The predictive and prognostic value of Foxp3+/CD25+ regulatory T cells and PD-L1 expression in triple negative breast cancer

Recent significant developments in cancer immunotherapy have led to important breakthroughs and paradigm shifts in the treatment of malignancy. Although breast cancer traditionally has been considered less immunogenic, triple-negative breast cancer (TNBC) is the most immunogenic subtype with more stromal tumor-infiltrating lymphocytes (TILs) and higher programmed death-ligand 1 (PD-L1) expression. The goal of this study is to evaluate regulatory T cells (Tregs) and PD-L1 expression in TNBC, as well as their associations with clinicopathologic features and the outcomes. Tissue microarrays (TMA) of biopsy and resection specimens of 43 TNBC patients who underwent breast biopsy, neoadjuvant chemotherapy, and mastectomy were prepared. The number of Foxp3+ Tregs, Foxp3+/CD25+ Tregs, and expression of PD-L1 in tumor cells (PD-L1 TCs) and TILs (PD-L1 TILs) were assessed by immunohistochemistry. PD-L1 expression combined positive score (PD-L1 CPS) was calculated according to the manufacturer's guidelines. PD-L1 expression was detected in 72% of the cases, and it expressed in a higher percentage and higher intensity in TILs than TCs in TNBC (p = 0.006 and 0.0005, respectively). PD-L1 TCs, PD-L1 TILs, and PD-L1 CPS were all positively associated with pathologic complete response (pCR) (p = 0.04, 0.03, and 0.02, respectively). PD-L1 TILs and PD-L1 CPS also correlated with TILs and tumor infiltrating lymphocyte volume (TILV). Foxp3+ Tregs and Foxp3+/CD25+ Tregs had strong positive correlation (r = 0.89), and they were positively associated with TILs, TILV, and PD-L1 expression. Foxp3+/CD25+ Tregs, PD-L1 TCs, and PD-L1 CPS were positively correlated with better overall survival (p = 0.04, 0.04 and 0.01, respectively).     

Aligning digital CD8+ scoring and targeted next‐generation sequencing with programmed death ligand 1 expression: a pragmatic approach in early‐stage squamous cell lung carcinoma

Aims

To study programmed death ligand 1 (PD‐L1) expression, tumour‐infiltrating T lymphocytes (TILs) and the molecular context in patients with early‐stage squamous cell lung carcinomas (SCCs).

Methods and results

The study included samples from 40 patients (discovery cohort) and 29 patients (validation cohort) diagnosed with early‐stage SCC. PD‐L1 immunohistochemistry (IHC) was performed with three commercially available clones (E1L3N, SP263 and SP142). CD8⁺ TILs were scored with a digital algorithm. All tumours were analysed with targeted next‐generation sequencing (NGS). Additionally, TP53 mutations were investigated with direct sequencing. In both cohorts, we observed a significant association between CD8⁺ TILs density and high PD‐L1 IHC expression in tumour cells (TCs). Furthermore, high SP142 PD‐L1 expression in immune cells (ICs) was also associated significantly with CD8⁺ TILs density. Therefore, CD8⁺ TILs density discriminated between patients with high versus low PD‐L1 IHC expression with excellent sensitivity and specificity. Interestingly, the highest percentages of PD‐L1‐positive TCs with the three antibodies were found in samples with cyclin‐dependent kinase 6 (CDK6) amplification, with high amplification of proto‐oncogene C‐Myc (CMYC) or with cyclin D1–PI3 kinase subunit alpha (CCND1–PIK3CA) co‐amplification. High SP142 PD‐L1 IHC expression in ICs showed a non‐significant correlation with TP53 mutations. Conversely, most cases with fibroblast growth factor receptor 1 (FGFR1) amplification were negative for all PD‐L1 clones.

Conclusions

Our preliminary results support the use of digital CD8⁺ TILs scoring and targeted NGS alongside PD‐L1 expression. The approach presented herein could help define patients with SCCs candidates to immune checkpoints inhibitors.     

