-1 and sPD-L1 emerged as independent predictive factors for severe pneumonia and mortality. This study demonstrates that upregulation of sPD-1 and sPD-L1 in severe TBI patients is significantly associated with severe pneumonia and mortality, suggesting their potential as predictive biomarkers for these outcomes.

Discovery of Benzo[d]oxazoles as Novel Dual Small-Molecule Inhibitors Targeting PD-1/PD-L1 and VISTA Pathway.

The blockers of programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) pathway have achieved great clinical success. However, the limited efficacy and low tumor response rate of anti-PD-1/PD-L1 monotherapy limit the clinical application of PD-1/PD-L1 inhibitors. V-domain immunoglobulin suppressor of T-cell activation (VISTA), a novel checkpoint regulator, exhibits potential synergy with PD-1/PD-L1 in enhancing antitumor immunity. Herein, we report the discovery of benzo[d]oxazole B3 as novel dual small-molecule inhibitors targeting PD-1/PD-L1 and VISTA with high PD-1/PD-L1 inhibitory activity and VISTA binding affinity. B3 rescues the immunosuppression of T-cells mediated by PD-L1 and VISTA and activates antitumor immunity effectively. Moreover, B3 could induce degradation of PD-L1 and VISTA in tumor cell. Furthermore, B3 displays significant in vivo antitumor efficacy in a CT26 mouse model. Our results discover B3 as a promising dual PD-1/PD-L1 and VISTA inhibitor, providing a novel therapeutic strategy to overcome the limitations of current anti-PD-1/PD-L1 therapy.

The Clinicopathological and Prognostic Significance of the Expression of PD-L1 and MET Genes in Breast Cancer: Potential Therapeutic Targets.

The heterogeneity of breast cancer requires exploring novel prognostic biomarkers as well as therapeutic targets for the treatment of the disease. The METABRIC dataset was used to describe the gene expression of the programmed death-ligand 1 (PD-L1) and the hepatocyte growth factor receptor (MET) and their association with the tumor clinicopathologic characteristics and overall survival in breast cancer. The expression of the PD-L1 and MET genes correlated positively with the Nottingham Prognostic Index (NPI) (p=0.003 and p < 0.001, respectively). The expression of the two genes correlated inversely with luminal A and luminal B tumors (r= - 0.089, p= 0.021 and r= - 0.116, p= 0.013, respectively). The PD-L1 mRNA levels were significantly higher in hormone receptor-negative and HER2-positive tumors. MET mRNA expression levels were significantly higher in hormone receptor-negative, HER2-enriched, and non-luminal breast cancers. The PD-L1/MET double-high expression was associated with younger age of patients at diagnosis, higher NPI scores, larger tumors, advanced stage, high-grade, hormone receptor-negativity, HER2-positivity, and non-luminal tumors. None of the genes or their double expression status was significantly associated with overall survival in this analysis. The expression of the PD-L1 and MET genes is remarkably associated with worse tumor clinicopathologic features and poor prognosis in patients with breast cancer. Further investigations using combination drug regimens targeting PD-L1 and MET are important, particularly in breast tumors expressing high levels of both proteins.

Comprehensive population pharmacokinetic modelling of sugemalimab, an anti-programmed death-ligand 1 (PD-L1) human monoclonal antibody, in patients with solid tumours or lymphomas across multiple Phase I-III studies.

The aim of this study was to develop a population pharmacokinetics model for sugemalimab, a monoclonal antibody that targets programmed death-ligand 1 (PD-L1), using data from Phase I-III trials and to assess clinical factors affecting sugemalimab exposure. A nonlinear mixed-effect modelling approach was employed to analyse pooled data from nine studies involving 1628 subjects to characterize the PopPK of sugemalimab. This investigation examined the influence of various covariates on sugemalimab pharmacokinetics (PK), encompassing demographics, baseline hepatic and renal function-related covariates, and others (including anti-drug antibody [ADA], combination treatment, Eastern Cooperative Oncology Group [ECOG] performance score, tumour burden and tumour type). Estimation accuracy and predictive ability of the final model were evaluated using various methods. The influence of covariates on sugemalimab exposure was assessed by simulation from the final model. A two-compartment model with first-order elimination and time-varying clearance effectively described the PK of sugemalimab. Covariate analyses revealed significant relationships between sugemalimab clearance and body weight, albumin, gender, ADA, tumour burden and tumour type. The statistically significant covariates on central volume were body weight, albumin, gender and tumour type. No significant relationships were found in the final model for age, race, alanine aminotransferase, aspartate aminotransferase, creatinine, total bilirubin, alkaline phosphatase, combination treatment, creatinine clearance, ECOG, renal function or hepatic function. All significant covariates demonstrated less than a 20% effect on sugemalimab exposure. The PopPK model adequately described the pharmacokinetic profile of sugemalimab with no clinically meaningful impact observed on its exposure across all covariates. Dose adjustment does not appear to be necessary.

