Soluble Programmed Cell Death Ligand Research Articles

Serum levels of soluble programmed death-1 (sPD-1) and soluble programmed death ligand 1(sPD-L1) in systemic lupus erythematosus: Association with activity and severity.

The programmed cell death-1 (PD-1)/programmed cell death ligand 1 (PD-L1) pathway is an important host immunosuppression mechanism. Soluble PD-1 (sPD-1) and PD-L1 (sPD-L1) expression regulates co-inhibitory signals in autoimmune disorders. Here, we evaluated whether serum sPD-1 and sPD-L1 are involved in immune dysfunction and assessed its relationship with SLE. Blood samples were obtained from 130 patients with SLE and 44 healthy controls. Serum sPD-1 and sPD-L1 were tested by enzyme-linked immunosorbent assay (ELISA). Relevant immune parameters were analysed. Both serum sPD-1 and sPD-L1 were significantly higher in the SLE patients than in the controls. A series of severe disease clinical manifestations and laboratory features such as presence of decreased complement component 3, complement component 4 and SLEDAI >8 were associated with elevated sPD-1 and sPD-L1. Our study suggests that abnormal sPD-1 and sPD-L1 expression may be involved in the imbalance of immune regulation in SLE.

Trophoblast-secreted soluble-PD-L1 modulates macrophage polarization and function

Decidual macrophages are in close contact with trophoblast cells during placenta development, and an appropriate crosstalk between these cellular compartments is crucial for the establishment and maintenance of a healthy pregnancy. During different phases of gestation, macrophages undergo dynamic changes to adjust to the different stages of fetal development. Trophoblast-secreted factors are considered the main modulators responsible for macrophage differentiation and function. However, the phenotype of these macrophages induced by trophoblast-secreted factors and the factors responsible for their polarization has not been elucidated. In this study, we characterized the phenotype and function of human trophoblast-induced macrophages. Using in vitro models, we found that human trophoblast-educated macrophages were CD14+ CD206+ CD86- and presented an unusual transcriptional profile in response to TLR4/LPS activation characterized by the expression of type I IFN-β expression. IFN-β further enhances the constitutive production of soluble programmed cell death ligand 1 (PD-L1) from trophoblast cells. PD-1 blockage inhibited trophoblast-induced macrophage differentiation. Soluble PD-L1 (sPD-L1) was detected in the blood of pregnant women and increased throughout the gestation. Collectively, our data suggest the existence of a regulatory circuit at the maternal fetal interface wherein IFN-β promotes sPD-L1 expression/secretion by trophoblast cells, which can then initiate a PD-L1/PD-1-mediated macrophage polarization toward an M2 phenotype, consequently decreasing inflammation. Macrophages then maintain the expression of sPD-L1 by the trophoblasts through IFN-βproduction induced through TLR4 ligation.

Dynamic monitoring of serum soluble programmed cell death ligand 1 as a response predictor to chemotherapy in metastatic or recurrent gastrointestinal cancer

BackgroundBiomarkers in serum may have important clinical implications for personalized medicine, including therapeutic guidance, and monitoring of recurrence. The role of programmed cell death ligand 1 (PD-L1) expression as a tumor biomarker remains controversial. In this study, we aimed at determining the changes of soluble PD-L1 (sPD-L1) during first-line chemotherapy and assessing the association with treatment response and progression-free survival (PFS) of patients with advanced gastrointestinal cancer.MethodsBlood samples from 115 gastrointestinal cancer patients who have not received any previous systemic chemotherapy for recurrent or metastatic disease were collected at the time of diagnosis and each response evaluation. Serum of sPD-L1 expression was tested by enzyme-linked immunosorbent assay (ELISA). The associations between the baseline level of serum sPD-L1 and clinical-pathological characteristics and prognosis were analyzed. we further dynamically monitored the level change of serum sPD-L1 during treatment and analyzed its relationship with clinical-pathological characteristics, chemotherapy response and prognosis.ResultsAmong 115 metastatic gastrointestinal patients, the median serum sPD-L1 level was 0.777 (range, <0.156–6.680) ng/mL. In most cases, changes in sPD-L1 level correlated with treatment response. Patients with values of serum sPD-L1 decreasing after chemotherapy had better tumor response and median PFS compared with patients with values increasing after chemotherapy (ORR, 88.3% vs. 54.0% P=0.000005 and PFS, not reached vs. 27 months, P=0.00026). D-values of sPD-L1 in patients with progressive disease (PD) were observed increasing from 0.406 to 1.097 ng/mL between pre- and post-chemotherapy, while in those with better tumor response D-values decreased from 1.153 to 0.791 ng/mL after chemotherapy compared with baseline. In the logistic regression analysis, the change of sPD-L1 levels in serum after chemotherapy were found to be a prognostic factor for treatment response and PFS in the multivariate analysis.ConclusionsThese results showed for the first time that sPD-L1 in serum samples of patients with advanced gastrointestinal cancer were changed after chemotherapy and increased serum sPD-L1 levels were poor prognostic factors for both tumor response and PFS of patients. Dynamic monitoring of serum sPDL1 after treatment may be served as a potential predictor to treatment response in gastrointestinal cancer patients.

