Programmed Death Ligand-1 Inhibitors Research Articles

HLA-B27 association of autoimmune encephalitis induced by PD-L1 inhibitor.

ObjectiveWhile immune checkpoint inhibitors are increasingly used for various cancers, unpredictable immune‐related adverse events (irAEs) such as autoimmune encephalitis is life‐threatening. Here, we report an association between human leukocyte antigen (HLA) and atezolizumab‐induced encephalitis.MethodsFrom an institutional prospective cohort for encephalitis, we identified patients with autoimmune encephalitis after the use of atezolizumab, a PD‐L1 (programmed death‐ligand 1) inhibitor, from August 2016 to September 2019 and analyzed their HLA genotypes.ResultsA total of 290 patients received atezolizumab, and seven patients developed autoimmune encephalitis, and five of whom were enrolled for the analysis. The patients presented altered mentality, seizures, or myelitis. Three patients had the HLA‐B*27:05 genotype in common (60%), which is significantly frequent given its low frequency in the general population (2.5%). After Bonferroni correction, HLA‐B*27:05 was significantly associated with autoimmune encephalitis by atezolizumab (corrected P < 0.001, odds ratio 59, 95% CI = 9.0 ~ 386.9).InterpretationHere we found that three in five patients with autoimmune encephalitis associated with atezolizumab had the rare HLA‐B*27:05 genotype. Further systematic analyses in larger cohorts are necessary to investigate the value of HLA screening to prevent the life‐threatening adverse events.

Novel, non-invasive imaging approach to identify patients with advanced non-small cell lung cancer at risk of hyperprogressive disease with immune checkpoint blockade

PurposeHyperprogression is an atypical response pattern to immune checkpoint inhibition that has been described within non-small cell lung cancer (NSCLC). The paradoxical acceleration of tumor growth after immunotherapy has been...

MUC1-induced immunosuppression in colon cancer can be reversed by blocking the PD1/PDL1 signaling pathway.

Mucin1 (MUC1) upregulation in colon cancer has been linked to poor patient outcomes and advanced stage at diagnosis. This is partially due to MUC1-mediated inhibition of T-cell proliferation affecting efficient lysis by cytotoxic lymphocytes, which contributes to escape from immune surveillance. In the present study, human colorectal cancer tissues were collected, and MUC1-positive and MUC1-negative colon cancer mouse models were prepared; subsequently, the number and function of immune cells in tumor tissues were measured using flow cytometry. The present study revealed that MUC1, as a tumor-associated antigen, can recruit more tumor-infiltrating lymphocytes into the tumor microenvironment compared with MUC1-negative colon cancer, but that these cells could not serve antitumor roles. Conversely, the present study demonstrated that MUC1-positive colon cancer attracted more regulatory T cells (Treg cells), myeloid-derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs) to the tumor site than MUC1-negative colon cancer. Furthermore, the data suggested that programmed death protein 1 (PD1)-programmed death ligand 1 (PDL1) expression is greater in MUC1-positive colon cancer. Blocking the PD1-PDL1 signaling pathway reduced the percentage of Treg cells, MDSCs and TAMs in the tumor microenvironment, enhanced T-cell cytotoxicity and inhibited tumor growth, prolonging the survival time of MUC1-positive tumor-bearing mice. Therefore, the present study elucidated the role of MUC1 in tumor immune escape and provides a foundation for the application of PDL1 inhibitors to MUC1-positive colon cancer.

Immunotherapy for extensive stage small cell lung cancer.

Small cell lung cancer (SCLC) is an aggressive malignancy. Until recently the standard of care for newly diagnosed patients with extensive-stage disease was chemotherapy consisting of etoposide plus a platinum (EP). The median overall survival (OS) was only about 10 months with this systemic therapy. Immune checkpoint inhibitors were first evaluated as second or subsequent line treatments in extensive stage disease and later in combination with EP in the first-line setting. Recently two randomized phase III trials have demonstrated statistically improved OS with addition of a programmed death ligand-1 (PD-L1) inhibitor to EP. As a result, the standard of care for newly diagnosed patients with extensive-stage SCLC has changed for the first time in decades. However, many patients do not derive benefit from the addition of a PD-L1 inhibitor to EP. In this review we discuss first-line trials of chemoimmunotherapy in extensive stage SCLC and summarize data on second and subsequent line treatment with immune checkpoint inhibitors in immunotherapy-naïve patients. Additionally, we discuss potential biomarkers that could be utilized to select for which patients derive benefit from addition of a PD-L1 inhibitor to EP and propose ways to improve on first-line chemoimmunotherapy.

Efficacy of neoadjuvant atezolizumab treatment in patients with advanced urothelial bladder cancer according to the BASQ classification: a study protocol for an open-label, two-cohort, phase II trial

IntroductionAtezolizumab is a programmed death ligand-1 inhibitor for urothelial bladder cancer treatment. Atezolizumab has become the standard therapy for patients with urothelial bladder cancer who are not responding to cisplatin-based...