Biomimetic polymeric nanoreactors with photooxidation-initiated therapies and reinvigoration of antigen-dependent and antigen-free immunity

Immune cell-mediated anticancer modalities usually suffer from immune cell exhaustion and limited efficacy in solid tumors. Herein, the oxygen-carrying biomimetic nanoreactors (BNR2(O2)) have been developed with photooxidation-driven therapies and antigen-dependent/antigen-free immune reinvigoration against xenograft tumors. The BNR2(O2) composes polymeric nanoreactors camouflaged with cancer cell membranes can efficiently target homotypic tumors. It continuously releases O2 to boost intracellular reactive oxygen species (ROS) to oxide diselenide bonds, which controllably releases seleninic acids and anti-folate Pemetrexed compared to hydrogen peroxide and glutathione incubation. The O2-rich microenvironment sensitizes Pemetrexed and blocks programmed cell-death ligand 1 (PD-L1) to reverse T cell immunosuppression. The ROS and Pemetrexed upregulate pro-apoptosis proteins and inhibit folate-related enzymes, which cause significant apoptosis and immunogenic cell death to stimulate dendritic cell maturation for improved secretion of cytokines, expanding antigen-dependent T cell immunity. Furthermore, by regulating the release of seleninic acids, the checkpoint receptor human leukocyte antigen E of tumor cells can be blocked to reinvigorate antigen-free natural killer cell immunity. This work offers an advanced antitumor strategy by bridging biomimetic nanoreactors and modulation of multiple immune cells.

PD-L1+ Lymphocytes Are Associated with CD4+, Foxp3+CD4+, IL17+CD4+ T Cells and Subtypes of Macrophages in Resected Early-Stage Non-Small Cell Lung Cancer.

The non-canonical PD-L1 pathway revealed that programmed-death ligand 1 (PD-L1) expression in immune cells also plays a crucial role in immune response. Moreover, immune cell distribution in a tumour microenvironment (TME) is pivotal for tumour genesis. However, the results remain controversial and further research is needed. Distribution of PD-L1-positive (PD-L1+) tumour-infiltrating lymphocytes in the context of TME was assessed in 72 archival I-III stage surgically resected NSCLC tumour specimens. Predominant PD-L1+ lymphocyte distribution in the tumour stroma, compared to islets, was found (p = 0.01). Higher PD-L1+ lymphocyte infiltration was detected in smokers due to their predominance in the stroma. High PD-L1+ lymphocyte infiltration in tumour stroma was more common in tumours with higher CD4+ T cell infiltration in islets and stroma, Foxp3+CD4+ T cell infiltration in islets and lover M1 macrophage infiltration in the stroma (p = 0.034, p = 0.034, p = 0.005 and p = 0.034 respectively). Meanwhile, high PD-L1+ lymphocyte infiltration in islets was predominantly found in tumours with high levels of IL-17A+CD4+ T cells in islets and Foxp3+CD4+ T cells in islets and stroma (p = 0.032, p = 0.009 and p = 0.034, respectively). Significant correlations between PD-L1+ lymphocytes and tumour-infiltrating CD4+, Foxp3+CD4+, IL-17A+CD4+ T cells and M2 macrophages were found. An analysis of the tumour-immune phenotype revealed a significant association between PD-L1 expression and IL17+CD4+ and Foxp3+CD4+ immune phenotypes. PD-L1+ lymphocytes are associated with the distribution of CD4+, Foxp3+CD4+, IL17A+CD4+ T cells, M1 and M2 macrophages in TME of resected NSCLC.

Prognostic value of systemic inflammation response index in cancer patients treated with PD-1/PD-L1 immune checkpoint inhibitors: a meta-analysis.

