Tumor Programmed Death Ligand 1 Expression Research Articles

Prognostic and Predictive Value of Microsatellite Instability, Inflammatory Reaction and PD-L1 in Gastric Cancer Patients Treated with Either Adjuvant 5-FU/LV or Sequential FOLFIRI Followed by Cisplatin and Docetaxel: A Translational Analysis from the ITACA-S Trial.

Patients with high microsatellite instability (MSI) gastric cancer (GC) show improved survival and no benefit or harm from adjuvant and/or perioperative chemotherapy. The role of immune microenvironment in GC is largely unknown. In the present study, 256 tumor tissue blocks were centrally collected from patients enrolled in ITACA-S, a randomized adjuvant trial of 5-FU/LV versus sequential FOLFIRI and cisplatin-docetaxel. MSI status was assessed by multiplex PCR, inflammatory reaction by H&E morphological assessment, and programmed death-ligand 1 (PD-L1) expression by immunohistochemistry. Overall, 9% patients had MSI-high tumors, 23% had high inflammatory reaction, 11% had tumor PD-L1 ≥ 1%, and 11% had stromal PD-L1 ≥ 1%. A significant association with disease-free survival (DFS) and overall survival (OS) was found for MSI-high (hazard ratio [HR], 0.43; p = .02; HR, 0.40; p = .02) and high inflammatory reaction (HR, 0.55; p = .010; HR, 0.53; p = .008) but not for PD-L1. At multivariable analysis, only MSI showed an independent association with both DFS (p = .02) and OS (p = .01), whereas inflammatory reaction showed an independent association only with OS (p = .04). Patients with tumor PD-L1 ≥ 1% had a significantly longer DFS in sequential chemotherapy than in than 5-FU/LV arm (interaction p = .04) and a trend for OS (interaction p = .12). Our data suggest that MSI status could be a useful prognostic biomarker in patients with radically resected stage II-III GC and should be used as stratification factor in future trials. Tumor PD-L1 ≥ 1% should be further investigated as a potential predictor of benefit from intensive chemotherapy. In this post hoc analysis of patients with radically resected gastric cancer randomized to an intensive sequential chemotherapy regimen versus 5-FU/LV monotherapy as adjuvant treatment in the ITACA-S trial, MSI-high status was independently associated with better disease-free survival and overall survival (OS) and inflammatory reaction was independently associated with better OS. Moreover, tumor PD-L1 expression ≥1% was associated with greater benefit from intensive sequential chemotherapy compared with 5-fluorouracil plus leucovorin (5-FU/LV), whereas PD-L1 expression <1% was not, conditioning a statistically significant interaction between such biomarker and treatment arms. The meta-analysis of individual patients' data from available studies could yield data on the role of MSI status that could inform clinical decisions.

Pembrolizumab with R-CHOP in Previously Untreated Diffuse Large B-Cell Lymphoma: Potential for Biomarker Driven Therapy

Background: Tumor programmed death-ligand 1 (PD-L1) expression in diffuse large B-cell lymphoma (DLBCL) is associated with inferior outcomes. We hypothesized that the first-line immunologically-replete setting may be an opportune time for introducing PD-1 inhibition. We thus evaluated pembrolizumab in combination with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) in untreated patients with DLBCL. Methods: Eligible patients were age 18 or older, had adequate organ function, and had DLBCL or grade 3B FL requiring full-course therapy. Patients received pembrolizumab 200 mg/cycle with R-CHOP for 6 cycles, every 21 days, measuring toxicity as the primary endpoint. Response assessment utilized standard criteria, and PD-L1 staining was performed at a validated central laboratory. Findings: Among 30 treated patients, toxicity was comparable to standard R-CHOP but with two grade ≥3 immune related adverse events (rash, pneumonitis). The overall and complete response rate was 90% and 77%. Only 1 of 4 partial responders has progressed. With 25·5 months of median follow-up, 2-year progression-free survival (PFS) is 83%. PD-L1 tumor expression was associated with non-GCB subtype, and improved PFS and survival.InterpretationPembrolizumab can safely be added to R-CHOP, and is associated with a high CR rate and 2-year PFS. Improved PFS with PR-CHOP in PD-L1 expressing tumors contradicts historical data in R-CHOP treated patients, and supports further trials evaluating PD-L1 as a biomarker to identify DLBCL patients who may benefit from this first-line strategy. Trial Registration: NCT02541565. Funding Statement: In addition to primary funding from Merck Sharpe and Dohme Corp, the authors recognize additional support from grant K24CA184039, NIH/NCI Cancer Center Support Grant P30 CA015704, and donations from Frank and Betty Vandermeer and Sonya and Tom Campion. Declaration of Interests: S.D.S. reports grants and nonfinancial research support from Acerta Pharma BV, Astrazeneca, De Novo Biopharma, Genentech, Jannsen Pharmaceuticals, Incyte Corporation, Merck Sharp and Dohme Corp., Pharmacyclics, Portola Pharmaceuticals, and Seattle Genetics; S.D.S.’ spouse receives research support from Ayala, Bristol Myers Squibb, Merck Sharp Dohme Corp, and Ignyta. S.D.S reports personal fees from Merck Sharp and Dohme Corp and Astrazeneca. A.K.G. reports grants and nonfinancial research support from Teva, Bristol-Myers Squibb, Merck, Takeda, Seattle Genetics, Pfizer, Janssen, Takeda, and Effector; Personal fees and nonfinancial support from Seattle Genetics, Pfizer, Janssen, Gilead, Sanofi, Spectrum, Amgen, Aptevo, BRIM bio, Acerta, I-Mab-pharma, Compliment, Asana Bio, and Incyte. H.R., K.B., J.V., Q.W. report no relevant financial disclosures. M.S. reports grands and nonfinancial research support from Mustang Bio, Celgene, Pharmacyclics, Gilead, Genentech, Abbvie, TG therapeutics, Beigene, Acerta Pharma, Merck Sharp and Dohme Corp; personal fees and nonfinancial support from Abbvie, Genentech, Astra Zeneca, Sound Biologics, Verastem, ADC therapeutics and Atara Biotherapeutics. B.G.T. reports grants and nonfinancial research support from Mustang Bio and RocheGenentech, and patents/royalties from Mustang Bio. R.C.L. reports grants and nonfinancial research support from Incyte Corporation, TG Therapeutics, Takeda, Juno Therapeutics, Rhizen Pharmaceuticals. A.J.C. reports grants and nonfinancial research support from Janssen, AbbVie, Juno Therapeutics, and Celgene; personal fees and nonfinancial support from Celgene. C.U. reports grants and nonfinancial research support from Pharmacyclics, Abbvie, and Celgene; personal fees and nonfinancial support from Amgen, bayer, Pfizer, Gilead, Astrazeneca, Genentech, Pharmacyclics, Abbvie, and Atara. A.R.S. reports grants and nonfinancial research support from Seattle Genetics, Spectrum Pharmaceuticals, and personal fees and nonfinancial support from Kyowa Hakko Kirin. R.D.C reports grants and nonfinancial research support from Merck Sharp and Dohme Corp., Incyte, Seattle Genetics, Vanda Pharmaceuticals, Amgen, Pfizer, Kite/Gilead; and personal fees and nonfinancial support from Amgen, Pfizer, Jazz, and Adaptive Biotechnologies. Ethics Approval Statement: This study was approved by the Fred Hutchinson Cancer Center- University of Washington Consortium IRB and all patients provided written informed consent to participate in the trial.

