Programmed Death-ligand 1 Expression Research Articles

Impact of the tumor proportion score (TPS) and the combined positive score (CPS) on the use of immunotherapy in patients with metastatic non-small cell lung cancer.

e14611 Background: Expression of programmed cell death ligand 1 (PD-L1) in non-small cell lung cancer (NSCLC) has often been measured by the Tumor Proportion Score (TPS) (1). Recently, the Combined Positive Score (CPS), which evaluates PD-L1 expression in tumor and inflammatory cells and applies to other types of cancer including gastric and head and neck cancers, was found to be equally predictive of the response to immunotherapy in NSCLC (1). In this study, we aimed to conduct a single center retrospective analysis to evaluate the clinical use and impact of using TPS and CPS data in patients with metastatic NSCLC. Methods: Patients with NSCLC who had TPS and CPS scores and received PD-1/PD-L1 inhibitors between 2021-2022 as a monotherapy or in combination with chemotherapy were included. Patients’ data was retrieved from the electronic medical record data and analysis included histopathological data, lung cancer surgical history, presence of EGFR mutation, ALK mutation, Ki67, use of adjuvant chemotherapy, type of immunotherapy used, and development of immune checkpoint inhibitor- related toxicity and treatment as applicable. TPS and CPS positivity was defined as >1 % and >1 respectively. Statistical methods employed included descriptive approaches such as calculated means as well as the Kaplan-Meier estimate. Results: 40 patients with NSCLC were included. Patients’ age ranged from 19 to 82 years old with an average age of 64.3 years old. Most patients had adenocarcinoma (65 %) and were at stage IV (72.5 %). TPS positivity was identified in 29 patients (72.5 %) and CPS positivity was identified in 35 patients (87.5 %). Patients received immunotherapy mostly as first or second line of treatment (90 %). Immune checkpoint inhibitors received by patients were pembrolizumab (50 %), nivolumab (35 %), atezolizumab (12.5 %), and durvalumab (2.5 %). The median overall survival was 16, 12, and 17 months in the <1 %, 1-49 % and > 49 % TPS groups respectively (p= 0.354); while the median overall survival was 11, 16 and 17 months in the <1, 1-49, and > 49 CPS groups respectively (p= 0.417). It is critical to highlight that there were 7 patients (17.5 %) with TPS of zero who had CPS positivity (score range: 1-10). Most of these patients had adenocarcinoma (71.4 %), received pembrolizumab or atezolizumab (85.7 %) and had a median survival of 16 months. Conclusions: The Combined Positive Score (CPS) has proven to be an effective method in evaluating the level of expression of PD-L1 in NSCLC (1,2). Similar to TPS, CPS provides critical information that can be applied to guide the use of immunotherapy, and which can greatly impact patients with NSCLC. 1. De Marchi et al., 2021. 2. Ulas et al., 2023.

Relationship between immune-inflammatory markers and clinical features and deepness of tumor response and prognosis of patients with PD-L1 ≥50% metastatic NSCLC receiving first-line immunotherapy.

e14547 Background: Patients with programmed cell death-ligand 1 (PD-L1) ≥50% metastatic non-small cell lung cancer (NSCLC) treated with first-line immunotherapy have heterogeneous clinical assessment and outcomes. In this study, we sought to identify features of patients with metastatic NSCLC who achieved high deepness of response (HDPR) to first-line immunotherapy, and how these might differ from features predictive of non-high deepness of response (NHDPR). The influence of clinical features on prognosis of patients with PD-L1 ≥50% were further clarified. Methods: This retrospective study analyzed patients with PD-L1≥50% metastatic NSCLC treated with first-line immunotherapy at Beijing Tiantan Hospital between July 2020 and December 2023. All the patients had at least one measurable lesion in lung according to the Response Evaluation Criteria in Solid Tumors (RECIST) v1.1. HDPR was defined as deepness of lung tumor response ≥50%, while NHDPR was defined as deepness of lung tumor response <50% or tumor enlargement. Tumor PD-L1 expression, target mutation, neutrophil-to-lymphocyte ratio (NLR), lactic dehydrogenase (LDH) level, and other prognostic variables were analyzed to identify characteristics enriched in patients achieving HDPR compared to NHDPR. We also investigated the effects of these variables on first-line progression-free survival (PFS) and overall survival (OS) of the patients. Results: A total of 17 patients were included in our retrospective analysis. Seven (41.2%) patients achieved HDPR (range: -50%, -72%) and ten (58.8%) patients achieved NHDPR (range: -13%, -45%). Seven (41.2%) patients had central nervous system (CNS) metastases at the first diagnosis of lung malignancy, and their CNS target lesions shrinkages were observed after therapy (range: -32%, -100%). Lower Th/Ts ratio ( P=0.01) and drug resistance mutations (TP53/KRAS/EGFR) ( P=0.001) were found enriched for NHDPR compared to HDPR. However, no differences were found in tumor PD-L1 expression, NLR, LDH, B lymphocyte subset, NK cell subset, pathological type, T-stage, smoking index, ECOG score, immunotherapeutic schemes, or CNS metastases between the two groups ( P>0.05). With a median follow-up of 26.0 months (range: 17.2-34.8 months), the median first-line PFS and OS were 9.0 months (95% CI: 5.0-13.0) and not reached (NR), respectively. The NLR was identified as an independent prognostic factor on first-line PFS. Patients with an NLR≥4 exhibited a worse median PFS (7.0 months vs. NR; P=0.033; 95%CI: 1.2-80.2) than those with an NLR<4 following first-line immunotherapy. Conclusions: Among patients with PD-L1≥50% metastatic NSCLC who received first-line immunotherapy, lower Th/Ts ratio and drug resistance mutations showed a diminished tumor response and higher NLR ratio exhibited a worse median PFS.

