Prognostic impact of programmed cell death ligand 1 (PD-L1) expression and its association with epithelial-mesenchymal transition in extrahepatic cholangiocarcinoma.
ABSTRACT: Extrahepatic cholangiocarcinoma (eCCA) has a poor prognosis. Although the possibility of immunotherapy has been studied, immune checkpoint molecules such as programmed death ligand 1 (PD-L1) in eCCA are not well understood. Epithelial-mesenchymal transition (EMT) has recently been shown to regulate PD-L1 expression. Our aims were to assess the clinicopathological significance of tumor-infiltrating lymphocytes (TILs) and tumor PD-L1 expression in eCCA and to compare these immune responses with EMT marker expression. In this retrospective study, we conducted immunohistochemical analyses for 117 patients with eCCA. We stained for CD4, CD8, Foxp3, and PD-L1 as markers reflecting local immune responses, and for E-cadherin, N-cadherin, vimentin, ZEB1, ZEB2, SNAIL, and TWIST as markers associated with EMT. High numbers of CD4+ and CD8+ TILs correlated with node-negative (P = 0.009 and P = 0.046, respectively) and low SNAIL expression (P = 0.016 and P = 0.022, respectively). High PD-L1 expression was associated with poor histopathological classification (P = 0.034), and low E-cadherin (P = 0.001), high N-cadherin (P = 0.044), high vimentin (P < 0.001) and high ZEB1 (P = 0.036) expression. Multivariate analysis showed that CD4+ TILs, PD-L1 expression and N-cadherin expression were independent prognostic factors (hazard ratio (HR) = 0.61; 95% confidence interval (CI) = 0.38-1.00; HR=4.27; 95% CI = 1.82-9.39; HR = 2.20; 95% CI = 1.18-3.92, respectively). These findings could help to identify potential biomarkers for predicting not only the prognosis, but also the therapeutic response to immunotherapy for eCCA.
Project description:Programmed death-ligand 1 (PD-L1) plays a crucial role in the host immune system in cancer progression. The gene promoter region of PD-L1 also contains a binding site for ZEB1, a transcription factor related to epithelial-mesenchymal transition (EMT). The purpose of this study was to clarify the relationship between PD-L1 and EMT and its clinical importance in esophageal squamous cell carcinoma (ESCC). PD-L1 and ZEB1 expression at the tumor invasive front was examined by immunohistochemistry in resected specimens from 90 patients with ESCC who underwent surgery without preoperative therapy, and their expression and clinicopathological factors were compared. ZEB1 and PD-L1 expression was determined in TE8 cells, which demonstrate the EMT phenotype, following ZEB1 knockdown by siZEB1. TE5, TE6 and TE11 cells with non-EMT phenotype were also used for studies of TGF-?1-dependent EMT induction and ZEB1 and PD-L1 expression. In cases of high PD-L1 expression at the invasive front, significantly greater depth of tumor invasion, EMT, and less CD8+ lymphocyte infiltration were observed. High PD-L1 expression was also associated with worse overall and relapse-free survival. A correlation was observed between PD-L1 and ZEB1 expression. In TE8 cells, siZEB1 suppressed PD-L1 and promoted E-cadherin mRNA and protein expression. TGF-?1 induced EMT and surface expression of PD-L1 in TE5, TE6 and TE11 cell lines. PD-L1 expression at the ESCC invasive front was related to ZEB1 expression, EMT and poor prognosis. We suggest that a cooperative mechanism bridging between tumor immune avoidance and EMT contributes to tumor malignancy in ESCC.
