Programmed Death-ligand 1 Expression In Tumor Cells Research Articles

Analysis of disease-free survival in CheckMate 274 by PD-L1 combined positive score and tumor proportion score.

491 Background: CheckMate 274 demonstrated a significant improvement in disease-free survival (DFS) with nivolumab (NIVO) versus placebo (PBO) both in the intent-to-treat population (hazard ratio [HR], 0.70; 98.22% confidence interval [CI], 0.55–0.90; P < 0.001) and in patients (pts) with tumor programmed death ligand 1 (PD-L1) expression ≥ 1% assessed by the tumor proportion score (TPS) (HR, 0.55; 98.72% CI, 0.35–0.85; P < 0.001). An exploratory subgroup analysis showed a trend toward a DFS benefit with NIVO in pts with TPS < 1% (0.82; 95% CI, 0.63–1.06). To further characterize the relationship between PD-L1 expression and NIVO efficacy, we report an analysis of DFS based on PD-L1 expression in both tumor and immune cells using the combined positive score (CPS). Methods: CheckMate 274 is a phase 3, randomized, double-blind, multicenter trial of NIVO versus PBO in pts with high-risk muscle-invasive urothelial carcinoma after radical surgery. Pts were randomized 1:1 to NIVO 240 mg or PBO every 2 weeks intravenously for 1 year of adjuvant treatment. The primary endpoints of the study are DFS in the intent-to-treat population and in pts with TPS ≥ 1%. The Dako PD-L1 IHC 28-8 pharmDx assay was used to evaluate TPS. CPS was determined retrospectively from previously stained immunohistochemistry slides using the CPS algorithm. CPS was calculated as the number of both PD-L1 positive tumor and immune cells divided by the number of viable tumor cells in the evaluable tumor area, multiplied by 100; TPS was similarly calculated with the number of PD-L1 positive tumor cells as the numerator. This analysis only included pts with both quantifiable CPS and TPS. Results: Of the 629 pts with quantifiable TPS and CPS, 249 (40%) had TPS ≥ 1% (NIVO, n = 124; PBO, n = 125), 380 (60%) had TPS < 1% (NIVO, n = 191; PBO, n = 189), 557 (89%) had CPS ≥ 1 (NIVO, n = 281; PBO, n = 276), and 72 (11%) had CPS < 1 (NIVO, n = 34; PBO, n = 38). Within TPS < 1% pts, 81% (n = 309) had CPS ≥ 1. The number of pts and the DFS outcomes in pts with TPS ≥ 1% and CPS ≥ 1 are shown in the Table. In pts with TPS < 1% who also had CPS ≥ 1, median DFS (95% CI) was 19.2 (15.6–33.4) months with NIVO versus 10.1 (8.2–19.4) months with PBO. The HR for NIVO versus PBO in these pts was 0.73 (95% CI, 0.54–0.99). Conclusions: This exploratory analysis of PD-L1 expression by CPS showed a higher proportion of pts with CPS ≥ 1 than TPS ≥ 1%, and that most pts with TPS < 1% had CPS ≥ 1. In the CPS ≥ 1 subgroup, median DFS with NIVO was more than double that with placebo. These results support the conclusion that pts with TPS < 1% also benefit from adjuvant NIVO. Clinical trial information: NCT02632409. [Table: see text]

Decreased Expression of Programmed Death Ligand-L1 by Seven in Absentia Homolog 2 in Cholangiocarcinoma Enhances T-Cell-Mediated Antitumor Activity.

N6-methyladenosine (m6A) has been reported as an important mechanism of post-transcriptional regulation. Programmed death ligand 1 (PD-L1) is a primary immune inhibitory molecule expressed on tumor cells that promotes immune evasion. In addition, seven in absentia homolog 2 (Siah2), a RING E3 ubiquitin ligase, has been involved in tumorigenesis and cancer progression. However, the role of m6A-METTL14-Siah2-PD-L1 axis in immunotherapy remains to be elucidated. In this study, we showed that METTL14, a component of the m6A methyltransferase complex, induced Siah2 expression in cholangiocarcinoma (CCA). METTL14 was shown to enrich m6A modifications in the 3’UTR region of the Siah2 mRNA, thereby promoting its degradation in an YTHDF2-dependent manner. Furthermore, co-immunoprecipitation experiments demonstrated that Siah2 interacted with PD-L1 by promoting its K63-linked ubiquitination. We also observed that in vitro and in vivo Siah2 knockdown inhibited T cells expansion and cytotoxicity by sustaining tumor cell PD-L1 expression. The METTL14-Siah2-PD-L1–regulating axis was further confirmed in human CCA specimens. Analysis of specimens from patients receiving anti-PD1 immunotherapy suggested that tumors with low Siah2 levels were more sensitive to anti-PD1 immunotherapy. Taken together, our results evidenced a new regulatory mechanism of Siah2 by METTL14-induced mRNA epigenetic modification and the potential role of Siah2 in cancer immunotherapy.

