Assessment of programmed death-ligand 1 expression in primary tumors and paired lymph node metastases of gastric adenocarcinoma

BACKGROUND Anti-programmed death-1/programmed death-ligand 1(PD-1/PD-L1)immuno-therapy has demonstrated promising results on gastric cancer(GC).However,PD-L1 can express differently between metastatic sites and primary tumors(PT).AIM To compare PD-L1 status in PT and matched lymph node metastases(LNM)of GC patients and to determine the correlation between the PD-L1 status and clinicopathological characteristics.METHODS We retrospectively reviewed 284 GC patients who underwent D2-gastrectomy.PD-L1 was evaluated by immunohistochemistry(clone SP142)using the com-bined positive score.All PD-L1+PT staged as pN+were also tested for PD-L1 expression in their LNM.PD-L1(-)GC with pN+served as the comparison group.RESULTS Among 284 GC patients included,45 had PD-L1+PT and 24 of them had pN+.For comparison,44 PD-L1(-)cases with pN+were included(sample loss of 4 cases).Of the PD-L1+PT,54.2%(13/24 cases)were also PD-L1+in the LNM.Regarding PD-L1(-)PT,9.1%(4/44)had PD-L1+in the LNM.The agreement between PT and LNM had a kappa value of 0.483.Larger tumor size and moderate/severe peritumoral inflammatory response were associated with PD-L1 positivity in both sites.There was no statistical difference in overall survival for PT and LNM according to the PD-L1 status(P=0.166 and P=0.837,respectively).CONCLUSION Intra-patient heterogeneity in PD-L1 expression was observed between the PT and matched LNM.This disagreement in PD-L1 status may emphasize the importance of considering different tumor sites for analyses to select patients for immunotherapy.

Efficacy of chemotherapy containing bevacizumab in patients with metastatic colorectal cancer according to programmed cell death ligand 1

BACKGROUND Bevacizumab,an anti-vascular endothelial growth factor(VEGF)monoclonal antibody,inhibits angiogenesis and reduces tumor growth.Serum VEGF-C,lactate dehydrogenase,and inflammatory markers have been reported as predictive markers related to bevacizumab treatment.Programmed cell death ligand 1(PD-L1)could act upon VEGF receptor 2 to induce cancer cell angiogenesis and metastasis.AIM To investigate the efficacy of bevacizumab-containing chemotherapy in patients with metastatic colorectal cancer(CRC)according to the expression of PD-L1.METHODS This analysis included CRC patients who received bevacizumab plus FOLFOX or FOLFIRI as first-line therapy between June 24,2014 and February 28,2022,at Samsung Medical Center(Seoul,South Korea).Analysis of patient data included evaluation of PD-L1 expression by the combined positive score(CPS).We analyzed the efficacy of bevacizumab according to PD-L1 expression status in patients with CRC.RESULTS A total of 124 patients was included in this analysis.Almost all patients were treated with bevacizumab plus FOLFIRI or FOLFOX as the first-line chemotherapy.While 77%of patients received FOLFOX,23%received FOLFIRI as backbone first-line chemotherapy.The numbers of patients with a PD-L1 CPS of 1 or more,5 or more,or 10 or more were 105(85%),64(52%),and 32(26%),respectively.The results showed no significant difference in progression-free survival(PFS)and overall survival(OS)with bevacizumab treatment between patients with PDL1 CPS less than 1 and those with PD-L1 CPS of 1 or more(PD-L1<1%vs PD-L1≥1%;PFS:P=0.93,OS:P=0.33),between patients with PD-L1 CPS less than 5 and of 5 or more(PD-L1<5%vs PD-L1≥5%;PFS:P=0.409,OS:P=0.746),and between patients with PD-L1 CPS less than 10 and of 10 or more(PD-L1<10%vs PD-L1≥10%;PFS:P=0.529,OS:P=0.568).CONCLUSION Chemotherapy containing bevacizumab can be considered as first-line therapy in metastatic CRC irrespective of PD-L1 expression.