Clinical Outcomes for PD-1 Inhibitor Plus Chemotherapy as Second-Line or Later Therapy Compared to PD-1/PD-L1 Inhibitor Alone in Advanced Non-small-cell Lung Cancer.

BackgroundProgrammed death-1 (PD-1)/programmed death-ligand 1 (PD-L1) inhibitor monotherapy has been approved as second-line or later therapy in advanced non-small-cell lung cancer (NSCLC). The study aimed to compare the clinical outcomes of PD-1 inhibitor plus chemotherapy with PD-1/PD-L1 inhibitor monotherapy as second-line or later therapy in advanced NSCLC.MethodsThe clinical data of patients with advanced NSCLC who received PD-1/PD-L1 inhibitors as second-line or later line therapy was retrospectively collected. Patients were assigned to one of the two groups according to the therapeutic modality used: PD-1/PD-L1 inhibitor monotherapy group or PD-1 inhibitor plus chemotherapy combination therapy group. Disease control rate (DCR), progression-free survival (PFS), and overall survival (OS) were evaluated between the two groups. The prognostic effect of the derived neutrophil-to-lymphocyte ratio (dNLR) and lactate dehydrogenase (LDH) on the outcomes was also evaluated.ResultsFrom April 2017 to October 2019, a total of 84 patients were enrolled in the current study. Twenty-six patients (PD-1 inhibitor, n = 25; PD-L1 inhibitor, n = 1) received PD-1/PD-L1 inhibitor monotherapy, and fifty-eight patients received PD-1 inhibitor plus chemotherapy. The chemotherapy regimens used were as follows: liposome paclitaxel (n = 15); nab-paclitaxel (n = 12); docetaxel (n = 9); pemetrexed (n = 6); and others (n = 16). The DCR and OS were not significantly different between the two groups. The PFS of the monotherapy group was longer than that of the combination therapy group (mPFS: 9.6 vs. 4.6 months, P = 0.01). Univariate and multivariate analyses suggested that LDH and sex were independent prognostic factors of PFS. In the second-line therapy subgroup of 38 patients, OS and PFS were not significantly different between the two groups. In the subgroup of 46 patients treated beyond the 2nd line, the monotherapy group had a longer PFS (mPFS: 9.6 vs. 4.2 months, P = 0.01). The incidence of any-grade adverse events was not significantly different between the monotherapy group and the combination therapy group (19.2 vs. 18.9%, P = 1.000). One patient in the PD-1 inhibitor plus chemotherapy group died of immune-related pneumonitis.ConclusionThe clinical outcomes of PD-1 inhibitor plus chemotherapy as second-line or later therapy were similar to those of PD-1/PD-L1 inhibitor alone in advanced NSCLC.

Incidence and Risk of Colitis With Programmed Death 1 Versus Programmed Death Ligand 1 Inhibitors for the Treatment of Cancer

Colitis is a major immune-related adverse event associated with programmed death 1 (PD-1) and programmed death-ligand 1 (PD-L1) inhibitors, but the risk of colitis with PD-1 versus PD-L1 inhibitors is not well characterized. We performed a meta-analysis for the incidence of all grade and grade 3-4 colitis with PD-1 inhibitor (nivolumab, pembrolizumab, and cemiplimab) or PD-L1 inhibitor (atezolizumab, avelumab, and durvalumab) monotherapy using a fixed effects model. We also conducted subgroup meta-analyses of non-small cell lung cancer (NSCLC) or urothelial carcinoma (UC) trials, and a network meta-analysis of randomized trials comparing PD-1 or PD-L1 inhibitors with docetaxel for NSCLC. We also analyzed the Food and Drug Administration Adverse Event Reporting System database to estimate the reporting odds ratio of each medication. PD-1 inhibitors were associated with a higher incidence of all grade and grade 3-4 colitis compared with PD-L1 inhibitors in the analysis of all cancer types [1.49% vs. 0.83%, relative risk; 1.80, 95% confidence interval (CI); 1.22-2.67 for all grade colitis, and 0.85% vs. 0.34%, relative risk; 2.52, 95% CI; 1.46-4.37 for grade 3-4 colitis]. The meta-analyses of NSCLC and UC trials, and the network meta-analysis of NSCLC trials were also suggestive of a higher risk of colitis with PD-1 versus PD-L1 inhibitors. The reporting odds ratio of colitis with PD-1 versus PD-L1 inhibitors was 1.80 (95% CI; 1.53-2.14). In this meta-analysis of clinical trials exploring PD-1 and PD-L1 inhibitors in solid tumors, PD-1 inhibitors were associated with a higher risk of colitis.

Bioengineering the Oxygen-Deprived Tumor Microenvironment Within a Three-Dimensional Platform for Studying Tumor-Immune Interactions.