Prognostic significance of programmed death-1 (PD-1) and programmed death-ligand 1 (PD-L1) expression in uterine carcinosarcoma

ObjectiveThe aim of this study was to evaluate the clinical and prognostic importance of programmed death-1 (PD-1) and/ or programmed death-ligand 1 (PD-L1) in uterine carcinosarcoma (UCS). Study DesignFormalin-fixed, paraffin-embedded tissue samples from 59 cases with UCS were analyzed. PD-1 and PD-L1 expressions in tumor tissue and microenvironment were detected by immunohistochemistry. Clinical and pathological characteristics including age, stage, initial symptom, surgical approach, myometrial invasion, lymphovascular space invasion (LVSI), lymph node invasion, adjuvant therapy, and survival were evaluated. The Kaplan-Meier and Cox proportional hazards models were used to compare the outcomes and prognostic factors. ResultsPD-1 expression in tumor tissue and microenvironment was detected in 15 (25 %) and 18 (30 %) cases, respectively. PD-L1 expression in tumor tissue and microenvironment was detected in 15 (25 %) and 12 cases (20 %), respectively. PD-L1 expression in tumor was associated with longer survival and median survival was 38 and 15 months in cases with and without PD-L1 expressions, respectively (p = 0.019). Lymphovascular space invasion (LVSI) (p = 0.014), myometrial invasion (p = 0.008) and PD-L1 expression were found to be prognostic for UCS’s. PD-L1 expression was found to be an independent good prognostic factor with Cox regression analysis (OR 3.9; 95 % CI: 1.4–11.0) for overall survival. ConclusionPD-1 and/or PD-L1 expression are important due to their expressions in one fourth of the cases with UCS and PD-1/PD-L1 blockade may be a new avenue in UCS.

505P - PD-L1 expression in ALK rearranged NSCLC: All questions answered?

BackgroundTreatment of non-small cell lung cancer (NSCLC) has undergone a paradigm shift in the last decade with the advent of targeted therapy and immunotherapy. Anaplastic Lymphoma Kinase (ALK) rearrangement and Programmed Death-Ligand 1 (PD-L1) expression are important predictive biomarkers for response to targeted therapy and immunotherapy respectively. How these two biomarkers interplay with each other is yet to be determined. Various studies have tried to establish a relationship between PD-L1 expression in tumors and treatment outcomes in ALK rearranged NSCLC, with conflicting results. There is a paucity of data regarding this relationship from the Indian subcontinent. MethodsPD-L1 expression was assessed in tissue samples of 58 patients with advanced ALK rearranged NSCLC treated between 2015 and 2018. PD-L1 expression was measured by immunohistochemistry using VENTANA PD-L1 (SP263) antibody on formalin-fixed paraffin-embedded specimens. The epidemiological profile of patients and the relationship between progression free survival (PFS) on small molecule ALK inhibitor and PD-L1 expression were noted. ResultsThe median age was 47 years (range 25-72 years) and there were 25 males (50%). Most of the patients were never smokers (88%). Thirty-seven (63.7%) of tumors expressed PD-L1 (≥1%) and 13 (22.4%) tumors had a PD-L1 expression of ≥ 50%. All of the patients received crizotinib as first line ALK inhibitor. Of the 44 patients evaluable for treatment response there was no significant difference in PFS between PDL1 negative cohort (median PFS - 13.8 months, CI 6.2-21.3 months) and PDL1 positive cohort (median PFS 10.9 months, CI 6.5-15.2 months, P-0.81). No association was seen between PD-L1 expression and PFS when PD-L1 expression levels were stratified by median or quartiles. In the subgroup analysis, PFS was not significantly different between different patterns of PDL1 expression or intensity of staining. ConclusionsIn contrast to previous studies, we found a higher incidence of PD-L1 expression in patients with ALK rearranged advanced NSCLC. PFS on ALK inhibitors did not differ based on PD-L1 expression. However, this was a retrospective study in a limited number of patients. More prospective studies are needed to confirm our findings. Legal entity responsible for the studyThe authors. FundingHas not received any funding. DisclosureAll authors have declared no conflicts of interest.