Predictive Value of Soluble PD-1, PD-L1, VEGFA, CD40 Ligand and CD44 for Nivolumab Therapy in Advanced Non-Small Cell Lung Cancer: A Case-Control Study.

A large interindividual variability has been observed in anti Programmed cell Death 1 (anti-PD1) therapies efficacy. The aim of this study is to assess the correlation of soluble PD-1 (sPD-1), soluble Programmed cell Death Ligand 1 (sPD-L1), Vascular Endothelial Growth Factor A (VEGFA), soluble CD40 ligand (sCD40L) and soluble CD44 (sCD44), with survival in nivolumab-treated metastatic non-small cell lung cancer (NSCLC) patients. Plasma biomarkers were assayed at baseline and after two cycles of nivolumab. A cut-off of positivity for sPD-1, sPD-L1 and sCD40L expressions was defined as a plasma level above the lower limit of quantification. Baseline sPD-1 and sPD-L1 levels were subsequently analyzed in a control group of EGFR-mutated (Epidermal Growth Factor Receptor) NSCLC patients. Association between survival and biomarkers was investigated using Cox proportional hazard regression model. Eighty-seven patients were included (51 nivolumab-treated patients, 36 in EGFR-mutated group). In nivolumab group, baseline sPD-1, sPD-L1 and sCD40L were positive for 15(29.4%), 27(52.9%) and 18(50%) patients, respectively. We defined a composite criteria (sCombo) corresponding to sPD-1 and/or sPD-L1 positivity for each patient. In nivolumab group, baseline sCombo positivity was associated with shorter median progression-free survival (PFS) (78 days 95%CI (55–109) vs. 658 days (222-not reached); HR: 4.12 (1.95–8.71), p = 0.0002) and OS (HR: 3.99(1.63–9.80), p = 0.003). In multivariate analysis, baseline sCombo independently correlated with PFS (HR: 2.66 (1.17–6.08), p = 0.02) but not OS. In EGFR-mutated group, all patients were baseline sCombo positive; therefore this factor was not associated with survival. After two cycles of nivolumab, an increased or stable sPD-1 level independently correlated with longer PFS (HR: 0.49, 95%CI (0.30–0.80), p = 0.004) and OS (HR: 0.39, 95%CI (0.21–0.71), p = 0.002). VEGFA, sCD40L and sCD44 did not correlate with survival. We propose a composite biomarker using sPD-1and sPDL-1 to predict nivolumab efficacy in NSCLC patients. A larger validation study is warranted.

The Clinical Significance of Soluble Programmed Cell Death-Ligand 1 (sPD-L1) in Patients With Gliomas.

Background: Soluble PD-L1 (sPD-L1) in the circulation has been documented to activate global immunosuppression and is considered a predictor of negative clinical outcomes in several malignances. However, the clinical significance of sPD-L1 in the peripheral blood and cerebrospinal fluid (CSF) of patients with glioma remains unclear.Objective: The aim of this study was to detect the correlations of sPD-L1 with clinical features in brain tumors and assess the diagnostic value of this protein in gliomas.Methods: Serum samples were obtained from 73 patients with glioma, 20 patients with meningioma, and 49 healthy controls (HCs) in this study. In total, 31 CSF samples were collected from the matched glioma patients, and seven samples were collected from the matched meningioma patients. The expression of serum sPD-L1 in the glioma cohort was followed for 20 days after surgery to examine the kinetics in the circulation. Inflammatory markers were evaluated based on preoperative blood parameters. The sPD-L1 levels in the serum and CSF were determined by enzyme-linked immunosorbent assay (ELISA). The logistic regression model was used to assess the independent associations of sPD-L1 with gliomas, including high-grade gliomas.Results: Serum and CSF levels of sPD-L1 were significantly elevated in patients with gliomas compared to those with meningiomas and HCs. Additionally, increased levels of sPD-L1 were observed in relatively advanced tumors. sPD-L1 overexpression in the CSF appears to be more representative of aggressive tumor features than overexpression in the serum. For glioma diagnosis, both serum and CSF sPD-L1 showed significant value in the diagnosis and stratification of glioma, and the best diagnostic performance was obtained with serum sPD-L1 rather than blood-based inflammatory markers. In addition, a descending trend in the level of serum sPD-L1 was observed in postoperative patients.Conclusion: In gliomas, elevated circulating and CSF sPD-L1 levels are associated with aggressive biological activities. The results of the current study suggest that sPD-L1 is a promising biomarker for gliomas that can be used in clinical practice.