Oxygen deprivation within tumors is one of the most prevalent causes of resilient cancer cell survival and increased immune evasion in breast cancer (BCa). Current in vitro models do not adequately mimic physiological oxygen levels relevant to breast tissue and its tumor-immune interactions. In this study, we propose an approach to engineer a three-dimensional (3D) model (named 3D engineered oxygen, 3D-O) that supports the growth of BCa cells and generates physio- and pathophysiological oxygen levels to understand the role of oxygen availability in tumor-immune interactions. BCa cells (MDA-MB-231 and MCF-7) were embedded into plasma-derived 3D-O scaffolds that reflected physio- and pathophysiological oxygen levels relevant to the healthy and cancerous breast tissue. BCa cells grown within 3D-O scaffolds were analyzed by flow cytometry, confocal imaging, immunohistochemistry/immunofluorescence for cell proliferation, extracellular matrix protein expression, and alterations in immune evasive outcomes. Exosome secretion from 3D-O scaffolds were evaluated using the NanoSight particle analyzer. Peripheral blood mononuclear cells were incorporated on the top of 3D-O scaffolds and the difference in tumor-infiltrating capabilities as a result of different oxygen content were assessed by flow cytometry and confocal imaging. Lastly, hypoxia and Programmed death-ligand 1 (PD-L1) inhibition were validated as targets to sensitize BCa cells in order to overcome immune evasion. Low oxygen-induced adaptations within 3D-O scaffolds validated known tumor hypoxia characteristics such as reduced BCa cell proliferation, increased extracellular matrix protein expression, increased extracellular vesicle secretion and enhanced immune surface marker expression on BCa cells. We further demonstrated that low oxygen in 3D-O scaffolds significantly influence immune infiltration. CD8+ T cell infiltration was impaired under pathophysiological oxygen levels and we were also able to establish that hypoxia and PD-L1 inhibition re-sensitized BCa cells to cytotoxic CD8+ T cells. Bioengineering the oxygen-deprived BCa tumor microenvironment in our engineered 3D-O physiological and tumorous scaffolds supported known intra-tumoral hypoxia characteristics allowing the study of the role of oxygen availability in tumor-immune interactions. The 3D-O model could serve as a promising platform for the evaluation of immunological events and as a drug-screening platform tool to overcome hypoxia-driven immune evasion.

Expression of AKT and p-AKT protein in lung adenocarcinoma and its correlation with PD-L1 protein and prognosis.

BackgroundThe PI3K/AKT/mTOR signaling pathway were significantly associated with EGFR mutation in lung adenocarcinoma (LUAD), but its correlation with PD-L1 protein and prognosis are not clear. The aim of this study was to evaluate the expression of AKT and phosphorylated AKT (p-AKT) in LUAD and its correlation with programmed death ligand-1 (PD-L1); and to analyze the factors affecting LUAD prognosis.MethodsThe expression of AKT, p-AKT, and PD-L1 was examined using immunohistochemistry in LUAD tissues from 110 patients who underwent surgical treatment.ResultsAKT protein expression was examined in 64.5% (71/110) of the LUAD samples, and p-AKT protein expression was examined in 44.5% (49/110) of the LUAD samples. The positive rate of PD-L1 at TC1/2/3 was 38.2% (42/110). AKT and p-AKT expression was significantly associated with epidermal growth factor receptor (EGFR) mutation (P=0.016, P=0.014 respectively). Pearson’s correlation analysis indicated a negative correlation of p-AKT with PD-L1 protein (P=0.022). Out of the 62 patients with EGFR mutation, the expression of PD-L1 was negatively correlated with that of p-AKT protein (P=0.032). The expressions of AKT and p-AKT were not associated with prognosis. Multivariate analysis showed that tumor-node-metastasis (TNM) stage (P=0.013) and differentiation (P=0.046) were independent prognostic factors for overall survival.ConclusionsPI3K/AKT/mTOR in the downstream pathway of EGFR may negatively regulate the expression of PD-L1, which may partly explain why patients with EGFR mutation respond poorly to PD-1/PD-L1 inhibitors.

The prediction potential of neutrophil-to-lymphocyte ratio for the therapeutic outcomes of programmed death receptor-1/programmed death ligand 1 inhibitors in non-small cell lung cancer patients: A meta-analysis.

