Programmed Death-ligand 1 Expression Research Articles

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

In the era of personalized medicine and treatment optimization, use of immune biomarkers holds promise for estimating the prognosis of patients with head and neck squamous cell carcinoma (HNSCC) undergoing definitive treatment. To evaluate the prognostic potential of immune biomarkers, we conducted a prospective monocentric cohort study with loco-regionally advanced HNSCC patients indicated for definitive radiotherapy/radiochemotherapy at the Department of Oncology, Ostrava University Hospital, Czech Republic, between June 2020 and August 2023. We focused on the expression of programmed death ligand 1 (PD-L1) and tumor-infiltrating lymphocytes (TILs) relative to overall survival (OS) and specific survival rates. Associations between biomarkers and survival rates were assessed by crude and adjusted hazard ratios (cHR, aHR, respectively) obtained from Cox proportional hazards regression. Among a total of 55 patients within a median follow-up of 19.7 months, there were 21 (38.2%) all-cause deaths and 15 (27.3%) cancer-related deaths. An overall survival (OS) rate of 61.8% and a disease-specific survival (DSS) rate of 72.7% were recorded. A significant association between survival rates and a ≥10% difference in PD-L1 expression on immune versus tumor cells (high PD-L1IC expression) was documented regardless of the type of analysis (univariate or multivariate). In addition, a stronger association was confirmed for OS and the composite biomarker high PD-L1IC expression along with either median-higher CD8+ TIL count or increased TIL density ≥30%, as indicated by an aHR of 0.08 (95% CI, 0.01 to 0.52) and 0.07 (95% CI, 0.01 to 0.46), respectively. Similar results were demonstrated for other specific survival rates. The early outcomes of the present study suggest the utility of a strong prognostic factor involving a composite biomarker high PD-L1IC expression along with increased TIL density in HNSCC patients undergoing definitive radiotherapy and radiochemotherapy. The study is registered with Clinicaltrials.gov. - NCT05941676.

PD-L1 expression in pancreaticobiliary adenosquamous carcinoma: a single-institution case series.

The programmed cell death protein 1 (PD-1)/programmed cell death ligand 1 (PD-L1) pathway is a potent negative regulator of T-cell-mediated immune response that is upregulated in many neoplasms. Pancreaticobiliary adenosquamous carcinoma (PB-ASC) is an aggressive cancer that carries a poorer prognosis compared with pure pancreaticobiliary adenocarcinoma (PB-AC). To date, there is little published information regarding PD-L1 expression in PB-ASC. The aim of the study was to examine the relationship between PD-L1 expression and tumor-infiltrating lymphocytes in PB-ASC and PB-AC. We evaluated 15 PB-ASCs (10 pancreatic, 5 gallbladder) and 34 control PB-ACs (22 pancreatic ductal, and 12 gallbladder) for tumor expression of PD-L1 using anti-PD-L1 (E1L3N) antibody. All tumors were classified into three immune phenotypes: immune inflamed (II), immune excluded (IE), and immune desert (ID) according to the distribution of tumor-infiltrating lymphocytes in tumor tissues. The frequency of PD-L1 expression was significantly higher in PB-ASC (10/15; 66.7%) than in PB-AC (3/34; 8.8%). In PB-ASC, PD-L1 expression occurred exclusively in the squamous component in six cases, exclusively in the glandular component in one case, and in both the squamous and the glandular components in three cases. PD-L1 expression in PB-ASC was irrespective of the tumor immune status, whereas its expression in PB-AC was observed only in tumors with the II or IE phenotype. The ID phenotype was relatively rare (4/15; 26.7%) in PB-ASC compared with PB-AC (22/34; 65%; P=0.02). PB-ASCs are notably enriched in inflammatory response and showed significantly higher PD-L1 expression than PB-AC (P<0.001), suggesting a potential therapeutic role for immune checkpoint inhibitors in managing patients with PB-ASC.

Comparison of programmed death-ligand 1 expression in adenocarcinoma and squamous cell carcinoma of the cervix in paraffin blocks of patients with cervical cancer.

Cervical cancer (CC) is a common malignancy in women, predominantly caused by human papillomavirus. The most subtypes are adenocarcinomas (AC) and squamous cell carcinomas (SCC), which show various features and treatment responses. Programmed death-ligand 1 (PD-L1) and programmed cell death protein 1 (PD-1) as Immune checkpoint molecules, play a role in immune evasion. We investigated PD-L1 expression in AC and SCC of the cervix and explored its link to clinical characteristics. The present cross-sectional research was done between 2016 and 2022 on samples in Shahid Beheshti University of Medical Sciences-affiliated hospitals in Iran. Histological tissue samples of CCs (16 AC and 48 SCC) were assessed, and clinical information was obtained by reviewing their medical documents. PD-L1 expression was evaluated by immunohistochemistry and we used the combined positive score. SCC cases showed a higher (not significant) PD-L1 expression. The PD-L1 expression and clinical characteristics were not significantly correlated in both subgroups. Although SCC cases exhibited higher PD-L1 expression, this difference was non-significant. More investigations should highlight the role of PD-L1 in CC and the potential benefits of immunotherapy.