HBD3 Induces PD-L1 Expression on Head and Neck Squamous Cell Carcinoma Cell Lines.

Human β-defensin 3 (HBD3) is an antimicrobial peptide up-regulated in the oral tissues of individuals with head and neck squamous cell carcinomas (HNSCC) and oral squamous cell carcinomas (SCC) and present in high concentrations in their saliva. In this study, we determined if HBD3 contributes to HNSCC pathogenesis by inducing programmed death-ligand 1 (PD-L1) expression on HNSCC cell lines. For this, SCC cell lines SCC4, SCC15, SCC19, SCC25, and SCC99 (5.0 × 104 viable cells) were used. Cells were incubated with IFNγ (0.6 µM) and HBD3 (0.2, 2.0, or 20.0 µM) for 24 h. Cells alone served as controls. Cells were then treated with anti-human APC-CD274 (PD-L1) and Live/Dead Fixable Green Dead Cell Stain. Cells treated with an isotype antibody and cells alone served as controls. All cell suspensions were analyzed in a LSR II Violet Flow Cytometer. Cytometric data was analyzed using FlowJo software. Treatment with IFNγ (0.6 µM) increased the number of cells expressing PD-L1 (p < 0.05) with respect to controls. Treatment with HBD3 (20.0 µM) also increased the number of cells expressing PD-L1 (p < 0.05) with respect to controls. However, treatment with IFNγ (0.6 µM) was not significantly different from treatment with HBD3 (20.0 µM) and the numbers of cells expressing PD-L1 were similar (p = 1). Thus, HBD3 increases the number of cells expressing PD-L1. This is a novel concept, but the role HBD3 contributes to HNSCC pathogenesis by inducing PD-L1 expression in tumors will have to be determined.

PD-L1 Expression in De Novo Metastatic Castration-sensitive Prostate Cancer.

De novo metastatic castration-sensitive prostate cancer (mCSPC) is small subgroup of prostate cancer associated with poor prognosis. The aim of our study was to assess the expression of programmed death-ligand 1 (PD-L1) in tumor cells of de novo mCSPC patients. Patients referred to our institution from January 2007 to October 2017 with de novo mCSPC and available diagnostic tissue were included. We tested the PD-L1 pharmaDx qualitative immunohistochemical assay, a monoclonal rabbit anti-PD-L1, clone 28-8 intended for use in the detection of PD-L1 protein in formalin-fixed paraffin-embedded. Kaplan-Meier method was used to estimate survivals according to the expression of PD-L1. The study population included 32 de novo mCSPC patients, analyzed for PD-L1 expression using 2 cut-off values (1% and 5%) to define the positivity. Total of 46.9% of cases had tumor PD-L1 expression ≥1%, and 31.3% had expression ≥5%. No differences were found between the PD-L1 expression ≥1% and the involvement of liver, lung, and number of bone metastases, and the disease volume based on CHAARTED classification. PD-L1 tumors had higher incidence of Gleason score ≥8 compared with PD-L1 tumors (P=0.037), while the incidence of lymph node metastases was higher in PD-L1 tumors (P=0.044). No difference in the median overall survival (mOS) was observed between the PD-L1 population and the PD-L1 patients (43.8 vs. 29.6 mo; P=0.88). The tumor PD-L1 expression cannot be considered a prognostic factor for de novo mCSPC, even if its prognostic and predictive significance have to be thoroughly investigated to better define the selected group of prostate cancer patients that might benefit from checkpoint blockade immunotherapy.

Comparison of tumor cell numbers and 22C3 PD-L1 expression between cryobiopsy and transbronchial biopsy with endobronchial ultrasonography-guide sheath for lung cancer

BackgroundWe previously reported cryobiopsy (Cryo) with endobronchial ultrasonography-guide sheath (EBUS-GS) for peripheral pulmonary lesions (PPLs) provides significantly larger tissues than transbronchial biopsy (TBB) and provides high quantity and quality DNA for gene analysis by next generation sequencing. However, the tumor cell yields and programmed death ligand 1 (PD-L1) expression between each approach have not been compared. Here, we assessed the tumor cell numbers and PD-L1 expression for Cryo with EBUS-GS for PPLs and TBB in patients with lung cancer.MethodsSixteen patients were enrolled in this prospective study from June to November 2017 at Tokyo Women’s Medical University Hospital. The number of tumor cells from a single biopsy, total number of tumor cells, average number of tumor cells, and 22C3 PD-L1 expression (≥ 50% and ≥ 1%) were compared between Cryo and TBB.ResultsThe numbers of tumor cells from a single biopsy, total numbers of tumor cells, and average numbers of tumor cells obtained by Cryo were significantly larger than those obtained by TBB (Cryo [means ± standard errors of the means]: 1321 ± 303.7, 1981 ± 411.7, and 1406 ± 310.3; TBB: 208.8 ± 38.24, 1044 ± 189.0, and 208.8 ± 37.81; P < 0.0001, P = 0.0474, P = 0.0006, respectively). PD-L1 ≥ 50% and ≥ 1% patients for Cryo were 18.8 and 56.3%, respectively, whereas those for TBB were 12.5 and 37.5%, respectively. The sensitivity, specificity, positive predictive value, negative predictive value, concordance, and κ coefficient based on Cryo for TBB were 66.7, 100, 100, 92.9, 93.8%, and 0.7647, respectively, for PD-L1 ≥ 50%; and 44.4, 71.4, 66.7, 50, 56.3%, and 0.1515, respectively, for PD-L1 ≥ 1%.ConclusionCryo with EBUS-GS may be a useful diagnostic approach for lung cancer, with advantages over TBB for gene analysis and whole exon sequencing. Particularly, it could contribute to patients taking pembrolizumab as first-line therapy when PD-L1 was negative by evaluating TBB specimens. It could also provide ample tissue for PD-L1 expression analysis in addition to accurate diagnosis and gene analysis.