Background:Programmed death receptor-1 (PD-1)/programmed death ligand 1 (PD-L1) inhibitors have been demonstrated to improve the prognosis of patients with advanced non-small cell lung cancer (NSCLC) compared with chemotherapy. However, there were still some non-responders. Thus, how to effectively screen the responder may be an important issue. Recent studies revealed the immune-related indicator, neutrophil-lymphocyte ratio (NLR), may predict the therapeutic effects of anti-PD1/PD-L1 antibodies; however, the results were controversial. This study was to re-evaluate the prognostic potential of NLR for NSCLC patients receiving PD1/PD-L1 inhibitors by performing a meta-analysis.Methods:Eligible studies were identified by searching online databases of PubMed, EMBASE and Cochrane Library. The predictive values of NLR for overall survival, (OS), progression free survival (PFS) and overall response rate (ORR) were estimated by hazard ratio (HR) with 95% confidence interval (CI).Results:Twenty-four studies involving 2196 patients were included. The pooled analysis demonstrated that elevated NLR before PD-1/PD-L1 inhibitor treatment was a predictor of poor OS (HR = 2.17; 95% CI: 1.64 – 2.87, P < .001), PFS (HR = 1.54; 95% CI: 1.34 – 1.78, P < .001) and low ORR (HR = 0.64; 95% CI: 0.44 – 0.95, P = .027) in NSCLC patients. Subgroup analysis revealed the predictive ability of NLR for OS and PFS was not changed by ethnicity, sample size, cut-off, HR source, study design or inhibitor type (except the combined anti-PD-L1 group); while its association with ORR was only significant when the cut-off value was less than 5 and the studies were prospectively designed.Conclusion:Our findings suggest patients with lower NLR may benefit from the use of PD-1/PD-L1 inhibitors to prolong their survival period.

Abstract 2017: Association of digital and manual quantification of tumor PD-L1 expression with outcomes in nivolumab-treated patients

Abstract Background: Programmed death ligand 1 (PD-L1) expression on tumor cells (TC), detected by immunohistochemistry (IHC), is associated with response to programmed death-1 (PD-1)/PD-L1 inhibitors in some tumor types. Manual review of PD-L1–positive (PD-L1+) tumors can be subjective, with the potential for misclassification of PD-L1–low tumors as PD-L1–negative due to weak positivity. We compared artificial-intelligence (digital) and manual scoring methods and assessed the association of PD-L1 expression with clinical outcomes in nivolumab (NIVO)-treated patients with urothelial carcinoma (UC) and melanoma (MEL). Methods: PD-L1 expression was determined in baseline samples from NIVO monotherapy-treated patients with UC (CM275, NCT02387996) and MEL (CM067, NCT01844505; CM238, NCT02388906) using the Dako PD-L1 IHC 28-8 pharmDx assay. PD-L1+ TC were scored using digital (PathAI research platform) and manual (LabCorp) methods. Prevalence of tumors with PD-L1+ TC ≥ 1% and ≥ 5% and associations between PD-L1 expression and outcomes with NIVO were evaluated. Results: Prevalence of UC and MEL tumors with ≥ 1% and ≥ 5% PD-L1+ TC was higher for digital vs manual scoring (Table). For all samples, digital and manual scoring was associated with response to NIVO for PD-L1 ≥ 1% and ≥ 5%, and associations were similar between digital and manual scoring (Table). Digital and manual PD-L1 scoring correlated across samples from all trials (Kendall's tau range: 0.57–0.62). TablePrevalence PD-L1+ TC ≥ 1%, n (%)Evaluable samples, nDigitalManualP valueSamples ≥ 1% by digital onlyCM275241166 (69)113 (47)1.61 × 10−658 (24)CM067264173 (66)160 (61)0.27936 (14)CM238377307 (81)259 (69)7.61 × 10−566 (18)PD-L1+ TC ≥ 1% vs &amp;lt; 1%DigitalManualORR, odds ratio (95% CI)CM275a2.15 (0.98–4.70)1.60 (0.82–3.14)CM067b1.99 (1.19–3.35)1.89 (1.12–3.18)Survival, hazard ratio (95% CI)CM275 (OS)a0.67 (0.48–0.92)0.66 (0.48–0.90)CM067 (OS)b0.57 (0.41–0.80)0.71 (0.50–1.00)CM238 (RFS)c0.53 (0.36–0.77)0.83 (0.57–1.21)Prevalence PD-L1+ TC ≥ 5%, n (%)Evaluable samples, nDigitalManualP valueSamples ≥ 5% by digital onlyCM27524190 (37)74 (31)0.14928 (12)CM067264103 (39)76 (29)0.01736 (14)CM238377234 (62)139 (37)7.54 × 10−12104 (28)PD-L1+ TC ≥ 5% vs &amp;lt; 5%DigitalManualORR, odds ratio (95% CI)CM275a3.50 (1.76–6.98)2.37 (1.18–4.73)CM067b2.33 (1.40–3.86)1.77 (1.01–3.09)Survival, hazard ratio (95% CI)CM275 (OS)a0.50 (0.36–0.71)0.58 (0.41–0.83)CM067 (OS)b0.67 (0.47–0.96)0.74 (0.51–1.09)CM238 (RFS)c0.50 (0.35–0.70)0.52 (0.36–0.76)Database lock 2019: CM275, June 14; CM067, January 18; CM238, April 3.aAdjusted for ECOG performance status, liver metastatic status, and hemoglobin.bAdjusted for ECOG performance status, liver metastatic status, lactate dehydrogenase, and BRAF mutation.cAdjusted for ECOG performance status, AJCC stage, lactate dehydrogenase, and BRAF mutation.AJCC, American Joint Committee on Cancer; CI, confidence interval; ECOG, Eastern Cooperative Oncology Group; ORR, objective response rate; OS, overall survival; PD-L1, programmed death ligand 1; RFS, recurrence-free survival; TC, tumor cells. Conclusion: In post-hoc exploratory analyses, digital scoring of PD-L1 expression identified higher prevalence of PD-L1+ tumors and shows good association with response to NIVO in UC and MEL samples compared with manual scoring. Digital quantification demonstrated higher sensitivity at low levels of PD-L1 expression and may identify patients who could benefit from NIVO. Further study of the association with clinical outcomes is warranted and exploratory studies are ongoing to assess the performance of digital scoring in additional tumor types. Citation Format: Chunzhe Duan, Michael Montalto, George Lee, Dimple Pandya, Daniel Cohen, Han Chang, Hao Tang, Nishant Agrawal, Hunter Elliott, Benjamin Glass, Ilan Wapinski, Robin Edwards, Andrew H. Beck, Vipul Baxi. Association of digital and manual quantification of tumor PD-L1 expression with outcomes in nivolumab-treated patients [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2017.

