PD-L1 expression as poor prognostic factor in patients with non-squamous non-small cell lung cancer

Machine learning identifies prognostic subtypes of the tumor microenvironment of NSCLC

The tumor microenvironment (TME) plays a fundamental role in tumorigenesis, tumor progression, and anti-cancer immunity potential of emerging cancer therapeutics. Understanding inter-patient TME heterogeneity, however, remains a challenge to efficient drug development. This article applies recent advances in machine learning (ML) for survival analysis to a retrospective study of NSCLC patients who received definitive surgical resection and immune pathology following surgery. ML methods are compared for their effectiveness in identifying prognostic subtypes. Six survival models, including Cox regression and five survival machine learning methods, were calibrated and applied to predict survival for NSCLC patients based on PD-L1 expression, CD3 expression, and ten baseline patient characteristics. Prognostic subregions of the biomarker space are delineated for each method using synthetic patient data augmentation and compared between models for overall survival concordance. A total of 423 NSCLC patients (46% female; median age [inter quantile range]: 67 [60-73]) treated with definite surgical resection were included in the study. And 219 (52%) patients experienced events during the observation period consisting of a maximum follow-up of 10 years and median follow up 78 months. The random survival forest (RSF) achieved the highest predictive accuracy, with a C-index of 0.84. The resultant biomarker subtypes demonstrate that patients with high PD-L1 expression combined with low CD3 counts experience higher risk of death within five-years of surgical resection.

Association between PD-L1 and Ki-67 expression and clinicopathologic features in NSCLC patients

OBJECTIVE

To investigate the relationship between PD-L1, Ki-67 and the association between PD-L1, Ki-67, and clinicopathologic features and laboratory parameters in the peripheral blood of non-small cell lung cancer (NSCLC) patients.

METHODS

The clinical records of 213 NSCLC patients were retrospectively reviewed. The patients were divided into high or low expression groups by cut-off values of Ki-67 and PD-L1. Correlation of PD-L1 and Ki-67 expression were analyzed by linear regression analysis. The data were tested by Mann-Whitney test. Relationship of PD-L1 and Ki-67 was tested by chi-square test.

RESULTS

Linear regression analysis revealed a positive association between the expression of PD-L1 and Ki-67 (R2=0.26, P<0.001). The clinicopathologic features and laboratory parameters such as gender, smoking history, histological types, TNM stage, tumor size, ALB, and FIB were all significantly associated with PD-L1 and Ki-67 expression (all P<0.05).

CONCLUSIONS

The expression of PD-L1 and Ki-67 is related to some clinicopathologic features and inflammatory factors, which brings new sight for exploiting combination biomarkers and therapeutic strategies.

PD-L1 Expression is not a Predictive Factor for Recurrence in Resected Non-small Cell Lung Cancer

PURPOSE

Although targeting programmed death-1 (PD-1) and its ligand, programmed death-ligand 1 (PD-L1), is an established treatment modality for non-small cell lung cancer (NSCLC), the prognostic relevance of PD-L1 expression in NSCLC patients who undergo pulmonary resection is controversial.

METHODS

Two hundred thirty-seven NSCLC patients who underwent pulmonary resection were enrolled and the relationship between PD-L1 and various clinicopathological factors, as well as the prognostic relevance of PD-L1, was evaluated.

RESULTS

PD-L1 expression was significantly higher in male patients (p < 0.01), lymphatic invasion (p < 0.01), vascular invasion (p < 0.01), grade 3-4 differentiation (p < 0.01), squamous cell carcinoma (p < 0.01), and pathological stage > II (p < 0.01), but significantly lower in those who were epithelial growth factor receptor (EGFR) mutation negative (p < 0.01). Relapse-free survival was significantly worse in patients with PD-L1 expression (p = 0.04). Univariate analysis showed that male sex (p = 0.04), carcinoembryonic antigen expression (CEA) (p < 0.01), maximum standardized uptake value (p < 0.01), lymphatic invasion (p < 0.01), vascular invasion (p < 0.01), grade 3-4 differentiation (p < 0.01), lower lobe disease (p = 0.04), PD-L1 expression (p = 0.03), and pathological stage (p < 0.01) were significant risk factors of recurrence. In multivariate analysis, CEA expression (p = 0.01), lymphatic invasion (p = 0.04), and pathological stage (p < 0.01) were risk factors for recurrence, whereas PD-L1 expression was not a significant factor of recurrence (p = 0.62).

CONCLUSION

PD-L1 expression was not a risk factor of recurrence but tumor progression tended to increase PD-L1 expression.

TRIAL REGISTRATION

The Institutional Review Board of Kanazawa Medical University approved the protocol of this retrospective study (approval number: I392), and written informed consent was obtained from all patients.

Expression and Prognostic Significance of c-Myc, ALK, ROS1, BRAF, and PD-L1 Among Patients With Non-Small Cell Lung Cancer

Background:

Non-small cell lung cancer (NSCLC) remains a leading cause of cancer death worldwide, for which better knowledge in molecular prognostic factors is needed to improve clinical outcome. This study aimed to investigate the clinical significance of c-Myc, ALK, ROS1, BRAF, and PD-L1 in NSCLC patients.

Methods:

Formalin-fixed paraffin-embedded tissue specimens were obtained from 124 NSCLC patients. Of these, 66 matched specimens of normal respiratory epithelial and tumor tissue from patients with stages I-III, who underwent surgical resection, and 58 NSCLC specimens from stage IV patients were recruited into this analysis. Immunohistochemistry staining along with semiquantitative criteria were used to evaluate the expression of the interested proteins.

Results:

Of the 66 patients with stages I-III, positive expression of c-Myc was detected in 12 specimens (18.2%) of NSCLC tissue, whereas none of the normal respiratory epithelial tissue was found to have c-Myc expression (P < .001). Of the 66 NSCLC patients, 28 (43.8%) had PD-L1-positive staining on 1%-49% tumor cells and 7 (10.9%) patients expressed PD-L1 in ⩾50% tumor cells. One (2.3%) adenocarcinoma patient was found to have ROS1 rearrangement. Patients with no expression of c-Myc and PD-L1 (co-negative expression) tended to have a better prognosis than other subgroups.

Conclusions:

NSCLC tissue significantly expressed more c-Myc and PD-L1, compared with the matched normal respiratory epithelium, emphasizing the important role of these key drivers in tumorigenesis. Therapeutic approach to precisely inhibit the targetable molecular pathways should be considered on an individual patient basis to improve survival outcome.

Review of the recent clinical trials for PD-1/PD-L1 based lung cancer immunotherapy

INTRODUCTION

Lung cancer is known for its high mortality rate and prevalence in the world today. For decades, chemotherapy has been used as the main treatment for this cancer, but this has changed over time. Immune checkpoint inhibitors (ICIs) such as programmed death 1 and programmed death-ligand 1 (PD-1/PD-L1) blocking agents have been assessed in numerous clinical trials as single or combination therapy and have shown overall promising results. Nevertheless, various challenges have been encountered, which cast doubts over this method.

AREAS COVERED

We provide an introduction to the mechanisms underlying the PD-1/PD-L1 pathway. Then, we discuss the latest results from the most leading-edge studies evaluating PD-1/PD-L1 inhibitors in different lines of lung cancer therapy (some of which have gained FDA approval), potential biomarkers, and major challenges of ICI therapy.

EXPERT OPINION

Currently, the standard of care (SoC) for lung cancer consists mostly of chemotherapeutics. With further studies and ongoing trials evaluating novel ICI therapy, FDA has been approving specific ICI therapeutics, including PD-1/PD-L1 inhibitors, for particular types of lung cancer. However, for ICIs to play a key role in SoC, we need to overcome the major challenges of ICI therapy.