Circulating Tumor Cell PD-L1 Expression as Biomarker for Therapeutic Efficacy of Immune Checkpoint Inhibition in NSCLC.

Over the last decade, the immune checkpoint blockade targeting the programmed death protein 1 (PD-1)/programmed death ligand 1 (PD-L1) axis has improved progression-free and overall survival of advanced non-small cell lung cancer (NSCLC) patients. PD-L1 tumor expression, along with tumor mutational burden, is currently being explored as a predictive biomarker for responses to immune checkpoint inhibitors (ICIs). However, lung cancer patients may have insufficient tumor tissue samples and the high bleeding risk often prevents additional biopsies and, as a consequence, immunohistological evaluation of PD-L1 expression. In addition, PD-L1 shows a dynamic expression profile and can be influenced by intratumoral heterogeneity as well as the immune cell infiltrate in the tumor and its microenvironment, influencing the response rate to PD-1/PD-L1 axis ICIs. Therefore, to identify subgroups of patients with advanced NSCLC that will most likely benefit from ICI therapies, molecular characterization of PD-L1 expression in circulating tumor cells (CTCs) might be supportive. In this review, we highlight the use of CTCs as a complementary diagnostic tool for PD-L1 expression analysis in advanced NSCLC patients. In addition, we examine technical issues of PD-L1 measurement in tissue as well as in CTCs.

Retrospective analysis of docetaxel in combination with ramucirumab for previously treated non-small cell lung cancer patients.

Current clinical trials demonstrated that combination regimens comprising chemotherapy and immunotherapy lead to better patient outcomes compared to chemotherapy alone as the first line of treatment for non-small cell lung cancer (NSCLC). In addition, the combination therapy of docetaxel (Doc) and ramucirumab (Ram) was considered one of the standard treatments for advanced or relapsed NSCLC patients. However, little is known about the therapeutic responders of this combination therapy among previously treated NSCLC patients. In the present study, we aimed to identify predictive factors for therapeutic response, including programmed death-ligand 1 (PD-L1) expression in tumors, for Doc treatment in combination with Ram. We retrospectively analyzed a total of 135 advanced or relapsed NSCLC patients who were refractory to platinum-based chemotherapy at eleven institutions in Japan between July 2016 and November 2018. Our observations showed that PD-L1 expression in tumors is not associated with the efficacy of combined therapy of Doc and Ram in previously treated NSCLC patients. Analysis of the patient clinical profiles indicated that prior treatment with immune checkpoint inhibitors (ICIs) is a reliable predictor for the good progression-free survival (PFS) to this combination therapy (P=0.041). Our retrospective study indicated that combination regimens comprising chemotherapy and ICIs followed by Doc and Ram could be an optimal therapeutic option for NSCLC patients regardless of the PD-L1 status of tumors. Further investigations are required to strengthen clinical evidence demonstrating the effectiveness of the combination therapy of Doc plus Ram in previously treated NSCLC patients.

Primary tumor resection for initially staged IV breast cancer: An emphasis on programmed death-ligand 1 expression, promoter methylation status, and survival.

Conventional therapy modalities for advanced breast cancer are problematic, whereas checkpoint blockade immunotherapy has been considered as a promising approach. This study aims to determine programmed death-ligand 1 (PD-L1) expression and methylation status of PD-L1 promoter in primary tumor tissue and metastatic foci of patients with stage IV breast cancer.Clinicopathological data and survival rates of 57 breast cancer patients, who were initially staged IV, and operated for intact tumors, were retrospectively analyzed. Immunohistochemical analysis of PD-L1 using 57 primary tumors, 33 paired metastatic lymph nodes, and 14 paired distant metastases was performed. Additionally, the methylation rate of the PD-L1 gene promoter region was determined with real-time polymerase chain reaction (PCR) analysis in 38 samples.Overall PD-L1 expression in primary tumors was 23.1% (12/52). PD-L1 positivity was reduced in lymph nodes by 15.2% (5/33) and in distant metastases by 21.4% (3/14). PD-L1 expression diverged between primary and metastatic foci in a subset of cases (18.2% for lymph node and 33.3% for distant metastasis). In general, the PD-L1 promoter was not methylated, and mean methylation rates were low (min. 0%–max. 21%). We observed no correlation between PD-L1 expression, promoter methylation, and survival.Neither the expression nor the methylation status of PD-L1 in patients, who were presented with stage IV breast cancer and operated for an intact primary tumor, had a statistically significant relation with survival. Discordance in PD-L1 expression between primary tumor and metastasis should be considered during pathological and clinical management of patients who would undergo checkpoint blockade therapy.

PD-1 and PD-L1 expression in pulmonary carcinoid tumors and their association to tumor spread.