Abstract 5292: Glycogen synthase kinase-3 beta (GSK-3b) genomic alterations and increased programmed death-ligand 1 (PD-L1) expression in advanced malignancies

Abstract Background: GSK-3β, a serine/threonine kinase, has been implicated in the pathogenesis of many cancers. Aberrant expression of GSK-3β promotes tumor growth and chemotherapy resistance. GSK-3β phosphorylates target pro-oncogenes (C-Jun and C-myc), as well as non-glycosylated forms of PD-L1 leading to its proteasome degradation (Li CW Nat Commun 2016). GSK-3β tumor genomic alterations have been described, yet are not well-characterized. Characterizing alterations and functional impact can guide patient selection for treatment with GSK-3β inhibitors and related combinations in clinical development, including 9-ING-41, a first-in-class, selective small molecule GSK-3β inhibitor currently in phase 1/2 clinical trial (NCT03678883). Methods: Publicly-available tumor genomic data from cBioPortal was curated and analyzed. For each tumor with a GSK-3β alteration, histology and GSK-3β protein change/copy number variation (CNV) were obtained. A second cohort of tumors obtained from Caris Life Sciences (n=73,324) was interrogated for GSK-3β genomic alterations and PD-L1 expression (assessed via SP-142 antibody on tumor cells, cutoff used was 5%). Chi-square test was used to assess significance between PD-L1 expression of GSK3β-mutated tumors and that of GSK3β-wild type (wt) tumors. Results: Of 46,237 cBioPortal tumors, 430 (1%) tumors had a GSK3β mutation or CNV. Similarly, of 73,324 samples from Caris, 819 (1%) tumors had GSK3β mutations. When combining the data from both cohorts, the histologies with most frequent GSK3β mutations were uterine endometrioid carcinoma (4%), non-melanoma skin cancer (3%), uterine neoplasms (3%), and melanoma (2%). Overall, top protein changes included R396Q (n=44), H310Q (n=40), R418C (n=16), and S215L (n=15). Of the top mutated loci, R96 (n=14) and R180 (n=12) are located in a key binding pocket for phosphoprotein GSK3β substrates. The association between PD-L1 expression and GSK3β mutations was evaluated in 55,138 cases. The frequency of PD-L1 expression was significantly higher among GSK3β-mutated tumors compared to wt in colorectal cancer (8% vs. 4%, p=0.02), endometrial cancer (11% vs. 7%, p=0.05), melanoma (42% vs. 23%, p=0.01), ovarian surface epithelial carcinoma (20% vs. 7%, p=0.001), and uterine sarcoma (40% vs. 8%, p=0.005). Among these five histologies, 49 tumors had GSK3β mutations and were positive for PD-L1, and the top mutated residues were H310Q (n=5) and S215L (n=3). Conclusions: In an assessment of over 100,000 tumor samples, GSK3β mutations were most frequently detected in uterine endometrioid carcinoma, non-melanoma skin cancer, uterine neoplasms, and melanoma. GSK3β mutations were associated with a higher frequency of PD-L1 expression in selected tumors. These results may have implications in the selection of patients for treatment with novel targeted therapies such as GSK3β inhibitors and PD-L1 inhibitors. Citation Format: Brittany A. Borden, Joanne Xiu, Yasmine Baca, Pilar Ramos, Francis J. Giles, Andrew Mazar, Fabio Tavora, Howard Safran, Wafik S. El-Deiry, Benedito A. Carneiro. Glycogen synthase kinase-3 beta (GSK-3b) genomic alterations and increased programmed death-ligand 1 (PD-L1) expression in advanced malignancies [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5292.

Temporal evolution of programmed death-ligand 1 expression in patients with non-small cell lung cancer.