The prognostic significance of the systemic inflammatory response index (SIRI) in patients with cancer receiving programmed cell death 1 (PD-1)/PD-1 ligand 1 (PD-L1) immune checkpoint inhibitors (ICIs) has been widely investigated; however, the results have been conflicting. As such, the present meta-analysis aimed to analyze the precise significance of the SIRI in predicting prognosis in patients with cancer undergoing ICI therapy. A comprehensive literature search of the Web of Science, PubMed, Embase, and Cochrane Library databases for relevant studies, published from inception to April 25, 2024, was performed. The SIRI was analyzed for its prognostic utility in patients undergoing ICI therapy by calculating combined hazard ratios (HRs) and corresponding 95% confidence intervals (CIs). Six studies comprising 1133 patients were included in the analysis. Pooled data revealed that a higher SIRI was significantly associated with poor overall survival (OS) (HR 1.96 [95% CI 1.55-2.47]; p < 0.001) and progression-free survival (PFS) (HR 1.41 [95% CI 1.19-1.67]; p < 0.001) for patients who underwent PD-1/PD-L1 ICI treatment. Subgroup analysis revealed that SIRI was markedly associated with dismal OS and PFS, independent of sample size, cut-off value, and survival analysis (p < 0.05). The findings were verified to be robust against publication bias and sensitivity analyses. In summary, an elevated SIRI was significantly associated with OS and PFS in patients with cancer undergoing PD-1/PD-L1 ICI treatment. SIRI may a candidate indicator for predicting the prognosis of patients undergoing ICI therapy.

First-line pembrolizumab with or without chemotherapy for recurrent or metastatic head and neck squamous cell carcinoma: 5-year follow-up of the Japanese population of KEYNOTE‑048.

Previously reported results from phase III KEYNOTE-048 demonstrated similar or improved overall survival (OS) with pembrolizumab or pembrolizumab-chemotherapy versus cetuximab-chemotherapy (EXTREME) in Japanese patients with recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC). We report results in Japanese patients from KEYNOTE-048 after 5years of follow-up. Patients with R/M HNSCC of the oropharynx, oral cavity, hypopharynx, or larynx were randomly assigned 1:1:1 to pembrolizumab, pembrolizumab-chemotherapy, or EXTREME. Primary endpoints were OS and progression-free survival. Efficacy was evaluated in the programmed cell death ligand 1 (PD-L1) combined positive score (CPS) ≥ 20, PD-L1 CPS ≥ 1, and total Japanese populations. In Japan, 67 patients were enrolled (pembrolizumab, n = 23; pembrolizumab-chemotherapy, n = 25; EXTREME, n = 19). Median follow-up was 71.0months (range, 61.2-81.5); data cutoff, February 21, 2022. 5-year OS rates with pembrolizumab versus EXTREME were 35.7% versus 12.5% (hazard ratio [HR] 0.38; 95% CI 0.13-1.05), 23.8% versus 12.5% (HR 0.70; 95% CI 0.34-1.45), and 30.4% versus 10.5% (HR 0.54; 95% CI 0.27-1.07) in the PD-L1 CPS ≥ 20, CPS ≥ 1, and total Japanese populations, respectively. 5-year OS rates with pembrolizumab-chemotherapy versus EXTREME were 20.0% versus 14.3% (HR 0.79; 95% CI 0.27-2.33), 10.5% versus 14.3% (HR 1.18; 95% CI 0.56-2.48), and 8.0% versus 12.5% (HR 1.11; 95% CI 0.57-2.16) in the PD-L1 CPS ≥ 20, CPS ≥ 1, and total Japanese populations, respectively. After 5years of follow-up, pembrolizumab and pembrolizumab-chemotherapy showed long-term clinical benefits; results further support these treatments as first-line options for Japanese patients with R/M HNSCC. NCT02358031.

Prognostic Significance of Programmed Cell Death-Ligand 1 Expression in Tobacco Associated Oral Squamous Cell Carcinoma: An Immunohistochemical Based Cross-Sectional Study.