Determining and Incorporating the Optimal Predictive Biomarkers in Hepatocellular Carcinoma Patients Treated with Radiotherapy

Radiotherapy (RT) is one of the treatment options for treating hepatocellular carcinoma (HCC) patients. However, treatment responses to RT are heterogeneous and no robust predictive biomarker has been found. Previously, our institution reported the possibility of soluble programmed cell death ligand-1 (sPD-L1), plasma cell-free DNA (cfDNA), inter-alpha inhibitor H4 (ITIH4), interleukin (IL)-6, and IL-10 as predictive biomarkers after RT. However, using a single biomarker to predict treatment outcomes has limitations since the heterogeneity of the tumor and the host-immune system both affect tumor response and oncologic outcomes. Thus, we investigated the optimal biomarkers and incorporated them to predict treatment outcomes in HCC patients treated with RT. Hundred-four HCC patients treated with RT between July 2016 and October 2018 were prospectively enrolled. Conventional RT was performed in all patients, with a median RT dose of 100 Gy (range, 60–100 Gy) for GTV and a median RT dose of 60 Gy (range, 45–60 Gy) for PTV. Peripheral blood was collected at baseline and after RT. A total of six biomarkers, sPD-L1, IL-10, IL-6, cfDNA, ITIH4 and IFN-γ, were analyzed. Median follow up period was 14.7 months (range, 2.3–28.9 months). Median age was 61 (range, 33–80), 44 patients (44.4%) had single tumor and the median tumor size was 6.5 cm (range, 1.3–21.0 cm). Nine patients had node-positive disease and 52 patients had portal vein tumor thrombosis or invasion. One-year overall survival rates and progression-free rates were 85.1% and 38.6%, respectively. The most common first pattern of failure was regional only failure, followed by distant only failure. Recursive partitioning analysis revealed four prognostic groups for regional failure based on sPD-L1, IL-10, and number of hepatic lesions: group 1, sPD-L1 < 8.17 pg/mL; group 2, sPD-L1 ≥ 8.17 pg/mL, single tumor; group 3, sPD-L1 ≥ 8.17 pg/mL, multiple tumors, IL-10 < 3.64 pg/mL; group 4, sPD-L1 ≥ 8.17 pg/mL, multiple tumors, IL-10 ≥ 3.64 pg/mL. Regional failure rate was highest in group 4 and lowest in group 1 (p < 0.001). Also, three prognostic groups for progression using post-RT biomarker values were defined based on cfDNA and sPD-L1: group 1, cfDNA < 4.47 μg/mL, sPD-L1 < 19.38 pg/mL; group 2, cfDNA < 4.47 μg/mL, sPD-L1 ≥ 19.38 pg/mL; group 3, cfDNA ≥ 4.47 μg/mL. Progression rate was highest in group 3 and lowest in group 1 (p < 0.001). This is the first study to incorporate multiple blood-based biomarkers to predict treatment outcomes in HCC patients who received RT. Baseline sPD-L1 and IL-10 level for regional recurrence and post-RT cfDNA and sPD-L1 level for progression showed potential as predictive biomarkers. However, the potential to predict survival or overall progression remains limited and further validation in a larger cohort is needed.

Elevated levels of soluble PD-L1 are associated with reduced recurrence in papillary thyroid cancer

To date, no research evaluating the predictive capabilities of soluble programmed cell death-ligand 1 (sPD-L1) in thyroid cancer patients has been performed. We aimed to investigate the prognostic significance of sPD-L1 expression in papillary thyroid cancer (PTC) and to evaluate the association between sPD-L1 levels with tumoural PD-L1 expression and patient outcomes. Pre-treatment levels of serum and plasma sPD-L1 were measured by ELISA in 101 PTC patients. Tissue microarrays were stained with an anti-PD-L1 antibody, clone SP263 (Ventana). The median serum sPD-L1 concentration in PTC patients was significantly higher compared to healthy controls (P = 0.028). An increased incidence of extrathyroidal extension was significantly associated with an elevated serum sPD-L1 level (P = 0.015). Patients with high serum sPD-L1 levels had significantly shorter median disease-free survival (DFS) as compared to those with low sPD-L1 levels (P = 0.011). Following multivariate analysis, serum sPD-L1 was the only statistically significant predictor for DFS. Patients with both positive serum and tumoural PD-L1 expression had a significantly shorter DFS than those in any other subgroup (P = 0.007). Our study is the first to confirm that sPD-L1 concentration is significantly associated with patient outcome in PTC. Soluble PD-L1 may provide clinicians with a non-invasive biomarker that can lessen dependence on tissue biopsies and diagnose aggressive thyroid cancers at a more treatable stage.