PD-L1 Immunohistochemical Expression in Endometrial Carcinoma: Egyptian Cross-Sectional Study.

Endometrial carcinoma (EC) is the most common cancer of the female genital tract. According to the recently evolved strategies of cancer immunotherapy, immune checkpoints inhibitors are one of the most crucial strategies. Programmed Death Ligand 1 (PD-L1) is an important immune checkpoint regulator. PD-L1 antibodies have shown efficacy in clinical trials of some malignancies. Some of these antibodies have been approved for clinical usage by the Food and Drug Administration (FDA). This retrospective study included a total of 100 ECs, collected from archived, formalin-fixed, paraffin-embedded tissue blocks of hysterectomy specimens of Egyptian females. The samples were immunohistochemically analyzed for PD-L1 expression (in both tumor cells; TCs and tumor infiltrating leucocytes; TILs) by a semiquantitative score (0 to 4), with cutoff points of (0: <1% of the cells, 1: 1% to 4%, 2: 5% to 9%, 3: 10% to 49%, and 4: ≥ 50%). Membranous staining only was considered positive. PD-L1 was highly expressed in ECs (67% TCs+ and 61% TILs+), with statistically significant relationships with age, lympho-vascular space invasion (LVSI) and TILs score (P = 0.006, 0.016 and <0.005 respectively). However, no statistically significant relationships were detected between PD-L1 expression and the following parameters: histological type, histological grade, pathological stage (pT) or FIGO stage, myometrial, cervical, adnexal/serosal, parametrial involvements and nodal metastasis, as well as ESMO risk stratification system. Moreover, statistically significant relationships were achieved when correlating TILs score with tumor grade and LVSI (P = 0.034 and 0.012 respectively). Also, comparing endometrial hyperplasia (EH) PD-L1 and TCs PDL1 median scores achieved statistically significant relationship (P = 0.001). Our results concluded that PD-L1 expression was greater in both TCs and TILs in a subgroup of patients that have advanced age, LVSI and are TILs-rich, identifying them as potential candidates for anti-PD-1/PD-L1 immunotherapy.

Efficacy of neoadjuvant chemo-immunotherapy in non-small cell lung cancer: a real-world, multicenter, retrospective study.

Resectable non-small cell lung cancer (NSCLC) patients have a high risk of recurrence. Multiple randomized controlled trials (RCTs) have shown that neoadjuvant chemo-immunotherapy brings new hope for these patients. The study aims to evaluate the safety, surgery-related outcomes and oncological outcomes for neoadjuvant chemo-immunotherapy in real-world setting with a large sample size and long-term follow-up. Patients with clinical stage IB-IIIB NSCLC who received neoadjuvant chemo-immunotherapy at two Chinese institutions were included in this retrospective cohort study. Surgical and oncological outcomes of the enrolled NSCLC patients were collected and analyzed. There were 158 patients identified, of which 124 (78.5%) were at stage IIIA-IIIB and the remaining 34 (21.5%) were at stage IB-IIB. Forty-one patients (25.9%) received two cycles of neoadjuvant treatment, 80 (50.6%) had three cycles, and 37 (23.4%) had four cycles. Twenty-four patients (15.2%) experienced grade 3 or worse immune-related adverse events. The median interval time between the last neoadjuvant therapy and surgery was 37 [interquartile range (IQR), 31-43] days. Fifty-eight out of 96 (60.4%) central NSCLC patients who were expected to undergo complex surgery had the scope or the difficulty of operation reduced. Ninety-five (60.1%) patients achieved major pathologic response (MPR), including 62 (39.2%) patients with pathologic complete response (pCR). Multivariate regression analysis showed that no clinical factor other than programmed death-ligand 1 (PD-L1) expression was predictive of the pathological response. The median follow-up time from diagnosis was 27.1 months. MPR and pCR were significantly associated with improved progression-free survival (PFS) and overall survival (OS). Neither stage nor PD-L1 expression was significantly associated with long-term survival. The neoadjuvant chemo-immunotherapy is a feasible strategy for NSCLC with a favorable rate of pCR/MPR, modified resection and 2-year survival. No clinical factor other than PD-L1 expression was predictive of the pathological response. pCR/MPR may be effective surrogate endpoint for survival in NSCLC patients who received neoadjuvant chemo-immunotherapy.

FOXA1/UBE2T Inhibits CD8+T Cell Activity by Inducing Mediates Glycolysis in Lung Adenocarcinoma.