Project description:BACKGROUND:The significance of epithelial-mesenchymal transition (EMT) and immune checkpoint proteins in thymic carcinoma remains unknown. We examined the clinical significance of EMT, tumor-infiltrating lymphocytes expressing the immune checkpoint protein, programmed cell death 1 (PD-1 + TILs), and the expression of PD-1 ligand 1 (PD-L1) in thymic carcinoma (TC). We also investigated the relationships between these immune checkpoint proteins and the EMT status and examined the impact of induction chemotherapy on patients with tumors that express these proteins. METHODS:The relationship between PD-1 + TILs/PD-L1 and clinicopathological findings including EMT was investigated by immunohistochemistry (IHC) of surgically resected samples from 43 patients with TC. In 15 patients receiving induction therapy (IT), those factors were compared before and after IT. RESULTS:With IHC, 26 cases (60.5%) were positive for PD-L1, and 19 cases were positive for PD-1 + TILs (44.2%). The disease-free survival rate in patients showing EMT and who were PD-1/PD-L1 positive was significantly worse compared to negative cases (EMT; P = 0.0095, PD-1; P = 0.001, PD-L1; P = 0.0037). We found a significant relationship between PD-L1 and EMT status (P = 0.01). In patients who received IT, PD-L1 increased, and the change was strongly correlated with EMT status (P = 0.01). CONCLUSION:Epithelial-mesenchymal transition, PD-L1, and PD-1 + TILs have prognostic impact, and PD-L1 is correlated with EMT status. PD-L1 expression after IT was significantly higher compared to before IT and was correlated with the EMT change. Thus, PD-L1 may be upregulated during EMT, and anti-PD-1/PD-L1 immunotherapy may provide reliable treatment of TC in combination with chemotherapy.
Project description:BACKGROUND:Blocking the programmed death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) pathway in hepatocellular carcinoma (HCC) is a very promising approach in immunotherapy. However, the correlation and prognostic values of serum soluble PD-1 and PD-L1 (sPD-1/sPD-L1) have not been explored conjointly in HCC patients. METHODS:This study retrospectively included 120 HCC patients receiving radical resection. The serum levels of sPD-1/sPD-L1 and inflammatory cytokines were measured by antibody array assay. Immunohistochemistry was applied to assess both the expression of membrane-bound PD-L1, and the number of CD4+ tumor-infiltrating lymphocytes (TILs) and CD8+ TILs. RESULTS:The best cut-off values of sPD-1 and sPD-L1 for predicting disease-free survival (DFS) were 33.0 µg/ml and 11.2 µg/ml, respectively. Multivariable analysis showed that sPD-L1 was a negative independent prognostic factor [DFS, Hazard Ratio (HR) 2.58, 95% CI 1.14-5.84, P = 0.023; overall survival (OS), HR 1.77, 95% CI 1.01-3.12, P = 0.048], while sPD-1 was a favorable independent prognostic factor (DFS, HR 0.32, 95% CI 0.14-0.74, P = 0.007; OS, HR 0.54, 95% CI 0.30-0.98, P = 0.044) in HCC patients. We also observed some similar associations between inflammatory cytokines (IL-10, IL-17, TNF-α) and sPD-1 or sPD-L1, as well as a close positive association between sPD-1 and sPD-L1. No significant associations of sPD-1/sPD-L1 with either intra-tumoral PD-L1 expression, or the numbers of CD4+ TILs and CD8+ TILs were determined. CONCLUSIONS:Our findings indicate that sPD-1 and sPD-L1 are independent prognostic factors with opposite prognostic roles in predicting both DFS and OS in HCC patients.
Project description:PURPOSE:The purpose of the study was to evaluate protein expression of PD-L1 and CD20 as prognostic biomarkers of patient outcome in inflammatory breast cancer (IBC) samples. METHODS:PD-L1 and CD20 protein expression was measured by immunohistochemistry in 221 pretreatment IBC biopsies. PD-L1 was assessed in tumor cells (PD-L1+ tumor cells) and tumor stromal infiltrating lymphocytes (PD-L1+ TILs); CD20 was scored in tumor-infiltrating B cells. Kaplan-Meier curves and Cox proportional hazard models were used for survival analysis. RESULTS:PD-L1+ tumor cells, PD-L1+ TILs, and CD20+ TILs were found in 8%, 66%, and 62% of IBC, respectively. PD-L1+ tumor cells strongly correlated with high TILs, pathological complete response (pCR), CD20+ TILs, but marginally with breast cancer-specific survival (BCSS, P?=?0.057). PD-L1+ TILs strongly correlated with high TILs, CD20+ TILs, and longer disease-free survival (DFS) in all IBC and in triple-negative (TN) IBC (P?<?0.035). IBC and TN IBC patients with tumors containing both CD20+ TILs and PD-L1+ TILs (CD20+TILs/PD-L1+TILs) showed longer DFS and improved BCSS (P?<?0.002) than patients lacking both, or those with either CD20+ TILs or PD-L1+ TILs alone. In multivariate analyses, CD20+TILs/PD-L1+TILs status was an independent prognostic factor for DFS in IBC (hazard ratio (HR): 0.53, 95% CI 0.37-0.77) and TN IBC (HR: 0.39 95% CI 0.17-0.88), and for BCSS in IBC (HR: 0.60 95% CI 0.43-0.85) and TN IBC (HR: 0.38 95% CI 0.17-0.83). CONCLUSION:CD20+TILs/PD-L1+TILs status represents an independent favorable prognostic factor in IBC and TN IBC, suggesting a critical role for B cells in antitumor immune responses. Anti-PD-1/PD-L1 and B cell-activating immunotherapies should be explored in these settings.