Advancements in immuno-oncology have dramatically transformed cancer treatment. Immunotherapy, targeting immune check point proteins, notably Programmed cell death ligand 1 (PD-L1) and its receptor Programmed Cell Death-1 (PD-1) which modulate the activity of immune response in Head and Neck squamous cell carcinomas (HNSCC), is an area of much research. The immunohistochemical expression of PD-L1 in cancer cells has been proposed as a predictive biomarker for selecting candidates for immunotherapy. Thus, the present study was undertaken to study the expression of PD-L1 in the primary tumour cells and evaluate its correlation with various clinicopathological parameters and prognosis in tobacco associated oral squamous cell carcinomas (OSCC). Expression of PD-L1 was investigated in 75 surgically resected cases of OSCC by immunohistochemistry and its association with different clinicopathological features and prognosis was analysed. PD-L1 protein was detected in 68% (51 cases) of cases. Tumour stage (p = 0.04), lymph node (LN) metastasis (p < 0.01) and moderate to marked tumour infiltrating lymphocytes (TILs) (p < 0.05), significantly correlated with the PD-L1 expression in the primary tumour. PD-L1 expression did not show a significant association with overall survival (OS) rate, however, patients with positive PD-L1 expression showed a poorer survival rate. Patients exhibiting nodal positivity had the worst prognosis (p < 0.005). These data demonstrated a significant association of ≥ 5% PD-L1 expression in the primary tumour and the presence of LN metastasis, moderate to marked TILs and advancing tumour stage, thus, making it a plausible immunotherapeutic target molecule in OSCC patients.

Investigation of Programmed Death Ligand-1 as a New Prognostic Biomarker in Pancreatic Cancer Patients.

Pancreatic cancer is one of the most lethal and fast-growing cancers with a poor prognosis. Herein, we report the expression of programmed death ligand 1 (PD-L1) as a new prognostic biomarker in pancreatic cancer progression analysis at the clinical level. Immunohistochemistry was performed on 86 clinically proven cases of pancreatic cancer tissue microarrays (TMAs) using anti-PD-L1 antibodies. Histoscore was done, and a variety of cutoffs were identified for analyses of the results. The chi-square test and Kaplan-Meier method were used to find the association between pancreatic cancer and various clinicopathological variables and the overall survival of the patients. PD-L1 expression was associated with histological grade and recurrence of the disease for epithelial and stromal staining at 10 histoscores. In addition, PD-L1 expression was strongly associated with lymph node involvement at the stromal 20 histoscore. The tumor stage of pancreatic cancer had an association with PD-L1 expression with epithelial and stromal 20 histoscores for all comparisons. At a stromal 20 histoscore, overall survival in high-low expression of PD-L1 was 7-19 months, and at a nuclear/cytoplasmic 10 histoscore, it was 9-28 months (p = 0.0001), respectively. Overall, PD-L1 overexpression in subcellular compartments was associated with disease aggression phenotypes and poor patient survival. Overexpression of PD-L1 was directly linked to pancreatic cancer progression and a poor survival rate. Therefore, PD-L1 may be used as a prognostic biomarker in the diagnosis, treatment, and management of pancreatic cancer patients.

Dual PD-L1/SOX10 Immunohistochemistry Combined With Digital Imaging Enhances Stratification Accuracy of Patients With Metastatic Melanoma.

Immune checkpoint inhibitor therapy has demonstrated an overall survival benefit in patients with advanced melanoma. Though the significance of programmed death-ligand 1 (PD-L1) expression on melanoma cells as a predictive biomarker of response remains inconclusive, some reports indicate that a PD-L1 expression of <1% of tumor cells may be associated with better outcomes with dual immunotherapy. Adequate patient selection for combination therapy is critical given the higher frequency of adverse effects compared with monotherapy. Immunohistochemical (IHC) PD-L1 interpretation in tumor cells is challenging when inflammatory cells are present and cutoffs are low. We studied 36 metastatic melanoma biopsies from Immune checkpoint inhibitor-naive patients, previously stained and scored for PD-L1 IHC using the tumor proportion score (TPS). Cases were classified into 3 groups: <1%, 1% to 5%, and >5%. After de-coverslipping, SRY-related HMG-box-10 (SOX10) IHC was performed on PD-L1 IHC slides with a red chromogen, and subsequently scanned and scored by ≥2 dermatopathologists. This assessment determined that 25% of cases (9/36) had a TPS ≥ 1%, in contrast to the single IHC assay (63.8%). The majority of the 1-5% group (11/13, 84.6%) underwent a change of category to <1% TPS. In the >5% group, 60% of cases (6/10) were downgraded to <1% and 1% to 5% (4 and 2 cases, respectively). Our study suggests that PD-L1 IHC evaluation could benefit from dual PD-L1/SOX10 IHC. Dual IHC is expected to decrease the interference caused by PD-L1 expression on inflammatory cells, and digital imaging proves useful for the preservation and analysis of stains. Refining PD-L1 evaluation in metastatic melanoma may improve clinical decisions between single and combination immunotherapy, with potentially profound consequences in response and quality of life.