Background/AimsProgrammed death-ligand 1 (PD-L1) expression, a validated predictive biomarker for anti-PD-1/PD-L1 inhibitors, is reported to change over time. This poses challenges during clinical application in non-small cell lung cancer.MethodsThis study included patients with non-small cell lung cancer who underwent surgery or biopsy and evaluation of PD-L1 expression in tumor cells via immunohistochemistry more than twice. We set the threshold of PD-L1 positivity to 10% and categorized patients into four groups according to changes in PD-L1 expression. Clinicopathologic information was collected from medical records. Statistical analyses, including Fisher’s exact test and log-rank test, were performed.ResultsOf 109 patients, 38 (34.9%) and 45 (41.3%) had PD-L1 positivity in archival and recent samples, respectively. PD-L1 status was maintained in 78 (71.6%) patients, but changed in 31 (28.4%), with 19 (17.4%) from negative to positive. There were no significant differences in characteristics between patients who maintained PD-L1 negativity and whose PD-L1 status changed from negative to positive. Patients harboring PD-L1 positivity in either archival or recent samples achieved better responses (p = 0.129) and showed longer overall survival than those who maintained PD-L1 negativity when they received immune checkpoint inhibitors after platinum failure (median overall survival 14.4 months vs. 4.93 months; hazard ratio, 0.43; 95% confidence interval, 0.20 to 0.93).ConclusionsPD-L1 status changed in about one-fourth of patients. PD-L1 positivity in either archival or recent samples was predictive of better responses to immune checkpoint inhibitors. Therefore, archival samples could be used for assessment of PD-L1 status. The need for new biopsies should be decided individually.

Abstract 3416: Androgen deprivation following JAK1/2 and PD-L1 inhibition improves antitumor efficacy in mouse models of Pten-deficient prostate cancer

Abstract Recently, the tumor suppressor PTEN has been shown to function as an immune modulator and its inactivation is associated with mediating tumor immune evasion. We previously examined the effects of programmed death-ligand 1 (PD-L1) immune checkpoint blockade (ICB) in transgenic mouse models of Pten-null prostate cancer. However, anti-PD-L1 monotherapy was largely ineffective in immunologically cold castration-naïve tumors from intact mice but showed some activity when administered to castrated mice. Our previous immune profiling studies also revealed that while androgen withdrawal increased tumor inflammation, it also mediated the recruitment and accumulation of immunosuppressive cells such as regulatory T cells, M2-polarized macrophages and myeloid-derived suppressor cells (MDSCs). Interleukin-6 (IL-6)/signal transducer and activator of transcription-3 (STAT3) signaling is a key immune modulating pathway that is upregulated in both intact and androgen deprived tumors. Here, we evaluate the effectiveness of targeting PD-L1 and JAK/STAT signaling in preclinical models of Pten-null prostate cancer. Intact tumor bearing conditional Pten-knockout were treated for four weeks with an a-PD-L1 blocking antibody (clone D265A, mouse/IgG1 kappa) and/or the JAK1/2 inhibitor, AZD1480. Pharmacological treatments targeting PD-L1 and JAK1/2 (PJ) combinations were also evaluated as concurrent therapy with androgen deprivation (AD) by orchidectomy (PJ+AD), and as sequential therapy; two weeks AD followed by PJ (AD&amp;gt;PJ), and one week of PT followed by AD (PJ&amp;gt;AD). Combined PD-L1/JAK followed by AD was the only treatment combination that improved antitumor immune responses over monotherapy. Notably, flow cytometry studies showed that combined PD-L1/JAK potently abrogated PD-L1 expression in circulating dendritic cells in all settings. Evidence for enhanced antitumor immune response in PJ&amp;gt;AD was supported by increased numbers circulating effector memory CD8 T cells and CD355+CD8+ T cells (CD355 Class I MHC-restricted T cell-associated molecule (CRTAM) a marker for activated CD8 T cell), and increased CD8 T cell infiltration in tumors and a reduction of CD25+CD4+ regulatory T cells. The efficacy of the PJ&amp;gt;AD treatment combination was further tested and confirmed in a subcutaneous syngeneic allograft model using mice grafted with tumor blocks from Pten-deficient castration-resistant prostate cancer tumors. Together these results indicate that pretreatment with combined PD-L1/JAK blockade can decrease the immunosuppressive effects of androgen withdrawal and have the potential to restore antitumor immune activity in Pten-deficient prostate cancer. Citation Format: Marco A. De Velasco, Yurie Kura, Naomi Ando, Noriko Sako, Kazuko Sakai, Kazuhiro Yoshikawa, Kazuto Nishio, Hirotsugu Uemura. Androgen deprivation following JAK1/2 and PD-L1 inhibition improves antitumor efficacy in mouse models of Pten-deficient prostate cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3416.

