Programmed Death-ligand 1 In Tissues Research Articles

Effect of PD-L1 and tumor regression rate on prognosis of nasopharyngeal carcinoma.

To explore the expression level of programmed death ligand-1 (PD-L1) and the tumor regression rate after chemoradiotherapy, and to investigate their influence on the prognosis of patients with nasopharyngeal carcinoma. Eighty-six patients, who were initially diagnosed with non-metastatic nasopharyngeal carcinoma in the Second Xiangya Hospital of Central South University from January 2014 to June 2014, were recruited. Positive expression of PD-L1 in prepared sections of nasopharyngeal carcinoma tissues was detected by immunohistochemical staining. The clinical data of recruited patients and the tumor regression rate were calculated before chemoradiotherapy and 1 month after chemoradiotherapy. In addition, the potential influence of PD-L1 level and the tumor regression rate after chemoradiotherapy on therapeutic efficacy and the prognosis of nasopharyngeal carcinoma were assessed. Among the 86 patients with nasopharyngeal carcinoma, there were 30 patients with high expression of PD-L1 in nasopharyngeal carcinoma sections (34.88%), while there were 56 patients with low expression (65.12%). Expression levels of PD-L1 in nasopharyngeal carcinoma tissues were not related with sex, age, smoking history, concurrent chemoradiotherapy, pathological type, N staging, tumor staging, and pre-treatment EBV-DNA load in peripheral blood in the affected patients (all P>0.05). But the expression level of PD-L1 was related to the tumor regression rate and T staging in the patients with nasopharyngeal carcinoma (both P<0.05). The expression levels of PD-L1 in nasopharyngeal carcinoma tissues was a risk factor for tumor regression rate (OR=0.226, P<0.05). Compared with the patients with low expression levels of PD-L1, there was shorter disease-free survival in the patients with high expression levels of PD-L1 (P<0.05). Moreover, compared with the patients with low tumor regression rate, the nasopharyngeal carcinoma patients with high tumor regression rate showed a favorable disease-free survival (P<0.05). A high expression level of PD-L1 and a low tumor regression rate after chemoradiotherapy are unfavorable to the prognosis of nasopharyngeal carcinoma.

Histone deacetylase 6 inhibition in urothelial cancer as a potential new strategy for cancer treatment.

Histone deacetylases (HDACs) are enzymes that remove acetyl groups from histones and have attracted attention as potential targets for cancer therapy. Several small molecule inhibitors have been developed to target HDACs; however, clinical trials of pan-HDAC inhibitors have found these types of inhibitors to be inefficient and to be relatively highly toxic. In the present study, the role of one HDAC isozyme, HDAC6, in urothelial cancer was investigated. Protein expression levels and subcellular localization of HDAC6 was identified in surgically resected bladder tumors using immunohistochemistry. The antitumor effects of 12 small molecule HDAC6 inhibitors were also examined in vitro using cultured urothelial cancer cells. The HDAC6 inhibitors decreased cell viability, with IC50 values in the low µM range, as low as 2.20 µM. HDACi D, E and F had the lowest IC50 values. HDAC6 has been previously reported to regulate programmed death-ligand 1 (PD-L1) and PD-L1 expression was found to be a predictor of decreased overall survival time. There was no association between the protein expression level of HDAC6 and PD-L1 in tumor tissues; however, HDAC6 inhibition by specific small molecule inhibitors resulted in decreased expression levels of membranous PD-L1 in cultured urothelial cancer cell lines. The results suggested that inhibition of HDAC6 could be a promising novel approach for the treatment of urothelial cancer.

Immunoaffinity microflow liquid chromatography/tandem mass spectrometry for the quantitation of PD1 and PD-L1 in human tumor tissues.