Tislelizumab combined with chemotherapy in advanced thymic tumors.

e20139 Background: Thymic tumors refer to tumors derived from thymic epithelial cells, including thymoma and thymic carcinoma. Most cases in advanced stages when detected, and treatment is still controversial. Since 2018, immunotherapy has gradually been used for a variety of solid tumors and the curative efficacy has been notable. The efficacy of immunotherapy is increasingly improved with the increased expression of programmed death-ligand 1 (PD-L1) by tumor cells. The thymus is an immune-rich organ. PD-L1 expression ranges from 23% to 92% in thymoma, and from 36% to 100% in thymic carcinoma. Thus, immunotherapy has been implicated as having broad prospects in the treatment of thymic tumors. Tislelizumab is an inhibitor of PD-1, which has shown preliminary anti-tumor effects in various solid tumors. The combination of immunotherapy and chemotherapy has produced excellent anti-tumor activity for various types of tumors. However, there is a lack of clinical trial data to support the application of tislelizumab for the treatment of advanced thymic tumors. In this article, the efficacy and safety of tislelizumab combined with chemotherapy were analyzed in eight patients with advanced thymic tumors to provide data for the use of this monoclonal antibody as first-line treatment of advanced thymic tumors. Methods: Here, after obtaining fully informed consent, we report cases involving eight patients with advanced thymic tumors treated with tislelizumab combined with chemotherapy. The clinical characteristics, lesion changes, treatment process, drugs used, drug efficacy, complications or adverse reactions were recorded and followed up to evaluate the efficacy and safety of tislelizumab combined with chemotherapy in the treatment of advanced thymic tumors. Results: This article reports eight cases of advanced thymic tumor treated with tislelizumab combined with chemotherapy. Two patients received tislelizumab combined with chemotherapy as first-line treatment, and the remaining six patients were treated with tislelizumab after poor response to chemotherapy. Five patients achieved a partial response to the combined treatment. Of these, the partial response was retained in three patients after switching to tislelizumab monotherapy. The remaining three patients displayed stable disease after the combined treatment. There were no serious immune-related adverse events during treatment. The side effects of tislelizumab combined with chemotherapy were well tolerated. Conclusions: No clinical study of immunotherapy combined with standard chemotherapy as first-line treatment for advanced unresectable or metastatic thymic epithelial tumors has been described. This article provides strong evidence for the early application or even first-line use of tislelizumab combined with chemotherapy for advanced thymic epithelial tumors. More clinical studies are needed to evaluate the efficacy and safety of tislelizumab in thymic tumors.

PD-L1 immunohistochemistry in gastric cancer: Comparison of combined positive score and tumor area positivity across 28-8, 22C3, and SP263 assays.

2625 Background: The clinical application of programmed death-ligand 1 (PD-L1) immunohistochemistry is complicated by multiple available assays and different testing platforms, scoring algorithms, and cut-offs applied. This study assessed the analytical comparability of three commercially available PD-L1 assays (28-8, 22C3, and SP263) and two scoring algorithms used in gastric cancer (GC). Methods: Serial sections of 100 commercially procured GC samples, selected by the 28-8 assay to represent the dynamic range of PD-L1 expression, were stained with the three in vitrodiagnostic (IVD)-grade PD-L1 assays. Stained slides were blindly and independently evaluated by three trained pathologists for intra- and inter-reader assessment. Scoring was performed using the combined positive score (CPS) and tumor area positivity (TAP) methods, followed by statistical analysis. Digital image analysis (DIA) was used to objectively assess the technical performance of each assay by simulating CPS and TAP scoring methods using the HALO platform. Results: Comparable, specific, staining patterns were observed with the three PD-L1 assays. Pathologist assessment of PD-L1 positivity was reproducible in GC sample cohorts despite discernible variability in the observed staining intensity. When the same PD-L1 cut-offs were applied, inter- and intra-assay assessments of all three assays, using either CPS or TAP scoring methods, demonstrated moderate to almost-perfect (inter-assay Cohen’s kappa [κ] ranged from 0.47 to 0.83) and substantial to almost-perfect (intra-assay κ ranged from 0.77 to 1.00) agreement, respectively. Moreover, inter-pathologist evaluation showed a significant level of reproducibility (intraclass correlation coefficient (ICC) ≥0.92). DIA confirmed no difference in technical performance when specific digital algorithms were applied. Conclusions: This GC study highlights analytical concordance in PD-L1 testing among three major PD-L1 assays when TAP and CPS scoring algorithms are prospectively applied. Independently, DIA further supports the comparability of the technical performance of the assays. These observations support flexibility in cross-application of the different PD-L1 assays and scoring algorithms currently used to characterize PD-L1–positive GC samples.