Clinical significance of soluble programmed cell death-1 and soluble programmed cell death-ligand 1 in patients with locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy.

BackgroundInhibition of the programmed cell death-1/programmed cell death-ligand 1 (PD-1/PD-L1) axis in combination with radiotherapy may be a promising approach to treat cancer. In the present study, we aimed to evaluate serum soluble PD-1/PD-L1 levels in patients with advanced rectal cancer treated with neoadjuvant chemoradiotherapy (CRT).MethodsSerum soluble PD-L1 and PD-1 levels were measured using an enzyme-linked immunosorbent assay before and after CRT in 117 patients with low rectal cancer. Changes in the levels of sPD-L1/PD-1 after CRT, and the correlation between sPD-L1/PD-1 level and clinicopathological characteristics or disease-free survival (DFS) were evaluated.ResultssPD-L1 levels significantly increased after CRT (p < 0.0001), whereas sPD-1 levels did not change significantly (p = 0.1050). High sPD-L1 before CRT was significantly associated with younger age (p = 0.044), and after CRT, with lymphovascular invasion (p = 0.021). High sPD-1 before and after CRT was significantly associated with a longer distance of the tumor from the anal verge (both p < 0.001). There was no correlation between sPD-L1 level and local PD-L1 expression on stromal immune cells. High sPD-L1 level after CRT tended to be associated with worse DFS (p = 0.0752). The multivariate analysis could not demonstrate an independent association for sPD-L1 levels after CRT with DFS.ConclusionsSignificant increase of sPD-L1 levels after CRT suggests that anti-PD-L1 therapy might be a potential treatment strategy in combination with CRT in advanced rectal cancer.

Soluble programmed death-ligand 1 are highly expressed in peripheral T-cell lymphoma: a biomarker for prognosis

ABSTRACTPurposeTo investigate the role of soluble programmed cell death ligand 1 (sPD-L1) protein in plasma of patients with Peripheral T-cell lymphoma (PTCL).MethodsIn total, 80 patients with newly diagnosed PTCL and 75 healthy controls were enrolled. Levels of sPD-L1 were measured by ELISA at diagnosis and after 3–8 courses of chemotherapy. The expression of PD-L1 in tumor tissues from nine PTCL patients was also detected.ResultssPD-L1 was higher in PTCL patients at diagnosis compared to healthy subjects (P < 0.0001). Patients in the intermediate/high-risk disease group had a higher level of sPD-L1 than patients in the low-risk group (P = 0.0003). Elevated sPD-L1 (≥176.30 pg/ml) was the only biomarker for PTCL that retain statistical significance in multivariate analysis. Patients in the low-risk group with sPD-L1 ≥ 176.30 pg/ml had an adverse prognosis. Histological analysis showed that the expression of PD-L1 in tissues was positively correlated with sPD-L1 levels in plasma (Spearman = 0.9177, P = 0.0013).ConclusionssPD-L1 is a sensitive biomarker predicting clinical outcomes in PTCL.

Soluble PD-L1 Expression in Circulation as a Predictive Marker for Recurrence and Prognosis in Gastric Cancer: Direct Comparison of the Clinical Burden Between Tissue and Serum PD-L1 Expression.