Pulmonary carcinoid (PC) tumors are rare tumors that account for approximately 1% of all lung cancers. The primary treatment option is surgery, while there is no standard treatment for metastatic disease. As the number of PCs diagnosed yearly is increasing, there is a need to establish novel therapeutic options. This study aimed to investigate programmed death protein 1 (PD-1) and programmed death ligand 1 (PD-L1) expression in PC tumors since blocking of the PD-1/PD-L1 pathway is a promising therapeutic option in various other malignancies. A total of 168 PC patients treated between 1990 and 2013 were collected from the Finnish biobanks. After re-evaluation of the tumors, 131 (78%) were classified as typical carcinoid (TC) and 37 (22%) as atypical carcinoid (AC) tumors. Primary tumor samples were immunohistochemically labeled for PD-1, PD-L1 and CD8. High PD-1 expression was detected in 16% of the tumors. PD-L1 expression was detected in 7% of TC tumors; all AC tumors were PD-L1 negative. PD-L1 expression was associated with mediastinal lymph-node metastasis at the time of diagnosis (P = 0.021) as well as overall metastatic potential of the tumor (P = 0.010). Neither PD-1 expression, PD-L1 expression nor CD8+ T cell density was associated with survival. In conclusion, PD-1 and PD-L1 were expressed in a small proportion of PC tumors and PD-L1 expression was associated with metastatic disease. Targeting of the PD-1/PD-L1 pathway with immune checkpoint inhibitors may thus offer a treatment option for a subset of PC patients.

Abstract 3224: Copper homeostasis: A new player in anti-tumor immune response

Abstract Immunotherapy has shown great potential for treating aggressive cancers and it is becoming the fourth and newest pillar of cancer therapy complementing surgery, cytotoxic therapy, and radiotherapy. In particular, immune checkpoint inhibitors targeting the PD-1/PD-L1 axis have shown extraordinary clinical efficacy in several types of cancer. This is because tumor cells express molecules, such as the Programmed Death Ligand 1 (PD-L1), to prevent immune cells activity (immune-evasion). The immune checkpoint protein Programmed Death receptor 1 (PD-1) expressed by lymphocytes instructs T-cells not to attack any tumor cell expressing PD-L1. Several therapies anti PD-1/PD-L1 have been approved by FDA, but concerns have been raised about their long term efficacy and safety. Therefore, there is a need for better understanding of the biology and the mechanisms regulating PD-1/PD-L1 axis, to develop different approaches to target this pathway. Drugs modulating the transcriptional and post-transcriptional regulation of PD-L1 could represent new therapeutic strategies for increasing the efficacy and reducing side effects of the current anti PD-L1 antibodies. Copper transporter 1 (CTR-1) and copper levels are elevated in tumors and the use of copper targeting agents is currently under intense investigations. It has been also reported that copper plays a major role in the immune-system, but its activity is unclear. In this study we demonstrated that copper plays a key role in the expression of PD-L1 in cancer cells. Tissue microarrays from neuroblastoma (NB) and glioblastoma patients showed a significant correlation between CTR-1 and PD-L1 expression (p=0.00014 and p=0.012 respectively). In vitro experiments showed that downregulation of CTR-1 caused a decrease of intracellular copper which in turn led to a downregulation of PD-L1 expression in cancer cells. On the other hand, addition of copper into the media clearly induced PD-L1 upregulation. RNA-seq analysis revealed specific pathways and candidate genes associated with tumor copper homeostasis and PD-L1 expression. Consistently, Dextran-Catechin (DC) and TEPA, drugs reducing copper, were able to downregulate PD-L1 expression in tumors. In vivo studies showed that copper lowering drugs prolonged mice survival, and ex vivo immunohistochemistry staining confirmed the downregulation of CTR1 and PD-L1 expression. In addition, 24h and 48h of DC treatments showed an increase of tumor-infiltrating CD4+ and CD8+ lymphocytes and activated Natural Killer cells (NK) cells in NB immune-competent mouse model. In conclusion, there is a strong association between PD-L1 expression and intracellular copper levels. Copper dysregulating agents reduce PD-L1 in vitro and in vivo, highlighting the possibility to enhance tumor immune surveillance by targeting intracellular copper levels. This study shows the potential utility of copper targeting drugs to improve anti-cancer immunotherapies. Citation Format: Florida Voli, Luigi Lerra, Kathleen Kimpton, Federica Saletta, Sylvie Shen, Giuseppe Cirillo, Maria Kavallaris, Orazio Vittorio. Copper homeostasis: A new player in anti-tumor immune response [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3224.

Abstract 3149: Prognostic impact of PD-L1 expression in correlation with neutrophil-to-lymphocyte ratio in squamous cell carcinoma of the lung

Abstract Aim: To investigate the prognostic impact of programmed death-ligand 1 (PD-L1) expression on tumor cells in correlation with neutrophil-to-lymphocyte ratio (NLR) in early-stage squamous cell carcinoma of the lung, as PD-L1 is a potent regulator of cancer immunity and NLR is a potential surrogate of immune status. Patients and methods: Eighty-three patients with completely resected pathologic stage I lung squamous cell carcinoma were retrospectively reviewed. Tumoral PD-L1 expression was evaluated with immunohistochemistry, and its prognostic impact was analyzed in correlation with NLR. Results: Forty-three patients (51.8%) had tumor with positive PD-L1 expression (percentage of tumor cells expressing PD-L1, ≥1%). There was no significant correlation between PD-L1 expression and NLR. PD-L1-positivity failed to provide a significant prognostic impact (overall survival [OS] rate at 5 years, 70.1% in PD-L1-negative patients versus 53.0% in PD-L1-positive patients; P=0.117). Among NLR-low (&amp;lt;2.2) patients, however, PD-L1-positivity was significantly correlated with a poor prognosis (OS rate at 5 years, 86.0% in PD-L1-negative patients versus 46.1% in PD-L1-positive patients; P=0.020). In contrast, among NLR-high (≥2.2) patients, PD-L1-positivity provided no prognostic impact (P=0.680). When NLR status and tumoral PD-L1 status were combined, “NLR-low and tumoral PD-L1-negative” was a significant and independent factor to predict a favorable recurrence-free survival (hazard ratio, 0.237 [95% confidence interval, 0.083 to 0.674]; P=0.007) and OS (hazard ratio, 0.260 [95% confidence interval, 0.091 to 0.745]; P=0.012). Conclusions: The prognostic impact of PD-L1 expression on tumor cells was distinct according to NLR. “NLR-low and tumoral PD-L1-negative” patients showed a favorable prognosis. Citation Format: Kazue Yoneda, Taiji Kuwata, Masataka Mori, Masatoshi Kanayama, Ayako Hirai, Yuko Tashima, Naoko Imanishi, Koji Kuroda, Yoshinobu Ichiki, Fumihiro Tanaka. Prognostic impact of PD-L1 expression in correlation with neutrophil-to-lymphocyte ratio in squamous cell carcinoma of the lung [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3149.