Progress of Immunotherapy Mechanisms and Current Evidence of PD-1/PD-L1 Checkpoint Inhibitors for Non-small Cell Lung Cancer with Brain Metastasis

脑转移是非小细胞肺癌(non-small cell lung cancer, NSCLC)的常见并发症，预后较差。近年来，免疫检查点抑制剂将恶性肿瘤的治疗带入新纪元。程序性死亡因子-1(programmed death-1, PD-1)/程序性死亡因子配体-1(programmed death ligand 1, PD-L1)抑制剂通过激活自身免疫系统，产生抗肿瘤效应。PD-1/PD-L1抑制剂在NSCLC脑转移治疗中初露锋芒，但其确切疗效及最佳治疗模式仍有待进一步研究。本文针对NSCLC脑转移灶的免疫微环境，PD-1/PD-L1抑制剂在颅内的作用机制及其临床研究现状进行综述。

Adverse cardiac events in the treatment of non-small cell lung cancer with programmed death-1and programmed death-ligand 1 inhibitors: A protocol for systematic review and meta-analysis.

Background:Programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1) inhibitors are immune therapies that have shown great promise in the treatment of multiple cancers. However, immune-related adverse events of PD-1 and PD-L1 inhibitors may limit their use in non-small cell lung cancer (NSCLC). Given the rising number of clinical trials in recent years, it is essential to perform a meta-analysis to provide assess the cardiotoxicity of PD-1/ PD-L1 inhibitors in NSCLC therapy.Method and analysis:The ClinicalTrials.gov, Embase, PubMed, and Cochrane Central Register of Controlled Trials repositories will be searched from their inception to December 2019. The bibliography of the searching process will be imported into Endnote X9 software. Two reviewers independently will screen the literature, extract data, and conduct the risk of bias for every added study. The data analysis will be analyzed using Stata15.0 software. Specific adverse cardiac events will be identified, with particular attention on atrial fibrillation, cardiac arrest, cardiac failure, and pericarditis. This review will be performed as per the Preferred Reporting Item for Systematic Review and meta-analysis statement recommendations.Ethics and dissemination:This study will provide support for the cardiotoxicity linked to the treatment of NSCLC using PD-1/PD-L1 inhibitors. The data in the meta-analysis will be retrieved from completed and published clinical trials; therefore, ethical review and patient informed consent will not be required.PROSPERO number:CRD42020156397.

Anti-tumor effects of NK cells and anti-PD-L1 antibody with antibody-dependent cellular cytotoxicity in PD-L1-positive cancer cell lines.

BackgroundAlthough programmed cell death-1/programmed death-ligand 1 (PD-L1) inhibitors show remarkable antitumor activity, a large portion of patients with cancer, even those with high PD-L1-expressing tumors, do not respond to their effects. Most PD-L1 inhibitors contain modified fragment crystallizable region (Fc) receptor binding sites to prevent antibody-dependent cellular cytotoxicity (ADCC) against PD-L1-expressing non-tumor cells. However, natural killer (NK) cells have specific antitumor activity in the presence of tumor-targeting antibody through ADCC, which could enhance NK cell-induced cytotoxicity. We evaluated the antitumor efficacy of ADCC via anti-PD-L1 monoclonal antibodies (mAbs) and NK cells against several PD-L1-positive cancer cell lines.MethodsVarious cancer cell lines were used as target cell lines. Surface PD-L1 expression was analyzed by flow cytometry. IMC-001 and anti-hPD-L1-hIgG1 were tested as anti-PD-L1 mAbs with ADCC and atezolizumab as an anti-PD-L1 mAb without ADCC. NK cell cytotoxicity was measured by 51Cr-release assay and CD107a degranulation assay. Also, live cell imaging was performed to evaluate cytotoxicity in a single-cell level. NK-92-CD16 (CD16-transduced NK-92 cell line) and peripheral blood mononuclear cells from healthy donors, respectively, were used as an effector cell. FcγRIIIa (CD16a)-V158F genotyping was performed for healthy donors.ResultsWe demonstrated that the cytotoxicity of NK-92-CD16 cells toward PD-L1-positive cancer cell lines was significantly enhanced in the presence of anti-PD-L1 mAb with ADCC. We also noted a significant increase in primary human NK cell cytotoxicity against PD-L1-positive human cancer cells when cocultured with anti-PD-L1 mAb with ADCC. Moreover, NK cells expressing a FCGR3A high-affinity genotype displayed higher anti-PD-L1 mAb-mediated ADCC lysis of tumor cells than donors with a low-affinity genotype.ConclusionThese results suggest that NK cells induce an ADCC response in combination with anti-PD-L1 mAbs, which helps promote ADCC antitumor activity against PD-L1-positive tumors. This study provides support for NK cell immunotherapy against high PD-L1-expressing tumors in combination with ADCC through anti-PD-L1 mAbs.