This study assessed programmed cell death ligand 1 (PD-L1) expression in primary tissues and soluble PD-L1 (sPD-L1) concentration in matched preoperative serum in gastric cancer (GC) patients to perform direct comparison between tissue and serum PD-L1 expression and to clarify the prognostic implication in GC. The study enrolled 180 GC patients who underwent surgery for GC at the authors' institution. The study evaluated tissue PD-L1 expression using immunohistochemistry and quantified sPD-L1 concentration in preoperative serum using enzyme-linked immunosorbent assay in GC patients. The findings showed that PD-L1 was overexpressed in GC tissues compared with normal mucosa. Tissue PD-L1 expression was significantly higher in the GC patients with advanced T stage, presence of lympho-vascular invasion, lymph node metastasis, and peritoneal metastasis. Furthermore, elevated tissue PD-L1 expression was significantly associated with poor prognosis for overall survival (OS) and disease-free survival (DFS). Serum sPD-L1 was significantly higher in the GC patients than in the healthy volunteers. Although serum sPD-L1 was not correlated with any clinicopathologic factors, the patients with high serum sPD-L1 showed poorer OS and DFS than those with low sPD-L1. Multivariate analyses showed that both elevated tissue PD-L1 and serum sPD-L1 were independent prognostic factors for poor OS [tissue PD-L1: hazard ratio (HR), 4.28; 95% confidence interval (CI), 1.43-12.8; P = 0.0094 vs. serum sPD-L1: HR, 11.2; 95% CI, 3.44-36.7; P = 0.0001] and poor DFS (tissue PD-L1: HR, 6.96; 95% CI, 2.48-19.6; P = 0.0002 vs. serum sPD-L1: HR, 8.7; 95% CI, 3.16-23.9; P < 0.0001) for the GC patients. Furthermore, infiltrative CD8- and Foxp3-positive T cells were significantly increased in the GC patients with elevated tissue PD-L1 expression. Both serum sPD-L1 and tissue PD-L1 expression may serve as predictive biomarkers for recurrence and prognosis in GC patients.

Elevated serum soluble programmed cell death ligand 1 concentration as a potential marker for poor prognosis in small cell lung cancer patients with chemotherapy

BackgroundPotential relationship between serum soluble programmed cell death ligand 1 and prognosis of small cell lung cancer is not well explored. The aim of the study was to reveal the prognostic significance of serum soluble programmed cell death ligand 1 in patients with small cell lung cancer.MethodsA total of 250 small cell lung cancer patients and 250 controls were included. Research information was obtained from their medical records. Blood samples were collected on admission. Serum concentration of programmed cell death ligand 1 was measured using Enzyme-Linked Immunosorbent Assay. The patients underwent cisplatin-etoposide chemotherapy with a maximum of six cycles. Subsequently, they were followed-up for 12 months, and therapeutic response and cancer death were recorded.ResultsSerum concentration of programmed cell death ligand 1 was higher in the patients than in the controls on admission (P < 0.001). After chemotherapy, 112 patients had no response to this therapy. In the 12-month follow up period, 118 patients died due to this cancer. Multivariate Cox regression model revealed that the higher serum concentration of programmed cell death ligand 1 on admission was associated with the higher risk of no response to chemotherapy or cancer caused death (HR: 1.40, 95% CI: 1.05 ~ 1.87; HR: 1.43, 95% CI: 1.08 ~ 1.87).ConclusionElevated serum concentration of soluble programmed cell death ligand 1 might be an independent risk factor for non-response to chemotherapy and cancer caused death in small cell lung cancer patients.

Pre-treatment serum levels of soluble programmed cell death-ligand 1 predict prognosis in patients with hepatitis B-related hepatocellular carcinoma.

Anti-programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) therapy has shown promise in tumor immunotherapy. Our objectives were to measure pre-treatment serum-soluble PD-L1 (sPD-L1) levels and to assess the relationships between sPD-L1 levels and clinical characteristics, prognosis, and tumor tissue PD-L1 expression in patients with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). Pre-treatment serum sPD-L1 levels were measured with an enzyme-linked immunosorbent assay (ELISA) in 81 patients with HBV-related HCC and compared to those in 49 healthy controls. The association between serum sPD-L1 levels and prognosis was assessed using survival analysis. The correlation between paired serum sPD-L1 levels and tumor PD-L1 expression (in resected tissue homogenates) was assessed in a separate group of 20 patients with HBV-related HCC. Median sPD-L1 concentration in patients with HBV-related HCC was 5.129 (range 0.140-12.391) ng/mL and in healthy controls was 0.836 (range 0.105-2.168) ng/mL (p < 0.001). On multivariate analysis, sPD-L1 levels were significant independent predictors of disease-free survival (hazard ratio [HR] 3.503; 95% confidence interval [CI], 1.559-7.871; p = 0.002) and overall survival (HR 3.399; 95% CI 1.308-8.831; p = 0.012). Positive correlation (r = 0.527, p = 0.017) between serum sPD-L1 and tumor PD-L1 expression was observed. Tumor expression of PD-L1 was significantly higher in those with serum sPD-L1 concentrations above vs. below the median level of 5.471ng/ml (p = 0.012). In patients with HBV-related HCC, serum sPD-L1 concentrations were elevated, and positively correlated with tumor PD-L1 expression. Lower pre-treatment serum sPD-L1 levels were predictors of more favorable disease-free and overall survival. Serum sPD-L1 testing has a potential role in HBV-related HCC disease assessment, systemic therapy choices and survival prediction.