Blocking postsynaptic density-93 binding to C-X3-C motif chemokine ligand 1 promotes microglial phenotypic transformation during acute ischemic stroke

We previously reported that postsynaptic density-93 mediates neuron-microglia crosstalk by interacting with amino acids 357–395 of C-X3-C motif chemokine ligand 1(CX3 CL1) to induce microglia polarization. More importantly, the peptide Tat-CX3 CL1(comprising amino acids 357–395 of CX3 CL1) disrupts the interaction between postsynaptic density-93 and CX3 CL1, reducing neurological impairment and exerting a protective effect in the context of acute ischemic stroke. However, the mechanism underlying these effects remains unclear. In the current study, we found that the pro-inflammatory M1 phenotype increased and the anti-inflammatory M2 phenotype decreased at different time points. The M1 phenotype increased at 6 hours after stroke and peaked at 24 hours after perfusion, whereas the M2 phenotype decreased at 6 and 24 hours following reperfusion. We found that the peptide Tat-CX3 CL1(357–395 aa) facilitates microglial polarization from M1 to M2 by reducing the production of soluble CX3 CL1. Furthermore, the a disintegrin and metalloprotease domain 17(ADAM17) inhibitor GW280264 x, which inhibits metalloprotease activity and prevents CX3 CL1 from being sheared into its soluble form, facilitated microglial polarization from M1 to M2 by inhibiting soluble CX3 CL1 formation. Additionally, Tat-CX3 CL1(357–395 aa) attenuated long-term cognitive deficits and improved white matter integrity as determined by the Morris water maze test at 31–34 days following surgery and immunofluorescence staining at 35 days after stroke, respectively. In conclusion, Tat-CX3 CL1(357–395 aa) facilitates functional recovery after ischemic stroke by promoting microglial polarization from M1 to M2. Therefore, the Tat-CX3 CL1(357–395 aa) is a potential therapeutic agent for ischemic stroke.

Programmed death 1, ligand 1 and 2 correlated genes and their association with mutation, immune infiltration and clinical outcomes of hepatocellular carcinoma

BACKGROUND The exact regulation network of programmed death 1(PD-1), programmed death ligand 1(PD-L1), and programmed death ligand 2(PD-L2) signaling in immune escape is largely unknown. We aimed to describe the gene expression profiles related to PD-1 as well as its ligands PD-L1 and PD-L2, thus deciphering their possible biological processes in hepatocellular carcinoma(HCC).AIM To find the possible mechanism of function of PD-1, PD-L1, and PD-L2 in HCC.METHODS Based on the expression data of HCC from The Cancer Genome Atlas, the PD-1/PD-L1/PD-L2 related genes were screened by weighted correlation network analysis method and the biological processes of certain genes were enriched. Relation of PD1/PD-L1/PD-L2 with immune infiltration and checkpoints was investigated by co-expression analysis. The roles of PD-1/PD-L1/PD-L2 in determination of clinical outcome were also analyzed.RESULTS Mutations of calcium voltage-gated channel subunit alpha1 E, catenin beta 1, ryanodine receptor 2, tumor suppressor protein p53, and Titin altered PD-1/PDL1/PD-L2 expression profiles in HCC. PD-1, PD-L1, and PD-L2 related genes were mainly enriched in biological procedures of T cell activation, cell adhesion, and other important lymphocyte effects. In addition, PD-1/PD-L1/PD-L2 was related with immune infiltration of CD8 T cells, cytotoxic lymphocytes,fibroblasts, and myeloid dendritic cells. Immune checkpoints of CTLA4, CD27, CD80, CD86, and CD28 were significantly related to the PD-1/PD-L1/PD-L2 axis. Clinically, PD-1 and PD-L2 expression was correlated with recurrence(P = 0.005 for both), but there was no significant correlation between their expression and HCC patient survival.CONCLUSION Mutations of key genes influence PD-1, PD-L1, and PD-L2 expression. PD-1, PDL1, and PD-L2 related genes participate in T cell activation, cell adhesion, and other important lymphocyte effects. The finding that PD-1/PD-L1/PD-L2 is related to immune infiltration and other immune checkpoints would expand our understanding of promising anti-PD-1 immunotherapy.

Research progress regarding programmed cell death 1/programmed cell death ligand 1 inhibitors combined with targeted therapy for treating hepatocellular carcinoma

In recent years,a number of targeted therapeutic agents have achieved success in phase III trials in patients with advanced hepatocellular carcinoma(HCC),including sorafenib,lenvatinib,and regorafenib.Immunotherapy is considered to be an effective treatment for advanced HCC.Immune checkpoint inhibitors targeting programmed cell death 1(PD-1)/programmed cell death ligand 1(PDL1)are important antitumor immunotherapy agents that represent breakthroughs in the treatment of advanced HCC.However,treating advanced HCC is still a great challenge,and the need for new treatments remains urgent.This review briefly summarizes the research progress in the use of PD-1/PD-L1 inhibitors combined with targeted therapy for treating HCC.