Immune escape is a key factor influencing survival rate of lung adenocarcinoma (LUAD) patients, but molecular mechanism of ubiquitin binding enzyme E2T (UBE2T) affecting immune escape of LUAD remains unclear. The objective was to probe role of UBE2T in LUAD. Bioinformatics means were adopted for analyzing UBE2T and forkhead box A1 (FOXA1) expression in LUAD tissues, the gene binding sites, the pathway UBE2T regulates, and the correlation between UBE2T and glycolysis genes. Dual luciferase and chromatin immunoprecipitation (ChIP) assays were conducted for validating the binding relationship between the two genes. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot were employed to evaluate UBE2T, FOXA1, and programmed death ligand 1 (PD-L1) levels in cancer cells. MTT assay was conducted for detecting cell viability. Cytotoxicity assay detected CD8+T cell toxicity. Cytokine expression was assayed by enzyme linked immunosorbent assay (ELISA). Extracellular acidification rate (ECAR) and oxygen consumption rate (OCR) were assayed by extracellular flow analyzer. Glycolytic gene expression was analyzed by qRT-PCR, and glycolysis-related indicators were detected by ELISA. Immunohistochemistry (IHC) detected CD8+T cell infiltration in tumor tissues. FOXA1 and UBE2T were up-regulated in LUAD, and a binding site existed between UBE2T and FOXA1. Overexpressing UBE2T could increase PD-L1 expression and inhibit toxicity of CD8+T cells to LUAD cells. Overexpressing UBE2T repressed CD8+T cell activity in LUAD by activating the glycolysis pathway, and the addition of glycolysis inhibitor 2-deoxy-d-glucose (2-DG) reversed the above results. Mechanistically, FOXA1 promoted the immune escape of LUAD by up-regulating UBE2T and thus mediating glycolysis. In vivo experiments revealed that UBE2T knockdown hindered tumor growth, inhibited PD-L1 expression, and facilitated CD8+T cell infiltration. FOXA1 up-regulated the expression of UBE2T, which activated glycolysis, and thus inhibited activity of CD8+T cells, causing immune escape of LUAD.

Hyperoside Inhibits RNF8-mediated Nuclear Translocation of β-catenin to Repress PD-L1 Expression and Prostate Cancer.

Hyperoside is a flavonol glycoside isolated from Hypericum perforatum L. that has inhibitory effects on cancer cells; however, its effects on prostate cancer (PCa) remain unclear. Therefore, we studied the anti-PCa effects of hyperoside and its underlying mechanisms in vitro and in vivo. This study aimed to explore the mechanism of hyperoside in anti-PCa. 3-(4,5-Dimethyl-2-Thiazolyl)-2,5-Diphenyl Tetrazolium Bromide (MTT), transwell, and flow cytometry assays were used to detect PCa cell growth, invasion, and cell apoptosis. Immunoblot analysis, immunofluorescence, immunoprecipitation, and quantitative real-time PCR (qRT-PCR) were used to analyze the antitumor mechanism of hyperoside. Hyperoside inhibited PCa cell growth, invasion, and cell cycle and induced cell apoptosis. Furthermore, RING finger protein 8 (RNF8), an E3 ligase that assembles K63 polyubiquitination chains, was predicted to be a direct target of hyperoside and was downregulated by hyperoside. Downregulation of RNF8 by hyperoside impeded the nuclear translocation of β-catenin and disrupted the Wnt/β-catenin pathway, which reduced the expression of the target genes c-myc, cyclin D1, and programmed death ligand 1 (PD-L1). Decreased PD-L1 levels contributed to induced immunity in Jurkat cells in vitro. Finally, in vivo studies demonstrated that hyperoside significantly reduced tumor size, inhibited PD-L1 and RNF8 expression, and induced apoptosis in tumor tissues of a subcutaneous mouse model. Hyperoside exerts its anti-PCa effect by reducing RNF8 protein, inhibiting nuclear translocation of β-catenin, and disrupting the Wnt/β-catenin pathway, in turn reducing the expression of PD-L1 and improving Jurkat cell immunity.

Three-Year Overall Survival Outcomes and Correlative Analyses in Patients With NSCLC and High (50%–89%) Versus Very High (≥90%) Programmed Death-Ligand 1 Expression Treated With First-Line Pembrolizumab or Cemiplimab