PD-L1 expression in carcinoma of the esophagogastric junction is positively correlated with T-cell infiltration and overall survival

IntroductionIn recent years antitumor immunity and inhibition of checkpoint molecules, such as PD-1 and PD-L1, have emerged as potential therapeutic strategies in advanced stages of various malignancies. We investigated PD-L1 expression in adenocarcinomas of the esophagogastric junction and correlated the results with densitiy of intratumoral T-lymphocytes.MethodsImmunohistochemical staining for PD-L1 was carried out on 135 samples using a tissue microarray. Scoring was done according to the combined positivity score.Results48.1% of tumors (65 cases) showed PD-L1 positivity with a score ≥ 1 while 51.9% were PD-L1 negative (70 cases). A positive correlation between PD-L1 negativity and mucinous and poorly cohesive carcinoma could be shown (p = 0.043), while no association existed for either gender, T-stage, N-stage, grading, surgical resection status, neoadjuvant therapy, distant metastases, lymphovascular or perineural invasion. No correlation of PD-L1 expression and overall survival could be detected (p = 0.497). Again, when stratified according to presence or absence of neoadjuvant therapy, no survival differences could be shown for either group (p = 0.540 and p = 0.736). When PD-L1 expression was correlated with density of tumor-infiltrating T-lymphocytes a positive correlation between PD-L1 positivity and denser T-cell infiltration could be shown (p = 0.001). Concerning overall survival, in PD-L1 negative cases, denser CD8-positive T-cell infiltrates were associated with prolonged survival times (p = 0.045). No differences could be shown for PD-L1 positive cases or CD103-positive T-cells.ConclusionPD-L1 expression is frequent in esophagogastric adenocarcinoma and - when combined with dense CD8 infiltration – PD-L1 negativity correlates with prolonged overall survival.     

Prognostic impact of neutrophils-to-lymphocytes ratio (NLR), PD-L1 expression,and tumor immune microenvironment in laryngeal cancer

PurposeIn laryngeal carcinoma (LSCC), tumor immune microenvironment is attracting increasing interest, given the recent progresses in immunotherapy. Immune cells migrate to tumors as a result of a tumor antigen-induced immune reaction and cancer cells recruit immune regulatory cells to induce an immunosuppressive network, resulting in the escape from host immunity. This interaction reflects both on tumor microenvironment and systemic inflammatory status. Blood neutrophil-to-lymphocyte ratio (NLR), reflecting a highly pro-inflammatory status, has been related to worse oncological survival outcomes.The aim of this study was to analyze in LSCC the relationship between circulating inflammatory cells (also in terms of NLR) and tumor immune microenvironment histopathological features (programmed cell death ligand 1 [PD-L1] expression, and tumor-infiltrating lymphocytes [TILs]), also investigating their clinical-pathological and prognostic significance.MethodsBlood pre-operative NLR, and, at pathology, PD-L1 (in terms of combined positive score [CPS]) and TILs were assessed on 60 consecutive cases of LSCC.ResultsBlood NLR, neutrophils, and lymphocytes counts showed a significant value in predicting DFS and recurrence risk. Moreover, PD-L1 CPS ≥ 1 and TILs count rate ≥30% were associated with higher disease-free survival (DFS) and reduced recurrence risk. A logistic regression model found a significant positive association between increasing NLR values, and PD-L1 CPS < 1 and TILs count rate <30%.ConclusionsFurther studies are needed to better characterize the role of pre-operative blood NLR in association with PD-L1 expression and tumor immune microenvironment features as prognostic factors and markers of anti-tumor immune response in LSCCs, also with regard to the effectiveness of immunotherapeutic protocols.     