Distribution characteristics and prognosis of tumor-infiltrating lymphocytes in the brain metastases of small cell lung cancer: a retrospective cohort study.

The efficacy of immunotherapy for brain metastases from small cell lung cancer (SCLC) is relatively low, and the tumor microenvironment of SCLC brain metastases is still unknown. Therefore, we investigated the distribution of tumor-infiltrating lymphocytes (TILs) and the expression of programmed cell death-ligand 1 (PD-L1) in patients with brain metastases from SCLC to explore the tumor microenvironment of SCLC brain metastases. A retrospective analysis was performed on 12 surgical specimens of brain metastases from patients with SCLC treated in the Department of Neurosurgery of The First Affiliated Hospital of Anhui Medical University from June 2017 to June 2022. The inclusion criteria for this study were the following: (I) a pathologically confirmed diagnosis of SCLC brain metastases; (II) surgical resection of brain metastases; (III) age >18 years; (IV) and complete clinical data. Patient-related data were retrieved from the inpatient medical record system, telephone follow-up of patients date of death, and overall survival (OS). The immunofluorescence-based tissue microenvironment analysis panel (MAP) was utilized for the detection of TILs, including CD3, CD8, programmed cell death 1 (PD-1), and PD-L1, in formalin-fixed and paraffin-embedded archival specimens of brain metastases. The expression levels of PD-L1 in tumor cells were detected by immunohistochemistry. The correlation between the OS and the above-mentioned markers was analyzed in the 12 patients. Twelve patients were included in the study. The patients' ages ranged from 51-78 years with a median of 68 years, with 1 female and 11 males. Among 12 patients with SCLC brain metastases: positive rates of CD3+ TILs in the tumor parenchyma vs. tumor stroma were 0.60%±0.94% vs. 1.76%±2.72% (P=0.01), respectively; positive rates of CD8+ TILs in the tumor parenchyma vs. tumor stroma were 0.80%±0.78% vs. 2.46%±3.72% (P=0.02), respectively. There was no co-expression of CD8+ and PD-1+ TILs in the tumor parenchyma of 11 cases, and the infiltration density of coexpressed CD3+ and PD-1+ TILs was more than 10/mm2 in only 1 case. There was no coexpression of CD3+ and PD-1+ TIL in the stroma of 10 cases, and the infiltration density of CD8+ and PD-1+ TILs was more than 10/mm2 in 2 cases. Immunohistochemistry was used to detect the expression of PD-L1 in 12 cases of SCLC metastatic lesions, and 3 cases (25%) were positive. Survival analysis showed that patients with positive intraepithelial CD3+ TILs had significantly longer OS [hazard ratio 3.383, 95% confidence interval (CI): 0.959-11.940; P=0.04]. Our study further demonstrated the immune microenvironment of SCLC brain metastases. The distribution of TILs in SCLC brain metastases is low and mainly distributed in the stroma, with the expression of PD-L1 in these tumor tissues being low. Further exploration of the immune microenvironment of SCLC brain metastases is of great significance for potential treatment.

Clinical outcomes and prognostic factors of concurrent chemoradiotherapy for anal squamous cell carcinoma in Japan.

Concurrent chemoradiotherapy (CCRT) is the standard treatment for locoregional anal squamous cell carcinoma (ASCC) in western countries. However, there have been few reports on the clinical outcomes of CCRT in Japan. This study aimed to evaluate the clinical outcomes of CCRT, prognostic factors, and the clinical impact of programmed cell death-ligand 1 (PD-L1) expression of ASCC in Japan. Patients with locoregional ASCC were enrolled between 2007 and 2017. All patients received CCRT consisting of ≥ 45Gy of radiation, 5-fluorouracil, and mitomycin C. Disease-free survival (DFS), overall survival (OS), and adverse events (AEs) were estimated. Expression of p16 and PD-L1 were assessed by immunohistochemical staining (IHC). This study included 36 patients, of whom 30 (83.3%) were female. Among the participants, 32 (88.9%) achieved complete clinical remission, while six (16.7%) experienced recurrence. The five-year DFS and five-year OS were 72.2% and 84.7%, respectively. Grades ≥ 3 serious AEs included neutropenia in 10 (27.7%) and perianal dermatitis in eight (22.2%). In a univariate analysis, male sex, lymph node metastasis, and large tumor size were significantly associated with worse outcome. In a multivariate analysis, tumor size was an independent factor associated with short DFS. Of the 30 patients whose biopsy specimens were available for IHC, 29 (96.7%) were positive for p16, and 13 (43.3%) were positive for PD-L1. However, PD-L1 expression did not show any clinical impact. The comparative etiology, clinical outcomes, and prognostic factors of CCRT observed in Japanese patients with locoregional ASCC were consistent with western data.