Theoretical investigation on QSAR of (2-Methyl-3-biphenylyl) methanol analogs as PD-L1 inhibitor

Cancer is one of the most serious issues in human life. Blocking programmed cell death protein 1 and programmed death ligand-1 (PD-L1) pathway is one of the great innovations in the last few years, a few numbers of inhibitors can be able to block it. (2-Methyl-3-biphenylyl) methanol derivative is one of them. Here, the quantitative structure-activity relationship (QSAR) established twenty (2-methyl-3-biphenylyl) methanol derivatives as the programmed death ligand-1 inhibitors. Density functional theory at the B3LPY/6-31+G(d,p) level was employed to study the chemical structure and properties of the chosen compounds. Highest occupied molecular orbital energy EHOMO, lowest unoccupied molecular orbital energy ELUMO, total energy ET, dipole moment DM, absolute hardness η, absolute electronegativity χ, softness S, electrophilicity ω, energy gap ΔE, etc., were observed and determined. Principal component analysis (PCA), multiple linear regression (MLR) and multiple non-linear regression (MNLR) analysis were carried out to establish the QSAR. The proposed quantitative models and interpreted outcomes of the compounds were based on statistical analysis. Statistical results of MLR and MNLR exhibited the coefficient R2 was 0.661 and 0.758, respectively. Leave-one-out cross-validation, rm2 metric, rm2 test, and “Golbraikh & Tropsha’s criteria” analyses were applied for the validation of MLR and MNLR, which indicate two models are statistically significant and well stable with data variation in the external validation towards PD-L1. The obtained results showed that the MNLR model predicts the bioactivity more accurately than MLR, and it may be helpful and supporting for evaluation of the biological activity of PD-L1 inhibitors.

Expert consensus on PD-L1 expression testing in non-small-cell lung cancer in China

Cancer immunotherapy, especially the programmed death 1 (PD-1) and (or) programmed death ligand 1 (PD-L1) checkpoint inhibitors, has ushered in the modern oncology era and has achieved impressive success in the treatment of different tumors, including non-small-cell lung cancer (NSCLC). Yet, only a subset of patients achieved clinical benefit. Therefore, how to effectively screen the potential beneficiaries of PD-1 and (or) PD-L1 inhibitors has become a new challenge in the era of cancer immunotherapy. Clinical studies have shown that the expression level of PD-L1 in NSCLC is positively correlated with the efficacy of PD-1 and (or) PD-L1 inhibitors, and is one of the important predictive biomarkers. However, there are many challenges in PD-L1 testing. With the approving of various PD-1 and (or) PD-L1 inhibitors for immunotherapy setting of NSCLC, expert consensus of important issues regarding clinical significance of PD-L1 testing, testing time-point, as well as the standardization of PD-L1 testing procedure, including the PD-L1 testing operation steps, results' interpretation, quality control and so on, is of great significance for improving the accuracy of detection and reducing the difference between laboratories. On account to the practical questions of PD-L1 testing, this consensus was finally reached, which is based on the combination of literature, expert experience and internal discussion among committee members, in the hope of providing the guide for standardizing the PD-L1 testing and providing accurate and reliable result to screen the potential patients and predict clinical efficacy. It must be pointed out that in view of the existence of objective and complex factors of PD-L1 testing and the fact that the clinical application of PD-L1 testing is still at the early stage in China, there are still many issues need to be updated in near future based on further practice experience and research data.

Relationship between IL10 and PD-L1 in Liver Hepatocellular Carcinoma Tissue and Cell Lines

Background Despite the large-scale clinical application of programmed death-ligand 1 (PD-L1) monoclonal antibody, reduction in its clinical response rate has become a gradual problem. As such, use of PD-L1 monoclonal antibody in combination with other anticarcinoma drugs has been the main strategy in improving its efficacy. Interleukin 10 (IL10) is a recognized inflammatory and immunosuppressive factor. Previous studies have suggested that there is a link between PD-L1 and IL10. Objective This study was aimed at clarifying the relationship between PD-L1 and IL10 in liver hepatocellular carcinoma (LIHC) and whether IL10 enhances the efficacy of PD-L1 inhibitor. Methods Expression levels of PD-L1 and IL10 in carcinoma and adjacent tissues were tested by immunochemistry, Western blotting, and RT-PCR. Survival duration and follow-up data of each patient were recorded. LIHC cell lines Bel7405 and MHCC 97-H were used for in vitro experiments. Exogenous IL10 and anti-IL10 were added to cell supernatant. Expression level of PD-L1 in the LIHC cell lines was determined using Western blotting and ELISA. CCK8 and transwell assays were adopted to examine the effect of PD-L1 combined with IL10 on proliferation, invasion, and metastasis of LIHC cells. Results The survival period of patients with low expression of IL10 was longer than that of patients with high expression (P = 0.01). Overexpression of PD-L1 increased the IL10 and Met levels in LIHC tissues and cell lines. IL10 downregulated the expression level of PD-L1 and enhanced the efficacy of crizotinib via the Met signaling pathway in the LIHC cells. Conclusions A combination of IL10 and PD-L1 inhibitor holds great promise as an effective treatment for LIHC.