How to use anti-PD-1 therapy in gastric cancer: the approach in the United States

Gastric cancer is a leading global cause of cancer-related mortality. In the past, survival achieved in metastatic disease with chemotherapy was less than 1 year. The advent of immune checkpoint inhibitors has changed the treatment of gastric cancer. With demonstration of single agent activity for anti-programmed cell death protein 1 (anti-PD-1) agents in gastric cancer with a particularly high degree of activity in microsatellite instability (MSI) high cancers, global clinical trials added nivolumab and pembrolizumab to first line chemotherapy. Improvements in progression free survival, overall survival and increased response rates led to regulatory approval of these agents in the U.S. The benefit in survival seems limited, however, to patients with programmed cell death ligand 1 (PD-L1) positive or MSI high cancers. Adjuvant therapy with nivolumab improved disease-free survival after chemoradiotherapy and surgery in esophageal and gastroesophageal junction adenocarcinoma in patients with residual disease resected at surgery, and is a new care standard. Results of ongoing trials adding immune checkpoint inhibitors to perioperative chemotherapy in gastric cancer are anxiously awaited. In locally advanced MSI high gastric cancer, immune checkpoint inhibitor therapy is being explored as preoperative therapy given the demonstration of a high degree of pathologic complete response to these agents. Some trials may offer patients nonoperative management if a complete response is achieved.

Expression of tumoral GSK3-β, PD-L1, and CD8 cell density in urothelial carcinomas, association with tumor grade and overall survival

Bladder cancer is the most common malignancy in the urinary tract, and is biologically and clinically quite heterogeneous. Around 90% of diagnoses are made in the 6th decade, being more prevalent in males. The programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1) axis play a putative role in immune checkpoint and as a means through which cancer evades the immune system. Inhibition of the glicogênio synthase kinase (GSK) 3 leads to the downregulation of PD-1 via upregulation of the transcription factor Tbet. The use of biomarkers PD-L1 and GSK-3β and evaluation of the immune infiltrate have very promising correlations with urothelial carcinoma prognosis and treatment prediction.

OBJECTIVE

To investigate the protein expression of PD-L1 and GSK-3β and the CD8-positive immune infiltrates in bladder carcinomas.

MATERIALS AND METHODS

This was a cross-sectional study of 140 samples of urothelial carcinomas from 2015 to 2018. Automated digitally assisted scoring and conventional analyses of the markers of GSK-3β (27C10), CD8 (7103β) and PDL-1 (22c3), were reviewed by two pathologists independently and a histologic score was calculated. The density of CD8 was also measured.

RESULTS

The immunoexpression of GSK-3β (91%) was presented in most samples, PD-L1 in 62.9% and CD8 cells present in 46.3% of cases. When analyzed in conjunction, the levels of GSK-3β and PD-L1 (P = 0.033), and CD8 and PD-L1 (P<0.002) showed significant correlations. No significant associations were observed between GSK-3β and CD8. The positivity of GSK-3β and PD-L1 was predominant in high-grade tumors.

CONCLUSION

Despite the tumor microenvironment heterogeneity, the expression of CD8, GSK-3β and PDL1 could be valuable and GSK-3β could be a potential target in advanced bladder cancer, especially in the context of immunotherapy.

Recent Advances in Perioperative Immunotherapies in Lung Cancer

Several clinical trials have been revolutionizing the perioperative treatment of early-stage non-small cell lung cancer (NSCLC). Many of these clinical trials involve cancer immunotherapies with antibody drugs that block the inhibitory immune checkpoints programmed death 1 (PD-1) and its ligand PD-L1. While these new treatments are expected to improve the treatment outcome of NSCLC patients after pulmonary resection, several major clinical questions remain, including the appropriate timing of immunotherapy (neoadjuvant, adjuvant, or both) and the identification of patients who should be treated with neoadjuvant and/or adjuvant immunotherapies, because some early-stage NSCLC patients are cured by surgical resection alone. In addition, immunotherapy may induce immune-related adverse events that will require permanent treatment in some patients. Based on this fact as well, it is desirable to select appropriate patients for neoadjuvant/adjuvant immunotherapies. So far, data from several important trials have been published, with findings demonstrating the efficacy of adjuvant atezolizumab (IMpower010 trial), neoadjuvant nivolumab plus platinum-doublet chemotherapy (CheckMate816 trial), and several perioperative (neoadjuvant plus adjuvant) immunotherapies (AEGEAN, KEYNOTE-671, NADIM II, and Neotorch trials). In addition to these key trials, numerous clinical trials have reported a wealth of data, although most of the above clinical questions have not been completely answered yet. Because there are so many ongoing clinical trials in this field, a comprehensive understanding of the results and/or contents of these trials is necessary to explore answers to the clinical questions above as well as to plan a new clinical trial. In this review, we comprehensively summarize the recent data obtained from clinical trials addressing such questions.

The predictive implication of programmed cell death ligand 1 expression in extranodal natural killer/T-Cell lymphoma and its correlation with clinicopathological features: a systematic review and meta-analysis

Background

Although programmed cell death ligand 1 (PD-L1) expression and function in hematologic malignancies have aroused extensive attention, its prognostic value for extranodal natural killer/T-cell lymphoma (ENKTL) is still unknown. Therefore, we conducted this meta-analysis to explore the predictive value of neoplastic PD-L1 expression for ENKTL.

Methods

The PubMed, Embase, Web of Science, and CNKI databases were searched to identify eligible observational studies reporting PD-L1 expression and survival outcomes of ENKTL patients. The search was conducted in accordance with the Meta-analyses Of Observative Studies in Epidemiology (MOOSE) guidelines. The pooled hazard ratios (HRs) and 95% confidence intervals (95% CIs) were adopted to analyze survival outcomes, and the odds ratios (ORs) and 95% CIs were adopted for clinicopathological parameters. Review Manager 5.3 and STATA 17.0 were used for statistical analysis. Potential publication bias was evaluated by funnel plot and Egger's test.

Results

A total of 433 patients with ENKTL were included across seven studies. The pooled results showed no significant relationship between neoplastic PD-L1 expression and overall survival (OS) (HR =1.35, 95% CI: 0.49-3.75, P=0.559). We also performed subgroup analyses. However, increased PD-L1 expression was associated with a low international prognostic index (IPI) score of 0-1 (OR =2.46; 95% CI: 1.11-5.45, P=0.03), good performance status (OR =1.97; 95% CI: 1.11-3.51, P=0.02), and a good treatment effect (OR =2.61; 95% CI: 1.01-6.70, P=0.05).

Conclusions

PD-L1-positive expression in patients with ENKTL was correlated with favorable clinical features. Thus, PD-L1-positive expression appears to be a potential predictor of treatment benefits. Additional large-scale, high-quality studies are needed to further explore its predictive value.

Relationship between PD-L1 expression and molecular aberrances in lung adenocarcinoma with solid components

Background

Previous studies have evaluated the expression of programmed cell death ligand 1 (PD-L1) in terms of genetic mutation in lung adenocarcinoma (LUAD). However, there are no corresponding large-sample studies in Chinese patients with LUAD with solid components (LUAD-SC). Furthermore, it remains unknown whether the relationship that exists between PD-L1 expression levels and clinicopathological and molecular profiles in small biopsy specimens is consistent with that in surgically-resected specimens. The present study explored the clinicopathological features and genetic correlation of PD-L1 expression in LUAD-SC.