Molecular classification and biomarkers of outcome with immunotherapy in extensive-stage small-cell lung cancer: analyses of the CASPIAN phase 3 study

BackgroundWe explored potential predictive biomarkers of immunotherapy response in patients with extensive-stage small-cell lung cancer (ES-SCLC) treated with durvalumab (D) + tremelimumab (T) + etoposide-platinum (EP), D + EP, or EP in the randomized phase 3 CASPIAN trial.Methods805 treatment-naïve patients with ES-SCLC were randomized (1:1:1) to receive D + T + EP, D + EP, or EP. The primary endpoint was overall survival (OS). Patients were required to provide an archived tumor tissue block (or ≥ 15 newly cut unstained slides) at screening, if these samples existed. After assessment for programmed cell death ligand-1 expression and tissue tumor mutational burden, residual tissue was used for additional molecular profiling including by RNA sequencing and immunohistochemistry.ResultsIn 182 patients with transcriptional molecular subtyping, OS with D ± T + EP was numerically highest in the SCLC-inflamed subtype (n = 10, median 24.0 months). Patients derived benefit from immunotherapy across subtypes; thus, additional biomarkers were investigated. OS benefit with D ± T + EP versus EP was greater with high versus low CD8A expression/CD8 cell density by immunohistochemistry, but with no additional benefit with D + T + EP versus D + EP. OS benefit with D + T + EP versus D + EP was associated with high expression of CD4 (median 25.9 vs. 11.4 months) and antigen-presenting and processing machinery (25.9 vs. 14.6 months) and MHC I and II (23.6 vs. 17.3 months) gene signatures, and with higher MHC I expression by immunohistochemistry.ConclusionsThese findings demonstrate the tumor microenvironment is important in mediating better outcomes with D ± T + EP in ES-SCLC, with canonical immune markers associated with hypothesized immunotherapy mechanisms of action defining patient subsets that respond to D ± T.Trial registrationClinicalTrials.gov, NCT03043872.

Immune cell infiltration and inflammatory landscape in primary brain tumours

BackgroundPrimary malignant brain tumours are more than one-third of all brain tumours and despite the molecular investigation to identify cancer driver mutations, the current therapeutic options available are challenging due to high intratumour heterogeneity. In addition, an immunosuppressive and inflammatory tumour microenvironment strengthens cancer progression. Therefore, we defined an immune and inflammatory profiling of meningioma and glial tumours to elucidate the role of the immune infiltration in these cancer types.MethodsUsing tissue microarrays of 158 brain tumour samples, we assessed CD3, CD4, CD8, CD20, CD138, Granzyme B (GzmB), 5-Lipoxygenase (5-LOX), Programmed Death-Ligand 1 (PD-L1), O-6-Methylguanine-DNA Methyltransferase (MGMT) and Transglutaminase 2 (TG2) expression by immunohistochemistry (IHC). IHC results were correlated using a Spearman correlation matrix. Transcript expression, correlation, and overall survival (OS) analyses were evaluated using public datasets available on GEPIA2 in Glioblastoma (GBM) and Lower Grade Glioma (LGG) cohorts.ResultsSeven out of ten markers showed a significantly different IHC expression in at least one of the evaluated cohorts whereas CD3, CD4 and 5-LOX were differentially expressed between GBMs and astrocytomas. Correlation matrix analysis revealed that 5-LOX and GzmB expression were associated in both meningiomas and GBMs, whereas 5-LOX expression was significantly and positively correlated to TG2 in both meningioma and astrocytoma cohorts. These findings were confirmed with the correlation analysis of TCGA-GBM and LGG datasets. Profiling of mRNA levels indicated a significant increase in CD3 (CD3D, CD3E), and CD138 (SDC1) expression in GBM compared to control tissues. CD4 and 5-LOX (ALOX5) mRNA levels were significantly more expressed in tumour samples than in normal tissues in both GBM and LGG. In GBM cohort, GzmB (GZMB), SDC1 and MGMT gene expression predicted a poor overall survival (OS). Moreover, in LGG cohort, an increased expression of CD3 (CD3D, CD3E, CD3G), CD8 (CD8A), GZMB, CD20 (MS4A1), SDC1, PD-L1, ALOX5, and TG2 (TGM2) genes was associated with worse OS.ConclusionsOur data have revealed that there is a positive and significant correlation between the expression of 5-LOX and GzmB, both at RNA and protein level. Further evaluation is needed to understand the interplay of 5-LOX and immune infiltration in glioma progression.

Expression of PD-L1 (DAKO 28-8) in Urothelial Carcinoma of Urinary Bladder

Introduction: Around 90% of bladder cancers are urothelial carcinoma. Recent advancements in treatment have shifted towards targeted therapies, particularly immunotherapies targeting PD-L1 (Programmed Cell Death Ligand 1). PD-L1, a ligand for PD-1 receptors, helps cancer cells evade the immune system. Various factors, including genetic alterations, lead to its upregulation in cancer cells. Immunotherapies aim to block this pathway, making cancer cells more susceptible to the immune response. Objective: The study was designed to assess the frequency of PD-L1 expression by immunohistochemistry in urothelial carcinoma of urinary bladder and its association with histological grades. Methodology: This study was conducted at Department of Pathology, Pakistan Institute of Medical Sciences Islamabad. Fifty-six cases of urothelial carcinoma were included. Immunohistochemistry using PD-L1 Dako 28-8 clone was applied to prepared tissue sections. PD-L1 positivity was determined by brown membrane staining in tumor cells, scored using the Tumor Proportion Score (TPS). Results: The median patient age was 63±7 years, with the highest frequency (58.9%) of PD-L1 expression occurring in the age range of 56 to 65 years. However, there was no significant association between PD-L1 expression and age groups. Out of 56 cases, 64.3% had a TPS (Tumor Proportion Score) of ≥5%. Among the 76.7% high-grade cases, 72% had a TPS ≥5%, whereas 28% had a TPS <5%. Among the 23.2% low-grade cases, 61.5% had a TPS <5%, and 38.5% had a TPS ≥5%. Conclusion: Sixty-four percent urothelial carcinoma cases showed PD-L1 expression. Significant association (p value = 0.02) between PD-L1 expression and high-grade urothelial carcinoma was found using Pearson’s Chi-square test.