Gemcitabine Plus Nab-Paclitaxel Induces PD-L1 mRNA Expression in Plasma-Derived Microvesicles in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is a non-immunogenic tumor poorly responsive to immune checkpoint inhibitors. This study investigates the effect of 5-fluorouracil (5-FU), irinotecan, and oxaliplatin (FOLFIRINOX), and gemcitabine plus nab-paclitaxel (GEMnPAC) regimens on PD-L1 mRNA expression in plasma-derived microvesicles (MVs) in 50 PDAC patients. Plasma was collected before starting chemotherapy and after 3 months of treatment. mRNA was extracted from MVs, and PD-L1 expression was measured by digital droplet PCR. Twenty-eight patients were PD-L1 positive in MVs at baseline, of which 18 were in the GEMnPAC cohort and 10 in the FOLFIRINOX one. The amount of PD-L1 expression in MVs increased from baseline to 3 months of treatment in patients receiving GEMnPAC (median value 0.002 vs. 0.005; p = 0.01) compared to those treated with FOLFIRINOX (median 0.003 vs. 0.004; p = 0.97). The increase in PD-L1 mRNA expression in MVs was not related to tumor response (PR + SD: p = 0.08; PD: p = 0.28). Our findings demonstrate that GEMnPAC can increase PD-L1 mRNA expression in patient-derived circulating MVs, providing a rationale for testing the efficacy of this regimen in sequential or simultaneous combinations with immunotherapy in PDAC patients.

Scalp Metastasis as the First Presentation of an Underlying Aggressive Pancreatic Cancer

Pancreatic ductal adenocarcinoma, an extremely aggressive cancer, has high metastatic potential. Cutaneous metastasis is very uncommon, representing only <10% of all cases, presenting mostly around the umbilical region. Non-umbilical metastasis is even rarer, and the significance remains unknown. In this article, we describe a case of a 76-year-old gentleman who initially presented with an asymptomatic scalp lesion, which on biopsy revealed metastatic adenocarcinoma of pancreatic origin. Detailed workup revealed extremely high tumor burden with metastases involving muscles, subcutaneous tissues, bone, lung, spleen, liver, and colon. Cutaneous involvement in pancreatic cancer represents poor survival with widespread dissemination of the disease. The involvement of some sites and not others and the extreme degree of aggressiveness might reflect subgroups of this cancer with different molecular biology. Identifying these groups may have utility in determining prognosis and stratifying treatment for patients. This will hopefully translate into better diagnostic tests and therapies in the near future.

Programmed Death-Ligand 1 as a Regulator of Tumor Progression and Metastasis

Programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) immune checkpoint has long been implicated in modeling antitumor immunity; PD-1/PD-L1 axis inhibitors exert their antitumor effects by relieving PD-L1-mediated suppression on tumor-infiltrating T lymphocytes. However, recent studies have unveiled a distinct, tumor-intrinsic, potential role for PD-L1. In this review, we focus on tumor-intrinsic PD-L1 signaling and delve into preclinical evidence linking PD-L1 protein expression with features of epithelial-to-mesenchymal transition program, cancer stemness and known oncogenic pathways. We further summarize data from studies supporting the prognostic significance of PD-L1 in different tumor types. We show that PD-L1 may indeed have oncogenic potential and act as a regulator of tumor progression and metastasis.

Discovery of Pyrrole-imidazole Polyamides as PD-L1 Expression Inhibitors and Their Anticancer Activity via Immune and Nonimmune Pathways

In recent years, PD-1 immune checkpoint inhibitors based on monoclonal antibodies have revolutionized cancer therapy, but there still exist unresolved issues, such as the high cost, the relatively low response rates, and so on, compared with small-molecule drugs. Herein a type of pyrrole-imidazole (Py-Im) polyamide as a small-molecule DNA binder was designed and synthesized, which could competitively bind to the same double-stranded DNA stretch in the PD-L1 promoter region as the STAT3 binding site and thus downregulate PD-L1 expression. It was demonstrated that the Py-Im polyamides directly caused apoptosis in tumor cells and retarded cell migration in the absence of T cells through inhibiting the Akt/caspase-3 pathway. Also, in a coculture system, they enhanced the T-cell-mediated killing of tumor cells by the reversal of immune escape. Because such polyamides induced antitumor effects via both immune and nonimmune pathways, they could be further developed as promising PD-L1 gene-targeting antitumor drugs.

Serum-derived exosomal PD-L1 expression to predict anti-PD-1 response and in patients with non-small cell lung cancer

PD-L1 expression is the most useful predictive biomarker for immunotherapy efficacy on non-small cell lung cancer (NSCLC), and CD8+ tumor-infiltrating lymphocytes (CD8+ TILs) play an essential role in the clinical activity of immunotherapy. PD-L1 is found on the exosome’s surface, and PD-L1 expressing exosomes can inhibit antitumor immune responses. This study aimed to analyze tumor PD-L1 expression, serum exosomal PD-L1, and CD8+ TILs to investigate anti-PD-1 response and clinicopathological outcomes in NSCLC. One hundred twenty patients with stage I–III NSCLC were enrolled, and serum samples collected during the initial surgery were pooled. The Human CD274/PD-L1 ELISA kit was used to quantify the exosomal PD-L1. Exosomal PD-L1 levels were significantly correlated with tumor PD-L1 levels (p < 0.001) and the number of CD8+ TILs (p = 0.001). Patients with exosomal PD-L1 ≥ 166 pg/mL tended to have a worse RFS than those with < 166 pg/mL in all stage (p = 0.163) and stage I patients (p = 0.116). Seventeen patients exhibited postoperative recurrences and received anti-PD-1 treatment. The disease control rate of patients with exosomal PD-L1 ≥ 166 pg/mL was 100%. The measurement of serum exosomal PD-L1 as a quantitative factor with tumor PD-L1 status may help predict anti-PD-1 response and clinical outcomes in patients with NSCLC.

Comparison of programmed death-ligand 1 protein expression between primary and metastatic lesions in patients with lung cancer

Assessment of programmed cell death-ligand 1 (PD-L1) expression by immunohistochemistry (IHC) is the definite diagnostic test to guide treatment for patients with advanced-stage non-small cell lung cancer. Intratumoral heterogeneity and discrepancy of PD-L1 expression between primary and metastatic lesions may increase the risk of tumor misclassification. We performed a retrospective study of the Foundation Medicine, Inc clinical database on lung cancer cases that were evaluated for PD-L1 expression by IHC in the context of routine care. All cases were assessed with the Food and Drug Administration-approved 22C3 pharmDx assay and scoring system. 15,028 lung cancer cases, including 8285 primary tumors and 6743 unmatched metastatic lesions were analyzed. Metastatic lesions (mets) were more frequently high positive (tumor proportion score (TPS) ≥50%) for PD-L1 expression than primary lesions (33.8% vs 28.4%; OR, 1.28; 95% CI, 1.19 to 1.37; p<0.001). Higher levels in mets than primaries were seen in samples from lymph nodes, pleural fluid, soft tissue and adrenal gland but not in those from liver, brain and bone. Metastatic lesions of patients with non-squamous histology were more likely to have TPS ≥50% in comparison with primary (OR, 1.37; 95% CI, 1.27 to 1.49; p<0.001), but this was not the case for patients with squamous histology (OR, 0.89; 95% CI, 0.74 to 1.06; p=0.197). PD-L1 expression varies with respect to histologic subtype, sampling site and gender, but is generally higher in metastatic sites. This observation may affect future patient management and trial design.

miRNA Expression Characterizes Histological Subtypes and Metastasis in Penile Squamous Cell Carcinoma