Project description:To better understand the expression pattern of programmed death-ligand 1 (PD-L1) expression in different breast cancer types, we characterized PD-L1 expression in tumor and tumor-infiltrating immune cells, in relation to mutation rate, BRCA1-like status and survival. We analyzed 410 primary treatment-naive breast tumors comprising 162 estrogen receptor-positive (ER+) and HER2-, 101 HER2+ and 147 triple-negative (TN) cancers. Pathologists quantified tumor-infiltrating lymphocytes (TILs) and PD-L1 expression in tumor cells and TILs using whole slides and tissue microarray. Mutation rate was assessed by DNA sequencing, BRCA1-like status using multiplex ligation-dependent probe amplification, and immune landscape by multiplex image analyses of CD4, CD68, CD8, FOXP3, cytokeratin, and PD-L1. Half of PD-L1 scores evaluated by tissue microarray were false negatives compared to whole slide evaluations. We observed at least 1% of PD-L1-positive (PD-L1+) cells in 53.1% of ER+HER2-, 73.3% of HER2+, and 84.4% of TN tumors. PD-L1 expression was higher in ductal compared to lobular carcinomas, also within ER+HER2- tumors (p = 0.04). High PD-L1+ TILs score (> 50%) was independently associated with better outcome in TN tumors (HR = 0.27; 95%CI = 0.10-0.69). Within TN tumors, PD-L1 and TIL scores showed a modest but significant positive association with the number of silent mutations, but no association with BRCA1-like status. Multiplex image analyses indicated that PD-L1 is expressed on multiple immune cells (CD68+ macrophages, CD4+, FOXP3+, and CD8+ T cells) in the breast tumor microenvironment, independent of the PD-L1 status of the tumor cells. We found no evidence that levels of PD-L1+ TILs in TN breast cancer are driven by high mutation rate or BRCA1-like status.
Project description:Although the role of PD-L1 in suppressing the anti-tumor immune response is extensively documented, recent discoveries indicate a distinct tumor-intrinsic role for PD-L1 in modulating epithelial-to-mesenchymal transition (EMT), cancer stem cell (CSC)-like phenotype, metastasis and resistance to therapy. In this review, we will focus on the newly discovered functions of PD-L1 in the regulation of cancer development, describe underlying molecular mechanisms responsible for PD-L1 upregulation and discuss current insights into novel components of PD-L1 signaling. Furthermore, we summarize our current understanding of the link between PD-L1 signaling and the EMT program as well as the CSC state. Tumor cell-intrinsic PD-L1 clearly contributes to cancer stemness, EMT, tumor invasion and chemoresistance in multiple tumor types. Conversely, activation of OCT4 signaling and upregulation of EMT inducer ZEB1 induce PD-L1 expression in cancer cells, thereby suggesting a possible immune evasion mechanism employed by cancer stem cells during metastasis. Our meta-analysis demonstrated that PD-L1 is co-amplified along with MYC, SOX2, N-cadherin and SNAI1 in the TCGA endometrial and ovarian cancer datasets. Further identification of immune-independent PD-L1 functions and characterization of crucial signaling events upstream or downstream of PD-L1 in diverse cancer types and specific cancer subtypes, would provide additional targets and new therapeutic approaches.