High programmed death ligand 1 expression in carcinomatous components predicts a poor prognosis in pulmonary pleomorphic carcinoma

This study reviewed the clinicopathological characteristics and programmed death ligand 1 (PD-L1) expression of 46 patients with pulmonary pleomorphic carcinoma to better understand its clinical behavior and factors affecting the survival. Data of patients with pulmonary pleomorphic carcinomas resected in our institution were retrospectively reviewed. The tumors were classified as carcinomatous or sarcomatous according to the tissue components. Pathological characteristics were evaluated on hematoxylin and eosin-stained sections. The percentages of tumor cells with membrane staining for PD-L1 in carcinomatous and sarcomatous components were determined. We reviewed data of 46 patients (41 males, 5 females; median age 70.5years old, range 36-83years old). Most patients with pulmonary pleomorphic carcinoma expressed PD-L1 (80.4%), and the proportion of PD-L1 expression in tumor cells was significantly higher in sarcomatous components than in carcinomatous components. In univariable analyses, high p-stage (III), necrosis on pathological findings, and high PD-L1 expression in carcinomatous components (≥ 50%) were poor prognostic factors for the overall survival. In multivariable analyses, high PD-L1 expression in carcinomatous components was significantly associated with a poor prognosis after surgery. High PD-L1 expression in carcinomatous components was significantly associated with a poor prognosis after surgery.

Nintedanib enhances the efficacy of PD-L1 blockade by upregulating MHC-I and PD-L1 expression in tumor cells.

Background: Immune checkpoint inhibitors (ICIs), such as programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1), have been widely applied in clinical and scientific research. Despite their effective antitumor effects in clinical tumor therapy, most tumors are still resistant to ICIs and long-term benefits are lacking. In addition, tumor patients complicated with interstitial lung disease limit the application of ICI therapy. Therefore, for these cases, there is an urgent need to develop new methods to relieve lung complications and enhance the efficacy of ICI therapy. Nintedanib, a potent triple angiokinase inhibitor approved for the treatment of progressive fibrotic interstitial lung disease. However, its immunotherapy synergy properties and mechanism are still pending further exploration.Methods: To explore the therapeutic potential of nintedanib and αPD-L1 combination therapy, MC38, LLC, and 4T1 tumor models were used to investigate antitumor and antimetastatic activities in vivo. An idiopathic pulmonary fibrosis-tumor bearing model was used to evaluate the effect of the synergy therapy on tumor model complicated with lung disease. Moreover, RNA-seq, immunohistochemistry, and flow cytometry were utilized to analyze the effect of combination treatment on the tumor microenvironment. The bioactivity following different treatments was determined by western blotting, CCK-8, and flow cytometry.Results: In this study, nintedanib and αPD-L1 synergy therapy exhibited significant antitumor, antimetastatic and anti-pulmonary fibrosis effects. Both in vitro and in vivo experiments revealed that these effects included promoting vessel normalization, increasing infiltration and activation of immune cells in tumors, enhancing the response of interferon-gamma, and activating the MHC class I-mediated antigen presentation process. Moreover, our results showed an increased expression of PD-L1 and promoted phosphorylation of STAT3 after nintedanib (1 µM) treatment.Conclusion: The combination of nintedanib and αPD-L1 increased ICI therapy responses, relieved lung complications and further activated the tumor immune microenvironment; thus, exhibiting a notable antitumor effect. Accordingly, the nintedanib synergy strategy is expected to be a promising candidate therapy for tumor patients complicated with interstitial lung disease in clinical practice.

TSH-TSHR axis promotes tumor immune evasion

BackgroundHormones are identified as key biological variables in tumor immunity. However, previous researches mainly focused on the immune effect of steroid hormones, while the roles that thyroid-stimulating hormone (TSH) played...

Optimizing Immuno-PET Imaging of Tumor PD-L1 Expression: Pharmacokinetic, Biodistribution, and Dosimetric Comparisons of 89Zr-Labeled Anti-PD-L1 Antibody Formats.