Advances in immuno-oncology biomarkers for gastroesophageal cancer:programmed death ligand 1,microsatellite instability,and beyond

Blockade of the programmed death ligand 1(PD-L1) and programmed cell death 1(PD-1) receptor axis represents an effective form of cancer immunotherapy. Preclinical evidence initially suggested that gastric and gastroesophageal junction(GEJ) cancers are potentially immunotherapy-sensitive tumors. Early phase clinical trials have demonstrated promising antitumor activity with PD-1/PD-L1 blockade in advanced or metastatic gastric/GEJ cancer. Microsatellite instability(MSI) and PD-L1 expression have been shown to predict higher response to PD-1 inhibitors as highlighted by the recent approvals of pembrolizumab in treatmentrefractory solid tumors with MSI status and the thirdline or greater treatment of PD-L1 positive advanced gastric/GEJ cancers. However, predictive and prognostic biomarkers remain an ongoing need. In this review, we detail the preclinical evidence and early tissue biomarker analyses illustrating potential predictive biomarkers to PD-1/PD-L1 blockade in gastric/GEJ cancer. We also review the clinical development of PD-1/PD-L1 inhibitors in gastric/GEJ cancer and highlight several areas in need of future investigation in order to optimize the efficacy of PD-1/PD-L1 blockade in gastric/GEJ cancer.

Use of programmed cell death protein ligand 1 assay to predict the outcomes of non-small cell lung cancer patients treated with immune checkpoint inhibitors

The recent discovery of immune checkpoints inhibitors, especially anti-programmed cell death protein 1(PD-1)and anti-programmed cell death protein ligand 1(PD-L1) monoclonal antibodies, has opened new scenarios in the management of non-small cell lung cancer(NSCLC) and this new class of drugs has achieved a rapid development in the treatment of this disease. However, considering the costs of these drugs and the fact that only a subset of patients experience long-term disease control, the identification of predictive biomarkers for the selection of candidates suitable for treatment has become a priority. The research focused mainly on the expression of the PD-L1 receptor on both tumor cells and/or immune infiltrates determined by immunohistochemistry(IHC). However, different checkpoint inhibitors were tested, different IHC assays were used, different targets were considered(tumor cells, immune infiltrates or both) and different expression thresholds were employed in clinical trials. In some trials the assay was used prospectively to select the patients, while in other trials it was evaluated retrospectively. Some confusion emerges, which makes it difficult to easily compare the literature data and to translate them in practice management. This mini-review shows the possibilities and pitfalls of the PD-L1 expression to predict the activity and efficacy of anti PD1/PD-L1 monoclonal antibodies in the treatment of NSCLC.

Clinical significance of programmed death 1/programmed death ligand 1 pathway in gastric neuroendocrine carcinomas

BACKGROUND Recently, more and more studies have demonstrated the pivotal role of programmed death 1/programmed death ligand 1(PD-1/PD-L1) pathway in the immune evasion of tumors from the host immune system. However, the role of PD-1/PD-L1 pathway in gastric neuroendocrine carcinomas(G-NECs) remains unknown.AIM To investigate the expression of PD-1/PD-L1 and role of PD-1/PD-L1 pathway in G-NECs, which occur rarely but are highly malignant and clinically defiant.METHODS We investigated the expression of PD-L1 on tumor cells and PD-1^+, CD8^+, and FOXP3^+ T cell infiltration by immunohistochemistry in 43 resected G-NEC tissue specimens. The copy number alterations of PD-L1 were assessed by qRT-PCR.RESULTS Most of the G-NECs tumor cells exhibited a near-uniform expression pattern of PD-L1, while some showed a tumor-stromal interface enhanced pattern. Of the 43G-NECs, 21(48.8%) were classified as a high PD-L1 expression group, and the high expression of PD-L1 was associated with poor overall survival(OS). The high expression of PD-L1 was correlated with abundant PD-1^+ tumor infiltrating lymphocytes(TILs) instead of CD8^+ TILs and FOXP3^+ regulatory T cells(Tregs).Our analysis also suggested that the infiltration of CD8^+ TILs tended to be a favorable factor for OS, although the difference did not reach the statistical significance(P = 0.065). Meanwhile, PD-L1 was significantly overexpressed in cases with copy number gain as compared with those without.CONCLUSION Our data demonstrated for the first time that high expression of PD-L1 in GNECs is associated with a poor prognosis, while the high expression may be due to the copy number variation of PD-L1 gene or stimulation of TILs. These results provide a basis for the immunotherapy targeting PD-1/PD-L1 pathway in GNECs.