Tislelizumab plus chemotherapy versus placebo plus chemotherapy as first line treatment for advanced gastric or gastro-oesophageal junction adenocarcinoma: RATIONALE-305 randomised, double blind, phase 3 trial

ObjectiveTo evaluate the efficacy and safety of tislelizumab added to chemotherapy as first line (primary) treatment for advanced gastric or gastro-oesophageal junction adenocarcinoma compared with placebo plus chemotherapy.DesignRandomised, double blind,...

STAT3 Expression and Its Correlation with PD-L1 Expression in Non-Hodgkin's Lymphoma and Hodgkin's Lymphoma at Dr. Saiful Anwar Regional Public Hospital in Malang, Indonesian Population.

Lymphomas are malignant lymphocyte neoplasms that globally account for 10% of cancers in individuals aged <20 years. Malignant lymphomas are divided into Hodgkin's lymphoma (HL) and non-Hodgkin's lymphoma (NHL). Despite the availability of many therapeutic modalities for lymphoma, such as Brentuximab vedotin, Nivolumab, and Pembrolizumab, it is still necessary to identify appropriate strategies with minimal side effects. Immunotherapy is a promising approach, exemplified by targeting JAK/STAT3 signaling, which can inhibit tumor growth and enhance antitumor immune responses. Hence, STAT3 (signal transducer and activator of transcription 3) is a promising therapeutic target. PD-L1 (programmed death-ligand 1), an immune checkpoint molecule, is used as a frontline treatment for various cancers. This study aims to determine STAT3 expression and its correlation with PD-L1 expression in NHL and HL to serve as a basis for further research on anti-STAT3 and its combination with other therapy targets. Samples were obtained from paraffin blocks of patients with confirmed diagnoses of NHL and HL, and then immunohistochemical staining was carried out with PD-L1 and STAT3 antibodies. The collected data were then analyzed using SPSS. Among the 10 HL patients, no patients (0%) expressed STAT3, while nine patients (90%) expressed PD-L1. Among the 10 NHL patients, 1 patient (10%) expressed STAT3, while six patients (60%) expressed PD-L1. There were no significant differences in STAT3 expression and PD-L1 expression between HL patients and NHL patients. There was no correlation between STAT3 and PD-L1 expression in HL and NHL because almost all STAT3 expressions were negative. Although this study revealed no differences between STAT3 and PD-L1 expression in HL and NHL and no significant correlation between STAT3 and PD-L1 expression in HL and NHL, this may serve as the basis for understanding the role of STAT3 and PD-L1 in the regulation of HL and NHL, which may be useful for further research targeting STAT3 and PD-L1 immunotherapy in HL and NHL.

Sulforaphane impaired immune checkpoint blockade therapy through activating ΔNP63α/PD-L1 axis in gastric cancer.

Sulforaphane (SFN) exerts anticancer effect on various cancers including gastric cancer. However, the regulatory effect of SFN on programmed death-ligand 1 (PD-L1) and checkpoint blockade therapy in gastric cancer have not been elucidated. Here we demonstrated that SFN suppressed gastric cancer cell growth both in vitro and in vivo study. SFN upregulated PD-L1 expression through activating ΔNP63α in gastric cancer cells. Further, we found that SFN impaired the anticancer effect of anti-PD-L1 monoclonal antibody (α-PD-L1 mab) on gastric cancer cells. These results uncover a novel PD-L1 regulatory mechanism and the double-edged role of SFN in gastric cancer intervention.

Transcription Factor ETV4 Activates AURKA to Promote PD-L1 Expression and Mediate Immune Escape in Lung Adenocarcinoma