PET imaging of programmed cell death ligand 1 (PD-L1) may help to noninvasively predict and monitor responses to anti-programmed cell death 1/anti-PD-L1 immunotherapies. In this study, we compared the imaging characteristics of 3 radioligands derived from the anti-PD-L1 IgG1 complement 4 (C4). In addition to the IgG C4, we produced a fragment antigen-binding (Fab) C4, as well as a double-mutant IgG C4 (H310A/H435Q) with minimal affinity for the murine neonatal Fc receptor. Methods: The pharmacokinetics, biodistribution, and dosimetry of the 3 89Zr-labeled C4 ligands were compared by longitudinal PET/CT imaging in nude mice bearing subcutaneous human non-small cell lung cancer xenografts with positive (H1975 model) or negative (A549 model) endogenous PD-L1 expression. Results: The C4 radioligands substantially accumulated in PD-L1-positive tumors but not in PD-L1-negative tumors or in blocked PD-L1-positive tumors, confirming their PD-L1-specific tumor targeting. 89Zr-Fab C4 and 89Zr-IgG C4 (H310A/H435Q) were rapidly eliminated compared with 89Zr-IgG C4. Consequently, maximal tumor-to-muscle ratios were obtained earlier, at 4 h after injection for 89Zr-Fab C4 (ratio, ∼6) and 24 h after injection for 89Zr-IgG C4 (H310A/H435Q) (ratio, ∼9), versus 48 h after injection for 89Zr-IgG C4 (ratio, ∼8). Background activity in nontumor tissues was low, except for high kidney retention of 89Zr-Fab C4 and persistent liver accumulation of 89Zr-IgG C4 (H310A/H435Q) compared with 89Zr-IgG C4. Dosimetry estimates suggested that the C4 radioligands would yield organ-absorbed doses tolerable for repeated clinical PET imaging studies. Conclusion: This study highlights the potential of designing radioligands with shorter pharmacokinetics for PD-L1 immuno-PET imaging in a preclinical model and encourages further clinical translation of such radioligands.

Efficacy, safety, and biomarker analysis of Camrelizumab in Previously Treated Recurrent or Metastatic Nasopharyngeal Carcinoma (CAPTAIN study)

BackgroundThis study aimed to evaluate the antitumor activity of camrelizumab, an antiprogrammed cell death-1 antibody, in pretreated recurrent or metastatic nasopharyngeal carcinoma (NPC) and to explore predictive biomarkers.MethodsPatients with recurrent...

The Expression of Programmed Death Ligand 1 and Vimentin in Resected Non-Metastatic Non-Small-Cell Lung Cancer: Interplay and Prognostic Effects.

Programmed death ligand 1 (PD-L1) is an immune checkpoint with a role in cancer-related immune evasion. It is a target for cancer immunotherapy and its expression is detected for the use of some immune checkpoint inhibitors in advanced non-small cell lung cancer patients (NSCLC). Vimentin is a key component of the epithelial-to-mesenchymal transition phenotype. Its expression has negative prognostic effects in NSCLC. In this study, we retrospectively evaluated PD-L1 and vimentin expression in tumor cells, immune infiltrate and PD-L1 positive immune infiltrate via immunohistochemistry in tissue samples from resected non-metastatic NSCLC patients. We explored the interplay between PD-L1 and vimentin expression through Spearman’s correlation test. We performed univariate analysis through the Cox models for demographic and clinico-pathological variables, and also for dichotomized biomarkers, i.e., PD-L1 and vimentin in tumor cells, both with 1 and 50% cutoffs. We used Kaplan-Meier method to estimate the overall survival, comparing both vimentin and PD-L1 positive patients with all the others. We found a weak positive correlation between PD-L1 and vimentin expressions in tumor cells (r = 0.25; p = 0.001). We also observed a statistically not significant trend towards a shorter overall survival in patients with both PD-L1 and vimentin expression >1% (HR = 1.36; 95% CI: 0.96–1.93, p = 0.087). In conclusion, these findings suggest that interplay between PD-L1 and vimentin may exist in non-metastatic NSCLC patients and the positivity of both markers in tumor tissue is associated with a trend towards a worse prognosis.

Expression of PD-L1 and BRCA1 in Triple-Negative Breast Cancer Patients and Relationship with Clinicopathological Characteristics.