Soluble Programmed Cell Death Ligand 1 as a Novel Biomarker for Nivolumab Therapy for Non–Small-cell Lung Cancer

BackgroundBiomarkers for predicting the effect of anti–programmed cell death 1 (PD-1) monoclonal antibody against non–small-cell lung cancer (NSCLC) are urgently required. Although it is known that the blood levels of soluble programmed cell death ligand 1 (sPD-L1) are elevated in various malignancies, the nature of sPD-L1 has not been thoroughly elucidated. We investigated the significance of plasma sPD-L1 levels as a biomarker for anti–PD-1 monoclonal antibody, nivolumab therapy. Patients and MethodsThe present prospective study included 39 NSCLC patients. The patients were treated with nivolumab at the dose of 3 mg/kg every 2 weeks, and the effects of nivolumab on NSCLC were assessed according to the change in tumor size, time to treatment failure (TTF), and overall survival (OS). The baseline plasma sPD-L1 concentration was determined using an enzyme-linked immunosorbent assay. ResultsThe area under the curve of the receiver operating characteristic curve was 0.761. The calculated optimal cutoff point for sPD-L1 in the plasma samples was 3.357 ng/mL. Of the 39 patients, 59% with low plasma sPD-L1 levels achieved a complete response or partial response and 25% of those with high plasma sPD-L1 levels did so. In addition, 22% of the patients with low plasma sPD-L1 levels developed progressive disease compared with 75% of those with high plasma sPD-L1 levels. The TTF and OS were significantly longer for those patients with low plasma sPD-L1 levels compared with the TTF and OS for those with high plasma sPD-L1 levels. ConclusionThe clinical benefit from nivolumab therapy was significantly associated with the baseline plasma sPD-L1 levels. Plasma sPD-L1 levels might represent a novel biomarker for the prediction of the efficacy of nivolumab therapy against NSCLC.

High Serum Level of Soluble Programmed Death Ligand 1 is Associated With a Poor Prognosis in Hodgkin Lymphoma

Blockade of the programmed cell death 1-programmed cell death ligand 1 pathway is a new and promising therapeutic approach in Hodgkin lymphoma (HL). To our knowledge, the impact of soluble programmed cell death ligand 1 (sPD-L1) serum levels on HL patient prognosis has not yet been investigated. In this study, the prognostic value of sPD-L1 was assessed in patients with HL. We measured serum sPD-L1 levels and identified their prognostic value in 108 newly diagnosed HL patients using an enzyme-linked immunosorbent assay (ELISA). We found higher serum sPD-L1 concentrations in HL patients than in healthy controls. The best sPD-L1 cutoff value for predicting disease progression risk was 25.1674 ng/ml. The 4-year progression-free survival (PFS) rates for the high-sPD-L1 and low-sPD-L1 groups were 78.8% and 93.3%, respectively. Multivariate survival analysis showed that advanced stage and higher sPD-L1 levels (>25.1674 ng/ml) were independent prognostic factors for shorter PFS. In addition, higher sPD-L1 levels were positively correlated with advanced stage and negatively correlated with peripheral blood monocyte number. The serum sPD-L1 level is an independent prognostic factor for PFS in HL patients and may allow identification of a subgroup of patients who require more intensive therapy and who may benefit from anti-PD-1 agents.

Clinical significance of soluble programmed cell death ligand-1 (sPD-L1) in hepatocellular carcinoma patients treated with radiotherapy

PurposeTo investigate the clinical implications of the soluble programmed cell death-ligand 1 (sPD-L1) level in hepatocellular carcinoma (HCC) patients treated with radiotherapy (RT). Materials/methodsHCC patients treated with RT between June 2011 and March 2015 were prospectively recruited and sPD-L1 levels were measured using an enzyme-linked immunosorbent assay. Blood samples were obtained at the RT start, RT end, and 1-month follow-up. The associations of the sPD-L1 level with the clinical features and outcomes were analyzed. ResultsFifty-three patients with HCC were included. Thirty-four patients received conventional fractionated RT with hepatic arterial infusional chemotherapy, while 19 patients received stereotactic body radiotherapy (SBRT). The initial sPD-L1 level was significantly associated with stage, tumor size, portal vein tumor thrombosis, and venous invasion. The overall-survival was significantly poorer in patients with a higher level of initial sPD-L1 (≥1.315 pg/mL). A higher level of sPD-L1 at 1 month (≥12.9 pg/mL) was significantly related to early lung metastasis. The sPD-L1 level was significantly increased after RT and the change pattern of sPD-L1 was different between two RT schemes. ConclusionsThe level of sPD-L1 was associated with tumor aggressiveness and outcomes, suggesting its role as a possible predictive biomarker. The increases in sPD-L1 after RT suggests that combined treatment with RT and immune checkpoint inhibitors may be a promising therapeutic strategy in HCC.