Real-world prevalence of programmed death ligand 1 expression in locally advanced or metastatic non–small-cell lung cancer: The global, multicenter EXPRESS study

Objectives: Tumor programmed death ligand 1 (PD-L1) expression is associated with improved clinical benefit from immunotherapies targeting the PD-1 pathway. We conducted a global, multicenter, retrospective observational study to determine real-world prevalence of tumor PD-L1 expression in patients with NSCLC. Materials and methods: Patients ≥18 years with histologically confirmed stage IIIB/IV NSCLC and a tumor tissue block (≤5 years old) obtained before treatment were identified in 45 centers across 18 countries. Tumor samples from eligible patients were selected consecutively, when possible. PD-L1 expression was evaluated at each center using the PD-L1 IHC 22C3 pharmDx kit (Agilent, Santa Clara, CA, USA). Results: Of 2617 patients who met inclusion criteria, 2368 (90%) had PD-L1 data; 530 (22%) patients had PD-L1 TPS ≥ 50%, 1232 (52%) had PD-L1 TPS ≥ 1%, and 1136 (48%) had PD-L1 TPS < 1%. The most common reason for not having PD-L1 data (n = 249) was insufficient tumor cells (<100) on the slide (n = 170 [6%]). Percentages of patients with PD-L1 TPS ≥ 50% and TPS ≥ 1%, respectively were: 22%/52% in Europe; 22%/53% in Asia Pacific; 21%/47% in the Americas, and 24%/55% in other countries. Prevalence of EGFR mutations (19%) and ALK alterations (3%) was consistent with prior reports from metastatic NSCLC studies. Among 1064 patients negative for both EGFR mutation and ALK alteration, the percentage with PD-L1 TPS ≥ 50% and TPS ≥ 1%, respectively, were 27% and 53%. Conclusions: This is the largest real-world study in advanced NSCLC to date evaluating PD-L1 tumor expression using the 22C3 pharmDx kit. Testing failure rate was low with local evaluation of PD-L1 TPS across a large number of centers. Prevalence of PD-L1 TPS ≥ 50% and TPS ≥ 1% among patients with stage IIIB/IV NSCLC was similar across geographic regions and broadly consistent with central testing results from clinical trial screening populations.

Programmed death ligand 1 (PD-L1) expression in parathyroid tumors.

IntroductionPD-L1 is associated with prognosis and immunotherapeutic response in patients with malignancies. In previous studies, PD-L1 expression was detected in many endocrine tumors. However, the PD-L1 expression status in parathyroid tumors is unknown.MethodsWe included 26 parathyroid carcinoma and 37 adenoma samples, as well as the corresponding patient information. PD-L1 was stained using the FDA-approved PD-L1 IHC 22C3 pharmDx and Ventana PD-L1 (SP263) assays, and staining was assessed by the estimated percentages of positive tumor cells and immune cells, respectively.ResultsWe classified the PD-L1 expression in the parathyroid tumors into four groups: (0) <1%, (1) 1–4%, (2) 5–9% and (3) ≥10% positive. With the SP263 clone, 37 (carcinoma:adenoma = 18:19) samples scored 0, 13 (carcinoma:adenoma = 4:9) scored 1, 7 (carcinoma:adenoma = 1:6) scored 2 and 6 (carcinoma:adenoma = 3:3) scored 3. However, in the series of cases using the 22C3 clone, 45 (carcinoma:adenoma = 20:25) samples scored 0, 10 (carcinoma: adenoma = 3:7) scored 1, 5 (carcinoma:adenoma = 1:4) scored 2, and 3 (carcinoma:adenoma = 2:1) scored 3. Concerning tumor-infiltrating immune cells, 57 samples were negative and six were positive with SP263, and 59 were negative and four were positive with 22C3. Moreover, PD-L1 expression was negatively correlated with the Ki-67 index and mitotic rate in parathyroid tumors depending on the different clones. However, the results indicated only moderate consistency between the SP263 and 22C3 clones in parathyroid tumors.ConclusionWe found deficient PD-L1 expression in the majority of parathyroid tumors. However, the PD-L1 expression score in parathyroid tumors depended greatly on the antibody clone used.