Introduction: The occurrence and progression of lung adenocarcinoma (LUAD) impair T-cell immune responses, causing immune escape and subsequently affecting the efficacy of immunotherapy in patients. Aurora kinase A (AURKA) is upregulated in varying cancers, but its role in LUAD immune escape is elusive. This work attempted to explore molecular mechanisms of AURKA regulation in LUAD immune escape. Methods: Through bioinformatics analysis, AURKA level in LUAD was evaluated, and potential upstream transcription factors of AURKA were predicted using hTFtarget. ETS variant transcription factor 4 (ETV4) expression in LUAD was analyzed through The Cancer Genome Atlas. Pearson’s correlation analysis was then utilized to test the correlation between AURKA and ETV4. Interaction and binding between AURKA and ETV4 were validated through dual-luciferase assay and chromatin immunoprecipitation. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) tested relative mRNA expression of AURKA and ETV4 in LUAD cells, cell counting kit-8 assayed cell viability, and Western blot analysis was conducted to determine the protein level of programmed death-ligand 1 (PD-L1). Coculture of LUAD cells with activated CD8+ T cells was carried out, and an LDH assay was used to assess the cytotoxicity of CD8+ T cells against LUAD cells. Interferon-γ (IFN-γ), interleukin-2 (IL-2), and tumor necrosis factor-α (TNF-α) levels in the coculture system were assessed by enzyme-linked immunosorbent assay (ELISA). Western blot assessed protein levels of JAK2, p-JAK2, STAT3, and p-STAT3. Results: Compared to normal tissues, AURKA and ETV4 were upregulated in tumor tissues, and AURKA presented a negative association with CD8+ T-cell immune infiltration but a positive association with PD-L1. qRT-PCR unveiled significantly upregulated mRNA of AURKA and ETV4 in LUAD cells compared to normal lung epithelial cells. Knockdown of AURKA significantly decreased cell viability and PD-L1 protein level in LUAD cells, enhanced cytotoxicity of CD8+ T cells against LUAD cells and IFN-γ, IL-2, and TNF-α expression, while overexpression of AURKA yielded opposite results. Furthermore, the knockdown of ETV4 could reverse the oncogenic characteristics of cells caused by AURKA overexpression. Conclusion: Our study illustrated that ETV4/AURKA axis promoted PD-L1 expression, suppressed CD8+ T-cell activity, and mediated immune escape in LUAD by regulating the JAK2/STAT3 signaling pathway.

TWIST1 Drives Cytotoxic CD8+ T-Cell Exhaustion through Transcriptional Activation of CD274 (PD-L1) Expression in Breast Cancer Cells.

In breast cancer, epithelial-mesenchymal transition (EMT) is positively associated with programmed death ligand 1 (PD-L1) expression and immune escape, and TWIST1 silences ERα expression and induces EMT and cancer metastasis. However, how TWIST1 regulates PD-L1 and immune evasion is unknown. This study analyzed TWIST1 and PD-L1 expression in breast cancers, investigated the mechanism for TWIST1 to regulate PD-L1 transcription, and assessed the effects of TWIST1 and PD-L1 in cancer cells on cytotoxic CD8+ T cells. Interestingly, TWIST1 expression is correlated with high-level PD-L1 expression in ERα-negative breast cancer cells. The overexpression and knockdown of TWIST1 robustly upregulate and downregulate PD-L1 expression, respectively. TWIST1 binds to the PD-L1 promoter and recruits the TIP60 acetyltransferase complex in a BRD8-dependent manner to transcriptionally activate PD-L1 expression, which significantly accelerates the exhaustion and death of the cytotoxic CD8+ T cells. Accordingly, knockdown of TWIST1 or BRD8 or inhibition of PD-L1 significantly enhances the tumor antigen-specific CD8+ T cells to suppress the growth of breast cancer cells. These results demonstrate that TWIST1 directly induces PD-L1 expression in ERα-negative breast cancer cells to promote immune evasion. Targeting TWIST1, BRD8, and/or PD-L1 in ERα-negative breast cancer cells with TWIST1 expression may sensitize CD8+ T-cell-mediated immunotherapy.

Detection of PD‑L1 expression and epithelial‑mesenchymal transition of circulating tumor cells in non‑small cell lung cancer.

The present study aimed to assess the roles of peripheral circulating tumor cell (CTC) count, CTC subtypes and programmed death ligand 1 (PD-L1) expression in the clinical staging and prognosis of patients with non-small cell lung cancer (NSCLC). A total of 100 patients with NSCLC with available tumor tissues were enrolled in the present study, and 7.5 ml peripheral blood was collected. Patients were divided into PD-L1-positive and PD-L1-negative groups according to PD-L1 immunohistochemical staining. Peripheral blood samples from both groups were analyzed to determine the CTC count, epithelial-type CTCs (E-CTCs), mesenchymal-type CTCs (M-CTCs) and PD-L1 expression. Clinical data were collected, and patients were followed up for a maximum of 36 months, with patient death as the endpoint event. Patients with PD-L1-positive tumors had a worse prognosis compared with those with PD-L1-negative tumors (P=0.045). The PD-L1-positive group exhibited significantly higher numbers of CTCs and M-CTCs compared with the PD-L1-negative group (P≤0.05). However, the number of E-CTCs did not differ significantly between the two groups (P>0.05). PD-L1-positive patients with higher CTC and M-CTC counts had relatively poorer prognoses (P≤0.05), while the number of E-CTCs had no significant effect on prognosis (P>0.05). Compared with the early-stage NSCLC group, the late-stage NSCLC group exhibited a significant increase in the CTC count (P≤0.05), while E-CTC and M-CTC counts did not significantly differ between the two groups (P>0.05). The PD-L1-positive group exhibited a significant increase in the number of PD-L1+ CTCs and PD-L1+ M-CTCs compared with the PD-L1-negative group (P≤0.05), while PD-L1+ E-CTC counts did not differ significantly between the two groups (P>0.05). The PD-L1-positive patients with a higher number of PD-L1+ CTCs and PD-L1+ M-CTCs had relatively poorer prognoses (P≤0.05), while the PD-L1+ E-CTC count had no significant effect on prognosis (P>0.05). Compared with the early-stage NSCLC group, the late-stage NSCLC group exhibited a significant increase in the number of PD-L1+ CTCs and PD-L1+ M-CTCs (P≤0.05), while PD-L1+ E-CTC counts did not significantly differ between the two groups (P>0.05). Based on univariate and multivariate analyses, the number of PD-L1+ M-CTCs was identified as an independent prognostic factor for NSCLC. In conclusion, the presence of CTCs in peripheral blood, particularly PD-L1+ M-CTC subtype, indicated poorer clinical staging and prognosis in patients with NSCLC. These findings suggested that CTCs, specifically the PD-L1+ M-CTC subtype, could serve as a monitoring indicator for the clinical staging and prognosis of patients with NSCLC.