Comprehensive insights into the effects and regulatory mechanisms of immune cells expressing programmed death-1/programmed death ligand 1 in solid tumors

The programmed cell death-1(PD-1)/programmed cell death ligand 1(PD-L1)signaling pathway is an important mechanism in tumor immune escape,and expression of PD-L1 on tumor cells has been reported more frequently.However,accumulating evidence suggests that PD-1/PD-L1 is also widely expressed on immune cells,and that regulation is also critical for tumor immune responses.In this review,we emphasized that under solid tumor conditions,the immunoregulatory effects of immune cells expressing PD-1 or PD-L1,affected the prognoses of cancer patients.Therefore,a better understanding of the mechanisms that regulate PD-1 or PD-L1 expression on immune cells would provide clear insights into the increased efficacy of anti-PD antibodies and the development of novel tumor immunotherapy strategies.

P-selectin glycoprotein ligand 1 deficiency prevents development of acute pancreatitis by attenuating leukocyte infiltration

BACKGROUND Acute pancreatitis(AP) is rapid-onset pancreatic inflammation that causes local and systemic inflammatory response syndrome(SIRS) with high morbidity and mortality, but no approved therapies are currently available. P-selectin glycoprotein ligand 1(PSGL-1) is a transmembrane glycoprotein to initiate inflammatory responses. We hypothesized that PSGL-1 may be involved in the development of AP and would be a new target for the treatment of AP.AIM To investigate the role and mechanism of PSGL-1 in the development of AP.METHODS The PSGL-1 expression on leukocytes was detected in peripheral blood of AP patients and volunteers. Pancreatic injury, inflammatory cytokines expression, and inflammatory cell infiltration was measured in AP mouse models induced with PSGL-1 knockout(PSGL-1-/-) and wild-type(PSGL-1+/+) mice. Leukocyteendothelial cell adhesion was measured in a peripheral blood mononuclear cell(PBMC)-endothelial cell coculture system.RESULTS The expression of PSGL-1 on monocytes and neutrophils was significantly increased in AP patients. Compared with PSGL-1+/+ mice, PSGL-1-/-AP mice induced by caerulein exhibited lower serum amylase, less Interleukin-1 beta(IL-1 beta) and Interleukin-6(IL-6) expression, less neutrophil and macrophage infiltration, and reduced peripheral neutrophil and monocyte accounts. PSGL-1 deficiency alleviated leukocyte-endothelial cell adhesion via IL-6 but not IL-1 beta.CONCLUSION PSGL-1 deficiency effectively inhibits the development of AP by preventing leukocyte-endothelial cell adhesion via IL-6 stimulation and may become a potential therapeutic target for treating AP.

Anti program death-1/anti program death-ligand 1 in digestive cancers

Human tumors tend to activate the immune system regulatory checkpoints as a means of escaping immunosurveillance. For instance, interaction between program death-1(PD-1) and program death-ligand 1(PD-L1) will lead the activated T cell to a state of anergy. PD-L1 is upregulated on a wide range of cancer cells. Anti-PD-1 and anti-PD-L1 monoclonal antibodies(m Abs), called immune checkpoint inhibitors(ICIs), have consequently been designed to restore T cell activity. Accumulating data are in favor of an association between PD-L1 expression in tumors and response to treatment. A PD-L1 expression is present in 30% to 50% of digestive cancers. Multiple anti-PD-1(nivolumab, pembrolizumab) and anti-PD-L1 m Abs(MPDL3280A, Medi4736) are under evaluation in digestive cancers. Preliminary results in metastatic gastric cancer with pembrolizumab are highly promising and phase Ⅱ will start soon. In metastatic colorectal cancer(CRC), a phase Ⅲ trial of MPDL3280 A as maintenance therapy will shortly be initiated. Trials are also ongoing in metastatic CRC with high immune T cell infiltration(i.e., microsatellite instability). Major challenges are ahead in order to determine how, when and for which patients we should use these ICIs. New radiologic criteria to evaluate tumor response to ICIs are awaiting prospective validation. The optimal therapeutic sequence and association with cytotoxic chemotherapy needs to be established. Finally, biomarker identification will be crucial to selection ofpatients likely to benefit from ICIs.