Objective To study the expression of programmed cell death ligand-1 (PD-L1) and breast cancer susceptibility gene 1 (BRCA1) in triple-negative breast cancer (TNBC) patients and analyze their relationship with clinicopathological characteristics. Methods 76 TNBC tissues were collected as the research object, while 60 adjacent tissues were used as controls. All patients underwent surgical treatment, and the expression of PD-L1 and BRCA1 in cancer tissues and adjacent tissues was detected by immunohistochemistry. At the same time, the relationship between PD-L1, BRCA1, and clinicopathological characteristics of patients with TNBC (including patient age, menopausal status, tumor size, lymph node metastasis, histological grade, Ki-67 expression, and p53 expression) were analyzed by univariate and logistic multivariate analysis. Results The positive expression rate of PD-L1 in the TNBC group was 64.47%, which was higher than the control group by 41.67%. The positive expression rate of BRCA1 was 27.63%, which was lower than the control group by 48.33%. PD-L1 expression has no significant relationship with age, menopausal status, and p53 expression in TNBC patients. TNBC patients with tumors ≥2 cm, histological grade III, lymph node metastasis, and Ki-67 expression ≥20% had higher PD-L1 positive expression rates. The tumor size, Ki-67 expression, and PD-L1 expression of TNBC patients have independent effects. The expression of BRCA1 has no significant relationship with menopausal status, tumor size, Ki-67 expression, etc. TNBC patients with age <45 years, histological grade I or II, no lymph node metastasis, and high p53 expression positive rate had higher BRCA1 positive expression rate. The age of TNBC patients, p53 expression, and BRCA1 expression have independent effects. Conclusion In TNBC cancer tissues, there is a high expression of PD-L1 and low expression of BRAC1. The tumor size, Ki-67 expression, and PD-L1 expression of TNBC patients have independent effects. The age of TNBC patients, p53 expression, and BRCA1 expression have independent effects.

The Role of Oncogenes and Redox Signaling in the Regulation of PD-L1 in Cancer.

Simple SummaryPD-L1 is an important immune checkpoint molecule that is expressed in cancer tissues at various levels and plays a major role in tumor evasion from immune system. Therefore, understanding the mechanisms by which PD-L1 expression is regulated in tumor environment is important for the design of new therapeutic strategies to overcome tumor immune escape and improve the outcome of cancer treatment. Recent studies suggest that genetic, epigenetic, and transcriptional factors as well as posttranscriptional and posttranslational processes are crucial regulators of PD-L1 expression in tumor cells. This review focuses on two newly described regulations of PD-L1 mediated by oncogenes, and redox homeostasis. In this context, a recent research work describes the important role of oncogenic K-ras, growth factor receptors (FGFR1 and EGFR) and ROS in regulating PD-L1 expression in pancreatic cancer cells and aids significant new mechanistic insights in this important area.Tumor cells can evade the immune system via multiple mechanisms, including the dysregulation of the immune checkpoint signaling. These signaling molecules are important factors that can either stimulate or inhibit tumor immune response. Under normal physiological conditions, the interaction between programmed cell death ligand 1 (PD-L1) and its receptor, programmed cell death 1 (PD-1), negatively regulates T cell function. In cancer cells, high expression of PD-L1 plays a key role in cancer evasion of the immune surveillance and seems to be correlated with clinical response to immunotherapy. As such, it is important to understand various mechanisms by which PD-L1 is regulated. In this review article, we provide an up-to-date review of the different mechanisms that regulate PD-L1 expression in cancer. We will focus on the roles of oncogenic signals (c-Myc, EML4-ALK, K-ras and p53 mutants), growth factor receptors (EGFR and FGFR), and redox signaling in the regulation of PD-L1 expression and discuss their clinical relevance and therapeutic implications. These oncogenic signalings have common and distinct regulatory mechanisms and can also cooperatively control tumor PD-L1 expression. Finally, strategies to target PD-L1 expression in tumor microenvironment including combination therapies will be also discussed.

Human Vγ9Vδ2 T cells exert anti-tumor activity independently of PD-L1 expression in tumor cells

Human γδ T cells expressing Vγ9Vδ2 T cell receptors play a crucial role in the innate immune system and have an attracted interest as effector cells in adoptive cellular immunotherapy. However, the efficacy of adoptive cellular immunotherapy for the treatment of tumors requires overcoming the immunosuppressive microenvironment. αβ T cell inhibition in the tumor microenvironment is associated with programmed death-ligand 1 (PD-L1) expression level. Vγ9Vδ2 T cells (abbreviated as γδ T cells here) exert potent cytotoxic effects in various cancers; however, γδ T cell activity in relation to the level of PD-L1 expression in cancer cells remains unclear, and the association between the PD-1/PD-L1 axis and γδ T cell cytotoxicity needs to be investigated. In this study, PD-1 blockade did not increase the cytotoxicity of γδ T cells against PD-L1high cancer cells. However, the anti-PD-L1 monoclonal antibody (mAb) enhanced the cytotoxicity of γδ T cells against a subset of cancer cells, whereas PD-L1 knockdown did not increase the cytotoxicity of γδ T cells. We also found that the expression levels of PD-L1 were positively correlated with the changes of γδ T cells cytotoxicity induced by anti-PD-L1 mAb. These observations suggest that anti-PD-L1 mAb treatment adds ADCC activity to the cytotoxicity of γδ T cells itself against PD-L1high cancer cells. The present results suggest that ex vivo expanded γδ T cells have antitumor activity independently of PD-L1 expression and may be promising effector cells for γδ T cell immunotherapy.