Project description:Immunotherapy targeting PD-1/PD-L1 axis showed benefits in cancer. Prognostic significance of tumour infiltrating lymphocytes (TILs) has been determined. We evaluated PD-L1 protein expression in tumour cells and TILs, PD-L1 mRNA level and various histopathologic factors including TILs using 167 formalin-fixed paraffin embedded tissues and 39 fresh tissue of HER2-positive breast cancer. TILs level and PD-L1 expression in tumour cells and TILs were significantly correlated one another. PD-L1 positivity in tumour cells was associated with high histologic grade and high TILs level (p?<?0.001, both). High PD-L1 immunoscore in TILs and high total immunoscore (in tumour cells and TILs) of PD-L1 were correlated with high histologic grade (p?=?0.001 and p?<?0.001, respectively), absence of lymphovascular invasion (p?=?0.012 and p?=?0.007, respectively), negative hormone receptor expression (p?=?0.044 and p?=?0.001, respectively) and high TILs level (p?<?0.001, both). High PD-L1 mRNA expression was associated with high TILs level (p?<?0.001, both). PD-L1 positivity in tumour cells was associated with better disease-free survival in HR-/HER2+ breast cancer (p?=?0.039). PD-L1 expression in tumour cells and TILs are significantly associated with TILs level in HER2-positive breast cancer. PD-L1 expression in tumour cells might be positive prognostic factor in HR-/HER2+ breast cancers.
Project description:BACKGROUND:High Programmed death ligand 1 (PD-L1) expression are thought to be necessary to PD-1/PD-L1 axis blockades in many tumors. The aim of the study was to explore the variation of PD-L1 expression after neoadjuvant chemotherapy (NAC) in cervical squamous cell carcinoma (SCC) and its clinical implications. METHODS:A total of 142 paired SCC specimens before and after platinum-based NAC were obtained from cervical cancer patients. The expression of PD-L1 and CD3+, CD4+, CD8+ tumor infiltrating lymphocytes (TILs) was detected by immunohistochemistry and the association between TILs, chemotherapy response, clinical outcome and PD-L1 expression was evaluated. RESULTS:The fraction of patients with high PD-L1 expression was significantly increased from 32.4 to 46.5% after NAC (?2?=?5.897, p?=?0.015), while the increase of CD3+, CD4+, CD8+ TILs was not significant. High PD-L1 expression was not associated with CD3+, CD4+, CD8+ TILs before NAC, however CD8+ TILs infiltration was positively associated with high PD-L1 expression after NAC (r?=?0.205, p?=?0.014). The decreased PD-L1 expression was more observed in patients with clinical response to NAC (?2?=?6.890, p?=?0.009). A longer DFS was seen in patients with decreased PD-L1 expression than those with elevated or stable PD-L1 expression (p?=?0.048, 95% CI: 0.091-0.987), while the difference was not significant in multivariate analysis (p?=?0.113, 95% CI: 0.108-1.266). CONCLUSIONS:Cisplatin based chemotherapy can increase PD-L1 expression in cervical cancer. The increased PD-L1 expression and a lymphocyte predominant microenvironment after chemotherapy provide a rational for use of PD-1/PD-L1 axis-inhibitor in the neoadjuvant setting.
Project description:While the importance of programmed death-ligand 1 (PD-L1), mutation burden caused by microsatellite instability (MSI), and CD8+ tumor infiltrating lymphocytes (TILs) has become evident, the significance of PD-L1 expression on prognosis still remains controversial. We evaluated the usefulness of combined markers of PD-L1 and MSI or CD8+ TILs as a prognostic biomarker in gastric cancer. A total of 283 patients with gastric cancer were reviewed retrospectively. PD-L1 expression on >5% tumor cells was defined as PD-L1-positive. PD-L1-positive rate was 15.5% (44/283). PD-L1 positivity was significantly correlated with invasive and advanced cancer and also significantly correlated with MSI, whereas no significance was observed with CD8+ TILs. Kaplan-Meier analysis showed that PD-L1 positivity significantly correlated with a poor prognosis (p = 0.0025). Multivariate analysis revealed that PD-L1 positivity was an independent poor prognostic factor (hazard ratio [HR]: 1.97, p = 0.0106) along with diffuse histological type and lymph node metastases. Combinations of PD-L1 and MSI (HR: 2.18) or CD8+ TILs (HR: 2.57) were stronger predictive factors for prognosis than PD-L1 alone. In conclusion, combined markers of PD-L1 and MSI or CD8+ TILs may be more useful prognostic biomarkers in gastric cancer, and better clarify the immune status of gastric cancer patients.