Levels of soluble delta-like ligand 1 in the serum and cerebrospinal fluid of tuberculous meningitis patients

In this study, the levels of soluble delta-like ligand 1 in cerebmspinal fluid and serum of 50 patients with tuberculous meningitis, 30 patients with viral meningitis, 20 patients with purulent meningitis and 40 subjects without central nervous system disease were determined using an enzyme-linked immunosorbent assay. The mean levels of soluble delta-like ligand 1 in both cerebrospinal fluid and serum from patients with tuberculous meningitis were significantly higher compared with those from patients with viral meningitis or purulent meningitis or from subjects without central nervous system disease. Meanwhile, the level of soluble delta-like ligand 1 gradually decreased as tuberculous meningitis patients recovered. If patients deteriorated after treatment, the level of soluble delta-like ligand 1 in cerebrospinal fluid gradually increased. There was no correlation between the level of soluble delta-like ligand 1 and the protein level/cell number in cerebrospinal fluid. Our findings indicate that the levels of soluble delta-like ligand 1 in cerebrospinal fluid and serum are reliable markers for the diagnosis of tuberculous meningitis and for monitoring treatment progress. At the same time, this index is not influenced by protein levels or cell numbers in cerebrospinal fluid.

Prognostic value of programmed death.1, programmed death-ligand 1, programmed death-ligand 2 expression, and CD8(+) T cell density in primary tumors and metastatic lymph nodes from patients with stage T1.4N+M0 gastric adenocarcinoma

Background: Anti-programmed death-1/programmed death-ligand 1(PD-1/PD-L1) immunotherapy has been proved to be effective on gastric cancer in ongoing clinical trials. However, the value of PD-L1 in predicting responses of patients with gastric cancer to anti-PD-1/PD-L1 immunotherapy is controversial. Some studies suggested that intra-and inter-tumoral heterogeneity of PD-L1 expression might explain the controversy.This study aimed to analyze the expression of PD-L1, PD-L2, and PD-1 as well as CD8(+) T-cell density in primary tumors and lymph nodes from patients with stage T1-4 N+M0 gastric adenocarcinoma to explore the heterogeneity of PD-1 signaling pathway molecules.Methods: In primary tumors and metastatic as well as non-metastatic lymph nodes from patients with stage T1-4 N+M0 gastric adenocarcinoma, we detected PD-L1 and PD-L2 expression with immunohistochemistry. CD8(+)T-cell density in primary tumors and PD-1 expression on CD8(+)T cells were detected with immunofluorescence. Univariate analysis was used to determine the prognostic values of them. Cox proportional hazard regression model was used to identify independent risk factors that affect patients' overall survival and disease-free survival.Results: Among 119 eligible patients who had undergone surgical resection, the positive rate of PD-L1 was higher in metastatic lymph nodes than in primary tumors(45.4% vs. 38.7%, P = 0.005); the positive rate of PD-1 on CD8(+)T cells was significantly higher in primary tumors and metastatic lymph nodes than in tumor-free lymph nodes(both P < 0.001). The intensity of PD-1 expression on CD8(+) T cells in primary tumors and in metastatic lymph nodes were stronger than that in tumor-free lymph nodes from the same patient. Beside, the positive rate of PD-L2 did not show any differences between primary tumors and metastatic lymph nodes. In multivariate analysis, PD-L1 expression,PD-L2 expression, a low density of CD8(+) T cells in primary tumors, and PD-1 expression on CD8(+) T cells in primary tumors were associated with poor prognosis.Conclusion: The expression of PD-L1 is heterogeneous in primary tumors and in metastatic lymph nodes from patients with stageT1-4 N+M0 gastric adenocarcinoma, which might explain the inconsistent results in assessing the prognostic value of PD-L1 expression in previous studies.

Highly active binuclear Cu(Ⅱ) catalyst bearing an unsymmetrical bipyridine-pyrazole-amine ligand for the azide-alkyne cycloaddition reaction

Ligands containing NH groups often show special characteristics.In this paper,a well-defined dinuclear Cu（II） complex bearing an unsymmetrical bipyridine-pyrazole-amine ligand was synthesized by the condensation of N–H to release H2O.Using sodium L-ascorbate as a reductant,the binuclear complex showed excellent activity in 1,3-dipolar cycloaddition reactions between alkynes and azides to obtain 1,4-disubstituted triazoles in 95%–99% isolated yields.