High tumor expression of programmed cell death protein (PD1) and programmed death-ligand 1 (PD-L1) is thought to be associated with positive clinical outcomes after treatment with anti-PD1 or anti-PD-L1 agents. Several sensitive methods based on immunohistochemistry, ligand binding assay (LBA), and liquid chromatography/mass spectrometry involving the measurement of PD1 and PD-L1 expression have been reported. Here, we expand on the characterization of different tumor types using a highly specific, sensitive, and robust immunoaffinity liquid chromatography/tandem mass spectrometry (IA-LC/MS/MS)-based method for the simultaneous quantitation of PD1 and PD-L1 in tumor tissues. Human tumor tissue samples were homogenized using a Precellys Evolution homogenizer. The samples were incubated with anti-PD1 and anti-PD-L1 capture polyclonal antibodies, which were bound to magnetic beads. Following enrichment, samples were digested with trypsin. A Waters iKEY HSS T3 1.8 um (150 μm × 100 mm) column with a gradient flow rate of 3 μL/min was used for chromatographic separation, and a Waters TQ-S triple quadrupole mass spectrometer was used for detection. Selected reaction monitoring (SRM) transitions with unit resolution for precursor/product ion masses were optimized for PD1 and PD-L1 surrogate peptides. The surrogate peptides LAAFPEDR for PD1 and FTVTVPK for PD-L1 yielded the most intense SRM transitions at m/z 459.7 > 516.2 and m/z 396.2 > 543.3, respectively, and thus were selected for the quantitation of PD1 and PD-L1. The lower limit of quantitation for PD1 and PD-L1 was 0.062 ng/mL with an assay range up to 10 ng/mL. Using this method, human PD1 and PD-L1 were detected and quantified from four different types of tumor tissues. The data show that PD1 expression level was highly correlated with that of PD-L1 in all tumor tissues analyzed here. A highly specific and sensitive immunoaffinity microflow LC/MS/MS method for the simultaneous quantification of PD1 and PD-L1 in tumor tissues was developed and implemented. This method combines the advantage of immuno-capture for analyte enrichment with the high specificity of detection of multiple surrogate peptides by LC/MS/MS. The quantification of PD1 and PD-L1 co-expression in tumor could help evaluate their role in assessing tumor type selection and patient stratification.

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.

Prognosis significance of indoleamine 2, 3-dioxygenase, programmed death ligand-1 and tumor-infiltrating immune cells in microenvironment of breast cancer

IntroductionThe immune microenvironment plays an increasingly important role in predicting the prognosis of multiple tumors and selecting patients for immunotherapy trials. We studied the expression of indoleamine 2, 3-dioxygenase (IDO) and programmed death ligand-1 (PD-L1), detected the proportion of tumor-infiltrating immune cells (TIIs), and further analyzed the association of these immunological characteristics with the clinicopathological parameters and prognosis of breast cancer patients. MethodsImmunohistochemical staining for IDO, PD-L1, CD4, CD8, Foxp3, CD20, CD56 and CD68 expression in breast cancer tissues was carried out. IDO and PD-L1 expression were scored by extent in tumor cells. TIIs expressing CD4, CD8, Foxp3, CD20, CD56 or CD68 were evaluated by positive count. Clinicopathological characteristics and follow-up were recorded. ResultsThe frequencies of IDO-high-expressing and PD-L1-expressing tissue were 33.77% and 24.68%, respectively. The co-expression of IDO and PD-L1 was identified in 16/77 (20.78%) of cases. IDO high expression, CD4+ T cells and CD56+ cells were most frequently observed in patients with tumor-draining lymph nodes(TDLNs) metastasis. Immune cells were more common in non-luminal breast cancer than in luminal breast cancer. In survival analysis, PFS were not associated with high levels of IDO and PD-L1, nor were TIIs. However, CD20 and CD68 were significant risk factors for prognostic after adjusting covariates by COX regression. IDOhighFoxp3highT patients had a tendency with shorter progression-free survival. ConclusionsAlthough we found a limited prognostic effect of TIIs on survival in breast cancer patients, IDO combined with TIIs can help to evaluate the prognosis of patients.

Relationship between IL-10 and PD-L1 in esophageal carcinoma tissues and IL-10 down-regulates PD-L1 expression via Met signaling pathway.