IntroductionResponses to first-line programmed cell death protein 1 inhibition vary among patients with metastatic NSCLC and a programmed death-ligand 1 (PD-L1) tumor proportion score (TPS) greater than or equal to 50%. We previously reported improved clinical outcomes to first-line programmed cell death protein 1 inhibition in patients with metastatic NSCLC with a PD-L1 TPS of greater than or equal to 90% versus 50% to 89% in a pilot study. Here, we report the three-year survival with first-line pembrolizumab and cemiplimab in two large independent cohorts of patients with PD-L1 TPS greater than or equal to 90% versus 50% to 89% and characterize genomic and immunophenotypic differences between these PD-L1 expression groups, which were largely unknown. MethodsWe analyzed three-year outcomes of the following two independent cohorts: (1) a multicenter cohort of patients from four academic centers in the United States treated with pembrolizumab and (2) EMPOWER-Lung 1, randomized, phase III trial comparing first-line cemiplimab with chemotherapy. Tumor genomic profiling and multiplexed immunofluorescence were performed to evaluate genomic and immunophenotypic correlates of very high PD-L1 expression. ResultsAt three years of follow-up, progression-free survival (hazard ratio [HR], 0.69; p < 0.001) and overall survival (HR, 0.70; p < 0.01) to first-line commercial pembrolizumab were significantly improved in patients with a PD-L1 TPS greater than or equal to 90% versus 50% to 89%. In the EMPOWER-Lung 1, patients assigned to the cemiplimab arm with a PD-L1 TPS greater than or equal to 90% also had significant improvements in progression-free survival (HR, 0.53; p < 0.0001) and overall survival (HR, 0.63; p = 0.007) compared with those with a PD-L1 of 50% to 89%. Tumor genomic profiling of 553 NSCLC samples revealed that mutations in STK11 and SMARCA4 were significantly more frequent in tumors with a PD-L1 TPS of 50% to 89% compared with those with a PD-L1 TPS greater than or equal to 90% (Q < 0.15), whereas BRCA2 was enriched in NSCLC samples with a PD-L1 TPS greater than or equal to 90% (Q < 0.15). Multiplexed immunofluorescence on 93 NSCLC samples identified higher intratumoral CD8+PD1+ T cells (p = 0.02) in tumors with PD-L1 TPS greater than or equal to 90% versus 50% to 89%. ConclusionPembrolizumab and cemiplimab were found to have long-term survival benefit and favorable genomic and immunophenotypic profile in patients with advanced NSCLC with PD-L1 TPS greater than or equal to 90% compared with TPS 50% to 89%.

Detection and Significance of Molecular Markers in Immunotherapy and Targeted Therapy of Colorectal Cancer in Tibet

Objective To study the expression of SWI/SNF-related,matrix-associated,actin-dependent regulator of chromatin,subfamily A,member 4(SMARCA4)/Brahma-related gene 1,V-raf murine sarcoma viral oncogene homolog B(BRAF),P53,programmed cell death protein-1(PD-1),and programmed death-ligand 1(PD-L1),and changes in the expression of BRAF and neurotrophic tyrosine receptor kinase(NTRK) in the patients with colorectal cancer in Tibet,thereby providing a basis for targeted therapy and immunotherapy for this disease in Tibet. Methods A total of 64 patients with colorectal cancer resected in the Tibet Autonomous Region People's Hospital from January 2015 to July 2021 were enrolled in this study.The expression of SMARCA4,BRAF,P53,PD-1,and PD-L1 was detected by immunohistochemical staining.The gene fusion involving NTRK1,NTRK2,and NTRK3 was detected by fluorescence in situ hybridization,and the BRAF V600E gene mutation by polymerase chain reaction. Results The 64 patients with colorectal cancer were at a male-to-female ratio of 1.21∶1,with the mean age of (56.59±13.27) years.The tumors were located in the colon in 46(71.88%) patients and in the rectum in 18(28.12%) patients.Sixty(93.75%) patients presented adenocarcinoma,and 4(6.25%) patients presented other types of tumors.The patients in T1/T2 and T3/T4 phases accounted for 17.19%(n=11) and 82.81%(n=53),respectively.Lymph node metastasis occurred in 24(37.50%) patients.The immunohistochemical staining results showed partially down-regulated or absent expression of SMARCA4 in 1(1.56%) patient,positive BRAF expression in 4(6.25%) patients,and mutant expression of P53 in 35(54.69%) patients.The PD-1-expressing tumor associated immune cell was proportion score<10% in 45(70.31%) patients and≥10% in 19(29.69%) patients.The PD-L1 combined positive score was<10 in 52(81.25%) patients and≥10 in 12(18.75%) patients.The gene fusion of NTRK1,NTRK2,and NTRK3 was negative in all the patients,and BRAF V600E gene mutation was positive in 4(6.25%) patients.The SMARCA4 gene alteration was not detected in the patient with partial expression missing of SMARCA4.The PD-L1 combine positive score was correlated with the deficient mismatch repair(dMMR)/microsatellite instability-high (MSI-H) and the PD-1 expression (χ2=10.223,P=0.001;χ2=11.979,P=0.001). Conclusions The down-regulated or absent SMARCA4 expression and NTRK gene fusion are rare in the patients with colorectal cancer in Tibet.A few patients present BRAF V600E gene mutations,and Pan-TRK and BRAF expression can be used for the primary screening of NTRK gene fusion and BRAF gene mutation.The patients with dMMR/MSI-H are prone to high expression of PD-L1 and expected to benefit from immunotherapy.No significant correlation exists between P53 mutation and PD-L1 expression.The high expression of PD-1 is positively correlated with the high expression of PD-L1.