Although microRNAs are described as promising biomarkers in many tumor types, little is known about their role in PSCC. Thus, we attempted to identify miRNAs involved in tumor development and metastasis in distinct histological subtypes considering the impact of HPV infection. In a first step, microarray analyses were performed on RNA from formalin-fixed, paraffin-embedded tumor (22), and normal (8) tissue samples. Microarray data were validated for selected miRNAs by qRT-PCR on an enlarged cohort, including 27 tumor and 18 normal tissues. We found 876 significantly differentially expressed miRNAs (p ≤ 0.01) between HPV-positive and HPV-negative tumor samples by microarray analysis. Although no significant differences were detected between normal and tumor tissue in the whole cohort, specific expression patterns occurred in distinct histological subtypes, such as HPV-negative usual PSCC (95 differentially expressed miRNAs, p ≤ 0.05) and HPV-positive basaloid/warty subtypes (247 differentially expressed miRNAs, p ≤ 0.05). Selected miRNAs were confirmed by qRT-PCR. Furthermore, microarray data revealed 118 miRNAs (p ≤ 0.01) that were significantly differentially expressed in metastatic versus non-metastatic usual PSCC. The lower expression levels for miR-137 and miR-328-3p in metastatic usual PSCC were validated by qRT-PCR. The results of this study confirmed that specific miRNAs could serve as potential diagnostic and prognostic markers in single PSCC subtypes and are associated with HPV-dependent pathways.

High PD-L1/IDO-2 and PD-L2/IDO-1 Co-Expression Levels Are Associated with Worse Overall Survival in Resected Non-Small Cell Lung Cancer Patients

Programmed death ligand 1 (PD-L1) expression is a predictive biomarker of the success of PD-1/PD-L1 inhibitor therapy for patients with advanced non-small cell lung cancer (NSCLC) but its role as a prognostic marker for early-stage resectable NSCLC remains unclear. We studied gene expression levels of immune-related genes PD-1, PD-L1, PD-L2, IDO-1, IDO-2 and INFγ in tumor tissue of surgically resected NSCLC and correlated the finding with clinicopathological features and patient outcomes. A total of 191 consecutive early-stage NSCLC patients who underwent curative pulmonary resection were studied. The mRNA expression levels of immune-related genes were evaluated by quantitative reverse transcription polymerase chain reaction (qRT-PCR) using RT² Profiler PCR Arrays (Qiagen). PD-1, PD-L2 and IDO-2 gene expression levels were significantly higher in patients with squamous histology (p = 0.001, p = 0.021 and p < 0.001; respectively). PD-1, PD-L1 and IDO-2 gene expression levels were significantly higher in patients with higher stage (p = 0.005, p = 0.048 and p = 0.002, respectively). The univariate analysis for recurrence-free survival (RFS) and overall survival (OS) showed that patients with higher levels of three-genes (PD-L1/PD-L2/INFγ) (hazard ratio (HR)) 1.90 (95% confidence interval (CI), 1.13–3.21), p = 0.015) were associated with a worse RFS, while patients with higher levels of both genes (PD-L1/IDO-2) or (PD-L2/IDO-1) were associated with a worse OS (HR 1.63 95% CI, 1.06–2.51, p = 0.024; HR 1.54 95% CI, 1.02–2.33, p = 0.04; respectively). The multivariate interaction model adjusted for histology and stage confirmed that higher levels of three genes (PD-L1/PD-L2/INFγ) were significantly associated with worse RFS (HR 1.98, p = 0.031) and higher levels of both genes (PD-L1/IDO-2) and (PD-L2/IDO-1) with worse OS (HR 1.98, p = 0.042, HR 1.92, p = 0.022). PD-L1/IDO-2 and PD-L2/IDO-1 co-expression high levels are independent negative prognostic factors for survival in early NSCLC. These features may have important implications for future immune-checkpoint therapeutic approaches.

Impact of Programmed Death Ligand 1 Expression in Advanced Non-Small-Cell Lung Cancer Patients, Treated by Chemotherapy (GFPC 06-2015 Study)

Background

Few data have been published on the clinical and histopathological characteristics of advanced non-small–cell lung cancer (NSCLC) patients with high PD-L1 expression versus intermediate or none and the prognostic value of PD-L1 expression for patients treated with chemotherapy is unknown. This study was undertaken to prospectively assess the prognostic value of tumor-cell (TC) and immune-cell (IC) PD-L1 expressions for advanced NSCLC patients.

Methods

It was a prospective, multicenter study on advanced NSCLC patients, with performance status 0/1, scheduled, consecutively, to receive first-line platin-based chemotherapy. PD-L1 expression was determined immunochemically (Dako Autostainer and monoclonal antibody 22C3) and its impact on progression-free survival (PFS) and overall survival (OS) assessed.

Results

Among 198 patients screened in 19 centers, 140 were included median age: 66.5 ± 10 years; 76.4% men; 79.3% Caucasians; 10.7% nonsmokers; 63.6% adenocarcinomas; <1%, 1–50% and ≥50% TC PD-L1–expression rates were 47.1%, 25.7% and 27.2% of patients, respectively; respective null, intermediate and high rates on ICs were 35.7%, 38.6% and 25.7%. Second- and third-line chemotherapies were administered to 58.6% and 26.4% of the patients, respectively. None received immunotherapy. First-, second- and third-line median (95% CI) PFS lasted 4.6 (3.6–5.2), 3.7 (2.3–4.7) and 2.2 (1.5–4.3) months, respectively; median OS was 16.9 (11.4–19.9) months. No significant PFS and OS differences were observed according to TC or IC PD-L1 expression.

Conclusion

According to the results of this prospective, multicenter study, neither TC nor IC PD-L1 expression appears to be prognostic for chemotherapy-managed advanced NSCLC patients.

Prognostic value of PD-L1 expression in patients with unresectable stage III non-small cell lung cancer treated with chemoradiotherapy

Background

Expression of PD-L1 is the most investigated predictor of benefit from immune checkpoint blockade in advanced NSCLC but little is known about the association of PD-L1 expression and clinicopathological parameters of patients with unresectable stage III NSCLC.

Methods

National registry data was searched for medical records of consecutive inoperable stage III NSCLC patients treated with ChT and RT from January 2012 to December 2017. Totally 249 patients were identified that met inclusion criteria and of those 117 patients had sufficient tissue for PD-L1 immunohistochemical staining.

Results

Eighty patients (68.4%) expressed PD-L1 of ≥ 1% and 29.9% of more than 50%. Median PFS was 15.9 months in PD-L1 negative patients and 16.1 months in patients with PD-L1 expression ≥ 1% (p = 0.696). Median OS in PD-L1 negative patients was 29.9 months compared to 28.5 months in patients with PD-L1 expression ≥ % (p = 0.888). There was no difference in median OS in patients with high PD-L1 expression (≥ 50%) with 29.8 months compared to 29.9 months in those with low (1–49%) or no PD-L1 expression (p = 0.694). We found that patients who received a total dose of 60 Gy or more had significantly better median OS (32 months vs. 17.5 months, p < 0.001) as well as patients with PS 0 (33.2 vs. 20.3 months, p = 0.005).

Conclusions

In our patients PD-L1 expression had no prognostic value regarding PFS and OS. Patients with good performance status and those who received a total radiation dose of more than 60 Gy had significantly better mOS.