Association of PD-L1 expression and clinical outcomes in ROS1 - rearranged advanced non-small cell lung cancer treated with crizotinib.

Programmed cell death ligand 1 (PD-L1) is more readily expressed in ROS proto-oncogene 1 (ROS1) rearranged non-small cell lung cancer (NSCLC) compared to NSCLC cases lacking driver gene mutations. Prior research has established a link between PD-L1 expression and reduced effectiveness of EGFR or ALK inhibitors in EGFR or ALK-positive NSCLC. Nonetheless, the relationship between initial PD-L1 levels and the clinical impact of first-line crizotinib therapy in ROS1-rearranged NSCLC is still uncertain. From January 2016 to December 2021, a total of 246 patients with ROS1 positive tumors were collected. Out of these, 82 patients with advanced ROS1-rearranged NSCLC, who were treated with crizotinib as their initial therapy, were selected for the study. The study aimed primarily to evaluate the objective response rate (ORR) and progression-free survival (PFS), and secondarily to assess disease control rate (DCR) and overall survival (OS). Of the 82 advanced ROS1-rearranged NSCLC patients, 38 exhibited PD-L1 positivity, subdivided into 11 with high and 27 with low expression levels, while the remaining 44 showed no PD-L1 expression. The ORR for all included patients was 80.5%. No statistically significant variance in ORR was observed among ROS1-rearranged NSCLC patients across differing PD-L1 expression statuses. However, there was a statistically significant difference in DCR between PD-L1 negative group (100%) and high expression group (90.9%) (p=0.04). The median PFS spanned 26.4 months for the PD-L1 negative group, 16.6 for the low expression group, and 13.7 for the high expression group (p=0.001). Additionally, a notable statistical disparity was also observed in median PFS between the PD-L1 negative and positive groups (p=0.02). For the entire study population, the median OS was 53.0 months (95% CI 43.8 - 62.2). In the PD-L1-negative group, the median OS reached 57.2 months, compared to 53.0 months in the PD-L1-positive group, a difference lacking statistical significance (p=0.43). Our results suggest that for ROS1-positive NSCLC patients receiving crizotinib as first-line therapy, PD-L1 expression may serve as a negative prognostic marker for PFS rather than OS.

Treg-derived TGF-β1 dampens cGAS-STING signaling to downregulate the expression of class I MHC complex in multiple myeloma

Multiple myeloma (MM) progression involves diminished tumor antigen presentation and an immunosuppressive microenvironment, characterized by diminished expression of major histocompatibility complexes (MHC) class I molecule and elevated programmed death ligand 1 (PDL1) in MM cells, along with an enriched population of regulatory T cells (Tregs). To investigate Treg's influence on MM cells, we established a co-culture system using Tregs from MM patients and the MM cell lines (MM.1S and SK-MM-1) in vitro and assessed the effects of intervening in the relevant pathways connecting Tregs and MM cells in vivo. In vitro, Tregs induced transforming growth factor beta-1 (TGF-β1) production, downregulated MHC I members, and increased PDL1 expression in MM cells. Treg-derived TGF-β1 suppressed the cGAS-STING pathway, contributing to the loss of MHC I molecule expression and PDL1 upregulation. Correspondingly, neutralizing TGF-β1 or activating the cGAS-STING pathway restored MHC I and PDL1 expression, effectively countering the pro-tumorigenic effect of Tregs on MM cells in vivo. These data elucidated how Tregs influence tumor antigen presentation and immunosuppressive signal in MM cells, potentially providing therapeutic strategies, such as neutralizing TGF-β1 or activating the cGAS-STING pathway, to address the immune escape and immunosuppressive dynamics in MM.

Dual neutrophil subsets exacerbate or suppress inflammation in tuberculosis via IL-1β or PD-L1.

Neutrophils can be beneficial or deleterious during tuberculosis (TB). Based on the expression of MHC-II and programmed death ligand 1 (PD-L1), we distinguished two functionally and transcriptionally distinct neutrophil subsets in the lungs of mice infected with mycobacteria. Inflammatory [MHC-II-, PD-L1lo] neutrophils produced inflammasome-dependent IL-1β in the lungs in response to virulent mycobacteria and "accelerated" deleterious inflammation, which was highly exacerbated in IFN-γR-/- mice. Regulatory [MHC-II+, PD-L1hi] neutrophils "brake" inflammation by suppressing T-cell proliferation and IFN-γ production. Such beneficial regulation, which depends on PD-L1, is controlled by IFN-γR signaling in neutrophils. The hypervirulent HN878 strain from the Beijing genotype curbed PD-L1 expression by regulatory neutrophils, abolishing the braking function and driving deleterious hyperinflammation in the lungs. These findings add a layer of complexity to the roles played by neutrophils in TB and may explain the reactivation of this disease observed in cancer patients treated with anti-PD-L1.