Methods

We collected 1,186 LUAD-SC specimens from Fudan University, Zhongshan Hospital. The tumors were divided into PD-L1 negative, low, and high groups according to the tumor proportion score (TPS)-assessed expression of PD-L1. The mutational information of all specimens was assessed. Each group's clinicopathological features were also assessed. The relationship between PD-L1 expression levels and clinicopathological features, the overlap with driver genes and the prognostic value were analyzed.

Results

In 1,090 resected specimens, a high PD-L1 expression level was more prevalent in the group with predominant SCs, which was remarkably correlated with lymphovascular invasion and a more advanced clinical stage. In addition, the PD-L1 expression level was significantly related to EGFR, KRAS, and BRAF mutations and ROS1 fusions. Meanwhile, in 96 biopsy specimens, the solid-dominant type and EGFR showed a significant difference in PD-L1 expression. Furthermore, compared with their resected counterparts, the biopsy specimens were significantly associated with solid predominant, advanced tumor-node-metastasis (TNM) stage, and high PD-L1 expression. Finally, high PD-L1 expression can be considered a poor prognostic factor for overall survival (OS).

Conclusions

LUAD-SC with high PD-L1 expression levels is linked to unique clinicopathologic characteristics as well as driver mutations. It is important to evaluate the percentage of solid components in both punctured and excised specimens, which may help identify cases of high PD-L1 expression.

Computational Approaches Drive Developments in Immune-Oncology Therapies for PD-1/PD-L1 Immune Checkpoint Inhibitors

Computational approaches in immune-oncology therapies focus on using data-driven methods to identify potential immune targets and develop novel drug candidates. In particular, the search for PD-1/PD-L1 immune checkpoint inhibitors (ICIs) has enlivened the field, leveraging the use of cheminformatics and bioinformatics tools to analyze large datasets of molecules, gene expression and protein-protein interactions. Up to now, there is still an unmet clinical need for improved ICIs and reliable predictive biomarkers. In this review, we highlight the computational methodologies applied to discovering and developing PD-1/PD-L1 ICIs for improved cancer immunotherapies with a greater focus in the last five years. The use of computer-aided drug design structure- and ligand-based virtual screening processes, molecular docking, homology modeling and molecular dynamics simulations methodologies essential for successful drug discovery campaigns focusing on antibodies, peptides or small-molecule ICIs are addressed. A list of recent databases and web tools used in the context of cancer and immunotherapy has been compilated and made available, namely regarding a general scope, cancer and immunology. In summary, computational approaches have become valuable tools for discovering and developing ICIs. Despite significant progress, there is still a need for improved ICIs and biomarkers, and recent databases and web tools have been compiled to aid in this pursuit.

Programmed Cell Death Protein 1 (PD-1) in Relation to PANoptosis: Immune Pharmacological Targets for Management of Breast Adenocarcinoma

Programmed cell death protein 1 or Programmed death-1 (PD-1) and Programmed Cell Death Ligand 1 (PD-L1) research have tremendously been taken into great consideration in the field of cancer immune pharmacology. Cancer immunotherapy has been convoyed by a capable outcome over the past few years. PD-1 and PD-L1 play a pivotal role in attenuating immune involvement, modulating the activity of T-cells, and promoting different types of programmed cell death. Participation of antigen-specific T cells and regulatory T cells and their acute mutations during cancer cell invasion and migration may lead to challenges for three programmed cell death methods, namely, pyroptosis, apoptosis, and necroptosis called "PANoptosis". This review aimed to explore the correlation between the PD-1/PD-L1 pathway in "PANoptosis" using available recently published literature with several schematic representations. Hopefully, the review will facilitate the biomedical scientist targeting cancer immune pharmacological aspect for the management of Breast Adenocarcinoma shortly.

Programmed cell death ligand 1 expression on monocytes is inversely correlated with tumour response to preoperative chemoradiotherapy for locally advanced rectal cancer

AIM

The clinical efficacy of chemoradiotherapy (CRT) is largely dependent on host immune status. The aim of this study was to identify possible markers expressed on circulating mononuclear cells to predict tumour response in patients with locally advanced rectal cancer (LARC).

METHODS

Peripheral blood samples were obtained from 47 patients diagnosed with LARC before and after CRT. The numbers of lymphocytes and monocyte subsets were analysed using flow cytometry. Based on clinical and pathological findings, patients were classified as high or low responders.

RESULTS

Lymphocyte counts were markedly decreased after CRT. Total numbers of lymphocytes (p = 0.030) and CD4(+) T cells (p = 0.041) in post-CRT samples were significantly lower in low responders than in high responders. In contrast, monocyte counts were not reduced and the number of CD14^dim (+) CD16(+) nonclassical (patrolling) monocytes were somewhat increased after CRT (p = 0.050). Moreover, the ratios of programmed cell death ligand 1 (PD-L1) (+) cells on patrolling monocytes before and after CRT were significantly higher in low responders than in high responders (p = 0.0046, p = 0.0006). The same trend was observed for classical and intermediate monocytes. The expression of PD-L1 on patrolling monocytes before CRT correlated inversely with the number of T cells and natural killer (NK) cells after CRT. PD-L1(+) ratio in patrolling monocytes was an independent predictor for response to CRT.

CONCLUSION

Programmed cell death ligand 1 (PD-L1) expression on patrolling monocytes suppresses cell-mediated immunity in patients receiving CRT which could be related to tumour response, and may be a useful biomarker for decision-making in the management of patients with LARC.

A Novel Sushi-IL15-PD1 CAR-NK92 Cell Line With Enhanced and PD-L1 Targeted Cytotoxicity Against Pancreatic Cancer Cells

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive and lethal malignancy with a limited response to current therapies. Novel and effective treatment is urgently needed. Herein, a chimeric antigen receptor (CAR)-NK92 cell line, with an interleukin (IL)-15Rα-sushi/IL-15 complex and a Programmed cell death-1(PD1) signal inverter was constructed and named SP (Sushi-IL15-PD1). We showed that CAR expression enabled SP cells to proliferate independently of IL-2 and became more resistant to nutrition starvation-induced apoptosis. Meanwhile, SP cells were more effective than NK92 in PDAC cell killing assays in vitro and in vivo, and there was a positive correlation between the killing capability of SP cells and PD-L1 expression in pancreatic cancer cells. Based on the synergistic and comprehensive effects of the special CAR structure, the adhesion, responsiveness, degranulation efficiency, targeted delivery of cytotoxic granule content, and cytotoxicity of SP cells were significantly stronger than those of NK92. In conclusion, the SP cell line is a promising adoptive immunotherapy cell line and has potential value as an adjuvant treatment for pancreatic cancer, especially in patients with high PD-L1 expression.

Programmed Cell Death Ligand 1-Expressing Circulating Tumor Cells: A New Prognostic Biomarker in Non-Small Cell Lung Cancer

BACKGROUND

In non-small cell lung cancer (NSCLC), analysis of programmed cell death ligand 1 (PD-L1) expression in circulating tumor cells (CTCs) is a potential alternative to overcome the problems linked to the tumor biopsy spatiotemporal heterogeneity. However, the prognostic significance of PD-L1-positive [PD-L1(+)] CTCs remains controversial.

METHODS

We prospectively evaluated the correlation with clinicopathological variables and prognostic value of PD-L1(+) CTCs, detected with the FDA-cleared CellSearch® system, in 54 patients with advanced NSCLC.