Biphasic prognostic significance of PD-L1 expression status in patients with early- and locally advanced-stage non-small cell lung cancer

Programmed cell death-ligand 1 (PD-L1) expression on tumor cells is induced by interferon-gamma, suggesting the induction of an anti-tumor immune response. In turn, binding of PD-L1 to programmed cell death 1 (PD-1) triggers an immune checkpoint pathway that contributes to tumor growth. Though it remains to be elucidated, the clinical significance of PD-L1 expression might vary with tumor progression in non-small-cell lung cancer (NSCLC). Immunohistochemical analysis of PD-L1 was done in tumor specimens from patients who underwent radical surgery for stage I-IIIA NSCLC (n = 228). Tumor PD-L1 expression intensity was semi-quantitatively scored and its correlation with various clinicopathological features and postoperative relapse-free survival (RFS) was assessed relative to pathological stage. In stage I, postoperative RFS was significantly prolonged in patients with a high PD-L1 score compared with a low PD-L1 score, exhibiting 5-year relapse-free probabilities of 94.1% and 75.1%, respectively (P = 0.031). A multivariate analysis revealed that a high PD-L1 score was a prognostic factor of longer postoperative RFS (hazard ratio: 0.111, P = 0.033). Conversely, in stages II and IIIA, patients with a high PD-L1 score tended to suffer from postoperative tumor recurrence. In early-stage NSCLC, high tumor PD-L1 expression status represents a biomarker to predict good prognosis after radical surgery and may reflect the induction of an antitumor immune response. However, in locally advanced stage NSCLC, tumor PD-L1 expression status may reflect the execution of an immune checkpoint pathway and predicts the incidence of postoperative tumor recurrence.

Clinicopathological factors associated with tumor-infiltrating lymphocyte reactivity in breast cancer

BACKGROUND

The clinical significance of adoptive tumor-infiltrating lymphocyte (TIL) therapy has been demonstrated in many clinical trials. We analyzed the in vitro reactivity of cultured TILs against autologous breast cancer cells.

METHODS

TILs and cancer cells were cultured from 31 breast tumor tissues. Reactivity of TILs against cancer cells was determined by measuring secreted interferon-gamma. Expression levels of epithelial markers, major histocompatibility complex molecules, and programmed death-ligand 1 (PD-L1) in cancer cells, and T cell markers (memory, T cell activation and exhaustion, and regulatory T cell markers) in expanded TILs were analyzed and compared between the reactive and non-reactive groups.

RESULTS

In seven cases, TILs showed reactivity to autologous cancer cells. Six of these cases were associated with triple-negative breast cancer (TNBC). All reactive TNBCs were derived from surgical specimens after neoadjuvant chemotherapy (NAC). Higher expression of Ki67 in tumor tissues and lower expression of PD-L1 in cultured cancer cells were associated with reactivity. Proliferation of reactive TILs was high. High proportions of T cells and PD-1⁺CD4⁺ and PD1⁺CD8⁺ T cells were associated with reactivity in TNBC cases, while other activation or exhaustion markers were not.

CONCLUSION

TILs from approximately half the TNBC cases with NAC showed reactivity against autologous cancer cells. The proportion of PD-1⁺ T cells was higher in the reactive group. Adoptive TIL therapy combined with PD-1 inhibitors might be promising for TNBC patients with residual tumors after NAC.

ACT001 reduces the expression of PD-L1 by inhibiting the phosphorylation of STAT3 in glioblastoma

ACT001, which is derived from an ancient anti-inflammatory drug, has been shown to cross the blood-brain barrier in preclinical studies and has demonstrated anti-glioblastoma (GBM) activity in clinical trials. However, its pharmacological potential for anti-GBM immune response modulation remains unclear. The chemical structure of ACT001 indicates that it may bind to STAT3 and thus modulate antitumor immune response. Methods: Bioinformatics and immunohistochemistry (IHC) were used to assess STAT3 and PD-L1 expression in gliomas. Western blotting, RT-PCR and immunofluorescence were used to detect PD-L1 and p-STAT3 expression in glioma cells exposed to ACT001. Chromatin immunoprecipitation, an ACT001-Biotin probe, and a dual-luciferase reporter assay were used to detect direct modulation. The in vivo efficacy of ACT001 was evaluated in GL261 murine glioma model. Survival analyses were conducted using the log-rank (Mantel-Cox) test. Results: Bioinformatic analysis of 1,837 samples from 4 public glioma datasets showed that STAT3 mRNA expression was correlated with the degree of malignancy and therapeutic resistance and that STAT3 mRNA expression was related to immunosuppression, leukocyte infiltration, and PD-L1 expression. IHC staining of 53 tissue samples confirmed that relatively high phosphorylated STAT3 and PD-L1 protein expression was associated with a relatively advanced World Health Organization (WHO) glioma grade. Next, we confirmed that ACT001 treatment reduced PD-L1 expression and STAT3 phosphorylation. An ACT001-biotin probe was used to verify that ACT001 bound to STAT3. We also demonstrated that STAT3 bound to the PD-L1 promoter. The inhibition of PD-L1 expression and STAT3 phosphorylation by ACT001 could be rescued by STAT3 overexpression. Additionally, ACT001 inhibited GBM growth and decreased PD-L1 expression in vivo. The expression of the M2 markers CD206 and CD163 was decreased, while that of the antitumor immune markers iNOS and IFNγ was increased by ACT001 in vivo. Conclusion: Our results demonstrate that STAT3 plays a key role in immunosuppression of glioma and is inhibited by ACT001. ACT001 inhibits PD-L1 transcription and modulates anti-tumor immune response in glioma bearing mice. These findings will help us to understand the mechanism of ACT001 in GBM therapy.

The progress and confusion of anti-PD1/PD-L1 immunotherapy for patients with advanced non-small cell lung cancer

Recently, immunotherapy has evolved into a true treatment modality with the approval of PD-1 and PD-L1 inhibitors as the standard care for first-line treatment in patients with non-small cell lung cancer (NSCLC). Until now, for patients with advanced NSCLC, treatment of targeting immune checkpoints reveals a promising survival benefit, and some patients even get long term survive, which creates a paradigm shift in NSCLC treatment. However, many issues or problems are also appearing in clinical practice, such as the lower overall efficacy rate (20-40%), treatment modes, populations choice of immunotherapy, drug resistance, and safety, etc. Thus, in this review, we will mainly summarize and discuss the recent development and confusion of PD-1/PD-L1 inhibitors for advanced NSCLC patients based on current clinical studies.

Prognostic value of PD-L1 expression on tumor cells combined with CD8+ TIL density in patients with locally advanced non-small cell lung cancer treated with concurrent chemoradiotherapy

Background/aim

mmune checkpoint inhibition (CPI) has an increasing impact in the multimodal treatment of locally advanced non-small cell lung cancer (LA-NSCLC). Increasing evidence suggests treatment outcome depending on tumor cell PD-L1 expression. The purpose of this retrospective study was to investigate the prognostic value of PD-L1 expression on tumor cells in combination with CD8+ tumor stroma-infiltrating lymphocyte (TIL) density in inoperable LA-NSCLC treated with concurrent chemoradiotherapy (CRT).

Patients and method

We retrospectively assessed clinical characteristics and initial tumor biopsy samples of 31 inoperable LA-NSCLC patients treated with concurrent CRT. Prognostic impact of tumor cell PD-L1 expression (0% versus ≥1%) and CD8+ TIL density (0–40% vs. 41–100%) for local control, progression-free (PFS) and overall survival (OS) as well as correlations with clinicopathological features were evaluated.

Results

Median OS was 14 months (range: 3–167 months). The OS rates at 1- and 2 years were 68 and 20%. Local control of the entire cohort at 1 and 2 years were 74 and 61%. Median PFS, 1-year and 2-year PFS were 13 ± 1.4 months, 58 and 19%. PD-L1 expression < 1% on tumor cells was associated with improved OS, PFS and local control in patients treated with concurrent CRT. Univariate analysis showed a trend towards improved OS and local control in patients with low CD8+ TIL density. Evaluation of Tumor Immunity in the MicroEnvironment (TIME) appears to be an independent prognostic factor for local control, PFS and OS. The longest and shortest OS were achieved in patients with type I (PD-L1^neg/CD8^low) and type IV (PD-L1^pos/CD8^low) tumors (median OS: 57 ± 37 vs. 10 ± 5 months, p = 0.05), respectively.