Programmed death-ligand 1 (PD-L1) plays a critical role in host immunity in the setting of cancer progression. Interleukin 10 (IL-10) is a multi-cellular, multi-functional cytokine that regulates cell growth and differentiation and participates in inflammatory and immune responses. The purpose of this study was to clarify the relationship between PD-L1 and IL-10 and their clinical importance in esophageal carcinoma (ESCA). ESCA patients (n=100) who underwent surgery with preoperative therapy were included in the study. By immuno-histochemical staining, PD-L1, IL-10 and CD8 positive cells were examined in resected specimens. The gene expression levels of PD-L1, IL-10 and Met were detected by qRT-PCR and Western blots, and differentially compared in cancer, adjacent and normal tissues. In cell experiments, the Eca109 and TE-1 cell-lines were incubated with IL-10 or anti-IL-10 antibody, and then PD-L1 and Met expression levels were compared by ELISA and Western blots. The effect of crizotinib and/or IL-10 on the proliferation, invasion and migration of esophageal squamous cell-lines was estimated by CCK8 and transwell assay. In tumor tissues, the mRNA and protein levels of PD-L1, IL-10 and Met were higher than those in adjacent tissues. The high expression levels of PD-L1 and IL-10 indicated a poor prognosis. IL-10 reduced the expression of PD-L1 in esophageal squamous cell-lines via Met signaling. Over-expression of PD-L1 in increased the levels of IL-10, and Met in in ESCA tissue and cell lines. The combination of crizotinib and IL-10 were more effective in inhibiting the proliferation, migration and invasion of esophageal squamous cell lines. The combination of IL-10 and PD-L1 monoclonal antibody may have therapeutic promise in treating ESCA.

PDL1-targeted vaccine exhibits potent antitumor activity by simultaneously blocking PD1/PDL1 pathway and activating PDL1-specific immune responses.

Despite the clinical success of immune checkpoint blockade, only a subset of people exhibits durable responses, suggesting that an alternative immunotherapeutic strategy is required. This paper reported a two-in-one cancer vaccine that targets programmed death ligand 1 (PDL1) that blocks the PD1/PDL1 pathway and also activates antitumor immune response. The PDL1- NitraTh vaccine, which consists of the extracellular domain of PDL1 and nitrated T cell epitope, effectively broke the immune tolerance of PDL1 and elicited PDL1-specific humoral and cellular immunity. The treatment of PDL1-NitraTh exhibited potent antitumor activity. Moreover, immunization of PDL1 vaccine increased the infiltration of tumor lymphocytes and decreased the proportion of Treg cells in tumor tissues, suggesting that the vaccine may remodel the tumor microenvironment. The upregulation of PDL1 in tumor tissues was induced by PDL1-NitraTh vaccine but not in spleen and lymphomas. This upregulation of PDL1 is beneficial to the antitumor activity of PDL1-specific humoral and cellular immunity induced by PDL1-NitraTh. In summary, PDL1-targeted vaccine exhibits potent antitumor activity and may provide an alternative immunotherapy strategy for patients who are not sensitive to PDL1 antibody drugs.

P103 The treatment effect of tonsil-derived mesenchymal stem cells (T-MSCs) via regulating programmed death-1/programmed death ligand-1 (PD-1/PD-L1) in ulcerative colitis