RESULTS

We detected CTCs and PD-L1(+) CTCs in 43.4% and 9.4% of patients with NSCLC. PD-L1 expression concordance between tumor tissue and CTCs was low (54%). The presence of PD-L1(+) CTC correlated with the absence of gene alterations in tumor tissue and with poor prognosis-related biological variables (anemia, hyponatremia, increased lactate dehydrogenase). In univariate analysis, absence of gene alterations, number of metastatic sites, prior systemic therapies, and presence of CTCs and PD-L1(+) CTCs were associated with worse overall survival, whereas PD-L1 expression in tumor tissue was not. In multivariate analysis, squamous cell carcinoma histology, number of prior systemic treatments, and the presence of CTC were significantly associated with overall survival. Survival was worse in patients with PD-L1(+) CTCs than in patients with PD-L1-negative CTC or without any CTC.

CONCLUSIONS

Our study suggests that the presence of PD-L1(+) CTCs is associated with poor prognosis in patients with advanced NSCLC. Studies with larger samples are needed to confirm our results and to determine how PD-L1(+) CTC detection could help to predict the response or resistance to anti-PD-1/PD-L1 therapies.Clinical trial registration NCT02866149.

Epstein-Barr Virus Positive B-Cell Lymphoproliferative Disorder of the Gastrointestinal Tract

Epstein-Barr virus positive B-cell lymphoproliferative disorder (EBV+ B-LPD) encompasses a broad clinicopathological spectrum and distinct clinical behavior that relatively favors the gastrointestinal (GI) tract. In this review, we provide an update on the clinicopathological features and biological behavior of EBV-positive mucocutaneous ulcer (EBVMCU) and primary EBV+ diffuse large B-cell lymphoma (DLBCL) of the GI tract. EBVMCU is a newly recognized entity but well known as an indolent and self-limited EBV+ B-LPD occurring in various immunodeficiencies. In contrast, EBV+ DLBCL constitutes the largest group of EBV+ B-LPDs and is regarded as an aggressive neoplasm. These two distinct diseases have historically been distinguished in the reappraisal of age-related EBV-associated B-LPDs but are challenging in routine practice regarding their differential diagnostic and therapeutic approaches. An increasing number of reports indicate that they are epidemiologically prevalent beyond western and eastern countries, but their comprehensive analysis is still limited. We also describe the PD-L1 positivity of tumorous large cells and non-malignant immune cells, which is relevant for the prognostic delineation among patients with primary DLBCL of the GI tract with and without EBV on tumor cells.

Differences in treatment effect size between progression-free survival and overall survival in anti-PD-1/PD-L1 inhibitors-based trials in advanced NSCLC: a systematic review and meta-analysis

Background

To investigate the differences in treatment effect sizes between progression-free survival (PFS) and overall survival (OS) in advanced non-small cell lung cancer (NSCLC) treated with programmed cell death 1 (PD-1) and its ligand (PD-L1) blockade-based treatments.

Methods

The differences in treatment effect sizes between PFS and OS were assessed by using a ratio of hazard ratio (rHR): the HR for PFS to that for OS. A random effects meta-analysis across trials was conducted to generate the combined rHR. We also evaluated the feasibility of adopting PFS as the surrogate of OS by using Spearman correlation coefficient (R) between logHR_PFS and logHR_OS.

Results

A total of 27 randomized controlled trials (RCTs) with 15,590 patients were included. Treatment effect sizes were comparable, on average, for OS than for PFS (pooled rHR, 0.98; 95% CI, 0.91 to 1.08). Subgroup analysis revealed that treatment effect sizes were greater for OS than for PFS for trials with immunotherapy as second or above line treatment (rHR, 1.17; 95% CI, 1.06 to 1.29), while the differences were greater for PFS than for OS for trials with immunotherapy as first-line setting (rHR, 0.91; 95% CI, 0.84 to 0.99; P_interaction<0.01). The coefficient of determination was 40% and R was 0.63 between logHR_PFS and logHR_OS. Subgroup analysis showed that coefficient of determination and R were 62% and 0.79 in trials with immunotherapy as first-line setting, 22% and 0.47 in trials with immunotherapy as second or above line treatment, respectively.

Discussion

Treatment effect sizes between PFS and OS were roughly consistent in trials with different anti-PD-(L)1 inhibitor-based therapies. PFS could be a potential alternative endpoint for OS in trials with immunotherapy as first-line setting, but PFS should be cautiously interpreted without OS data for trials with immunotherapy as second or above line treatment.

Rational Design of Hyaluronic Acid-Based Copolymer-Mixed Micelle in Combination PD-L1 Immune Checkpoint Blockade for Enhanced Chemo-Immunotherapy of Melanoma

The application of combinational therapy breaks the limitation of monotherapy and achieves better clinical benefit for tumor therapy. Herein, a hyaluronic acid/Pluronic F68-based copolymer-mixed micelle was constructed for targeted delivery of chemotherapeutical agent docetaxel (PHDM) in combination with programmed cell death ligand-1(PD-L1) antibody. When PHDM+anti-PDL1 was injected into the blood system, PHDM could accumulate into tumor sites and target tumor cells via CD44-mediated endocytosis and possess tumor chemotherapy. While anti-PDL1 could target PD-L1 protein expressed on surface of tumor cells to the immune checkpoint blockade characteristic for tumor immunotherapy. This strategy could not only directly kill tumor cells but also improve CD8+ T cell level and facilitate effector cytokines release. In conclusion, the rational-designed PHDM+anti-PDL1 therapy strategy creates a new way for tumor immune-chemotherapy.

Salvage camrelizumab plus apatinib for relapsed esophageal neuroendocrine carcinoma after esophagectomy: a case report and review of the literature

The current evidence regarding immunotherapy plus targeted therapy in esophageal neuroendocrine carcinoma (NEC) is lacking. Camrelizumab is a programmed cell death protein 1 inhibitor. Apatinib is a selective tyrosine kinase inhibitor of vascular endothelial growth factor receptor-2. A 50-year-old female was initially diagnosed as primary esophageal NEC. Neoadjuvant chemotherapy and Ivor Lewis esophagectomy were performed (ypT3N0M0, stage Ⅱ). Twenty months after the surgery, an isolated mediastinal lymph node recurrence of NEC was recorded. The specimen revealed a positive expression of vascular endothelial growth factor and programmed cell death ligand 1. The diseased lymph node was slightly enlarged after two cycles of first-line paclitaxel liposome and S-1. Second-line apatinib and S-1 for 2 months also resulted in progressive disease. Subsequently, third-line camrelizumab plus apatinib was continued for 5 months. The patient demonstrated a progression-free status for more than 10 months following the combination therapy. Meanwhile, relevant studies of camrelizumab in gastric or esophageal cancer were briefly reviewed. Based on the current evidence, camrelizumab is a promising agent for esophageal cancer. More prospective trials are warranted before a definite recommendation could be drawn.

PD-L1 expression with respect to driver mutations in non-small cell lung cancer in an Asian population: a large study of 1370 cases in China

Background

Programmed cell death ligand 1 (PD-L1) expression with respect to genetic alternations has not been well established in non-small cell lung cancer (NSCLC), especially in the Asian population.

Methods

We reviewed 1370 NSCLC patients from a prospectively maintained database. Immunohistochemistry was performed on tumor cells and tumor-infiltrating lymphocytes (TILs) using the VENTANA (SP142) anti-PD-L1 antibody. The tumor proportion score (TPS) cutoff values were set at ⩾1% and ⩾50%, and the immune proportion score (IPS) cutoff values were set at ⩾1% and ⩾10%.