Conclusion

Assessment of PD-L1 expression on tumor cells in combination with CD8+ TIL density can be a predictive biomarker in patients with inoperable LA-NSCLC treated with concurrent CRT.

Prognostic impacts of the combined positive score and the tumor proportion score for programmed death ligand-1 expression by double immunohistochemical staining in patients with advanced gastric cancer

BACKGROUND

The tumor proportion score (TPS) and combined positive score (CPS) have been developed to assess programmed death ligand 1 (PD-L1) expression in gastric cancer (GC). This study aimed to elucidate the role of TPS and CPS as prognostic biomarkers.

METHODS

A total of 191 patients with GC who received curative gastrectomy were retrospectively enrolled. Double immunohistochemistry of PD-L1 and ionized calcium binding adaptor molecule 1 was performed to clearly distinguish PD-L1 expression between tumor cells and macrophages. Survival analysis for PD-L1 expression by TPS and CPS was performed.

RESULTS

PD-L1 positivity was detected in 39 patients (20.4%) by TPS and in 137 patients (71.7%) by CPS. Patients with PD-L1 positivity by CPS experienced significantly shorter overall survival (OS) (P < 0.01) and relapse-free survival (RFS) (P = 0.01) than the other patients. In contrast, patients with either PD-L1 status by the TPS showed similar OS and RFS times. Multivariate Cox regression analysis for OS and RFS demonstrated that PD-L1 positivity by CPS was a significant independent factor for poor OS (hazard ratio [HR] 2.27, 95% confidence interval [CI] 1.27-4.37, P < 0.01) and RFS (HR 1.81, 95% CI 1.07-3.22, P = 0.03).

CONCLUSIONS

CPS was shown to be a more useful assessment method of determining PD-L1 expression than TPS as a prognostic biomarker. This suggests that the total number of PD-L1-expressing cells, including tumor and immune cells, is a more sensitive prognostic biomarker than the number of PD-L1-expressing tumor cells in GC.

Expression and clinical significance of PD-L1 and c-Myc in non-small cell lung cancer

BACKGROUND

It is known that there are insufficient prognostic factors for non-small cell lung cancer (NSCLC). It was reported that PD-L1 was a prognostic factor for NSCLC,and c-Myc regulated the expression of PD-L1. Herein, we investigated c-Myc and PD-L1 expression and their association with overall survival (OS) in NSCLC.

METHODS

Formalin-fixed paraffin-embedded specimens were obtained from 128 patients with surgically resected primary NSCLC. Immunohistochemistry was used to assess the expression of PD-L1 and c-Myc in this study. Pearson's Chi squared test or Fisher's exact test was used to analyze the correlation of the expression of PD-L1 and c-Myc with clinicopathologic features. The relationship between OS and the expression of PD-L1 and c-Myc was evaluated by the Kaplan-Meier method and Cox proportional hazards model, respectively.

RESULTS

Positive expression of PD-L1 was detected in 59 patients (46.1%). Patients with negative expression of PD-L1 had remarkably longer OS than those with positive expression of PD-L1. The positive expression rate of c-Myc in NSCLC accounted for 58.6% (75/128) and its expression was significantly more frequent in males (p = 0.002) and patients with lymph node metastasis (p = 0.029). PD-L1 expression was positively correlated with c-Myc expression (r = 0.459, p < 0.001). The PD-L1 and c-Myc double-positive group had a worse prognosis than other subgroups (p < 0.05), and the PD-L1 and c-Myc double-negative group had a better OS than other subgroups (p < 0.05).

CONCLUSION

Conjoint analysis of the expression of PD-L1 and c-Myc was a better prognostic approach for NSCLC patients.

Dynamic changes in PD-L1 expression and CD8+ T cell infiltration in non-small cell lung cancer following chemoradiation therapy

OBJECTIVES

The treatment for stage III non-small cell lung cancer (NSCLC) is quite variable because stage III NSCLC is a heterogenous disease. Programmed death ligand 1 (PD-L1) and CD8⁺ tumor infiltrating lymphocytes (TILs) are thought to be related to treatment outcome in many tumors. To improve treatment outcome in stage III NSCLC, it is necessary to obtain data on PD-L1 expression and CD8⁺ TIL counts following CCRT and their relationship to treatment outcome.

MATERIALS AND METHODS

We retrospectively enrolled 43 patients with stage III NSCLC treated with neoadjuvant CCRT followed by surgery at Yonsei Cancer Center Severance Hospital in Korea between June 2008 and October 2010. PD-L1 level and CD8⁺ TIL numbers in tumors following CCRT were analyzed by immunohistochemistry, and their association with patient survival was evaluated with Kaplan-Meier method.

RESULTS

More than half patients (52%) showed up- or downregulation of PD-L1 expression, and most patients (81%) showed change in CD8⁺ TIL counts by CCRT. Patients with PD-L1 expression following CCRT tended to have shorter recurrence free survival (RFS) (P = 0.182) or overall survival (OS) (P = 0.215) compared to the ones without PD-L1 expression. In the survival analysis with pre-CCRT specimens, neither RFS nor OS showed statistically significant differences. Patients with increased CD8⁺ TIL counts following CCRT regardless of pathological response strongly showed longer OS (median: not reached vs. 14.2 months for others; P = 0.017).

CONCLUSIONS

CCRT dynamically alters PD-L1 expression and CD8⁺ TIL numbers in stage III NSCLC. Our data provide a rationale for combining CCRT and immunotherapy for the treatment of potentially resectable NSCLC.

The clinicopathological and prognostic significance of PD-L1 expression assessed by immunohistochemistry in lung cancer: a meta-analysis of 50 studies with 11,383 patients

Background

We conducted a meta-analysis to systematically evaluate the relationship between programmed death-ligand 1 (PD-L1) expression and survival in patients with lung cancer.

Methods

The electronic databases PubMed, Embase, Cochrane, and Web of Science were searched up to January 2^nd, 2018, for articles relating to PD-L1 expression detected by immunohistochemistry (IHC) and lung cancer patient prognosis.

Results

Fifty studies including 11,383 patients published between 2011 and 2017 were enrolled in this meta-analysis. The pooled hazard ratios (HRs) and 95% confidence intervals (CIs) suggested that PD-L1 IHC expression was related to poor overall survival (OS) (HR =1.45, 95% CI: 1.24-1.68). In subgroup analysis categorized according to sample type, cut-off value, ethnicity and TNM stage, the pooled results demonstrated inferior survival in the PD-L1 positive group when the PD-L1 expression was detected by resection specimens (P=0.000), 5% was taken as the cutoff value (P=0.000), the patients were in early stage (I-III) (P=0.000), and the geographic setting of the study was in Asia (P=0.000). Besides, patients with high PD-L1 expression had shorter OS in NSCLC (P=0.000), ADC (P=0.000), SCC (P=0.353) and LELC (P=0.810), while no significant difference was observed in SCLC (P=0.000). The pooled odds ratios (ORs) suggested that PD-L1 expression was associated with male (P<0.001), smoker (P<0.001), poor tumor differentiation (P=0.014), large tumor size (P=0.132), positive lymph nodal metastasis (P=0.002), EGFR wild-type status (P<0.001) and KRAS mutations (P=0.393). However, age (P=0.15) and ALK rearrangements (P=0.567) had no bearing on PD-L1 expression.

Conclusions

PD-L1 expression that is associated with several clinicopathological feactures may serve as a poor prognostic biomarker for patients with lung cancer.