THADA drives Golgi residency and upregulation of PD-L1 in cancer cells and provides promising target for immunotherapy

BackgroundThe abnormal upregulation of programmed death-ligand 1 (PD-L1) in cancer cells inhibits T cell-mediated cytotoxicity, but the molecular mechanisms that drive and maintain PD-L1 expression are still incompletely understood.MethodsCombined analyses...

A retrospective analysis of eleven gene mutations, PD-L1 expression and clinicopathological characteristics in non-small cell lung cancer patients

ObjectivesTo investigate the associations among expression of programmed cell death ligand 1 (PD-L1), eleven mutated genes, and clinicopathological characteristics in 273 patients with non-small cell lung cancer (NSCLC). MethodsWe retrospectively examined tumor PD-L1 expression in 247 surgically resected primary and 26 advanced NSCLC patients by immunohistochemistry using SP263 antibody assay. Gene mutations of EGFR, TP53, KRAS, PIK3CA, ERBB2, MET, RET, ALK, BRAF, ROS1, and APC were examined by NGS sequence. Data analysis was carried out using SPSS 22.0. The associations among PD-L1 expression, eleven mutated genes and clinicopathological characteristics were assessed by univariate and multivariate analysis. ResultsAmong the total 273 patients, 68 (24.9%) patients were positive for PD-L1 expression. Data showed that mutated rate of EGFR gene was the highest with 63.0% (172/273), followed by TP53 (11.7%, 32/273) and KRAS (5.5%, 15/273). The female, non-smoker, and patients with adenocarcinoma (ADC) were more likely to have EGFR mutations. Multivariate logistic regression showed that PD-L1 expression was significantly associated with Non-ADC, lymphatic invasion, EGFR wild type and TP53 mutation (p = 0.041, <0.001, 0.004 and 0.014, respectively). Moreover, PD-L1 expression in adenocarcinoma was associated with lymphatic invasion, mutation of TP53 and KRAS gene (p = 0.012, <0.025 and 0.041, respectively). ConclusionsMutations of EGFR, KRAS and TP53 should be routinely detected in clinical practice to better guide the immunotherapy for NSCLC patients. Future investigations are warranted to illustrate the potential mechanisms between driver mutations and PD-L1 expression for guiding immunotherapy in patients with NSCLC.

M6A Demethylase ALKBH5 Regulates PD-L1 Expression and Tumor Immunoenvironment in Intrahepatic Cholangiocarcinoma.

N6-methyladenosine (m6A) has been reported as an important mechanism of posttranscriptional regulation. Programmed death-ligand 1 (PD-L1) is a primary immune inhibitory molecule expressed on tumor cells that promotes immune evasion. Here we report ALKBH5 as an important m6A demethylase that orchestrates PD-L1 expression in intrahepatic cholangiocarcinoma (ICC). Regulation of PD-L1 expression by ALKBH5 was confirmed in human ICC cell lines. Sequencing of the m6A methylome identified PD-L1 mRNA as a direct target of m6A modification whose levels were regulated by ALKBH5. Furthermore, ALKBH5 and PD-L1 mRNA were shown to interact. ALKBH5 deficiency enriched m6A modification in the 3'UTR region of PD-L1 mRNA, thereby promoting its degradation in a YTHDF2-dependent manner. In vitro and in vivo, tumor-intrinsic ALKBH5 inhibited the expansion and cytotoxicity of T cells by sustaining tumor cell PD-L1 expression. The ALKBH5-PD-L1-regulating axis was further confirmed in human ICC specimens. Single-cell mass cytometry analysis unveiled a complex role of ALKBH5 in the tumor immune microenvironment by promoting the expression of PD-L1 on monocytes/macrophages and decreasing the infiltration of myeloid-derived suppressor-like cells. Analysis of specimens from patients receiving anti-PD1 immunotherapy suggested that tumors with strong nuclear expression patterns of ALKBH5 are more sensitive to anti-PD1 immunotherapy. Collectively, these results describe a new regulatory mechanism of PD-L1 by mRNA epigenetic modification by ALKBH5 and the potential role of ALKBH5 in immunotherapy response, which might provide insights for cancer immunotherapies. SIGNIFICANCE: This study identifies PD-L1 mRNA as a target of ALKBH5 and reveals a role for ALKBH5 in regulating the tumor immune microenvironment and immunotherapy efficacy.