Results

In tumor cells, PD-L1 positivity was observed in 405 (29.6%), 122 (8.9%), and 27 (2.0%) patients with TPS cutoff values at ⩾1% and ⩾50%. Contrastingly, TILs of 1154 (84.2%) and 346 (25.3%) patients stained positive at IPS cutoff values of ⩾1% and ⩾50%, respectively. PD-L1 expression was more common in patients who were mutation-negative irrespective of the TPS cutoff values and tumor size. PD-L1 expression in tumor cells was less frequent in patients harboring EGFR mutations (18.8% TPS ⩾ 1% and 4.6% TPS ⩾ 50%). Conversely, PD-L1 expression was high in the presence of KRAS mutations (47.3% TPS ⩾ 1% and 22.5% TPS ⩾ 50%). Overall, KRAS, BRAF, PICK3A, MET mutations and ROS1 and RET translocations were more frequent, while EGFR and HER2 mutations and ALK translocations were less frequent compared with the overall PD-L1 expression levels. Although the difference between TILs among the PD-L1-positive cases was comparatively small, PD-L1 positivity was less prevalent in EGFR-mutated tumors and more common in those with KRAS mutations, ROS1 translocations, BRAF mutations, or MET mutations.

Conclusion

Our study showed the heterogeneity in PD-L1 expression with respect to nine major oncogenic drivers in China. Future studies are warranted to further clarify the association between PD-L1 expression and driver mutations in NSCLC.

Protein tyrosine phosphatase receptor type delta (PTPRD) suppresses the expression of PD-L1 in human hepatocellular carcinoma by down-regulating STAT3

BACKGROUND

Protein tyrosine phosphatase receptor type delta (PTPRD) is a tumor suppressor that is often inactivated in hepatocellular carcinoma (HCC). However, the mechanisms of how PTPRD inhibits HCC are not well understood. Programmed cell death ligand 1 (PD-L1), an immune checkpoint, plays a seminal role in the regulation of carcinogenesis of HCC. The sustained activation of STAT3 is closely related to PTPRD deletion and PD-L1 overexpression; however, whether there is a relationship between PTPRD and PD-L1 expression in HCC has not been investigated. This study aims to investigate the relationship between PTPRD and PD-L1 in HCC samples and illuminate potential new molecular mechanisms of PTPRD effects on PD-L1 in HepG2 cells.

METHODS

We collected 16 pairs of tumorous tissues and adjacent normal tissues from HCC patients. The mRNA and protein expression levels of PTPRD and PD-L1 in the HCC tissues were detected by RT-PCR and Western blot analysis. Next, Spearman's correlation analysis was performed to evaluate the relationship between PTPRD and PD-L1. Then, we transfected the overexpressed or knocked-down PTPRD genes into the HepG2 cell line, and the effects of PTPRD on PD-L1 in HCC cells were evaluated. The activity from the STAT3 and p-STAT3 in the HepG2 cells transfected with PTPRD gene overexpression and knockdown was determined by Western blotting tests.

RESULTS

The expression of PTPRD was significantly down-regulated in the HCC tissues compared with the adjacent control tissues; however, PD-L1 was significantly higher in the HCC tissues. There was a negative correlation between PTPRD and PD-L1 expression in the HCC tissues. PTPRD over-expression significantly inhibited PD-L1 expression; meanwhile, PTPRD depletion promoted PD-L1 expression in the HepG2 cells. Furthermore, PTPRD over-expression significantly inhibited the expression of STAT3 and p-STAT3, while PTPRD depletion promoted these cytokines. Our studies revealed that PTPRD repressed PD-L1 expression in the HepG2 cells, which might occur via the STAT3 pathway.

CONCLUSIONS

The results from our study show that PTPRD and PD-L1 are negatively correlated in HCC tissues. PTPRD suppresses PD-L1 expression in HepG2 cells by down-regulating STAT3. These findings are expected to become a new target for the immunotherapy of HCC.

Anti-PD-1 antibody camrelizumab plus doxorubicin showed durable response in pulmonary sarcomatoid carcinoma: Case report and literature review

WHAT IS KNOWN AND OBJECTIVE

Pulmonary sarcomatoid carcinoma (PSC) is characterized by dismal prognosis and resistance to platinum-based chemotherapy. The immune checkpoint inhibitors showed promising efficacy in the treatment of PSC. Camrelizumab is a programmed cell death protein 1 inhibitor; however, current evidence of its efficacy in PSC is lacking.

CASE SUMMARY

A 47-year-old female non-smoker presented with central-type masses in the right upper and lower lobes. PSC (cT4N2M0, stage IIIB) with positive expression of programmed death ligand-1 was diagnosed. First-line camrelizumab plus doxorubicin and cisplatin was introduced, followed by camrelizumab monotherapy due to grade 4 leukopenia and thrombocytopenia during the combination therapy. The lesions indicated a partial remission which endured for more than 20 months.

WHAT IS NEW AND CONCLUSION

Camrelizumab plus doxorubicin and cisplatin regimen is a promising option for PSC patients. Further high-quality trials are warranted.

The prevalence and prognostic and clinicopathological value of PD-L1 and PD-L2 in renal cell carcinoma patients: a systematic review and meta-analysis involving 3,389 patients

Background

The research of the prognostic and clinicopathologic values of programmed cell death ligand 1/2 (PD-L1/2) in renal cell carcinoma (RCC) patients has been mired by a dearth of studies and considerable controversy. We thus conducted a systematic review and meta-analysis to report the prevalence and prognostic and clinicopathological value of programmed cell death ligand 1 (PD-L1) and programmed cell death-legend 2 (PD-L2) in RCC patients.

Methods

The PubMed, Cochrane Library, EMBASE databases were searched to find human studies limited to English language literature published through October 1, 2019. Using random or fixed effects models, hazard ratios (HRs) and 95% confidence intervals (CIs) were evaluated to explore the prognostic value of PD-Ls expression, while odds ratios (ORs) and 95% CIs were evaluated to investigate clinicopathological parameters. The protocol of the study was registered in PROSPERO (CRD42019135199).

Results

After pooling all 16 eligible studies comprising 3,389 patients, we found that the overall prevalence of PD-L1 and PD-L2 in RCC patients was 27% and 39%, respectively. Furthermore, PD-L1 over-expression was a strong negative predictor for overall survival (OS), disease-free survival/progression-free survival (DFS/PFS), and cancer-specific survival (CSS) in renal cell carcinoma patients (HR =2.86, 95% CI: 1.83–4.47, P<0.001; HR =2.64, 95% CI: 1.99–3.52, P<0.001; HR =2.78, 95% CI: 2.17–3.56, P<0.001). Meanwhile, PD-L2 over-expression was only a weak negative predictor for CSS (HR =1.66, 95% CI: 1.05–2.65, P<0.05). Subgroup analysis showed that Caucasians had worse OS (HR =3.60, 95% CI: 1.77–7.33, P<0.001), PFS (HR =3.56, 95% CI: 2.44–5.18, P<0.001), and CSS (HR =3.13, 95% CI: 2.37–4.14, P<0.001) than Asians. PD-L1 was a strong indicator for worse prognosis (P<0.05 for all), while PD-L2 over-expression was only associated with sarcomatoid features (presence vs. absence, OR =1.80, 95% CI: 1.13–2.86, P=0.014). Notably, PD-L1 overexpression was more prevalent in women (male vs. female, OR =0.68, 95% CI: 0.51–0.90, P=0.006).