Abstract Background The programmed death 1 (PD-1)/programmed death-ligand 1 (PD-L1) pathway has not been fully evaluated in inflammatory bowel disease. We evaluated the level of PD-1/PD-L1 in the mucosa of patients with ulcerative colitis and revealed the role of PD-1/PD-L1 in the immunomodulatory mechanism of tonsil-derived mesenchymal stem cells (T-MSCs). Methods We used chronic murine colitis model induced by dextran sodium sulphate (DSS). We measured the PD-1 and PD-L1 levels in inflamed colonic tissues before and after the treatment with T-MSC. We also measured the levels of PD-1 and PD-L1 in the colonic tissues from patients with ulcerative colitis and compared with those from normal controls. Results In chronic colitis model, the level of PD-L1 was decreased than normal controls (fold change) (1.0 vs. 0.46 ± 0.08, p = 0.05). However, the level of PD-1 was increased than normal controls (1.0 vs. 6.84 ± 8.16, p = 0.142). After treatment with T-MSC which showed significant improvement in body weight, disease activity index and colon length, the levels of PD-1 and PD-L1 were recovered; PD-L1 was significantly increased (1.04 ± 0.77 vs. 0.46 ± 0.08, p = 0.031) and the level of PD-1 was decreased (3.63 ± 1.94 vs. 6.84 ± 8.16, p = 0.537). When measuring the level of PD-1 and PD-L1 in both soluble medium and cell lysate of T-MSC, we found that the PD-1 and PD-L1 were expressed in both forms (182.63 pg/ml in soluble medium and 11.85 pg/protein (μg) in cell lysate after 7 days of differentiation period). In the analysis using human colonic tissues, a significantly increase in the levels of PD-1 and PD-L1 was observed in the colonic mucosa of patients with UC compared with normal controls (PD-1: 2.09 ± 3.95 vs. 7.93 ± 14.21, p = 0.034 and PD-L1: 2.24 ± 2.91 vs. 10.08 ± 18.13, p = 0.044). Conclusion The altered expression of PD-1 and PD-L1 in colonic mucosa may a possible mechanism of ulcerative colitis and T-MSC-derived PD-L1 could repress the colitis.

Serum PD-1 Levels Change with Immunotherapy Response but Do Not Predict Prognosis in Patients with Hepatocellular Carcinoma

Background/Aims: Programmed death receptor 1 (PD-1) is a promising new target for treatment of patients with hepatocellular carcinoma (HCC). A high expression level of programmed death-ligand 1 (PD-L1) is a possible prognostic indicator for poor outcome in other malignancies. Here, we investigated the clinical significance of PD-1 and PD-L1 in patients with HCC. Methods: We enrolled patients with HCC who underwent surgical resection at Severance Hospital between 2012 and 2017 and investigated the levels of PD-L1 in HCC tissues (tPD-L1) and PD-L1/PD-1 in serum (sPD-L1/sPD-1). We also aimed to determine whether expression levels correlated with clinical and histological features. Results: A total of 72 patient samples were analyzed. The median sPD-L1 and sPD-1 levels were 25.72 and 341.44 pg/mL, respectively. A positive correlation was detected between tPD-L1 and sPD-1 levels (R2=0.426, P 50% reduction in sPD-1 levels was observed immediately after nivolumab administration. However, sPD-1 level was not associated directly with prognosis in patients with advanced HCC. Conclusions: The results demonstrated that PD-L1 and PD-1 levels changed according to the immunotherapy. However, no significant association with clinical outcome in patients with HCC was detected. (J Liver Cancer 2019;19:108-116)

Expression of programmed death ligand 1 in liver cancer and its clinical significance

Objective To investigate the expression of programmed death ligand 1 (PD-L1) in liver cancer tissues and its clinical significance. Methods The expression levels of PD-L1 in 110 liver cancer tissues, including 95 cases of hepatocellular carcinoma and 15 cases of cholangiocarcinoma were detected by using immunohistochemical staining method, and the relationship between PD-L1 expression and the clinicopathological characteristics of patients with hepatocellular carcinoma was analyzed. Results Immunohistochemistry results showed that the positive rate of PD-L1 in liver cancer tissues was 69.1% (76/110), and the positive rate of membrane and cytoplasm was 46.4% (51/110) and 22.7% (25/110), respectively. The positive rate of PD-L1 expression in hepatocellular carcinoma was higher than that in cholangiocarcinoma [78.9% (75/95) vs. 6.7% (1/15)], and the difference was statistically significant (χ 2 = 31.693, P 0.05). Further analysis showed that protein expression localization of PD-L1 was closely related to the pathological grade in hepatocellular carcinoma (P = 0.013). Conclusion The positive expression of PD-L1 in hepatocellular carcinoma is closely associated with depth of invasion and TNM stage, which provides a theoretical basis for the immunotherapy of liver cancer targeting PD-L1. Key words: Liver neoplasms; Programmed death ligand 1; Immunohistochemistry

Progress in the expressions of programmed death 1 and programmed death ligand 1 in lung cancer