The immune checkpoint regulator PD-L1 expression are associated with clinical progression in prostate cancer

BackgroundThe programmed death 1 (PD-1)/programmed death-ligand 1 (PD-L1) have shown positive efficacy in several solid cancers due to their targeted antitumour effects. However, the frequency and clinical implication value in prostate cancer still remain unclear.MethodsThe PD-1/PD-L1 expression was detected by immunohistochemical (IHC) analysis in 96 retrospectively collected cases of prostatic cancer and 44 controls of benign prostatic hyperplasia (BPH). Its correlation with clinicopathological features including age, PSA level, Gleason score, lymph node metastasis, clinical T stage and risk factor grade in prostate cancer was also assessed.ResultsThe PD-L1-positive expression was significantly higher in cancer cases compared with benign tissues, whereas no difference in PD-1 positive expression was found. Moreover, the PD-L1 expression in tumour cells or lymphocytes was associated with Gleason score, but not related to age, preoperative PSA level, clinical T-stage, lymph node metastasis and grade of risk factors. In addition, no association between the positive expression of PD-1 and PD-L1 in tumour cells and lymphocytes was found.ConclusionsThe expression of PD-L1 not PD-1 is highly prevalent in prostate cancer. PD-L1 is closely related to Gleason score and may be a co-factor associated with the progression of prostate cancer.

α1-Acid Glycoprotein Enhances the Immunosuppressive and Protumor Functions of Tumor-Associated Macrophages

Blood levels of acute-phase protein α1-acid glycoprotein (AGP, orosmucoid) increase in patients with cancer. Although AGP is produced from hepatocytes following stimulation by immune cell-derived cytokines under conditions of inflammation and tumorigenesis, the functions of AGP in tumorigenesis and tumor progression remain unknown. In the present study, we revealed that AGP contributes directly to tumor development by induction of programmed death ligand 1 (PD-L1) expression and IL6 production in macrophages. Stimulation of AGP induced PD-L1 expression in both human monocyte-derived macrophages through STAT1 activation, whereas AGP had no direct effect on PD-L1 expression in tumor cells. AGP also induced IL6 production from macrophages, which stimulated proliferation in tumor cells by IL6R-mediated activation of STAT3. Furthermore, administration of AGP to AGP KO mice phenocopied effects of tumor-associated macrophages (TAM) on tumor progression. AGP decreased IFNγ secretion from T cells and enhanced STAT3 activation in subcutaneous tumor tissues. In addition, AGP regulated PD-L1 expression and IL6 production in macrophages by binding with CD14, a coreceptor for Toll-like receptor 4 (TLR4), and inducing TLR4 signaling. These results provide the first evidence that AGP is directly involved in tumorigenesis by interacting with TAMs and that AGP might be a target molecule for anticancer therapy. SIGNIFICANCE: AGP-mediated suppression of antitumor immunity contributes to tumor progression by inducing PD-L1 expression and IL6 production in TAMs.

Programmed Death Ligand 1 (PD-L1) Expression and its Association with Clinicopathologic Profile in Patients with Non-Small Cell Lung Cancer in a Philippine Tertiary Medical Center

Introduction. The current management of advanced non-small cell lung cancer (NSCLC) includes the characterization of Programmed Death Ligand-1 (PD-L1) expression for potential immune checkpoint inhibitor treatment. There is currently no available data regarding the patterns of PD-L1 expression in NSCLC, as well as their association with clinicopathologic profile in Filipino patients. Methodology. Clinicopathologic characteristics of 187 consecutive NSCLC clinical samples with PD-L1 testing using the clone 22C3 pharmaDx kit were collected. The presence of stromal tumor-infiltrating lymphocytes (TILs) were assessed in hematoxylin and eosin-stained slides. PD-L1 expression on tumor cells (TC) and stromal TILs were evaluated. Results. Of the 187 cases, there were 112 males and 75 females. The mean age at diagnosis was 66.4 years old (32-92 years old). It is composed of 131 cases of Adenocarcinoma, 15 Squamous cell carcinoma, 4 Adenosquamous carcinoma, 32 Non-small cell carcinoma, not otherwise specified, 3 poorly differentiated malignancy, 1 Large cell carcinoma, and 1 Mucinous carcinoma. Specimen types included 17 pleural fluid cell blocks, 60 tumor cell block samples, and 110 tissue biopsies. Tumor cell PD-L1 expression was identified in 59.1% of the 110 tissue biopsies. PD-L1 TPS for histologic specimens are as follows: TPS >50%, TPS 1-49%, and TPS <1% were observed in 23.6%, 35.5%, and 40.9% in our lung cancer cohort, respectively. Of the 77 cytology specimens, 50.6% presented with TC PD-L1 expression. TPS for this subgroup include: 49.4% with no PD-L1 expression, 35.1% with low PD-L1 expression, and 15.6% showing high PD-L1 expression. PD-L1 expression on TC did not correlate with age, sex, or histology for both specimen type subgroups. Stromal tumor-infiltrating lymphocytes were noted in 74.5% of tissue biopsies. Tumor cell block samples did not demonstrate stromal TILs. For tissue biopsies, female gender and TPS 1-49% were more likely to have <50% PD-L1 expression on TILs. Conclusion. Overall TC PD-L1 expression was observed in more than half (55.6%) of NSCLC patients in our cohort. The prognostic value of PD-L1 and clinical response to immune checkpoint inhibitors in the Filipino population needs to be further investigated.