Conclusions

Higher PD-L1 expression is more closely associated with poor prognosis and more advanced clinicopathological features in RCC patients than PD-L2, especially in women and Caucasian patients. PD-L2 was a weak negative predictor of poor CSS of RCC and was not a prompt for the metastasis of RCC.

Retrospective analysis of the prognostic value of PD-L1 expression and 18F-FDG PET/CT metabolic parameters in colorectal cancer

Background: It has been rarely reported whether ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) uptake in colorectal cancer cells is associated with the expression of PD-L1. We performed a clinical pathology study to evaluate PD-L1 expression in patients undergoing surgical resection of colorectal cancer with preoperative ¹⁸F-FDG PET/CT imaging, with the aim of predicting the response of CRC patients to immune checkpoint inhibitors.

Material and Methods: A retrospective analysis of patients with CRC who underwent FDG-PET imaging before surgery was performed to measure the parameters of FDG-PET imaging: the maximum standardized uptake value (SUVmax), the metabolic tumor volume (MTV), and the total lesion glycolysis (TLG) were evaluated to determine whether each parameter was associated with clinical pathology. Tumor specimens were subjected to PD-L1 staining by immunohistochemistry. Analysis of whether there is a correlation between PD-L1 expression and ¹⁸F-FDG uptake parameters in CRC.

Results: PD-L1 expression level was significantly correlated with SUVmax, MTV3.0 and TLG3.0. Multivariate analysis showed that PD-L1 and TLG3.0 were independent predictors of poor DFS in patients with CRC (P=0.009; P=0.016), PD-L1 expression is closely related to the patient's lesion (TLG3.0) (P<0.01).

Conclusion: The results of this study indicate that there was a significant correlation between PD-L1 expression and TLG3.0 which suggested that FDG-PET could serve as a noninvasive tool to assess the tumor microenvironment and as a predictor of PD-L1 inhibitor activity to determine the optimal therapeutic strategy for CRC. High PD-L1 expression levels and high TLG3.0 are independent risk factors for DFS differences in CRC patients.

The Clinicopathological and Prognostic Value of PD-L1 Expression in Cholangiocarcinoma: A Meta-Analysis

Background: Recently, blockade of immune checkpoint has emerged as one of the most potential treatments for solid tumors. Programmed cell death ligand 1(PD-L1), a member of the B7 family of molecules, plays a crucial role in tumor immunobiology. However, the prognostic significance of PD-L1 in cholangiocarcinoma (CCA) patients remains controversial. This study aimed to inquire into the prognostic and clinicopathological significance of PD-L1 in CCA via a meta-analysis.

Methods: We searched PubMed, the Cochrane Library, Embase, Web of Science and Google Scholar up to April 2019, regardless of the region or language, for studies on the correlation between clinicopathology/prognosis and PD-L1 in patients with CCA. The pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated to investigate the prognostic significance of PD-L1 expression in cholangiocarcinoma. The odds ratios (ORs) were also determined to explore the association between PD-L1 expression and clinicopathological features.

Results: Our meta-analysis included 11 studies with 1,066 patients. The meta-analysis of these studies indicated a trend that high PD-L1 expression indicated a poor OS, but the result was not statistically significant (HR = 1.62, 95% CI [0.98–2.68], p = 0.063). For DFS, although the pooled result is not statistically significant, it trends toward being significant that high PD-L1 expression indicated improved DFS (HR = 0.80, 95% CI [0.62, 1.04], p = 0.092). In subgroup analyses, the results were not consistent across the subgroups that were divided based on the publication year (before 2018: HR = 1.92, 95% CI [1.34–2.75], p < 0.001; after 2018: HR = 1.42, 95% CI [0.70–2.89], p = 0.335). Moreover, PD-L1 expression in TCs significantly correlated with the AJCC TNM stage of CCA (OR = 0.52, 95% CI [0.27, 0.99], p = 0.09).

Conclusion: Our meta-analyses revealed that PD-L1 expressed in TCs was significantly correlated with the AJCC TNM stage of CCA. Based on the included studies, we found that PD-L1 indeed expressed in both TCs and ICs in CCA patients, raising the possibility of the use of anti-PD-1/PD-L1 therapy for CCA patients. In contrast, expression of PD-L1 did not seem to be associated with patient outcome in our study. The prognostic role of PD-L1 in CCA demands further investigation.

The association of PD-L1 expression with the efficacy of anti-PD-1/PD-L1 immunotherapy and survival of non-small cell lung cancer patients: a meta-analysis of randomized controlled trials

Background

We conducted a meta-analysis to evaluate the efficacy of anti-programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) monotherapy or immunotherapy combined with chemotherapy and further estimated the value of PD-L1 expression in predicting the response from anti-PD-1/PD-L1 treatments as monotherapy or in combination with chemotherapy.

Methods

Clinical trial data were searched from electronic databases, which evaluated PD-1/PD-L1 inhibitors in non-small cell lung cancer (NSCLC) and correlated with PD-L1 expression levels.

Results

Fifteen randomized-controlled trials involving 10,074 patients were identified. Comparing anti-PD-1/PD-L1 monotherapy to chemotherapy, the pooled HR for overall survival (OS) was 0.77 (95% CI: 0.69-0.85, P<0.00001). Subgroup analyses revealed that patients had longer OS at ≥1%, ≥5%, ≥10% and ≥50% PD-L1 expression levels. Patients with higher PD-L1 expression may get increased benefit from PD-1/PD-L1 inhibitors. Moreover, patients with PD-L1 ≥50% had an objective response rate (ORR) improvement from anti-PD-1/PD-L1 therapy (RR =1.87, 95% CI: 1.27-2.75, P=0.001), but no ORR benefits were observed in patients with PD-L1 expression <1% (RR =0.82, 95% CI: 0.56-1.22, P=0.33) or 1-49% (RR =0.80, 95% CI: 0.64-0.98, P=0.03). OS was significantly better in patients receiving second-or-third line treatments (P<0.00001) with PD-L1 ≥1%. The efficacy of PD-1 inhibitors was similar to that of PD-L1 inhibitors, with no significant difference (P=0.63, I²=0%). Furthermore, immunotherapy combined with chemotherapy had better OS (HR =0.64, 95% CI: 0.48-0.84, P=0.001) than chemotherapy alone. Subgroup analyses showed that patients benefited from the combined chemo-IO treatment in the first-line setting regardless of PD-L1 expression level.

Conclusions

PD-L1 expression may be a valuable predictor of the efficacy of anti-PD-1/PD-L1 monotherapy in certain NSCLC patients. However, the combination of chemotherapy plus immunotherapy significantly improved survival regardless of the PD-L1 expression level in the first-line treatment of NSCLC.

Changes in the tumor immune microenvironment in resected recurrent soft tissue sarcomas

Background

Little is known about how the tumor immune microenvironment (TIME) is modulated in recurrent soft tissue sarcomas (STS).

Methods

We evaluated CD8+ T cells, CD20+ B cells, Foxp3+ regulatory T cells (Tregs), and programmed cell death ligand 1 (PD-L1) in 72 paired pre-recurrent (1st resected) versus post-recurrent (2nd resected) STS by immunohistochemistry. Correlations with time to recurrence and prognosis were determined.