Plasma soluble programmed death ligand 1 levels predict clinical response in peripheral T-cell lymphomas

Immune checkpoints, including PD-1/PD-L1, play an important role in immunosuppression in various malignancies. Elevated levels of soluble programmed death ligand 1 (sPD-L1) are associated with worse prognosis in multiple myeloma and diffuse large B cell lymphoma. Herein, the purpose of this study is to investigate the relationships between plasma sPD-L1 levels and clinical response in peripheral T-cell lymphoma (PTCL) patients. A total of 37 PTCL patients and 20 healthy volunteers were enrolled. Peripheral blood from patients was collected prior to systemic therapy. Plasma levels of sPD-L1 and IFN-γ were measured by enzyme-linked immunosorbent assay (ELISA). PD-L1 expression in tissues was detected by immunohistochemistry (IHC). Clinical response for patients was evaluated. ONCOMINE database analyses showed that PD-L1 mRNA expression was significantly upregulated in PTCLs. The median sPD-L1 level was 0.729 ng/mL for 20 healthy volunteers and 1.696 ng/mL for 37 PTCL patients which was significantly higher than that in healthy volunteers (0.000). The sPD-L1 level was positively correlated with IFN-γ level (0.000, r = 0.849) and was also positively associated with clinical staging (0.045), LDH level (0.003), and β2-MG level (0.045). Patients with high sPD-L1 level had lower overall response rate than those with low sPD-L1 level (88.9% vs 50.0%, 0.022) and tended to have poorer PFS and OS. PD-L1 expression in tissues matched very well with the sPD-L1 level in PTCL patients. In conclusion, PTCL patients had higher sPD-L1 level compared with healthy volunteers. High sPD-L1 level was correlated with worse clinical response, suggesting that sPD-L1 level was an underlying plasma biomarker to predict the prognosis for PTCL patients.

Diagnostic and therapeutic applications of miRNA-based strategies to cancer immunotherapy

Cancer immunotherapy has shown impressive clinical results in the last decade, improving both solid and hematologic cancer patients' overall survival. Nevertheless, most of the molecular aspects underlying the response to this approach are still under investigation. miRNAs in particular have been described as regulators of a plethora of different immunologic processes and thus have the potential to be key in the future developments of immunotherapy. In this review, we summarize and discuss the emerging role of miRNAs in the diagnosis and therapeutics of the four principal cancer immunotherapy approaches: immune checkpoint blockade, adoptive cell therapy, cancer vaccines, and cytokine therapy. In particular, this review is focused on potential roles for miRNAs to be adjuvants in soluble factor- and cell-based therapies, with the aim of helping to increase specificity and decrease toxicity, and on the potential for rationally identified miRNA-based diagnostic approaches to aid in precision clinical immunooncology.

PD-L1 Expression in Non-Small-Cell Lung Cancer Including Various Adenocarcinoma Subtypes

PURPOSE

Knowledge regarding programmed death-ligand 1 (PD-L1) expression in lung cancer is limited. We aim to clarify PD-L1-positive expression in non-small-cell lung cancer (NSCLC), including adenocarcinoma subtypes.

METHODS

In all, 90 NSCLC specimens containing various adenocarcinoma subtypes, in addition to squamous cell carcinoma and large-cell carcinoma were selected. PD-L1 was immunohistochemically stained by murine monoclonal antibody clone 22C3.

RESULTS

When PD-L1-positive expression was defined by tumor proportion score (TPS) ≥1%, the positive cases were 0/11 in adenocarcinoma in situ, 0/12 in minimally invasive adenocarcinoma, 1/10 in lepidic predominant adenocarcinoma, 1/13 in papillary predominant adenocarcinoma, 8/14 in acinar predominant adenocarcinoma, 6/11 in solid predominant adenocarcinoma, 0/3 in micropapillary predominant adenocarcinoma, 0/4 in invasive mucinous adenocarcinoma, 4/9 in squamous cell carcinoma, and 2/3 in large-cell carcinoma. PD-L1 positivity was higher in males, smokers, advanced pathologic stages, positive vessel invasion, and positive lymphatic invasion. Postoperative survival analysis revealed that PD-L1-positive expression was a significantly worse prognostic factor in univariate analysis for recurrence-free survival (RFS).

CONCLUSION

PD-L1-positive tumors were frequent in acinar predominant adenocarcinoma and solid predominant adenocarcinoma than other adenocarcinoma subtypes. PD-L1 expression seemed to increase according to pathologic tumor progression, suggesting a worse postoperative prognosis in NSCLC patients.

Role of PD-L1 Expression in Non-Small Cell Lung Cancer and Their Prognostic Significance according to Clinicopathological Factors and Diagnostic Markers

Background: The latest immunotherapy, used in the treatment of non-small cell lung cancer (NSCLC), uses monoclonal antibodies directed against programmed death ligand 1 (PD-L1) to inhibit its interaction with the PD-1 receptor. Elevated levels of PD-L1 expression were observed on NSCLC cells. The association between PD-L1 expression and clinicopathological features is still unclear. Therefore, we examined this relationship and also compare PD-L1 expression levels with Ki-67, p63 and TTF-1. Methods: 866 samples of NSCLCs were used to prepare tissue microarrays (TMAs) on which immunohistochemical (IHC) reactions were performed. Changes in the level of CD274 (PD-L1) gene expression in 62 NSCLC tumors were tested in relation to 14 normal lung tissues by real-time PCR reactions (RT-PCR). Results: PD-L1 expression was observed in 32.6% of NSCLCs. PD-L1 expression was increased in higher malignancy grades (G) (p < 0.0001) and in higher lymph node status (pN) (p = 0.0428). The patients with low PD-L1 expression had longer overall survival compared to the group with high expression (p = 0.0332) in adenocarcinoma (AC) only. Conclusions: PD-L1 expression seems to be associated with increased tumor proliferation and aggressiveness as well as shorter patient survival in NSCLC, predominantly in the AC group.

Programmed death ligand 1 expression in early stage, resectable non-small cell lung cancer

INTRODUCTION

For several years non-small cell lung cancer (NSCLC) has been considered non-immunogenic. Recent advances in antitumor immunity brought to the discovery of checkpoints that modulate immune response against cancer. One of them is programmed death receptor 1 (PD-1) and its ligand (PD-L1). Although PD-L1 expression seems predictive of response to anti-PD-1/PD-L1 agents, its prognostic value is unclear. In this study we investigated the prognostic value of PD-L1 expression and its correlation with clinical-pathological characteristics in a cohort of surgically resected NSCLC.

MATERIAL AND METHODS

PD-L1 expression was evaluated in 289 surgically resected NSCLC samples by immunohistochemistry. Our cohort included patients not exposed to adjuvant chemotherapy. PD-L1 status was defined as: 1) PD-L1 high (tumor proportion score, TPS≥50%), PD-L1 low (TPS 1-49%), PD-L1 negative (TPS<1%); 2) PD-L1 positive (TPS≥50%) and negative (TPS<50%); 3) as a continuous variable.

RESULTS

Patients were mostly males (79%), former or current smokers (81%), with a median age of 67 years, non-squamous histology (67.5%) and high-grade tumors (55%). PD-L1 tumors were 18.7%. There was no significant association with sex, age, smoking status and histology. A strong correlation between high PD-L1 expression and tumor grade was detected. The difference in median OS in the different groups of patients was not statistically significant.

CONCLUSION

PD-L1 is not prognostic in surgically resected NSCLC. The association with tumor differentiation suggests that grading could represent an easy-to-assess tool for selecting subjects potentially sensitive to immunotherapy warranting further investigations.