Adenosine increases PD-L1 expression in mesenchymal stromal cells derived from cervical cancer through its interaction with A2AR/A2BR and the production of TGF-β1.

Mesenchymal stromal cells (MSCs) together with malignant cells present in the tumor microenvironment (TME), participate in the suppression of the antitumor immune response through the production of immunosuppressive factors, such as transforming growth factor beta 1 (TGF-β1). In previous studies, we reported that adenosine (Ado), generated by the adenosinergic activity of cervical cancer (CeCa) cells, induces the production of TGF-β1 by interacting with A2AR/A2BR. In the present study, we provide evidence that Ado induces the production of TGF-β1 in MSCs derived from CeCa tumors (CeCa-MSCs) by interacting with both receptors and that TGF-β1 acts in an autocrine manner to induce the expression of programmed death ligand 1 (PD-L1) in CeCa-MSCs, resulting in an increase in their immunosuppressive capacity on activated CD8+ T lymphocytes. The addition of the antagonists ZM241385 and MRS1754, specific for A2AR and A2BR, respectively, or SB-505124, a selective TGF-β1 receptor inhibitor, in CeCa-MSC cultures significantly inhibited the expression of PD-L1. Compared with CeCa-MSCs, MSCs derived from normal cervical tissue (NCx-MSCs), used as a control and induced with Ado to express PD-L1, showed a lower response to TGF-β1 to increase PD-L1 expression. Those results strongly suggest the presence of a feedback mechanism among the adenosinergic pathway, the production of TGF-β1, and the induction of PD-L1 in CeCa-MSCs to suppress the antitumor response of CD8+ T lymphocytes. The findings of this study suggest that this pathway may have clinical importance as a therapeutic target.

Clinical status and perspective on the application of immunotherapy combined with chemotherapy in advanced non-small cell lung cancer: a review.

The therapeutic landscape of advanced non-small cell lung cancer (NSCLC) has been significantly improved by developing immunotherapy represented by programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1) immune checkpoint inhibitors (ICI). Furthermore, immunotherapy combined with chemotherapy is an essential treatment strategy for driver-negative advanced NSCLC, especially in a population with PD-L1 <50%, and leads to long-term survival in the entire population regardless of the PD-L1 expression status. However, specific challenges must be overcome, including how to use immunotherapy with chemotherapy in clinics. Furthermore, the application of immunotherapy with chemotherapy in populations such as elderly patients and patients with brain metastases, oligometastases, epidermal growth factor receptor (EGFR) gene mutation, anaplastic lymphoma kinase (ALK) gene rearrangements, and other driver gene-positive populations must be further explored. The biomarkers associated with immunotherapy and chemotherapy are still unclear, and the search for predictive biomarkers can contribute toward more precise and personalized immunotherapy. Furthermore, treatment strategies after immunotherapy and chemotherapy resistance are of significant focus clinically, and clinical studies with multiple combination therapy strategies are ongoing. Therefore, based on the reported status of immunotherapy combined with chemotherapy for advanced NSCLC, this study conducted a comprehensive literature review by searching keywords "PD-1 and PD-L1, immune checkpoint inhibitor (ICI), and NSCLC" in MEDLINE, major conferences, and major clinical research projects to elucidate the therapeutic efficacy of immunotherapy combined with chemotherapy as the current first-line treatment approach for various types of NSCLC patients. Additionally, it addresses several pressing challenges associated with immunotherapy combined with chemotherapy, including enhancing treatment response and survival rate in specific patient populations and identifying potential biomarkers.

PD-L1 Expression in Neoplastic and Immune Cells of Thymic Epithelial Tumors: Correlations with Disease Characteristics and HDAC Expression.

Programmed death-ligand 1 (PD-L1) expression in neoplastic and immune cells of the tumor microenvironment determines the efficacy of antitumor immunity, while it can be regulated at the epigenetic level by various factors, including HDACs. In this study, we aim to evaluate the expression patterns of PD-L1 in thymic epithelial tumors (TETs), while we attempt the first correlation analysis between PD-L1 and histone deacetylases (HDACs) expression. Immunohistochemistry was used to evaluate the expression of PD-L1 in tumor and immune cells of 91 TETs with SP263 and SP142 antibody clones, as well as the expressions of HDCA1, -2, -3, -4, -5, and -6. The PD-L1 tumor proportion score (TPS) was higher, while the immune cell score (IC-score) was lower in the more aggressive TET subtypes and in more advanced Masaoka-Koga stages. A positive correlation between PD-L1 and HDAC-3, -4, and -5 cytoplasmic expression was identified. Higher PD-L1 expression in neoplastic cells and lower PD-L1 expression in immune cells of TETs characterizes more aggressive and advanced neoplasms. Correlations between PD-L1 and HDAC expression unravel the impact of epigenetic regulation on the expression of immune checkpoint molecules in TETs, with possible future applications in combined therapeutic targeting.