Results

We found that CD8, PD-L1, CD20, and Foxp3-positive cell counts changed in post-recurrent STS. PD-L1-positive tumor cell and lymphocyte counts increased in post-recurrent STS, whereas CD8+ T cell counts decreased. Changes in CD8+ T cell, CD20+ B cell, and PD-L1+ lymphocyte counts were associated with the time interval between surgeries. At admission, fewer CD8+ T cells were detected in patients with relapse than in newly diagnosed patients. Furthermore, post-recurrent STS with fewer CD8+ T cells compared with pre-recurrent STS were more likely to exhibit re-recurrence. The change in CD8+ T cells was positively associated with overall survival. In multivariate analyses, a decrease in CD8+ T cell counts in post-recurrent STS was an independent unfavorable prognostic factor.

Conclusions

The TIME differs between pre-recurrent STS and post-recurrent STS. The variation in CD8+ T cells and PD-L1 positivity may have essential roles during tumor relapse and provides a basis for determining therapeutic strategies.

Disorder of Coagulation-Fibrinolysis System: An Emerging Toxicity of Anti-PD-1/PD-L1 Monoclonal Antibodies

A disruption of immune checkpoints leads to imbalances in immune homeostasis, resulting in immune-related adverse events. Recent case studies have suggested the association between immune checkpoint inhibitors (ICIs) and the disorders of the coagulation-fibrinolysis system, implying that systemic immune activation may impact a balance between clotting and bleeding. However, little is known about the association of coagulation-fibrinolysis system disorder with the efficacy of ICIs. We retrospectively evaluated 83 lung cancer patients who received ICI at Kumamoto University Hospital. The association between clinical outcome and diseases associated with disorders of the coagulation-fibrinolysis system was assessed along with tumor PD-L1 expression. Among 83 NSCLC patients, total 10 patients (12%) developed diseases associated with the disorder of coagulation-fibrinolysis system. We found that disorders of the coagulation-fibrinolysis system occurred in patients with high PD-L1 expression and in the early period of ICI initiation. In addition, high tumor responses (72%) were observed, including two complete responses among these patients. Furthermore, we demonstrate T-cell activation strongly induces production of a primary initiator of coagulation, tissue factor in peripheral PD-L1^high monocytes, in vitro. This study suggests a previously unrecognized pivotal role for immune activation in triggering disorders of the coagulation-fibrinolysis system in cancer patients during treatment with ICI.

Comparative study of the PD-L1 expression and CD8+ tumor-infiltrating lymphocyte between surgically resected and matched re-biopsy specimens in recurrent non-small cell lung cancer

Introduction: Numerous studies conducted until date have reported that the chemotherapy regimen could affect the programmed cell death ligand 1 (PD-L1) expression status in patients with non-small cell lung cancer (NSCLC).

Materials and methods: A total of 36 NSCLC patients for whom both the surgically resected specimens of the primary tumors and re-biopsy specimens of the recurrent tumors were available were enrolled in this study. The PD-L1 expression status and tumor-infiltrating CD8-positive T lymphocytes (CD8+TILs) count were measured in paired samples by immunohistochemistry. The concordance rate in the tumor immune microenvironment (TIME) classification based on the PD-L1 expression status and CD8+TILs count was analyzed.

Results: While the PD-L1 expression levels were similar between the surgical and re-biopsy specimens in 77.8% of cases, in 16.7% of cases, the expression levels were higher in the re-biopsy specimens. When the analysis was confined to patients who had received platinum-based chemotherapy, the percentage increased to 42.9%. The TIME classification changed in the re-biopsy specimens as compared to the surgical specimens in one-third of the patients, especially in those who had received chemotherapy previously. The TIME classification in the re-biopsy specimens more closely resembled that in the metastatic lymph nodes as compared to that in the primary tumor.

Conclusion: In patients with recurrent NSCLC, especially those who have received chemotherapy previously, a recent re-biopsy sample is required to determine whether PD-1/PD-L1 inhibitors should be used for treatment or not.

Programmed cell death ligand 1 expression in cytologic and surgical non-small cell lung carcinoma specimens from a single institution: Association with clinicopathologic features and molecular alterations

BACKGROUND

Programmed cell death ligand 1 (PD-L1) expression by the 22C3 pharmDx companion assay has been validated in surgical specimens to support pembrolizumab treatment decisions for patients with non-small cell lung carcinoma (NSCLC). The aims of this study were 1) to assess the adequacy of cytologic specimens for PD-L1 evaluation and 2) to explore correlations of PD-L1 expression with clinicopathologic and molecular features.

METHODS

The study cohort included 100 cytology specimens (fluid [n = 28] and fine-needle aspiration [n = 72]) and 165 surgical specimens (biopsy [n = 138] and resection [n = 27]). The PD-L1 immunohistochemistry 22C3 assay and staining assessment were performed according to the manufacturer's instructions. PD-L1 expression was correlated with patients' demographics, pathologic characteristics, and molecular alterations.

RESULTS

One hundred forty-two specimens (53.6%) were positive for PD-L1 expression (≥1%). No statistically significant difference in PD-L1 expression was identified between cytologic (56.0%) and surgical specimens (52.1%). Seventy-four of 190 tested cases (38.9%) had genetic alterations. PD-L1 positivity was significantly more prevalent in cases with genetic alterations than in cases without genetic alterations. Furthermore, both PD-L1 positivity and high PD-L1 expression (≥50%) had statistically significant associations with Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations. PD-L1 expression had no significant association with histologic phenotypes or other clinicopathologic features.

CONCLUSIONS

The data indicate that cytologic specimens are comparable to surgical specimens for PD-L1 evaluation. The association of PD-L1 expression with KRAS mutations may have clinical relevance in selecting patients with NSCLC for immunotherapy.

The Risks and Benefits of Immune Checkpoint Blockade in Anti-AChR Antibody-Seropositive Non-Small Cell Lung Cancer Patients

Background: Anti-programmed cell death 1 (PD-1) monoclonal antibodies (Abs) unleash an immune response to cancer. However, a disruption of the immune checkpoint function by blocking PD-1/PD-ligand 1(PD-L1) signaling may trigger myasthenia gravis (MG) as a life-threatening immune-related adverse event. MG is a neuromuscular disease and is closely associated with being positive for anti-acetylcholine receptor (anti-AChR) Abs, which are high specific and diagnostic Abs for MG. Methods: A 72-year-old man was diagnosed with chemotherapy-refractory lung squamous cell carcinoma and nivolumab was selected as the third-line regimen. We describe the first report of an anti-AChR Ab-seropositive lung cancer patient achieving a durable complete response (CR) to an anti-PD-1 antibody therapy. To further explore this case, we performed multiplex immunofluorescence analysis on a pretreatment tumor. Results: The patient achieved a durable CR without developing MG. However, the levels of anti-AChR Abs were elevated during two years of anti-PD-1 antibody therapy. The tumor of the subclinical MG patient had high PD-L1 expression and an infiltrated–inflamed tumor immune microenvironment. Conclusions: This study suggests that immune checkpoint inhibitors can be safely used and provide the benefits for advanced cancer patients with immunologically ‘hot’ tumor even if anti-AChR Abs are positive. Although careful monitoring clinical manifestation in consultation with neurologist is needed, immune checkpoint inhibitors should be considered as a treatment option for asymptomatic anti-AChR Ab-seropositive cancer patients.