The clinicopathological and prognostic value of programmed death-ligand 1 in colorectal cancer: a meta-analysis

INTRODUCTION

Programmed death-ligand 1 (PD-L1) is reportedly expressed in colorectal tumors. However, the prognostic role of PD-L1 in colorectal cancer (CRC) remains controversial. Therefore, we performed a meta-analysis to investigate the clinicopathological and prognostic impact of PD-L1 in CRC.

METHODS

A comprehensive search in PubMed, Embase, the Cochrane Library, Web of Science and the ClinicalTrials.gov for publications about PD-L1 expression in colorectal cancer was done. The correlation between PD-L1 expression and clinicopathological features or survival outcomes was analyzed by odds ratios (OR) or hazard ratios (HR), at 95% confidence intervals (CI).

RESULTS

The results show that the pooled HR of (1.34, 95% CI 1.02-1.65, p = 0.01) indicated the association of PD-L1 expression with overall survival (OS) in CRC patients. Meanwhile, the expression of PD-L1 was positively correlated with the lymph node metastasis (OR: 0.70, 95% CI 0.51-0.95, p = 0.00), gender (OR: 0.86, 95% CI 0.76-0.98, p = 0.05) and tumor location (OR: 1.39, 95% CI 1.14-1.71, p = 0.12).

CONCLUSIONS

These results suggest that high expression of PD-L1 is associated with low OS in CRC. High PD-L1 expression may act as a negative factor for patients with CRC and help to identify patients suitable for anticancer therapy.

PD-L1 Expression in Men with Penile Cancer and its Association with Clinical Outcomes

BACKGROUND

It has been hypothesized that PD-L1 expression in tumor cells and tumor-infiltrating immune (TII) cells may contribute to tumor progression by inhibiting antitumor immunity.

OBJECTIVE

To investigate the association between PD-L1 expression in tumor cells and TII cells and clinical outcomes in penile cancer.

DESIGN, SETTING, AND PARTICIPANTS

A cohort of 222 men treated for penile squamous cell carcinoma (SqCC) at Örebro University Hospital between 1984 and 2008 with long-term follow-up (median 34 mo) was evaluated for PD-L1 expression in tumor cells and TII cells via immunohistochemistry.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Association between clinicopathological features and PD-L1 expression was estimated using χ² and Fisher's exact tests. For survival analyses, Kaplan-Meier curves with log-rank tests and multivariate Cox proportional hazards regression models were used.

RESULTS AND LIMITATIONS

We found that 32.1% of the tumors and 64.2% of the TII cells expressed PD-L1. Our data demonstrate that penile SqCC patients with PD-L1-positive tumor cells or TII cells are at significant risk of lower cancer-specific survival and that the prognostic value of PD-L1 expression was strongest for tumor cell positivity. The use of tissue microarrays rather than whole sections may be viewed as a limitation.

CONCLUSIONS

Tumor PD-L1 expression independently identifies penile SqCC patients at risk of poor clinical outcomes.

PATIENT SUMMARY

We investigated how many patients with penile cancer had tumors that manufactured PD-L1, a protein that decreases the ability of the immune system to fight cancer. We found that up to one-third of penile tumors make this protein. Patients whose tumors make PD-L1 have more aggressive penile cancer and worse clinical outcomes.

Comparative analysis of immune checkpoint inhibitors and chemotherapy in the treatment of advanced non-small cell lung cancer: A meta-analysis of randomized controlled trials

BACKGROUND

Recently, immune checkpoint inhibitors have shown survival advantage over chemotherapy in the treatment of advanced non-small cell lung cancer (NSCLC). This meta-analysis was conducted to gather and analyze the available evidence (Evidence level I; Randomized Controlled Trials) comparing efficacy and safety of anti-programmed cell death-1 (PD1)/programmed cell death ligand 1 (PD-L1) therapies and chemotherapy in the treatment of advanced NSCLC.

METHODS

A search strategy was devised to identify the randomized controlled trials (RCTs) using electronic databases of PubMed, Cochrane Library, and Web of Science. Hazard ratios or odds ratios obtained for overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and treatment related adverse events (TRAEs) were analyzed using fixed effect model or random effects model. Additionally, subgroup analysis was also performed.

RESULTS

A total of seven RCTs (n = 3867) were identified and selected for inclusion in this meta-analysis. Anti-PD1/PD-L1 therapies (nivolumab, pembrolizumab, atezolizumab) resulted in better OS (HR 0.72 [95% confidence interval [CI] 0.63, 0.82; P < .00001]), PFS (HR 0.84 [95% CI 0.72, 0.97; P < .02]), and ORR (odds ratio [OR] 1.52 [95% CI 1.08, 2.14; P < .02]) in comparison to chemotherapy in advanced NSCLC. Improved safety was observed with anti-PD1/PD-L1 therapies (OR 0.31 [95%CI 0.26, 0.38; P < .00001]). Subgroups analysis revealed Eastern Cooperative Oncology Group Performance Status (ECOG PS) 1 (HR 0.76 [95%CI 0.62, 0.93; P = .007]), squamous cell type (HR 0.76 [95% CI 0.63, 0.92; P = .005]), current/former smoker (HR 0.76 [95% CI 0.63, 0.92; P = .005]), epidermal growth factor receptor (EGFR) wild type (HR 0.67 [95% CI 0.60, 0.76; P < .00001]), Kirsten rat sarcoma oncogene mutation (KRAS) mutant (HR 0.60 [95% CI 0.39, 0.93; P < .02]), and absence of central nervous system (CNS) metastases (HR 0.71 [95% CI 0.63, 0.80; P < .00001]) were associated with better overall survival.

CONCLUSIONS

Anti-PD1/PD-L1 therapies are safe and effective treatment option in advanced non-small cell lung cancer and can be recommended selectively.

Clinicopathological and prognostic significance of PD-L1 expression in sarcoma: A systematic review and meta-analysis

Programmed cell death-ligands 1 (PD-L1) is a key immune checkpoint protein and a promising therapeutic target for malignancy tumor immunotherapy. The prognostic value of PD-L1 in patients with bone and soft tissue sarcoma remains controversial. Therefore, this meta-analysis is conducted to evaluate the associations of PD-L1 expression with overall survival (OS), progression-free survival (PFS), and clinicopathological characteristics of sarcomaA comprehensive literature search of PubMed, Web of Science, Embase, and Cochrane Library was conducted for relevant studies. A total of 14 studies published from 2013 to 2017 were included. The pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were extracted from included studies to assess the association between PD-L1 expression and OS, PFS of patients with sarcoma. Other relevant data were extracted to evaluate the correlations of PD-L1 expression with risk and clinicopathological characteristics of sarcoma. Stata 12.0 software was applied to calculate the strength of association between PD-L1 expression and sarcoma.In total, 14 articles containing 15 independent studies and 1,451 patients were included in this meta-analysis. We found that the high PD-L1 expression was associated with poorer overall survival (HR 1.27, 95% CI: 0.70-1.84 P = .000) and poorer events-free survival (HR 2.05, 95% CI: 1.55-2.70, P = .000) in bone and soft-tissue sarcoma patients. Additionally, we conducted subgroup analysis according to histology type, ethnicity, target of PD-L1 assessment, cutoff, the significant correlations with poor overall survival and events-free survival were also observed. In contrast none of the clinicopathological characteristics (gender, age, tumor site, tumor grade, tumor depth, tumor necrosis rate, metastasis, recurrence, chemotherapy, radiotherapy) was found to be associated with PD-L1 expression in our analysis.The findings from this meta-analysis indicate that PD-L1 expression might be a useful predicative factor of poor prognosis for patients with bone and soft tissue sarcoma.

Prognostic significance of immune cells in non-small cell lung cancer: meta-analysis

Background

Tumor-associated immune cells are prognostic in non-small cell lung cancer (NSCLC) but findings have been conflicting.

Objectives

To determine the prognostic role of immune cells according to localization in NSCLC patients.