In tumor immunotherapy, the study of programmed death 1 (PD-1) and programmed death ligand 1 (PD-L1) provides a new approach for the comprehensive treatment of advanced lung cancer. About 20% of patients with non-small cell lung cancer could benefit from lung cancer immunotherapy, while those with high PD-L1 expression will benefit more. At present, there are few related studies on PD-1 expression at home and abroad, and the detection of PD-1/PD-L1 expressions is mostly concentrated in tumor tissues. With the research progress of liquid biopsy technology, the convenience and accuracy of peripheral blood testing are also receiving more and more attention. However, there are still few biological indicators for predicting the efficacy of tumor immunotherapy, and the uniform standard and accuracy of testing still need more clinical practice and exploration. This article reviews the research on the expressions of PD-1 and PD-L1 in tissues and peripheral blood of patients with lung cancer, aiming to provide reference for the treatment of lung cancer with immune checkpoint blockers. Key words: Lung neoplasms; Immunotherapy; Programmed death 1; Programmed death ligand 1

In vitro assessment of PD-L1+ microvesicles in the cyst fluid of non-syndromic odontogenic keratocysts

Odontogenic keratocysts (OKCs) are jaw cystic lesions which are characterized by local invasion and high recurrence rate. The majority of OKCs are exposed to microorganisms and occur along with focal inflammatory infiltrates. Cyst fluids are biological fluids that contain a large content of cytokines and immune globulins. Inhibitory receptor such as programmed death receptor 1 (PD-1) and its ligand programmed death-ligand 1 (PD-L1), which can induce a coinhibitory signal in activated T cells, plays a vital role in the differentiation, exhaustion and apoptosis of T cells. Cell derived microvesicles, carrying a cargo of functional proteins, nucleic acids and lipids, are important communication tools in the development of diseases. However, the expression of PD-L1 in OKCs tissues and whether PD-L1 could be carried by microvesicles are unexplored. Presently, we have isolated cyst fluid microvesicles and identified cell derived PD-L1+ cyst fluid microvesicles. PD-L1 was located in the membrane of the cyst fluid microvesicles. The main cellular origins of PD-L1+ cyst fluid microvesicles were dendritic cells followed by lymphocytes. Elevated PD-L1+ cyst fluid microvesicles were detected in the OKCs compared with dentigerous cysts. Isolated cyst fluid microvesicles could bind to the membrane of activated CD8 T cells and inhibit proliferation of stimulated peripheral blood CD8 T cells. In conclusion, the present study suggests that elevated PD-L1+ cyst fluid microvesicles might be related with the cyst development of OKCs.

PC-1 Genetic and pharmaceutical inactivation of hypoxia-inducible factor 1α reveals a molecular switch from graft vs host diseases to graft vs leukemia effect

PC-1 Genetic and pharmaceutical inactivation of hypoxia-inducible factor 1α reveals a molecular switch from graft vs host diseases to graft vs leukemia effect

Expression and prognostic value of PD-L1 and PD-L2 in ovarian cancer.