Pivotal role of long non-coding ribonucleic acid-X-inactive specific transcript in regulating immune checkpoint programmed death ligand 1 through a shared pathway between miR-194-5p and miR-155-5p in hepatocellular carcinoma

BACKGROUND Anti-programmed death therapy has thrust immunotherapy into the spotlight.However,such therapy has a modest response in hepatocellular carcinoma(HCC).Epigenetic immunomodulation is a suggestive combinatorial therapy with immune checkpoint blockade.Non-coding ribonucleic acid(ncRNA)driven regulation is a major mechanism of epigenetic modulation.Given the wide range of ncRNAs that co-opt in programmed cell-death protein 1(PD-1)/programmed death ligand 1(PD-L1)regulation,and based on the literature,we hypothesized that miR-155-5p,miR-194-5p and long non-coding RNAs(lncRNAs)X-inactive specific transcript(XIST)and MALAT-1 are involved in a regulatory upstream pathway for PD-1/PD-L1.Recently,nutraceutical therapeutics in cancers have received increasing attention.Thus,it is interesting to study the impact of oleuropein on the respective study key players.AIM To explore potential upstream regulatory ncRNAs for the immune checkpoint PD-1/PD-L1.METHODS Bioinformatics tools including microrna.org and lnCeDB software were adopted to detect targeting of miR-155-5p,miR-194-5p and lncRNAs XIST and MALAT-1 to PD-L1 mRNA,respectively.In addition,Diana tool was used to predict targeting of both aforementioned miRNAs to lncRNAs XIST and MALAT-1.HCC and normal tissue samples were collected for scanning of PD-L1,XIST and MALAT-1 expression.To study the interaction among miR-155-5p,miR-194-5p,lncRNAs XIST and MALAT-1,as well as PD-L1 mRNA,a series of transfections of the Huh-7 cell line was carried out.RESULTS Bioinformatics software predicted that miR-155-5p and miR-194-5p can target PDL1,MALAT-1 and XIST.MALAT-1 and XIST were predicted to target PD-L1 mRNA.PD-L1 and XIST were significantly upregulated in 23 HCC biopsies compared to healthy controls;however,MALAT-1 was barely detected.MiR-194 induced expression elevated the expression of PD-L1,XIST and MALAT-1.However,overexpression of miR-155-5p induced the upregulation of PD-L1 and XIST,while it had a negative impact on MALAT-1 expression.Knockdown of XIST did have an impact on PD-L1 expression;however,following knockdown of the negative regulator of X-inactive specific transcript(TSIX),PD-L1 expression was elevated,and abolished MALAT-1 activity.Upon co-transfection of miR-194-5p with siMALAT-1,PD-L1 expression was elevated.Co-transfection of miR-194-5p with siXIST did not have an impact on PD-L1 expression.Upon co-transfection of miR-194 with siTSIX,PD-L1 expression was upregulated.Interestingly,the same PD-L1 expression pattern was observed following miR-155-5p cotransfections.Oleuropein treatment of Huh-7 cells reduced the expression profile of PD-L1,XIST,and miR-155-5p,upregulated the expression of miR-194-5p and had no significant impact on the MALAT-1 expression profile.CONCLUSION This study reported a novel finding revealing that opposing acting miRNAs in HCC,have the same impact on PD-1/PD-L1 immune checkpoint by sharing a common signaling pathway.

The prognostic value of programmed cell death ligand 1expression in non-Hodgkin lymphoma:a meta-analysis

Objective: Although the prognostic value of programmed cell death-ligand 1(PD-L1) expression in non-Hodgkin lymphoma(NHL) has been evaluated in many studies, the results remain controversial. To investigate the prognostic role of PD-L1 expression and the association between PD-L1 expression and clinicopathological features of NHL, we performed a meta-analysis.Methods: The Pub Med, EMBASE, and Cochrane Library databases were searched up to November 30, 2017. The hazard ratio(HR), 95% confidence interval(CI), and odds ratios(OR) with 95% CIs were combined to evaluate the association of PD-L1 expression with overall survival(OS) and clinicopathological features. Review manager 5.3 and STATA 12.0 were used in this meta-analysis.Results: A total of 2,005 patients across nine studies were enrolled in our meta-analysis, and the pooled results showed that high PD-L1 expression was associated with a poor prognosis(HR=2.04, 95% CI: 1.18–3.54, P=0.01). In the subgroup analysis according to histology types, pooled results demonstrated that an increased PD-L1 expression was an unfavorable prognostic factor for diffuse large B-cell lymphoma(HR=1.92, 95% CI: 1.06–3.48, P=0.03) but not for natural killer/T-cell lymphoma(HR=2.41, 95%CI: 0.47–12.22, P=0.29). Pooled ORs indicated that PD-L1 expression was higher in NHL with international prognostic indices of≥3. However, PD-L1 expression had no correlation with gender, age, disease stage, lactate dehydrogenase level, B symptoms, and germinal center B-cell-like lymphoma.Conclusions: High PD-L1 expression was a poor prognostic biomarker in patients with NHL. Because of our limited sample size,high-quality studies with larger sample sizes are needed to validate our results.