Methods

A systematic literature review and meta-analysis was performed on dendritic cell (DC), tumor associated macrophages (TAM), mast cells (MC), natural killer (NK) cells, T and B cells and tumor CTLA-4 and PD-L1 studies.

Results

We analysed 96 articles (n= 21,752 patients). Improved outcomes were seen with increased tumor DCs (overall survival (OS) hazard ratio (HR) 0.55; 95% confidence interval (CI) 0.44-0.68), NK cells (OS HR 0.45; 0.31-0.65), TAMs (OS HR 0.33; 0.17-0.62), M1 TAMs (OS HR 0.10; 0.05-0.21), CD3+ T cells (disease specific survival (DSS) HR 0.64; 0.48-0.86), CD8+ T cells (OS HR 0.78; 0.66-0.93), B cells (OS HR 0.65; 0.42-0.99) and with increased stroma DC (DSS HR 0.62; 0.47-0.83), NK cells (DSS HR 0.51; 0.32-0.82), M1 TAMs (OS HR 0.63; 0.42-0.94), CD4+ T cells (OS HR 0.45; 0.21-0.94), CD8+ T cells (OS HR 0.77; 0.69-0.86) and B cells (OS HR 0.74;0.56-0.99). Poor outcomes were seen with stromal M2 TAMs (OS HR 1.44; 1.06-1.96) and Tregs (relapse free survival (RFS) HR 1.80; 1.34-2.43). Tumor PD-L1 was associated with worse OS (1.40; 1.20-1.69), RFS (1.67) and DFS (1.24).

Conclusion

Tumor and stroma DC, NK cells, M1 TAMs, CD8+ T cells and B cells were associated with improved prognosis and tumor PD-L1, stromal M2 TAMs and Treg cells had poorer prognosis. Higher quality studies are required for confirmation.

Sex disparity in cancer: roles of microRNAs and related functional players

A sexual dimorphism at the cellular level has been suggested to play a role in cancer onset and progression. In particular, very recent studies have unraveled striking differences between cells carrying XX or XY chromosomes in terms of response to stressful stimuli, indicating the presence of genetic and epigenetic differences determining sex-specific metabolic or phenotypic traits. Although this field of investigation is still in its infancy, available data suggest a key role of sexual chromosomes in determining cell life or death. In particular, cells carrying XX chromosomes exhibit a higher adaptive potential and survival behavior in response to microenvironmental variations with respect to XY cells. Cells from females also appear to be equipped with more efficient epigenetic machinery than the male counterpart. In particular, the X chromosome contains an unexpected high number of microRNAs (miRs), at present 118, in comparison with only two miRs localized on chromosome Y, and an average of 40-50 on the autosomes. The regulatory power of these small non-coding RNAs is well recognized, as 30-50% of all protein-coding genes are targeted by miRs and their role in cell fate has been well demonstrated. In addition, several further insights, including DNA methylation patterns that are different in males and females, claim for a significant gender disparity in cancer and in the immune system activity against tumors. In this brief paper, we analyze the state of the art of our knowledge on the implication of miRs encoded on sex chromosomes, and their related functional paths, in the regulation of cell homeostasis and depict possible perspectives for the epigenetic research in the field.

Microsatellite instability is a biomarker for immune checkpoint inhibitors in endometrial cancer

In recent years, it has become evident that tumor cells have immune escape mechanisms, and immune checkpoint inhibitor therapy (anti-PD-1/PD-L1 antibody) has shown benefit in various cancers. In endometrial tumors with microsatellite-instability (MSI), somatic mutations have the potential to encode ''non-self'' immunogenic antigens, and lymphocytes have been shown to infiltrate the tumor. Therefore, immune checkpoint inhibitor therapy might be effective in endometrial cancers with MSI. Expression of mismatch repair (MMR) proteins (MLH1, PMS2, MSH2, and MSH6), the presence of tumor-infiltrating lymphocytes (CD8+), and PD-1/PD-L1 expression were assessed by immunohistochemistry in 149 patients with endometrial cancer. We examined whether tumors with MSI had an enhanced immune microenvironment and whether MSI could be a predictor of the therapeutic effect of PD-1/PD-L1 immunotherapy in endometrial cancer. Loss of MMR protein expression was identified in 42 (28.2%) of 149 patients (MSI group) with endometrial cancer. There was no significant relationship between MSI status and age (p = 0.193), histological grade (p = 0.097), FIGO stage (p = 0.508), pelvic lymph node metastasis (p = 0.139), or depth of myometrial invasion (p = 0.494). However, the presence of tumor-infiltrating lymphocytes (CD8+) and PD-L1/PD-1 expression were significantly higher in the MSI group compared to the microsatellite-stable group (p = 0.002, p = 0.001, and p = 0.008, respectively). These results suggest that immune checkpoint inhibitors (anti-PD-1/PD-L1 antibody) could be effective in endometrial cancers with MSI. The presence of MSI may be a biomarker for good response to PD-1/PD-L1 immunotherapy in endometrial cancer.

PD-L1 expression in lung cancer and its correlation with driver mutations: a meta-analysis

Although many studies have addressed the prognostic value of programmed cell death-ligand 1 (PD-L1) expression in lung cancer, the results remain controversial. A systematic search of the PubMed, EMBASE, and Cochrane Library databases was performed to identify the correlation between PD-L1 expression and driver mutations and overall survival (OS). This meta-analysis enrolled a total of 11,444 patients for 47 studies, and the pooled results showed that increased PD-L1 expression was associated with poor prognosis (HR = 1.40, 95% CI: 1.19-1.65, P < 0.001). In subgroup analysis stratified according to histology types, the pooled results demonstrated that increased PD-L1 expression was an unfavorable prognostic factor for non-small cell lung cancer (NSCLC) (HR = 1.26, 95% CI: 1.05-1.52, P = 0.01) and pulmonary lymphoepithelioma-like carcinoma (LELC) (HR = 3.04, 95% CI: 1.19-7.77, P = 0.02), rather than small cell lung cancer (SCLC) (HR = 0.62, 95% CI: 0.27-1.39, P = 0.24). The pooled ORs indicated that PD-L1 expression was associated with gender, smoking status, histology, differentiation, tumour size, lymph nodal metastasis, TNM stage and EGFR mutation. However, PD-L1 expression was not correlated with ALK rearrangement and KRAS mutations.

Prognostic value of programmed death-ligand 1 in sarcoma: a meta-analysis

Background

The prognostic role of programmed death-ligand 1 (PD-L1) in sarcoma remains controversial. We performed a meta-analysis so as to investigate the impact of PD-L1 on clinicopathlogical findings and survival outcomes in sarcoma.

Materials and Methods

A comprehensive search in PubMed, Embase and the Cochrane Library was conducted for relevant studies. The odds ratios or hazard ratios, at 95% confidence intervals were used as measures for investigation of the correlation between PD-L1 expression and clinicopathlogical features or survival outcomes.

Results

Fourteen eligible studies comprising 868 patients were selected for analysis. Pooled hazard ratios indicated that the association of PD-L1 expression with overall survival in bone sarcoma (osteosarcoma and chondrosarcoma) patients was statistically significant (1.987, 95% CI: 1.224–3.224, p = 0.005), as was its association with event-free survival in bone and soft-tissue sarcoma patients (3.868, 95% CI: 2.298–6.511, p = 0.000). Additionally, the expression of PD-L1 was positively correlated with the infiltration of programmed death 1 (PD-1) positive T-lymphocytes (OR: 4.012, 95% CI: 2.391–6.733, p = 0.000).

Conclusions

Our meta-analysis indicated that high PD-L1 expression is likely to be a negative factor for patients with sarcomas and that it predicts worse survival outcomes.