BackgroundIn the present study, we aimed to investigate the expression and prognostic value of co-stimulatory molecules, programmed death ligand-1 (PD-L1) and PD-L2, in ovarian cancer (OC).MethodsImmunohistochemical (IHC) staining was used to assess the expressions of PD-L1 and PD-L2 in 77 cases of OC, and 10 cases of benign ovarian cyst were employed as negative controls. Moreover, χ2 test was used to analyze the correlation between the PD-L1/PD-L2 expression and clinicopathological parameters. Kaplan-Meier method was used to compare the effects of PD-L1/PD-L2 expression level on the overall survival (OS) of OC patients.ResultsPD-L1 and PD-L2 were mainly expressed on membrane and in cytoplasm of OC cells. The high-expression rate of PD-L1 and PD-L2 in OC tissues was 44.16% (34/77) and 22.08% (17/77), respectively. The expression of PD-L1 in OC cells was significantly correlated with FIGO stage (P=0.026), while its expression was not significantly correlated with other clinicopathological parameters. There was no significant correlation between PD-L2 and any clinicopathological parameters. Kaplan-Meier survival analysis showed that the OS of high PD-L1 expression group was significantly shorter compared with the low PD-L1 expression group (HR =2.689, 95% CI: 1.400–5.163). Patients with high PD-L2 expression also exhibited significantly shorter OS (HR =2.204, 95% CI: 1.037–4.682). Multivariable analysis displayed that high expression of PD-L1 (HR =2.275, 95% CI: 1.120–4.169), high expression of PD-L2 (HR =2.314, 95% CI: 1.136–4.714) and FIGO stage (HR =11.229, 95% CI: 1.373–91.865) were independent prognostic factors of OC. When negative expressions of both PD-L1 and PD-L2 were used as a combined prognostic factor, the OS was significantly prolonged (HR =3.396, 95% CI: 1.858–6.029). According to our previous studies, patients with negative PD-L1 expression and high T-bet+ TIL infiltration have higher OS than other patients. Patients with positive PD-L1 expression and low T-bet+ TIL infiltration exhibit the shortest OS. Collectively, our findings provided the basis for PD-1/PD-L1 or PD-1/PD-L2 blockade therapy for OC patients.ConclusionsCo-stimulatory molecules, PD-L1 and PD-L2, were highly expressed in OC tissues, and their expression levels were correlated with FIGO stage, age and prognosis. These results suggested that PD-L1 and PD-L2 were involved in the occurrence and development of malignant OC, indicating their potential value in clinical diagnosis and prognosis of OC.

Expression and prognostic value of PD-L1 and PD-L2 in ovarian cancer

Background: In the present study, we aimed to investigate the expression and prognostic value of co-stimulatory molecules, programmed death ligand-1 (PD-L1) and PD-L2, in ovarian cancer (OC). Methods: Immunohistochemical (IHC) staining was used to assess the expressions of PD-L1 and PD-L2 in 77 cases of OC, and 10 cases of benign ovarian cyst were employed as negative controls. Moreover, χ 2 test was used to analyze the correlation between the PD-L1/PD-L2 expression and clinicopathological parameters. Kaplan-Meier method was used to compare the effects of PD-L1/PD-L2 expression level on the overall survival (OS) of OC patients. Results: PD-L1 and PD-L2 were mainly expressed on membrane and in cytoplasm of OC cells. The high-expression rate of PD-L1 and PD-L2 in OC tissues was 44.16% (34/77) and 22.08% (17/77), respectively. The expression of PD-L1 in OC cells was significantly correlated with FIGO stage (P=0.026), while its expression was not significantly correlated with other clinicopathological parameters. There was no significant correlation between PD-L2 and any clinicopathological parameters. Kaplan-Meier survival analysis showed that the OS of high PD-L1 expression group was significantly shorter compared with the low PD-L1 expression group (HR =2.689, 95% CI: 1.400–5.163). Patients with high PD-L2 expression also exhibited significantly shorter OS (HR =2.204, 95% CI: 1.037–4.682). Multivariable analysis displayed that high expression of PD-L1 (HR =2.275, 95% CI: 1.120–4.169), high expression of PD-L2 (HR =2.314, 95% CI: 1.136–4.714) and FIGO stage (HR =11.229, 95% CI: 1.373–91.865) were independent prognostic factors of OC. When negative expressions of both PD-L1 and PD-L2 were used as a combined prognostic factor, the OS was significantly prolonged (HR =3.396, 95% CI: 1.858–6.029). According to our previous studies, patients with negative PD-L1 expression and high T-bet + TIL infiltration have higher OS than other patients. Patients with positive PD-L1 expression and low T-bet + TIL infiltration exhibit the shortest OS. Collectively, our findings provided the basis for PD-1/PD-L1 or PD-1/PD-L2 blockade therapy for OC patients. Conclusions: Co-stimulatory molecules, PD-L1 and PD-L2, were highly expressed in OC tissues, and their expression levels were correlated with FIGO stage, age and prognosis. These results suggested that PD-L1 and PD-L2 were involved in the occurrence and development of malignant OC, indicating their potential value in clinical diagnosis and prognosis of OC.