Dual MAPK Inhibition Triggers Pro-inflammatory Signals and Sensitizes BRAF V600E Glioma to T Cell-Mediated Checkpoint Therapy.

BRAF V600E pediatric low-grade gliomas frequently transform into high-grade gliomas (HGG) and poorly respond to chemotherapy, resulting in high mortality. Although combined BRAF and MEK inhibition (BRAFi+MEKi) outperforms chemotherapy, ∼70% of BRAF V600E HGG patients are therapy resistant and undergo unbridled tumor progression. BRAF V600E glioma have an immune-rich microenvironment suggesting that they could be responsive to immunotherapy but effects of BRAFi+MEKi on anti-tumor immunity are unclear. Using patient tumor tissue before and after BRAFi+MEKi, two novel syngeneic murine models of BRAF V600E HGG, and patient-derived cell lines, we examined the effects of clinically relevant BRAFi+MEKi with dabrafenib and trametinib on tumor growth, cell states, and tumor-infiltrating T cells. We find that BRAFi+MEKi treatment: i) upregulated programmed cell death protein-1 (PD-1) signaling genes and PD-1 ligand (PD-L1) protein expression in murine BRAF V600E HGG by stimulating IFNγ and IL-27, ii) attenuated T cell activity by IL-23, IL-27 and IL-32 production, which can promote the expansion of regulatory T cells, and iii) induced glial differentiation linked to a therapy-resistant PD-L1+ compartment through Galectin-3 secretion by tumor cells. Murine BRAF V600E HGG shrinkage by BRAFi+MEKi is associated with the upregulation of interferon-gamma response genes, MHC class I/II expression, and antigen presentation and processing programs, indicative of increased anti-tumor immunity. Combined BRAFi+MEKi with therapeutic antibodies inhibiting the PD-1 and cytotoxic T-lymphocyte associated protein 4 (CTLA-4) immune checkpoints re-activate T cells and provide a survival benefit over single therapy in a T cell-dependent manner. The quadruple treatment overcame BRAFi+MEKi resistance by invigorating T cell-mediated anti-tumor immunity in murine BRAF V600E HGG. PD-L1 expression was elevated in human BRAF-mutant versus BRAF-wildtype glioblastoma clinical specimen, complementing experimental findings and suggesting translational relevance for patient care.

A Review of Immunotherapy for Head and Neck Cancer

The introduction of immune checkpoint inhibitors (ICIs) to oncological care has transformed the management of various malignancies, including head and neck squamous cell carcinoma (HNSCC), offering improved outcomes. The first-line treatment of recurrent and malignant HNSCC for many years was combined platinum, 5-fluorouracil, and cetuximab. Recently, the ICI pembrolizumab was approved as a first-line treatment, with or without chemotherapy, based on tumor and immune cell percentage of programmed-death ligand 1 (PD-L1). Multiple head and neck (HN) cancer trials have subsequently explored immunotherapies in combination with surgery, chemotherapy, and/or radiation. Immunotherapy regimens may be personalized by tumor biomarker, including PD-L1 content, tumor mutational burden, and microsatellite instability. However, further clinical trials are needed to refine biomarker-driven protocols and standardize pathological methods to guide combined regimen timing, sequencing, and deescalation. Gaps remain for protocols using immunotherapy to reverse oral premalignant lesions, particularly high-risk leukoplakias. A phase II nonrandomized controlled trial, using the ICI nivolumab, showed a 2-y cancer-free survival of 73%, although larger trials are needed. Guidelines are also needed to standardize the role of dental evaluation and care before, during, and after immunotherapy, specifically in regard to oral immune-related adverse events and their impact on cancer recurrence. Standardized diagnostic and oral care coordination strategies to close these gaps are needed to ensure continued success of HN cancer immunotherapy.