Programmed death ligand-1 expression and its prognostic role in esophageal squamous cell carcinoma

AIM To investigate the expression and prognostic role of programmed death ligand-1(PD-L1) in locally advanced esophageal squamous cell carcinoma(ESCC).METHODS A total of 200 patients with ESCC who underwent radical esophagectomy with standard lymphadenectomy as the initial definitive treatment in Seoul National University Hospital from December 2000 to April 2013 were eligible for this analysis. Tissue microarrays were constructed by collecting tissue cores from surgical specimens, and immunostained with antibodies directed against PD-L1, p16, and c-Met. Medical records were reviewed retrospectively to assess clinical outcomes. Patients were divided into two groups by PD-L1 status, and significant differences in clinicopathologic characteristics between the two groups were assessed. RESULTS Tumor tissues from 67 ESCC patients(33.5%) were PDL1-positive. Positive p16 expression was observed in 21 specimens(10.5%). The H-score for c-Met expression was ≥ 50 in 42 specimens(21.0%). Although PDL1-positivity was not significantly correlated with any clinical characteristics including age, sex, smoking/alcoholic history, stage, or differentiation, H-scores for c-Met expression were significantly associated with PDL1-positivity(OR = 2.34, 95%CI: 1.16-4.72, P = 0.017). PD-L1 expression was not significantly associated with a change in overall survival(P = 0.656). In contrast, the locoregional relapse rate tended to increase(P = 0.134), and the distant metastasis rate was significantly increased(HR = 1.72, 95%CI: 1.01-2.79, P = 0.028) in patients with PD-L1-positive ESCC compared to those with PD-L1-negative ESCC.CONCLUSION PD-L1 expression is positively correlated with c-Met expression in ESCC. PD-L1 may play a critical role in distant failure and progression of ESCC.

Two Cobalt(II) Complexes Derived from the Hydrolysis Product of Di-Schiff Base Ligand N,N'-Bis-(1-benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine:Preparation,Characterization and Crystal Structure of the 6-Coordinate Species [CoL_2]X·H_2O (X = ClO_4^-, N

The reactions of Co（C1O4）2·6H2O and Co（NO3）2.6H2O with the di-Schiff base ligand N,N＇-bis-（1-benzimidazo-2-yl-ethylidene）-ethane-1,2-diamine （LA） in ethanol have been investigated. The reactions of LA with excess amount of cobalt salts yield the six-coordinate complexes [CoL2]（ClO4）E·H2O 1 and [CoL2]（NO3）E·H2O 2 as isolatable products （L= N-（1- benzimidazo-2-yl-ethylidene）-ethane-1,2-diamine）, where L is a tri-dentate mono-Schiff base ligand, resulting from the hydrolysis of the precursor di-Schiff base LA. Both complexes were characterized by X-ray crystallography. Crystal data for complex 1： monoclinic, space group P21/c, a = 11.9214（10）, b = 23.5828（17）, c = 14.0387（12）A, β = 135.219（4）°, C22H30Cl2CoN8O9, Mr = 680.37, V = 2780.1（4） A^3 ,Z = 4, Dc = 1.625 g/cm^3,μ（MoKa） = 0.876 mm^-1, F（000） = 1404, the final R = 0.0725 and wR = 0.1530 for 5726 observed reflections （I 〉 2σ（I））. Crystal data for complex 2： monoclinic, space group P21/c, a = 18.2162（16）, b = 10.0610（6）, c = 18.593（2）A, β = 130.099（3）°, C22H30CoN10O7, Mr = 605.49, V = 2606.5（4） A3 Z = 4, Dc = 1.543 g/cm^3,μ（MoKa） = 0.722 mm^-1, F（000） = 1260, the final R = 0.0619 and wR = 0.1429 for 5194 observed reflections （I 〉 2σ（I））. X-ray diffraction analysis reveals that each cobalt atom in the two complexes is chelated by six nitrogen atoms from two tridentate iigands L, exhibiting a slightly distorted octahedral coordination sphere. In both complexes, the strong hydrogen-bonding interactions between the lattice waters and N-H groups of the ligands result in 1D chains which are further connected by ClO4^- （or NO3^-） groups to form a 3D framework. In complex 2, the strong π-π interactions increase the stability of the structure.