LncRNA MALAT1 contributes to non-small cell lung cancer progression via modulating miR-200a-3p/programmed death-ligand 1 axis.

This study was to investigate the expression correlation between long non-coding RNA metastasis-associated lung adenocarcinoma transcript 1 (lncRNA MALAT1), miR-200a-3p and programmed death-ligand 1 (PD-L1) in non-small cell lung cancer (NSCLC), and their roles in NSCLC. Real-time polymerase chain reaction (PCR) was performed to detect the expressions of MALAT1, miR-200a-3p and PD-L1 in NSCLC tissues and cells for the correlation analysis. The starBase and Targetscan databases were used to predict the binding sites between MALAT1 and miR-200a-3p, and miR-200a-3p and PD-L1, respectively. The targeting relationship between MALAT1 and miR-200a-3p, and miR-200a-3p and PD-L1 were further verified by real-time PCR and dual luciferase reporter gene assay. Cell proliferation was monitored by CCK8 and colony formation assays. The apoptosis was detected using flow cytometry. Wound healing assay and transwell assay were conducted to determine cell migration and invasion. In this study, we demonstrated that in NSCLC tissues, the expression level of MALAT1 was negatively correlated with that of miR-200a-3p, while positively correlated with PD-L1. Besides, MALAT1 promoted proliferation, mobility, migration, and invasion of NSCLC cells via sponging miR-200a-3p. PD-L1 was validated as a target of miR-200a-3p, and indirectly modulated by MALAT1. In conclusion, LncRNA MALAT1 facilitates the progression of NSCLC by modulating miR-200a-3p/PDL1 axis.

Expression of Programmed Death-Ligand 1 in Laryngeal Carcinoma and its Effects on Immune Cell Subgroup Infiltration.

To study the expression of programmed death-ligand 1 (PD-L1), and its effects on CD8+ tumor infiltrating lymphocytes (TILs) and tumor associated macrophages (TAMs) in human laryngeal squamous cell carcinoma. Sixty-nine patients with laryngeal carcinoma and 10 with vocal cord leukoplakia received tumor resection at Neck Surgery Department in the Second Affiliation Hospital of Jilin University (Changchun, Jilin) from Jan. 2010 to Dec. 2015. The expressions of PD-L1, CD8, CD16 and CD206 in laryngeal carcinoma, paracancerous and vocal cord leukoplakia tissues were detected with immunohistochemistry. The associations between PD-L1 expression and clinicopathologic features, expression of TAMs and CD8+ T cell infiltration were analyzed. Expression of PD-L1 is significantly higher in laryngeal carcinoma than in paracancerous or leukoplakia tissue. The expression of PD-L1 is closely associated with stage of laryngeal cancer, histological differentiation and neck lymphatic metastasis. PD-L1 expression is negatively correlated with the number of CD8+ TILs and CD16+ cells (M1 type TAMs), while is positively associated with CD206+ (M2 type TAMs). PD-L1 is highly expressed in the laryngeal cancer with the tumor microenvironment immunosuppression.

Multiplex Immuno-Liquid Chromatography–Mass Spectrometry–Parallel Reaction Monitoring (LC–MS–PRM) Quantitation of CD8A, CD4, LAG3, PD1, PD-L1, and PD-L2 in Frozen Human Tissues