Clinical Importance of Epstein⁻Barr Virus-Associated Gastric Cancer

Epstein⁻Barr virus-associated gastric carcinoma (EBVaGC) is the most common malignancy caused by EBV infection. EBVaGC has definite histological characteristics similar to gastric carcinoma with lymphoid stroma. Clinically, EBVaGC has a significantly low frequency of lymph node metastasis compared with EBV-negative gastric cancer, resulting in a better prognosis. The Cancer Genome Atlas of gastric adenocarcinomas proposed a molecular classification divided into four molecular subtypes: (1) EBVaGC; (2) microsatellite instability; (3) chromosomal instability; and (4) genomically stable tumors. EBVaGC harbors a DNA methylation phenotype, PD-L1 and PD-L2 overexpression, and frequent alterations in the PIK3CA gene. We review clinical importance of EBVaGC and discuss novel therapeutic applications for EBVaGC.

Significant association of increased PD-L1 and PD-1 expression with nodal metastasis and a poor prognosis in oral squamous cell carcinoma

Programmed cell death ligand 1 (PD-L1) and its receptor PD-1 are immune checkpoint molecules that attenuate the immune response. Blockade of PD-L1 enhances the immune response in a variety of tumours and thus serves as an effective anti-cancer treatment. However, the biological and prognostic roles of PD-L1/PD-1 signalling in oral squamous cell carcinoma (OSCC) remain to be elucidated. The purpose of this study was to examine the correlation of PD-L1/PD-1 signalling with the prognosis of OSCC patients to assess its potential therapeutic relevance. The expression of PD-L1 and of PD-1 was determined immunohistochemically in 97 patients with OSCC and the association of this expression with clinicopathological characteristics was examined. Increased expression of PD-L1 was found in 64.9% of OSCC cases and increased expression of PD-1 was found in 61.9%. Univariate and multivariate analysis revealed that increased expression of PD-L1 and PD-1 positively correlated with cervical lymph node metastasis. The expression of CD25, an activated T-cell marker, was negatively correlated with the labelling index of PD-L1 and PD-1. Moreover, the patient group with PD-L1-positive and PD-1-positive expression showed a more unfavourable prognosis than the group with PD-L1-negative and PD-1-negative expression. These data suggest that increased PD-L1 and PD-1 expression is predictive of nodal metastasis and a poor prognosis and is possibly involved in cancer progression via attenuating the immune response.

The prognostic value of programmed cell death ligand 1 expression 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 PubMed, 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.

A novel histological examination with dynamic three-dimensional reconstruction from multiple immunohistochemically stained sections of a PD-L1-positive colon cancer

AIMS

Programmed cell death-ligand 1 (PD-L1) expression is observed in patients with microsatellite instability-high (MSI-H) colon cancer, which is susceptible to immune checkpoint blockade. The aim of this study was to investigate the interrelationship between PD-L1-positive cells and cytotoxic T cells, lymphatic vessels and vascular endothelium by using histological examination with the three-dimensional (3D) reconstruction of a PD-L1-positive colon cancer.

METHODS AND RESULTS

Serial sections of MSI-H colon cancer tissue were stained with haematoxylin and eosin (H&E) and Masson trichrome stains; immunohistochemical analysis of PD-L1, CD8, D2-40 and CD31 was performed. Several 3D models of MSI-H colon cancer were reconstructed with a 3D data visualisation system. Moreover, 18 serial sections were stained with PD-L1, cytokeratin AE1/AE3, CD45, CD31, CD68 and H&E in the same case to confirm that PD-L1 was expressed on tumour cells, CD31-positive cells and macrophages in the invasive frontal region. Notably, there was a peak in the expression of PD-L1 and CD31 in the invasive frontal region. D2-40-positive cells were abundant in the overall tumour stroma, and CD8-positive cells infiltrated the tumour parenchyma. PD-L1 was expressed on tumour cells in the parenchyma and other cells in the stroma. Additional staining of 18 consecutive sections revealed that the other cells were CD68-positive and CD45-positive macrophages and CD31-positive proliferating vascular endothelial cells.

CONCLUSIONS

We confirmed that PD-L1 was highly expressed in the invasive frontal region in 3D models of MSI-H colon cancer tissue. This method can be useful for accurately evaluating the localisation of immune checkpoint molecules.

Determination of PD-L1 expression in effusions from mesothelioma by immuno-cytochemical staining

BACKGROUND

Malignant mesothelioma (MM) is an aggressive, fatal tumor. Current therapeutic options only marginally improve survival. Programmed cell death ligand 1 (PD-L1) is a dominant mediator of immunosuppression, binding to programmed cell death 1 (PD-1). PD-L1 is up-regulated in cancer cells, and the PD-1/PD-L1 pathway plays a critical role in tumor immune evasion, thus providing a target for antitumor therapy. Further, a correlation between PD-L1 expression and prognosis has been reported. Studies performed on histological material have revealed expression of PD-L1 in MM, but no study has been performed on MM effusions thus far.

METHODS

PD-L1 expression was determined by a commercially available antibody (clone 28-8) in 74 formalin-fixed, paraffin-embedded cell blocks from body effusions obtained at diagnosis from patients with MM. The presence of MM cells was confirmed with CK5/6, calretinin, and EMA and the admixture of macrophages was assessed with CD68. Only cases containing more than 100 tumor cells were assessed. Membranous staining in tumor cells was considered positive. Survival time was calculated from the appearance of the first malignant effusion until death.

RESULTS

Reactivity was observed in 23 of 61 (38%) of cases and was classified as ≥1%-5% (n = 9 cases), >5%-10% (n = 4 cases), >10%-50% (n = 4 cases), and >50% (n = 6 cases) positive cells. Survival times did not differ significantly between patients with PD-L1-positive and PD-L1-negative tumors.

CONCLUSION

MM effusions are suitable for immune-cytochemical assessment of PD-L1 expression in malignant cells and the results are similar to those reported for histological specimens. Cancer Cytopathol 2017;125:908-17. © 2017 American Cancer Society.

Programmed cell death ligand 1 and tumor-infiltrating lymphocyte status in patients with renal cell carcinoma and sarcomatoid dedifferentiation

BACKGROUND

The immune profile of sarcomatoid renal cell carcinoma (sRCC), including the programmed cell death ligand 1 (PD-L1) and programmed cell death 1 (PD-1) status, has not been well characterized.

METHODS

An immunohistochemical digital analysis of PD-L1, PD-1, CD4, and CD8 was performed on nephrectomy specimens from 118 sRCC patients and 92 nonsarcomatoid clear cell renal cell carcinoma (ccRCC) patients. The clinical characteristics of the population were compared between sRCC and ccRCC. Overall survival was estimated, and comparisons were made between PD-L1-positive and PD-L1-negative groups as well as tumor-infiltrating lymphocyte (TIL)-high and TIL-low groups.

RESULTS

The PD-L1 H-score of sRCC (mean, 3.7; range, 0-192.1) was significantly higher than the score of grade 4 ccRCC (P = .001), and 41.3% of sRCC cases showed a PD-L1 H-score ≥ 10. The PD-1-positive cell density was significantly higher in sRCC versus ccRCC within the tumor and at the invasive front. The intratumoral CD8-positive cell density was significantly higher in sRCC versus ccRCC. Forty-one percent in the sarcomatoid component of sRCC and 8% in the epithelioid component of sRCC had an adaptive immune resistance phenotype (PD-L1-positive and TIL-positive), whereas only 1% in ccRCC had the type I phenotype.