PD-L1 Expression in High-Risk Non-Muscle-Invasive Bladder Cancer Is Influenced by Intravesical Bacillus Calmette-Guérin (BCG) Therapy.

In the expanding landscape of immune checkpoint inhibitors (CPI) in high-risk (HR) non-muscle-invasive bladder cancer (NMIBC), the role of programmed death ligand 1 (PD-L1) as prognostic and predictive is increasingly significant. However, data evaluating its variability and susceptibility to Bacillus Calmette-Guérin (BCG) therapy in HR NMIBC patients is scarce. This retrospective study analyzed 126 HR NMIBC tissue samples from 63 patients (38× BCG-treated, 25× BCG-naïve) at two time points to assess PD-L1 expression using the 'combined positivity score' (CPS) with the 22C3 DAKO antibody method and correlated it with clinicopathological parameters. A CPS > 10 defined PD-L1 positivity. The impact of initial PD-L1 status and its change over time on time-to-recurrence, progression-free survival, and overall survival (TTR, PFS, OS) was analyzed using Kaplan-Meier and Cox proportional hazard models. BCG treatment significantly increased PD-L1 expression (5.31 vs. 0.22, p = 0.0423), with PD-L1 positive cases rising post-treatment in the BCG group and remaining unchanged in BCG-naïve patients. Multivariate analysis including T-stage, CIS, grading, tumor size, multifocality, age, and sex revealed a significant correlation between PD-L1 status change to positivity and improved TTR (p = 0.03). Our findings demonstrate a potential modulation of the PD-L1 status by an intravesical BCG therapy. However, its prognostic value appears limited.

The predictive value of PD-L1 expression in response to anti-PD-1/PD-L1 therapy for biliary tract cancer: a systematic review and meta-analysis.

Recently, anti-programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) immunotherapy offers promising results for advanced biliary tract cancer (BTC). However, patients show highly heterogeneous responses to treatment, and predictive biomarkers are lacking. We performed a systematic review and meta-analysis to assess the potential of PD-L1 expression as a biomarker for treatment response and survival in patients with BTC undergoing anti-PD-1/PD-L1 therapy. We conducted a comprehensive systematic literature search through June 2023, utilizing the PubMed, EMBASE, and Cochrane Library databases. The outcomes of interest included objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and overall survival (OS) according to PD-L1 expression. Subgroup analyses and meta-regression were performed to identify possible sources of heterogeneity. A total of 30 studies was included in the final analysis. Pooled analysis showed no significant differences in ORR (odds ratio [OR], 1.56; 95% confidence intervals [CIs], 0.94-2.56) and DCR (OR, 1.84; 95% CIs, 0.88-3.82) between PD-L1 (+) and PD-L1 (-) patients. In contrast, survival analysis showed improved PFS (hazard ratio [HR], 0.54, 95% CIs, 0.41-0.71) and OS (HR, 0.58; 95% CI, 0.47-0.72) among PD-L1 (+) patients compared to PD-L1 (-) patients. Sensitivity analysis excluding retrospective studies showed no significant differences with the primary results. Furthermore, meta-regression demonstrated that drug target (PD-1 vs. PD-L1), presence of additional intervention (monotherapy vs. combination therapy), and PD-L1 cut-off level (1% vs. ≥5%) significantly affected the predictive value of PD-L1 expression. PD-L1 expression might be a helpful biomarker for predicting PFS and OS in patients with BTC undergoing anti-PD-1/PD-L1 therapy. The predictive value of PD-L1 expression can be significantly influenced by diagnostic or treatment variables. https://www.crd.york.ac.uk/PROSPERO, identifier CRD42023434114.

Circ_0027791 contributes to the growth and immune evasion of hepatocellular carcinoma via the miR-496/programmed cell death ligand 1 axis in an m6A-dependent manner.

Emerging evidence indicates the critical roles of circular RNAs in the development of multiple cancers, containing hepatocellular carcinoma (HCC). Herein, our present research reported the biological function and mechanism of circ_0027791 in HCC progression. Circ_0027791, microRNA-496 (miR-496), programmed cell death ligand 1 (PDL1), and methyltransferase-like 3 (METTL3) levels were detected by real-time quantitative polymerase chain reaction (RT-qPCR). Cell viability, proliferation, invasion, and sphere formation ability were detected using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide, 5-ethynyl-2'-deoxyuridine, transwell, and sphere formation assays. Macrophage polarization was detected using flow cytometry assay. To understand the role of circ_0027791 during the immune escape, HCC cells were cocultured with peripheral blood mononuclear cells or cytokine-induced killer (CIK) cells in vitro. A xenograft mouse model was applied to assess the function of circ_0027791 in vivo. After prediction using circinteractome and miRDB, the binding between miR-496 and circ_0027791 or PDL1 was validated based on a dual-luciferase reporter assay. Interaction between METTL3 and circ_0027791 was determined using methylated RNA immunoprecipitation (MeRIP)-qPCR, RIP-qPCR, and RNA pull-down assays. Circ_0027791, PDL1, and METTL3 expression were upregulated, and miR-496 was decreased in HCC patients and cells. Moreover, circ_0027791 knockdown might repress proliferation, invasion, sphere formation, M2 macrophage polarization, and antitumor immune response. Circ_0027791 knockdown repressed HCC tumor growth in vivo. In mechanism, circ_0027791 functioned as a sponge for miR-496 to increase PDL1 expression. In addition, METTL3 mediated the m6A methylation of circ_0027791 and stabilized its expression. METTL3-induced circ_0027791 facilitated HCC cell progression partly regulating the miR-496/PDL1 axis, which provided a new prognostic and therapeutic marker for HCC.