Expression and clinical value of programmed cell death-ligand 1(PD-L1)in diffuse large B cell lymphoma:a retrospective study

Background: The programmed cell death-1(PD-1)/programmed cell death-ligand 1(PD-L1) pathway inhibits the activation of T cells and plays a crucial role in the negative regulation of cellular and humoral immune responses.Diffuse large B-cell lymphoma(DLBCL) is the most common lymphoid malignancy in adults. In the present study, we aimed to detect the expression of PD-L1 in DLBCL and to analyze its relationship with prognosis.Methods: We reviewed medical records of 204 newly diagnosed DLBCL patients in Sun Yat-sen University Cancer Center between October 2005 and August 2012. The expression of PD-L1 in tumor tissues from these 204 patients was detected using immunohistochemical(IHC) assay. The expression of anaplastic lymphoma kinase(ALK), CD5,CD30, and C-Myc in tumor specimens from 109 patients was detected using IHC, and Epstein-Barr virus(EBV)-encoded RNAs(EBERs) were detected using fluorescence in situ hybridization. The Spearman method was used for correlation analysis. The Kaplan-Meier method with log-rank test was used for univariate analysis. Cox proportional hazards model was used for multivariate analysis.Results: Of the 204 patients, 100(49.0%) were PD-L1-positive in tumor cells and 44(21.6%) were PD-L1-positive in tumor microenvironment. PD-L1 expression in tumor cells and tumor microenvironment were more common in the non-germinal center B-cell-like(GCB) subtype than in the GCB subtype(P = 0.02 and P= 0.04). Patients with PD-L1 expression in tumor microenvironment were more likely to be resistant to first-line chemotherapy when compared with the patients without PD-L1 expression in tumor microenvironment(P = 0.03). PD-L1 expression in tumor microenvironment was negatively correlated with C-Myc expression(r =-0.20, P = 0.04). No correlations were detected between PD-L1 expression and the expression of ALK, CD5, and CD30 as well as EBERs. The 5-year overall survival(OS)rates were 50.0% and 67.3% in patients with and without PD-L1 expression in tumor cells(P = 0.02). PD-L1 expression in tumor cells was an independent risk predictor for OS(P < 0.01).Conclusions: PD-L1 expression is more common in the non-GCB subtype than in the GCB subtype. PD-L1 expression in tumor microenvironment has a negative correlation with C-Myc. PD-L1 positivity predicts short survival in DLBCL patients. For patients with PD-L1 expression, more strategy such as anti-PD-L1 antibody treatment should be recommended.

Pathological significance of abnormal recepteur d'origine nantais and programmed death ligand 1 expression in colorectal cancer

BACKGROUND Programmed death ligand 1(PD-L1) immunotherapy remains poorly efficacious in colorectal cancer(CRC). The recepteur d'origine nantais(RON) receptor tyrosine kinase plays an important role in regulating tumor immunity.AIM To identify the patterns of RON and PD-L1 expression and explore their clinical significance in CRC.METHODS Gene expression data from the Gene Expression Omnibus database(GEO;n = 290) and patients at the First Affiliated Hospital, Zhejiang University School of Medicine(FAHZUSM;n = 381) were analyzed to determine the prognostic value of RON and PD-L1 expression within the tumor microenvironment of CRC. HT29 cell line was treated with BMS-777607 to explore the relationship between RON activity and PD-L1 expression. Signaling pathways and protein expression perturbed by RON inhibition were evaluated by cellular immunofluorescence and Western blot.RESULTS In the GEO patient cohort, cut-off values for RON and PD-L1 expression were determined to be 7.70 and 4.3, respectively. Stratification of patients based on these cutoffs demonstrated that high expression of RON and PD-L1 was associated with a poor prognosis. In the FAHZUSM cohort, rates of high expression of RON in tumor cells, high PD-L1 expression in tumor cells and tumor infiltrating monocytes, and both high RON and high PD-L1 expression in the tumor microenvironment were 121(32%), 43(11%), 91(24%), and 51(13.4%), respectively. High expression of RON was significantly correlated with high expression of PD-L1 in the tumor cell compartment(P < 0.001). High expression of RON and that of PD-L1 were independent prognostic factors for poorer overall survival. Concurrent high expression of both RON and PD-L1 in the tumor microenvironment was significantly associated with a poor prognosis. In vitro, BMS-777607 inhibited the phosphorylation of RON, inhibited PD-L1 expression, and attenuated activation of the ERK1/2 and AKT signaling pathways in CRC cells.CONCLUSION RON, PD-L1, and their crosstalk are significant in predicting the prognostic value of CRC. Moreover, phosphorylation of RON upregulates PD-L1 expression, which provides a novel approach to immunotherapy in CRC.