CONCLUSIONS

sRCC showed higher PD-L1 expression and higher PD-1- and CD8-positive cell density than grade 4 ccRCC. The results indicate a notable immunosuppressive environment in sRCC. Despite advances in the treatment of advanced-stage renal cell carcinoma, sRCC still has a poor prognosis. This work describes highly immunosuppressive characteristics of sRCC in comparison with an appropriate ccRCC control. The results suggest PD-1/PD-L1 blockade therapy as a potential therapeutic approach for sRCC. Cancer 2017;123:4823-31. © 2017 American Cancer Society.

Clinicopathological and prognostic significance of programmed cell death ligand 1 (PD-L1) expression in patients with esophageal squamous cell carcinoma: a meta-analysis

BACKGROUND

The clinicopathological and prognostic significance of programmed cell death ligand 1 (PD-L1) expression in patients with esophageal squamous cell carcinoma (ESCC) remains controversial. To investigate this question, we conducted a meta-analysis.

METHODS

A comprehensive literature search of electronic databases (up to July 10, 2016) was performed for relevant studies using multiple search strategies. Correlation between PD-L1 expression and clinicopathological features/overall survival (OS) was analyzed.

RESULTS

A total of 1,350 ESCC patients from eight studies were included. The pooled odds ratios (ORs) indicated that none of the clinicopathological characteristics was correlated with PD-L1 expression, including gender [OR =0.84; 95% confidence interval (CI): 0.59-1.18; P=0.31], histological differentiation (OR =1.33; 95% CI: 0.95-1.85; P=0.09), tumor depth (OR =0.66; 95% CI: 0.33-1.35; P=0.26), status of lymph node metastasis (OR =0.67; 95% CI: 0.30-1.52; P=0.34), distal metastasis (OR =0.66; 95% CI: 0.40-1.09; P=0.10) and tumor node metastasis (TNM) stage (OR =0.93; 95% CI: 0.49-1.75; P=0.82). The combined hazard ratio (HR) for OS showed a trend that overexpression of PD-L1 might be associated with the survival outcome of ESCC, though the difference was not statistically significant (HR =1.65; 95% CI 0.95-2.85; P=0.07).

CONCLUSIONS

Based on the published studies, PD-L1 overexpression in ESCC was not associated with common clinicopathological characteristics. PD-L1 might be a poor prognostic biomarker for ESCC. Further large-scale research should be performed to reveal the precise clinicopathological and prognostic significance of PD-L1 in ESCC by unified testing standard.

Tumor-Infiltrating Lymphocytes in Triple Negative Breast Cancer: The Future of Immune Targeting

Triple negative breast cancer (TNBC) is a highly heterogeneous tumor. There is increasing evidence of the role of tumor lymphocytic immune infiltrates in this subtype of breast cancer. Robust levels of tumor infiltrating lymphocytes (TILs) have been associated with improved disease-free and overall survival rates in TNBC patients with and without any treatment. Recent efforts have been made to develop a standardized methodology for evaluating TILs. The presence of TILs in the breast tumor microenvironment can also predict responses not only to neoadjuvant but also to adjuvant chemotherapy treatments. High numbers of TILs correlate with increased pathological complete responses (pCR) in TNBC. TILs are prognostic and predictive of response to standard therapies; thus, the immune system appears to play an active role in a subgroup of breast cancer. There is an increasing interest in directly targeting the immune system as part of breast cancer therapy, mainly in patients with TNBC. New immune modulatory agents, including immune checkpoints inhibitors, have shown promising activity in a subgroup of metastatic TNBC. Increased programmed cell death protein 1 ligand (PD-L1) expression on the surface of TNBC provides the rationale for implementing therapeutic strategies targeting the PD-1/PD-L1 axis in TNBC. The programmed cell death protein 1 (PD-1) inhibitor pembrolizumab, and the PD-L1 inhibitor atezolizumab have shown promising results in clinical trials.

Clinicopathological and prognostic significance of programmed cell death ligand1 (PD-L1) expression in patients with non-small cell lung cancer: a meta-analysis

OBJECTIVE

Programmed cell death 1 (PD-1) and one of its ligands, PD-L1, are key immune checkpoint proteins. Evidences showed PD-L1 is an emerging biomarker for immunotherapy by anti-PD-1 and anti-PD-L1 antibody in non-small cell lung cancer (NSCLC). To investigate the association of PD-L1 protein expression with clinicopathological features and its impact on survival outcome, we conducted a meta-analysis.

METHODS

A comprehensive literature search of electronic databases (up to July 10, 2014) was performed. Correlation between PD-L1 expression and clinicopathological features and overall survival (OS) was analyzed by synthesizing the qualified data. Publication biases were examined.

RESULTS

A total of 1,550 NSCLC patients from 9 studies were included. The pooled odds ratios (ORs) indicated high PD-L1 expression was associated with poor tumor differentiation [OR =0.53, 95% confidence interval (CI): 0.39-0.72, P<0.0001]. Whereas, none of other clinicopathological characteristics [gender, smoking status, histological type, invasive depth of tumor, status of lymph node metastasis and tumor node metastasis (TNM) stage] were correlated with PD-L1 expression in current analysis. The combined hazard ratio (HR) for OS showed high expression of PD-L1 impaired the OS in NSCLC (HRpositive/negative =1.47, 95% CI: 1.19-1.83, P=0.0004).

CONCLUSIONS

Our meta-analysis indicated PD-L1 protein expression in NSCLC was not associated with common clinicopathological characteristics, except tumor differentiation. It was a poor prognostic biomarker for NSCLC. Further research should be performed to investigate the precise clinicopathological and prognostic significance of PD-L1 in NSCLC under uniform testing standard.

Clinicopathological and prognostic significance of programmed cell death ligand1 (PD-L1) expression in patients with non-small cell lung cancer: a meta-analysis

OBJECTIVE

Programmed cell death 1 (PD-1) and one of its ligands, PD-L1, are key immune checkpoint proteins. Evidences showed PD-L1 is an emerging biomarker for immunotherapy by anti-PD-1 and anti-PD-L1 antibody in non-small cell lung cancer (NSCLC). To investigate the association of PD-L1 protein expression with clinicopathological features and its impact on survival outcome, we conducted a meta-analysis.

METHODS

A comprehensive literature search of electronic databases (up to July 10, 2014) was performed. Correlation between PD-L1 expression and clinicopathological features and overall survival (OS) was analyzed by synthesizing the qualified data. Publication biases were examined.

RESULTS

A total of 1,550 NSCLC patients from 9 studies were included. The pooled odds ratios (ORs) indicated high PD-L1 expression was associated with poor tumor differentiation [OR =0.53, 95% confidence interval (CI): 0.39-0.72, P<0.0001]. Whereas, none of other clinicopathological characteristics [gender, smoking status, histological type, invasive depth of tumor, status of lymph node metastasis and tumor node metastasis (TNM) stage] were correlated with PD-L1 expression in current analysis. The combined hazard ratio (HR) for OS showed high expression of PD-L1 impaired the OS in NSCLC (HRpositive/negative =1.47, 95% CI: 1.19-1.83, P=0.0004).

CONCLUSIONS

Our meta-analysis indicated PD-L1 protein expression in NSCLC was not associated with common clinicopathological characteristics, except tumor differentiation. It was a poor prognostic biomarker for NSCLC. Further research should be performed to investigate the precise clinicopathological and prognostic significance of PD-L1 in NSCLC under uniform testing standard.