A real-world retrospective, observational study of first-line pembrolizumab plus chemotherapy for metastatic non-squamous non-small cell lung cancer with PD-L1 tumor proportion score < 50% (PEMBROREAL).

The phase III Keynote-189 trial established a first-line treatment combining pembrolizumab with pemetrexed and platinum as a standard treatment for patients with stage IV non-small cell lung cancer (NSCLC) without known EGFR and ALK driver mutations and independent of programmed cell death ligand 1 (PD-L1) expression. However, in Italy, eligibility for the National Health Service payment program is limited to patients with PD-L1 <50%. The PEMBROREAL study assesses the real-world effectiveness and safety of pembrolizumab in patients eligible for the National Health Service payment program. PEMBROREAL is a retrospective, observational study on patients with NSCLC who started pembrolizumab combined with pemetrexed and platinum within the reimbursability time window, considered as December 2019 to December 2020. The primary endpoints were to assess progression-free survival (PFS) and overall survival (OS; using the Kaplan-Meier method), response to therapy, and tolerability. Until February 2022, 279 patients (median follow-up: 19.7 months) have been observed. The median PFS was 8.0 months (95% confidence interval: 6.5-9.2). OS was not reached, but we can estimate a 12- to 24-month survival rate for the combined treatment: 66.1% and 52.5%, respectively. PD-L1 expression and Eastern Cooperative Group (ECOG) Performance Status were both associated with PFS and OS. Overall, only 44.4% of patients reported an adverse event, whereas toxicity led to a 5.4% discontinuation rate. The results of the PEMBROREAL study have shown that the combined treatment of pembrolizumab with pemetrexed and platinum is effective for metastatic non-squamous NSCLC, even for patients with PD-L1 levels below 50%, despite the differences in patient demographics and pathological features compared to the Keynote-189 study. The adverse events reported during the study were more typical of chemotherapy treatment rather than immunotherapy, and physicians were able to manage them easily.

Metabolic Tumor Volume as Significant Predictor for Chemotherapy Containing PD-L1 Blocker in Extensive Stage Small Cell Lung Cancer.

Chemo-immunotherapy, including the programmed death ligand 1 (PD-L1) antibody, is an effective treatment for patients with extensive-stage small-cell lung cancer (ES-SCLC). However, no biomarker has been established for the prediction of chemo-immunotherapy. Therefore, we investigated the potential of 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) as a predictive marker. Forty-six patients with ES-SCLC who received 18F-FDG-PET immediately before combined platinum-based chemotherapy with PD-L1 blockade as a first-line treatment were eligible, and the maximum standard uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) on 18F-FDG uptake were evaluated. PD-L1 and tumor infiltrative lymphocytes (TILs) were immunohistochemically analyzed in 36 of the 46 patients. A high MTV was significantly associated with poor performance status and low albumin levels, and there was a significant association between low albumin and high TLG. Univariate analysis identified sex, Brinkman index, and MTV as significant predictors of progression-free survival (PFS), and sex, SUVmax, MTV, and TLG as significant factors of overall survival (OS). Multivariate analysis revealed that sex, Brinkman index, and MTV were independent prognostic factors for PFS, and sex, SUVmax, MTV, and TLG were significant predictors of OS. SUVmax was significantly higher in patients with positive PD-L1 expression than in those with negative expression but was not significantly different between positive and negative TILs. Moreover, the levels of MTV and TLG were not closely associated with the levels of PD-L1 and TILs. MTV or TLG metabolic tumor activity is suitable for the prediction of chemo-immunotherapy outcomes in patients with ES-SCLC.

Metformin Suppresses Both PD-L1 Expression in Cancer Cells and Cancer-Induced PD-1 Expression in Immune Cells to Promote Antitumor Immunity.