Reduced Tolerogenic Program Death-Ligand 1-Expressing Conventional Type 1 Dendritic Cells Are Associated with Rapid Decline in Chronic Obstructive Pulmonary Disease.

Chronic obstructive pulmonary disease (COPD) is characterized, at least in part, by autoimmunity through amplified T helper 1 and 17 (Th1 and Th17) immune responses. The loss of immune tolerance controlled by programmed death-ligand 1 (PD-L1) may contribute to this. We studied the tolerogenic role of PD-L1+ dendritic cells (DCs) and their subtypes in relation to specific T cell immunity and the clinical phenotypes of COPD. We used flow cytometry to analyze PD-L1 expression by the DCs and their subtypes in the peripheral blood mononuclear cells (PBMCs) from normal participants and those with COPD. T cell proliferation and the signature cytokines of T cell subtypes stimulated with elastin as autoantigens were measured using flow cytometry and enzyme-linked immunosorbent assays (ELISA), respectively. A total of 83 participants were enrolled (normal, n = 29; COPD, n = 54). A reduced PD-L1+ conventional dendritic cell 1 (cDC1) ratio in the PBMCs of the patients with COPD was shown (13.7 ± 13.7%, p = 0.03). The decrease in the PD-L1+ cDC1 ratio was associated with a rapid decline in COPD (p = 0.02) and correlated with the CD4+ T cells (r = -0.33, p = 0.02). This is supported by the NCBI GEO database accession number GSE56766, the researchers of which found that the gene expressions of PD-L1 and CD4, but not CD8 were negatively correlated from PBMC in COPD patients (r = -0.43, p = 0.002). Functionally, the PD-L1 blockade enhanced CD4+ T cell proliferation stimulated by CD3/elastin (31.2 ± 22.3%, p = 0.04) and interleukin (IL)-17A production stimulated by both CD3 (156.3 ± 54.7, p = 0.03) and CD3/elastin (148 ± 64.9, p = 0.03) from the normal PBMCs. The PD-L1 blockade failed to increase IL-17A production in the cDC1-depleted PBMCs. By contrast, there was no significant change in interferon (IFN)-γ, IL-4, or IL-10 after the PD-L1 blockade. Again, these findings were supported by the NCBI GEO database accession number GSE56766, the researchers of which found that only the expression of RORC, a master transcription factor driving the Th17 cells, was significantly negatively correlated to PD-L1 (r = -0.33, p = 0.02). Circulating PD-L1+ cDC1 was reduced in the patients with COPD, and the tolerogenic role was suppressed with susceptibility to self-antigens and linked to rapid decline caused by Th17-skewed chronic inflammation.

Exploratory biomarker analysis in the phase III L-MOCA study of olaparib maintenance therapy in patients with platinum-sensitive relapsed ovarian cancer.

The prospective phase III multi-centre L-MOCA trial (NCT03534453) has demonstrated the encouraging efficacy and manageable safety profile of olaparib maintenance therapy in the Asian (mainly Chinese) patients with platinum-sensitive relapsed ovarian cancer (PSROC). In this study, we report the preplanned exploratory biomarker analysis of the L-MOCA trial, which investigated the effects of homologous recombination deficiency (HRD) and programmed cell death ligand 1 (PD-L1) expression on olaparib efficacy. HRD status was determined using the ACTHRD assay, an enrichment-based targeted next-generation sequencing assay. PD-L1 expression was assessed by SP263 immunohistochemistry assay. PD-L1 expression positivity was defined by the PD-L1 expression on ≥ 1% of immune cells. Kaplan-Meier method was utilised to analyse progression-free survival (PFS). This exploratory biomarker analysis included 225 patients and tested HRD status [N = 190; positive, N = 125 (65.8%)], PD-L1 expression [N = 196; positive, N = 56 (28.6%)], and BRCA1/2 mutation status (N = 219). The HRD-positive patients displayed greater median PFS than the HRD-negative patients [17.9 months (95% CI: 14.5-22.1) versus 9.2 months (95% CI: 7.5-13.8)]. PD-L1 was predominantly expressed on immune cells. Positive PD-L1 expression on immune cells was associated with shortened median PFS in the patients with germline BRCA1/2 mutations [14.5 months (95% CI: 7.4-18.2) versus 22.2 months (95% CI: 18.3-NA)]. Conversely, positive PD-L1 expression on immune cells wasassociated with prolonged median PFS in the patients with wild-type BRCA1/2 [20.9 months (95% CI: 13.9-NA) versus 8.3 months (95% CI: 6.7-13.8)]. HRD remained an effective biomarker for enhanced olaparib efficacy in the Asian patients with PSROC. Positive PD-L1 expression was associated with decreased olaparib efficacy in the patients with germline BRCA1/2 mutations but associated with improved olaparib efficacy in the patients with wild-type BRCA1/2. NCT03534453. Registered at May 23, 2018.