The immune status of tumors critically influences their responsiveness to PD1 blockades and other immune-based therapies. Programmed death ligand 1 (PD-L1) immunohistochemistry (IHC) is a clinically validated predictive biomarker of response to checkpoint-inhibitor therapy in a limited number of clinical settings but is poorly predictive in most. With emerging evidence that multiple pathways and immune-checkpoint proteins may coordinately contribute to the adaptive immune resistance, the identification and quantitation of multiple immune markers in tumor tissue could help identify the controlling pathways in a given patient, guide the selection of optimal therapy, and monitor response to treatment. We developed and validated a sensitive and robust immuno-liquid chromatography-parallel reaction monitoring assay to simultaneously quantify the expression levels of six immune markers (CD8A, CD4, LAG3, PD1, PD-L1, and PD-L2) using as little as 1-2 mg of fresh frozen tissue. The lower limit of quantitation ranged from 0.07 ng/mg protein for PD1 to 1.0 ng/mg protein for CD4. The intrabatch accuracy was within -16.6% to 15.0% for all proteins at all concentrations, and the variation ranged from 0.8% to 14.7%, while interbatch accuracy was within -6.3% to 8.6%, and the variation ranged from 1.3% to 12.8%. The validated assay was then applied to quantify all six biomarkers in different tissues and was confirmed to have sufficient sensitivity (0.07-1.00 ng/mg protein) and reproducibility (variation ranged from 4.3 to 12.0%). In an analysis of 26 cervical tumors, CD8A and CD4 were detected in all tumors, followed by PD-L1 in 85%, LAG-3 in 65%, PD1 in 50%, and PD-L2 in 35%. The strongest correlations were observed between CD8A and CD4 ( r = 0.88) and CD8A and LAG-3 ( r = 0.86). PD1 was not significantly correlated with any of the other proteins tested. This method can be applied to survey the immune signatures across tumor types and tailored to incorporate additional markers as needed.

Fading With Time of PD-L1 Immunoreactivity in Non–Small Cells Lung Cancer Tissues: A Methodological Study

Blockade of inhibitory immune checkpoints is currently arising as a potential immunologic option for tumor therapy. Inhibition of programmed cell death protein 1 and/or its specific ligand programmed death-ligand 1 (PD-L1) was effective in clinical trials in advanced melanoma, non-small cell lung cancer (NSCLC) bladder and kidney cancer. The predictive role of the immunohistochemical (IHC) expression of PD-L1 is highly debated. Different reagents, clones, cutoffs of cell expression and subjective interpretation of PD-L1 immunoreactivity in epithelial cells and lymphocytes are the main issue. In this study we selected 58 consecutive NSCLC surgical specimens that underwent pathologic examination from January 2014 to July 2015. Using a tissue microarray approach we evaluated the IHC expression of PD-L1 in tumor-infiltrating lymphocytes and tumor cells (TCs) and compared the ICH staining with tumor histology, grade and the age of the tissue blocks. The main new finding was the fading of PD-L1 IHC expression in TCs in tissues processed in 2014 compared with 2015. PD-L1 expression in tumor-infiltrating lymphocytes in the 2 years was similar. We also found a significant higher immunoreactivity of TCs in high grade NSCLC and in the squamous carcinoma histotype compared with low grade tumors and the adenocarcinoma histology (P=0.013). We demonstrated that the IHC evaluation of PD-L1 in NSCLC archival tissues is feasible and can be implemented in a routine pathology setting, but it should be carefully assessed in tissue blocks older than 1 year.

PD-L1 Expression Correlates With Tumor Infiltrating Lymphocytes And Response To Neoadjuvant Chemotherapy In Cervical Cancer.

Programmed death-ligand 1 (PD-L1) has been reported to be expressed in many types of tumor cells, and bind to PD-1 on T lymphocytes to inhibit immune response. Immunologic checkpoint blockade with antibodies that target the PD1/PD-L1 pathway has demonstrated to have impressive antitumor effects on many malignancies. However, the significance of PD1/PD-L1 pathway in cervical cancer remains unclear. Here we studied PD-L1, PD-1, CD8 and HPV expression in cervical cancer and normal cervix by immunohistochemical staining. Our results showed that there was more frequently positive for PD-L1, PD-1 and CD8 in cervical cancer tissues compared to normal tissues, especially those strongly stained HPV. Additionally, PD-L1, PD-1 and CD8 were more frequently stained in tissues from advanced tumor and tumor with lymphoid nodes or vascular invasion respectively. Tissues from patients with chemotherapy history had over expression of PD-L1 in tumor cells and more PD-1 and CD8 in stromal mononuclear cells, which were identified as tumor infiltrated lymphocytes (TILs). These findings point to a key role of PD-L1 in immune escape of cervical cancer, and provide a rationale for therapeutic targeting of the PD-1/PD-L1 pathway.