Metformin, a drug prescribed for patients with type 2 diabetes, has potential efficacy in enhancing antitumor immunity; however, the detailed underlying mechanisms remain to be elucidated. Therefore, we aimed to identify the inhibitory molecular mechanisms of metformin on programmed death ligand 1 (PD-L1) expression in cancer cells and programmed death 1 (PD-1) expression in immune cells. We employed a luciferase reporter assay, quantitative real-time PCR, immunoblotting analysis, immunoprecipitation and ubiquitylation assays, and a natural killer (NK) cell-mediated tumor cell cytotoxicity assay. A mouse xenograft tumor model was used to evaluate the effect of metformin on tumor growth, followed by flow-cytometric analysis using tumor-derived single-cell suspensions. Metformin decreased AKT-mediated β-catenin S552 phosphorylation and subsequent β-catenin transactivation in an adenosine monophosphate-activated protein kinase (AMPK) activation-dependent manner, resulting in reduced CD274 (encoding PD-L1) transcription in cancer cells. Tumor-derived soluble factors enhanced PD-1 protein stability in NK and T cells via dissociation of PD-1 from ubiquitin E3 ligases and reducing PD-1 polyubiquitylation. Metformin inhibited the tumor-derived soluble factor-reduced binding of PD-1 to E3 ligases and PD-1 polyubiquitylation, resulting in PD-1 protein downregulation in an AMPK activation-dependent manner. These inhibitory effects of metformin on both PD-L1 and PD-1 expression ameliorated cancer-reduced cytotoxic activity of immune cells in vitro and decreased tumor immune evasion and growth in vivo. Metformin blocks both PD-L1 and PD-1 within the tumor microenvironment. This study provided a mechanistic insight into the efficacy of metformin in improving immunotherapy in human cancer.

PD-L1 Expression in Colorectal Carcinoma Correlates with the Immune Microenvironment.

Colorectal carcinoma (CRC) is a common malignancy, with its diverse clinical, pathological, and molecular features. The immune microenvironment of a tumor comprises of interplay between various cells and molecules, and has a significant role in deciding the tumor behavior and overall prognosis. PD-L1 (programmed cell death ligand-1) has been implicated in the regulation of the tumor immune microenvironment (TIME). There is limited data regarding the correlation of PD-L1 expression with immune cell profile in CRCs, especially in the Indian setting. The study aimed to assess the PD-L1 expression in CRC tumor cells and its association with TIME, mismatch repair (MMR), and various other clinicopathological parameters. This is a hospital-based, cross-sectional observational study. PD-L1 expression was assessed at the protein level by immunohistochemistry and mRNA level by qRT-PCR. Immune cell markers (CD4, CD8, CD20, FOXP3, and CD163) were interpreted using the ImageJ Fiji platform. Of the 104 cases, 21% were PD-L1 positive and were more common in right-sided CRCs. PD-L1 positive cases showed significantly higher concentrations of all T-cell subsets (CD4+ , CD8+ , and FOXP3+), CD20+ B-cells, and CD163+ macrophages were noted. No statistical significance was seen between PD-L1 expression with clinical profile, pathological subtype, grade or stage, mismatch repair status (proficient vs deficient), and survival. The present study showed a relatively lower frequency of PD-L1 in CRC from the Eastern Indian cohort. The immune cell concentration in the present study was calculated using image analysis-based objectivised methods. Significant correlation of PD-L1 expression in tumor cells with the tumor-infiltrating immune cells indicated its crucial role in the pathobiology of CRC especially by regulating the TIME. Considering the therapeutic implication of PD-L1 in various malignancies, it may be one of the crucial therapeutic targets in a proportion of cases.

Comparing deep learning and pathologist quantification of cell-level PD-L1 expression in non-small cell lung cancer whole-slide images

Programmed death-ligand 1 (PD-L1) expression is currently used in the clinic to assess eligibility for immune-checkpoint inhibitors via the tumor proportion score (TPS), but its efficacy is limited by high interobserver variability. Multiple papers have presented systems for the automatic quantification of TPS, but none report on the task of determining cell-level PD-L1 expression and often reserve their evaluation to a single PD-L1 monoclonal antibody or clinical center. In this paper, we report on a deep learning algorithm for detecting PD-L1 negative and positive tumor cells at a cellular level and evaluate it on a cell-level reference standard established by six readers on a multi-centric, multi PD-L1 assay dataset. This reference standard also provides for the first time a benchmark for computer vision algorithms. In addition, in line with other papers, we also evaluate our algorithm at slide-level by measuring the agreement between the algorithm and six pathologists on TPS quantification. We find a moderately low interobserver agreement at cell-level level (mean reader-reader F1 score = 0.68) which our algorithm sits slightly under (mean reader-AI F1 score = 0.55), especially for cases from the clinical center not included in the training set. Despite this, we find good AI-pathologist agreement on quantifying TPS compared to the interobserver agreement (mean reader-reader Cohen’s kappa = 0.54, 95% CI 0.26–0.81, mean reader-AI kappa = 0.49, 95% CI 0.27—0.72). In conclusion, our deep learning algorithm demonstrates promise in detecting PD-L1 expression at a cellular level and exhibits favorable agreement with pathologists in quantifying the tumor proportion score (TPS). We publicly release our models for use via the Grand-Challenge platform.