Prognostic Significance of Programmed Death Ligand 1 Expression and Tumor-Infiltrating Lymphocytes in Axial Osteosarcoma

To characterize the intratumoral immune microenvironment and evaluate its clinical implications in patients with primary axial osteosarcoma. Immunohistochemistry was used to interpret tumor programmed death ligand 1 (PD-L1) expression and tumor-infiltrating lymphocytes (TILs) profile of cluster of differentiation 8 (CD8), PD-L1, and programmed death 1 (PD-1) within 69 tumor specimens. Overall, all tumor specimens presented lymphocytic infiltrates, with PD-L1+ TILs being the most common subset (mean, 215.1 per slide mm2). Positive tumor PD-L1 expression was presented in 43.5% of tumors. Moderate to strong relationships were detected among TILs subsets and tumor PD-L1 expression. In addition, the density of PD-L1+ TILs was significantly correlated with favorable clinicopathologic features, including earlier Enneking stage. The positivity of tumor PD-L1 expression was associated with the tumor site and pathologic grade (P= 0.021 and 0.037, respectively). In univariate survival analysis, the high density of PD-L1+ TILs or CD8+ TILs was significantly correlated with both prolonged event-free survival and overall survival (OS), whereas the high infiltration of PD-1+ TILs was significantly associated with reduced OS, as was the positive tumor PD-L1 expression. Furthermore, multivariate analysis showed that CD8+ TILs and PD-L1+ TILs remained their significance for both event-free survival (P= 0.012 and 0.004, respectively) and OS (P= 0.033 and 0.002, respectively). However, both PD-1+ TILs and tumor PD-L1 expression failed to reach significance for OS. Our results suggested that the immune microenvironment is of clinically relevant significance in patients with axial osteosarcoma. Specifically, we identified both PD-L1+ TILs and CD8+ TILs as independent favorable prognostic markers.

Frequency of discordance in programmed death ligand 1 (PD-L1) expression between primary tumors and paired distant metastases in advanced cancers: A systematic review and meta-analysis.

e14290 Background: Randomized trials have demonstrated that PD-L1 expression in tumor cells predicts for response to PD-1 or PD-L1 checkpoint inhibitors in advanced cancers. However, the frequency of discordance in PD-L1 expression between primary tumors and paired distant metastases is currently unclear. We aimed to determine the discordance rate of PD-L1 expression between primary tumor and paired distant metastases in advanced cancers. Methods: We searched MEDLINE and EMBASE for eligible studies. We noted the discordance rate (positive-to-negative or vice versa) and performed subgroup analyses based on the PD-L1 expression in primary tumor, locations of primary tumor and distant metastases, positivity thresholds and type of antibody used for testing. We used QUADAS-2 tool to assess the methodologic quality of the included studies. We performed the meta-analysis using the logistic-normal random effects model. Results: We identified 11 eligible studies including 351 cases of lung, colorectal, breast and ovarian cancers. Nine studies were judged to have low risk of bias in their methodological quality. The overall discordance rate in PD-L1 expression between primary tumor and paired distant metastases was 28% (95% confidence interval (CI) = 18-41) with significant heterogeneity among the studies (chi-square test P-value &lt; 0.0001). There was no statistically significant differences in discordance rates between the subgroups: PD-L1-positive (40%, 95% CI = 21-63) vs PD-L1-negative primary tumors (21%, 95% CI = 12-34), lung primary (31%, 95% CI = 14-55) vs colorectal/ breast/ ovarian primary (27%, 95% CI = 19-37), central nervous system metastases (22%, 95% CI = 8-47) vs liver/ lung/ pleural/ peritoneum metastases (34%, 95% CI = 24-46); 1% (23%, 95% CI 16-33) vs 5% positivity threshold (33%, 95% CI 11-68); E1L3N (42%, 95% CI 10-82) vs SP142 antibody (27%, 95% CI 20-36). Conclusions: The discordance in PD-L1 expression between primary tumors and paired distant metastases is close to 30%, which could potentially affect response to immunotherapy. Further works exploring the mechanisms and impact of this discordance are warranted.

Mutational landscapes and PD-L1 expression in non-small cell lung cancer.

8541 Background: Programmed death-ligand 1 (PD-L1) serves as a major predictive biomarker for immune checkpoint inhibitors in non-small cell lung cancer (NSCLC). However, the relationship between PD-L1 expression and genetic features of NSCLC remains unclear. The aim of this study was to explore the correlation between genetic profiles and PD-L1 expression in NSCLC. Methods: FFPE tumor and matched blood samples from 568 NSCLC (487 adenocarcinomas (ACAs) and 81 squamous carcinomas (SCAs)) patients were collected for NGS-based targeted panel sequencing. Genomic alterations including single nucleotide variations, short and long insertions/deletions, copy number variations and gene rearrangements were assessed. Tumoral PD-L1 expression was evaluated by immunohistochemical analysis (Dako 22C3 and 28-8). Results: The prevalence of PD-L1 expression was 9.9% with a ≥50% cutoff and 27.5% with a ≥1% cutoff. High PD-L1 expression (using a ≥1% cutoff) in tumor cells was significantly associated with mutations of MET (p &lt; 0.001), RET (p = 0.036), ROS1 (p &lt; 0.001), TP53 (p = 0.0013) and 11q13 amplification (p = 0.004), and was inversely correlated with EGFR mutations (p = 0.011). SOX2 and KLHL6 mutations were more frequent in SCAs (33.3% and 28.4%, respectively) than in ACAs (0.4% and 1%, respectively) and were adversely associated with PD-L1 expression in SCAs (p = 0.01, p = 0.004). Gene set 1 (GS1) mutations included EGFR, ALK, KRAS, BRAF, MET, RET, ROS1 and ERBB2 and gene set 2 (GS2) mutations included TP53, RB1, PTEN, APC and MYC. According to the mutation status of GS1 and GS2, 18 patients were classified as type I (GS1-, GS2-), 92 as type II (GS1-, GS2+), 202 as type III (GS1+, GS2-) and 256 as type IV (GS1+, GS2+). PD-L1 expression was higher in Type IV tumors than in type III (33.2% vs. 14.4%, respectively, p &lt; 0.001). Conclusions: We highlighted the genomic heterogeneity of NSCLC according to the mutation status of different gene sets. Our results indicate that patients with GS1 and GS2 gene mutations might correlate with higher PD-L1 expression. Our results help to understand the relationship between genomic features and PD-L1 expression and may be a potential guide for immunotherapy.