SPD-L1 Expression is Associated with Immunosuppression and Infectious Complications in Patients with Acute Pancreatitis.

Acute pancreatitis (AP) with infectious complications has high mortality because of early-stage immunosuppression. The programmed cell death-1 (PD-1)/programmed cell death ligand 1 (PD-L1) pathway is an important host immunosuppression mechanism. Soluble PD-L1 (sPD-L1) expression regulates co-inhibitory signals in malignancies or autoimmune disorders; however, its effects in AP are unknown. Here, we evaluated whether serum sPD-L1 is involved in immune dysfunction and assessed its relationship with infectious complications in early AP. Blood samples were obtained from 56 patients with acute pancreatitis and 21 healthy individuals in this prospective study. Serum sPD-L1 levels within 48h after AP onset were tested by enzyme-linked immunosorbent assays. Relevant immune parameters (human leucocyte antigen-DR, lymphocyte count) and inflammatory markers (C-reactive protein, white blood cell count) were analysed. sPD-L1 was significantly upregulated in patients with early AP, especially those with infectious complications, compared to healthy controls. Significant negative correlations were observed among monocyte HLA-DR expression, lymphocyte count and sPD-L1 levels in AP. Multivariate regression indicated that sPD-L1 was an independent risk factor for infectious complications in AP. The findings suggest that increased sPD-L1 expression appears to be involved in the development of immunosuppression in the early stage of AP and that sPD-L1 might be an early parameter for prediction of infectious complications in patients with AP.

Clinical Use of Programmed Cell Death-1 and Its Ligand Expression as Discriminatory and Predictive Markers in Ovarian Cancer.

Purpose: We aimed to establish whether programmed cell death-1 (PD-1) and programmed cell death ligand 1 (PD-L1) expression, in ovarian cancer tumor tissue and blood, could be used as biomarkers for discrimination of tumor histology and prognosis of ovarian cancer.Experimental Design: Immune cells were separated from blood, ascites, and tumor tissue obtained from women with suspected ovarian cancer and studied for the differential expression of possible immune biomarkers using flow cytometry. PD-L1 expression on tumor-associated inflammatory cells was assessed by immunohistochemistry and tissue microarray. Plasma soluble PD-L1 was measured using sandwich ELISA. The relationships among immune markers were explored using hierarchical cluster analyses.Results: Biomarkers from the discovery cohort that associated with PD-L1+ cells were found. PD-L1+ CD14+ cells and PD-L1+ CD11c+ cells in the monocyte gate showed a distinct expression pattern when comparing benign tumors and epithelial ovarian cancers (EOCs)-confirmed in the validation cohort. Receiver operating characteristic curves showed PD-L1+ and PD-L1+ CD14+ cells in the monocyte gate performed better than the well-established tumor marker CA-125 alone. Plasma soluble PD-L1 was elevated in patients with EOC compared with healthy women and patients with benign ovarian tumors. Low total PD-1+ expression on lymphocytes was associated with improved survival.Conclusions: Differential expression of immunological markers relating to the PD-1/PD-L1 pathway in blood can be used as potential diagnostic and prognostic markers in EOC. These data have implications for the development and trial of anti-PD-1/PD-L1 therapy in ovarian cancer. Clin Cancer Res; 23(13); 3453-60. ©2016 AACR.

Increase of Soluble Programmed Cell Death Ligand 1 in Patients with Chronic Hepatitis C.