High Expression of Programmed Death-Ligand 1 (PD-L1) Correlates with Macrophage Gene Expression and Is Associated with Prolonged Progression-Free Survival (PFS) in Patients (pts) with First-Line (1L) Diffuse Large B-Cell Lymphoma (DLBCL)

▪Introduction PD-L1 and its receptor PD-1 are both expressed on multiple cell types, including antigen-presenting cells, T cells and tumor cells. In DLBCL, PD-L1 expression on non-malignant immune cells is common, whereas tumor-cell PD-L1 expression is restricted to a small percentage of pts. Because PD-L1/PD-1 are expressed on macrophages after in vitro activation, and activated macrophages contribute to antibody-dependent cellular phagocytosis (ADCP), high PD-L1 expression may identify tumors enriched with activated tumor-infiltrating macrophages primed for ADCP. Considering the role of ADCP in clinical responses to anti-CD20 (rituximab/obinutuzumab), we hypothesized that PD-L1 expression could reflect abundance of activated tumor-infiltrating macrophages and may be associated with prolonged PFS in 1L DLBCL. We leveraged 2 large Phase 3 trials and cell-line immune gene expression to better understand the biological and clinical relevance of PD-L1 expression in 1L DLBCL.Methods We used clinical, genomic and pre-treatment immunohistochemistry (IHC) data from 1L DLBCL pts treated in the MAIN (NCT00486759) and GOYA (NCT01287741) trials. Pre-treatment tissue microarray cores from 201 MAIN pts were stained for PD-L1 (clone SP263), with 21 uninvolved lymph node FFPE sections used as controls. PD-L1+ samples were defined as IHC > 1+ (> 1% tissue area occupied by PD-L1+ cells). Tumor cells were identified based on morphological/cytological features, and PD-L1 tumor expression was scored as a percentage. Activated B-cell (ABC), germinal center B-cell (GCB) and unclassified DLBCL prognostic subtypes were determined by the NanoString Lymph2Cx cell-of-origin (COO) assay. We quantified mRNA expression of PD-L1, macrophage and B-cell genes using TruSeq (Illumina) RNAseq among 702 DLBCL pts (GOYA, n = 552; MAIN, n = 150), with 28 DLBCL cell lines and 15 purified normal B-cell samples as comparators. High/low expression of each gene signature was determined by median cutoffs. Median follow-up durations were 24 and 29 mo in MAIN and GOYA, respectively (≈ 30% of PFS events in both cohorts). We used Cox regression to examine associations between these markers and PFS, adjusting for IPI, age, COO, sex and treatment arm.Results Among 201 DLBCL pts in MAIN, PD-L1 was primarily detected on inter-follicular cells with myeloid/dendritic morphology, similar to the PD-L1 staining pattern of normal lymph nodes. In samples with evaluable germinal centers (GCs), a subset of GC cells expressed PD-L1 with a punctate and granular pattern consistent with a myeloid origin. Overall, there were significantly more pts with high PD-L1 expression by IHC (IHC 3+) and mRNA among ABC vs GCB DLBCL pts. A minority of DLBCL pts (10%) had PD-L1+ tumor cells, consistent with low/undetectable CD274 (PD-L1) mRNA in the majority of DLBCL cell lines and purified normal B-cell samples tested. Additionally, among the 702 evaluable pts in both studies, CD274 mRNA inversely correlated with a B-cell gene signature (MAIN, r= −0.55; GOYA, r= −0.32). High PD-L1 expression (IHC 2+/3+) correlated with prolonged PFS (HR, 0.44 [0.24, 0.80]; P < 0.01) among the 201 evaluable pts in MAIN. Among 552 evaluable pts in GOYA, CD274 expression was higher in pts with a PET-CR (P= 0.02), particularly in pts with ABC DLBCL (P= 0.0001), with a trend toward prolonged PFS in the ABC subtype (HR, 0.80 [0.63, 1.0]; P= 0.054). CD274 mRNA positively correlated with macrophage gene expression in both cohorts (MAIN, r= 0.61; GOYA, r= 0.57); pts with high PD-L1 expression (IHC 2+/3+) also demonstrated high mRNA expression of the macrophage marker CD68. Consistent with PD-L1 reflecting abundance of activated tumor-infiltrating macrophages relevant to anti-CD20 response, high expression of a macrophage signature correlated with prolonged PFS (HR, 0.63 [0.45, 0.87]; P= 0.003) in GOYA and a trend toward prolonged PFS among DLBCL pts treated in MAIN (HR, 0.64 [0.35, 1.16]; P= 0.10), although statistical significance was not reached.Conclusions In 1L DLBCL, most pts expressed PD-L1 on immune cells with myeloid/dendritic morphology, potentially reflecting activated macrophages primed for ADCP and supportive of the correlation between high PD-L1 expression and improved clinical outcomes among pts treated with immunochemotherapy. In the context of anti-CD20, the biology of PD-L1 expression on macrophages and the impact of PD-L1/PD-1 blockade on ADCP merit further study. DisclosuresMcCord:Genentech, Inc.: Employment. Bolen:Genentech: Employment, Equity Ownership. Koeppen:Genentech, Inc.: Employment. Kadel:Genentech, Inc.: Employment. Fingerle-Rowson:F. Hoffmann-La Roche Ltd: Employment, Equity Ownership. Oestergaard:F. Hoffmann-La Roche Ltd: Employment. Venstrom:Genentech, Inc.: Employment.