Efficacy and a novel clinicopathologic-genomic nomogram of atezolizumab in advanced non-small cell lung cancer (POPLAR and OAK): A combined analysis of two multicenter, randomized, phase II/III trials.

2573 Background: Atezolizumab, a programmed death ligand 1 (PD-L1) inhibitor, prolonged overall survival (OS) compared with docetaxel among patients with previously treated advanced non–small-cell lung cancer (NSCLC) in two independent multicentre, randomized trials (POPLAR and OAK). We conducted a combined analysis of the two trials to evaluate its efficacy and genomic biomarkers, and to further developed a novel predictive clinicopathologic-genomic nomogram of immunotherapy in NSCLC. Methods: Patients (N = 1,137) with stage IIIB/IV NSCLC and disease progression after previously platinum-based chemotherapy were randomly assigned (1:1) to receive atezolizumab (1200 mg/kg every 3 weeks) or docetaxel (75 mg/m2 every 3 weeks). The primary endpoint was OS. We applied a two-stage meta-analysis of pooled individual patient data in the intention-to-treat population. In OAK trial, patients treated with atezolizumab were randomly assigned (1:1) to the training group or the validation group to develop a predictive clinicopathologic-genomic nomogram of immunotherapy. POPLAR and OAK were registered with ClinicalTrials.gov, numbers NCT02008227 and NCT01903993. Results: In the pooled analysis, the median overall survival was 13.49 months (95% confidence interval [CI], 11.95 to 15.22) with atezolizumab versus 9.66 months (95% CI, 8.73 to 10.70) with docetaxel. The risk of death was 28% lower with atezolizumab than with docetaxel (hazard ratio [HR], 0.72; 95% CI, 0.62 to 0.83; P &lt; 0.001). The race, sex, tumor histology, eastern cooperative oncology group performance status, PD-L1 expression, and especially pretreatment mutation (TP53, DNMT3A and KEAP1) were significantly associated with OS, and were used for the development of the predictive nomogram. The clinical use of the nomogram showed a closer association with 3-year OS than the blood-based tumor mutational burden (bTMB) or PD-L1 expression alone (nomogram, AUC = 0.818; bTMB, AUC = 0.701; PD-L1, AUC = 0.526) among NSCLC patients who had received atezolizumab. The superior predictability of the nomogram was further confirmed in the validation and entire OAK cohorts. Conclusions: Among patients with advanced, previously treated NSCLC, OS was significantly better with atezolizumab than with docetaxel. Furthermore, we constructed a novel and powerful clinicopathologic-genomic nomogram for personalized immunotherapy options.

Shorter Survival in Malignant Pleural Mesothelioma Patients With High PD-L1 Expression Associated With Sarcomatoid or Biphasic Histology Subtype: A Series of 214 Cases From the Bio-MAPS Cohort

BackgroundAnticancer immune responses are negatively regulated by programmed cell death 1 (PD-1) T-cell membrane protein interaction with its ligand, programmed death ligand 1 (PD-L1), on cancer cells. We sought to assess the prognostic role of PD-L1 expression in tumor samples from patients enrolled onto the IFCT-0701 MAPS randomized phase 3 trial (NCT00651456). Patients and MethodsTumor samples were analyzed by immunohistochemistry for percentages of PD-L1 membrane-stained tumor cells using the E1L3N clone, and data were correlated to survival by multivariate Cox models including stratification variables. ResultsPD-L1 staining was assessed in 214 (47.75%) of 448 patients. Epithelioid subtype represented 83.7% (179/214). Absence of PD-L1 staining occurred in 137 (64.1%) of 214 malignant pleural mesothelioma (MPM) samples, while 77 (35.9%) of 214 were PD-L1 positive, with 50 (64.9%) of 77 showing < 50% PD-L1–expressing tumor cells. Sarcomatoid/biphasic subtypes were more commonly PD-L1 positive than epithelioid subtype (P < .001). In patients with 1% or more PD-L1–stained tumor cells, median overall survival (OS) was 12.3 months versus 22.2 months for other patients (hazard ratio [HR] = 1.25; 95% confidence interval [CI], 0.93-1.67; P = .14). OS did not differ according to PD-L1 positivity in multivariate analyses (adjusted HR = 1.10; 95% CI, 0.81-1.49; P = .55). With a 50% cutoff, PD-L1–positive patients displayed a 10.5 months median OS versus 19.3 months for patients with lower PD-L1 expression (HR = 1.93; 95% CI, 1.27-2.93; P = .002). OS did not significantly differ in adjusted Cox models (adjusted HR = 1.20; 95% CI, 0.74-1.94; P = .47). In the 179 epithelioid MPM patients, high PD-L1 staining (≥ 50% of tumor cells) negatively affected OS, although not significantly, showing a 12.3-month median OS (95% CI, 4.3-21.6) versus 23-month (95% CI, 18.5-25.2) for patients with tumor PD-L1 staining in < 50% cells (P = .071). The progression-free survival (PFS) differences were statistically significant, with a longer 9.9-month median PFS in patients with low PD-L1 staining (< 50% cells) compared to 6.7 months of median PFS in patients with high PD-L1 expression (≥ 50% cells) (P = .0047). ConclusionAlthough high PD-L1 tumor cell expression was associated with poorer OS in MPM patients from the MAPS trial, its prognostic influence was lost in multivariate analyses in the whole cohort, while PD-L1 expression was strongly associated with the sarcomatoid/biphasic subtypes. In the epithelioid MPM subset of patients, high PD-L1 tumor expression (≥ 50%) negatively affected OS and PFS, with this prognostic influence remaining statistically significant for PFS after adjustment in multivariate Cox model.