Objectives: To determine whether the soluble programmed cell death ligand 1 (sPD-L1) levels in patients with chronic hepatitis C (CHC) are associated with the clinical features of the disease and the efficacy of treatment, including interferon (IFN)-α.Methods: We investigated the sPD-L1 levels in the sera of 80 genotype 1b Japanese patients with CHC who underwent 12 weeks of telaprevir (TVR)- or simeprevir (SMV)-based triple therapy followed by 12 weeks of dual therapy with pegylated IFN-α plus ribavirin. Serum was also obtained from 22 patients with chronic hepatitis B (CHB) and from 10 healthy donors (HC). The sPD-L1 levels were measured using an ELISA kit. In addition, we examined the PD-L1 expression on the cell surface of immortalized hepatocytes (HPT1) after incubation with cytokines, including IFN-γ.Results: The pretreatment serum sPD-L1 levels were significantly increased in patients with CHC (median 109.3 pg/ml, range 23.1-402.3) compared with patients with CHB (69.2 pg/ml, 15.5-144.8; P <0.001) and HC (100.3 pg/ml, 40.1-166.6; P = 0.039). No significant differences in the sustained virological response (SVR) rates were found between the TVR- (85.0%, n=40) and SMV-treated (80.0%, n=40) groups, and the pretreatment levels of serum sPD-L1 were not significantly different between patients who achieved SVR (105.0 pg/ml, 23.1-402.3) and non-SVR patients (133.5 pg/ml, 39.9-187.2; P = 0.391). The pretreatment level of sPD-L1 was positively correlated with the alanine aminotransferase and alpha-fetoprotein levels (R2 = 0.082, P = 0.016, and R2 = 0.149, P = 0.002, respectively). Although immortalized hepatocytes do not express PD-L1, we confirmed that PD-L1 expression was induced after stimulation with IFN-γ.Conclusions: In this study, we first found that sPD-L1 was increased in patients with CHC. Our results indicate that the level of serum sPD-L1 might be associated with the progression of CHC and the generation of hepatocellular carcinoma.

High plasma levels of soluble programmed cell death ligand 1 are prognostic for reduced survival in advanced lung cancer

ObjectivesProgrammed cell death-ligand 1 (PD-L1) expressed in tumor tissues is a key molecule for immune suppression, given its role in immune checkpoints. The significance and implication of soluble PD-L1 (sPD-L1) in the blood of lung cancer patients remain unknown. Patients and methodsBlood samples were prospectively collected from patients with advanced lung cancer, and the plasma sPD-L1 concentrations were measured by enzyme-linked immunosorbent assay. The correlations of the plasma sPD-L1 levels with clinico-pathological status, laboratory data, and survival of the patients were analyzed. ResultsNinety-six patients with advanced lung cancer were analyzed, including 73 with adenocarcinoma, 12 with squamous cell carcinoma, and seven with small-cell lung cancer. Sixty-five were naïve to chemotherapy, and 20 had received two or more lines of chemotherapy. The mean plasma sPD-L1 concentration of all the patients was 6.95±2.90ng/ml (range 2.30–20.0ng/ml), and this value is significantly increased compared with that previously reported for normal subjects. No correlation of the plasma sPD-L1 level with histological subtypes, adenocarcinoma genetic status, smoking history, clinical stage or laboratory data was found. However, overall survival was significantly reduced in patients with high (≥7.32ng/ml) compared with low (<7.32ng/ml) plasma sPD-L1 levels (13.0 vs. 20.4 months, p=0.037). Multivariate analysis revealed that high sPD-L1 levels were significantly related to poor prognosis (hazard ratio 1.99, p=0.041). ConclusionHigh plasma sPD-L1 levels were associated with poor prognosis in patients with advanced lung cancer, possibly associated with suppression of anti-tumor immunity.Clinical trial register and their clinical registration number: UMIN%000014760

Serum levels of soluble programmed cell death ligand 1 as a prognostic factor on the first-line treatment of metastatic or recurrent gastric cancer.

Immune checkpoint molecules are key targets for the treatment of various malignancies. Due to the heterogeneity of advanced gastric cancer (GC), the role of programmed cell death ligand 1 (PD-L1) expression as a tumor biomarker remains controversial. In this study, the prognostic value of soluble PD-L1 (sPD-L1) levels in serum samples was assessed in patients with metastatic GC. All patients received first-line treatment with fluoropyrimidine and platinum chemotherapy, and trastuzumab was added for HER2-positive patients. Serum levels of sPD-L1 were measured by enzyme-linked immunosorbent assay. Among 75 metastatic GC patients, the median serum sPD-L1 level was 0.704ng/ml (range <0.156-3.214). Serum sPD-L1 was significantly higher in patients with a high versus a low white blood cell count at baseline. When the cutoff value was set as the median, multivariate analyses showed that high sPD-L1 levels were associated with worse overall survival compared with low sPD-L1 levels (HR 2.218, 95% CI 1.139-4.320, P=0.019). Regardless of HER2 status, overall survival tended to be shorter in patients with high sPD-L1 compared with low sPD-L1. There was no significant association between sPD-L1 level and progression-free survival on the first-line treatment of metastatic GC. High serum levels of sPD-L1 correlated with worse overall survival on the first-line chemotherapy in metastatic GC patients.