Immunohistochemical analysis of CD155 expression in triple-negative breast cancer patients.

CD155 is an immune checkpoint protein. Its overexpression is an indicator of poor prognosis in some types of cancer. However, the significance of CD155 expression in patients with triple-negative breast cancer, and the relationship between CD155 and programmed death-ligand 1 (PD-L1) expression, have not yet been analyzed in detail. Using immunohistochemical staining and tissue microarrays, we analyzed the expression profiles of CD155 and PD-L1 in 61 patients with triple-negative breast cancer. Relapse-free survival and overall survival rates were compared according to CD155 expression. The correlation between CD155 expression and clinicopathological factors, including PD-L1 expression (using SP142 and 73-10 assays), was also examined. CD155 expression was noted in 25 patients (41.0%) in this cohort. CD155 expression did not correlate with pathological stage, histological grade, Ki-67 labeling index, or stromal tumor-infiltrating lymphocytes. Only PD-L1 expression in tumor cells by SP142 assay significantly correlated with CD155 expression (p = 0.035); however, PD-L1 expression in tumor cells by 73-10 assay did not show a correlation (p = 0.115). Using the 73-10 assay, 59% of patients showed CD155 and/or PD-L1 expression in tumor cells. Moreover, using the SP142 assay, 63.3% of patients showed CD155 and/or PD-L1 expression in immune cells. CD155 expression did not correlate with either relapse-free survival or overall survival (p = 0.485 and 0.843, respectively). CD155 may be a novel target for antitumor immunotherapy. The results of this study indicate that CD155 may expand the pool of candidates with triple-negative breast cancer who could benefit from antitumor immunotherapy.

Expression of programmed death ligand 1 (PD-L1) in urothelial bladder carcinoma (immunohistochemical and histopathological study)

The aim of this work is to evaluate the immunohistochemical expression of PD-L1 in tumor cells of urothelial bladder carcinoma. PD-L1 immunoexpression was assessed on 20 cases of radical cystectomy specimens using monoclonal rabbit anti- PD-L1 antibody. Extent of membranous PD-L1 expression was assigned in each case. Tumor cells showing > 5% expression were considered positive. PD-L1was seen in 6 (30%) cases [1 case score +2 and 5 cases score +3], while 14(70%) cases were negative [7 cases score 0 and 7 cases score +1]. PD-L1 expression in tumor cells was insignificantly correlated with different available clinicopathological parameters such as sex, pathological stage, associatedbilharzial infestation, necrosis, perineural invasion and associated tumor infiltrating mononuclear cells (TIMCs), although PD-L1 positivity tend to predominate in advanced pathological stage of tumor (T3 and T4). These findings may have clinical implications for the management of patients with PD-L1 positive urothelial bladder carcinoma.