Clinicopathologic correlation of programmed death ligand-1 expression in non-small cell lung carcinomas: A report from India

IntroductionIncreased expression of Programmed death ligand-1 (PD-L1) on cancer cells and immune cells predict response to PD-1/PDL1 inhibitors. Data regarding frequency and pattern of PD-L1 expression in NSCLC from India is not available.ObjectivesTo analyse PD-L1 expression on tumour cells (TC) and immune cells (IC) and to correlate PD-L1 expression with baseline clinico-pathological characteristics, oncogenic drivers and outcome data.Materials and methodsPD-L1 expression on tumour cells and immune cells was analysed.ResultsEighty-nine cases of resected NSCLC were included. Squamous cell carcinoma was more common than adenocarcinoma. IC were present in almost all cases. Immunopositivity for PD-L1 in TC and IC was 27% and 18% respectively. PD-L1 immunopositivity in TC or IC did not correlate with age, sex, stage or mutation status however sarcomatoid carcinoma and solid predominant adenocarcinomas showed higher positivity rates. PD-L1 immunopositivity in ICs was found to correlate with better disease free survival.ConclusionPD-L1 immunopositivity was seen in a quarter of NSCLC patients in India. PDL1 positivity on immune cells may be associated with better prognosis in resected NSCLC. However the prognostic value of PD-L1 and clinical response to check point inhibitors in Indian population need to be validated in larger studies.     

The expression of programmed death-ligand 1 and programmed death-ligand 2 in endometrial carcinosarcoma: Correlation with mismatch repair protein expression status,tumor-infiltrating lymphocyte infiltration,and clinical outcomes

BackgroundEndometrial carcinosarcomas have high malignant potential with a high recurrence rate and poor prognosis. Immunotherapy may be a promising treatment option. The aim of this study is to evaluate the expression of PD-L1/PD-L2 and its relationship to mismatch repair (MMR) protein status and tumor-infiltrating lymphocyte (TIL) density.MethodsWe performed immunohistochemical analyses of PD-L1 (clone 22C3), PD-L2 (clone TY25), MSH-2, MSH-6, PMS-2, and MLH-1 in 77 tumors. We count TILs using CD8 antibody. Clinicopathologic features were recorded and statistically correlated with immunohistochemical results. Kaplan-Meier analyses were used to analyze the prognosis.ResultsWhile PD-L1 positivity was seen more commonly in MMR protein deficient tumors (p = 0.010), PD-L2 positivity was seen more commonly in MMR protein proficient tumors (p = 0.003). PD-L1 positivity was also found to be more common in carcinosarcoma with high TIL infiltration. PD-L2 positivity was associated with decreased overall survival (OS) rates (p = 0.043, p = 0.043, respectively), whereas the PD-L1 positivity and TIL density were not significantly associated with OS rate. The OS rate of patients with MMR protein proficient tumors was significantly lower compared with those with MMR protein deficient tumors (p = 0.042). The lower TILs infiltration was associated with a shorter disease-free survival (DFS) rate. PD-L1 and PD-L2 positivity did not affect the DFS rate.ConclusionsPD-L1/PD-L2 might be a better target for immunotherapy in endometrial carcinosarcoma. PD-L2 positivity was also associated with a worse clinical outcome in patients with endometrial carcinosarcoma, suggesting that PD-L2 status can be used to predict clinical behavior. Further studies are needed to elucidate the relationship between PD-L1/PD-L2 expression and therapeutic response.     

Clinicopathological significance of PD-L1 expression in colorectal cancer: Impact of PD-L1 expression on pFOXO1 expression

ObjectiveThis study aimed to evaluate the clinicopathological significance of PD-L1 expression and its impact on phospho-Forkhead box O 1 (pFOXO1) expression in colorectal cancer (CRC).MethodsImmunohistochemical analysis for PD-L1 and pFOXO1 was performed on 265 human CRC tissues. PD-L1 expression was evaluated in the tumor and immune cells. The impact of PD-L1 expression on survival was investigated in relation to the pattern of pFOXO1 expression.ResultsPD-L1 was expressed in 25 (9.4%) and 41 (17.7%) patients in the tumor and immune cells of the 265 CRC tissues, respectively. PD-L1 expression in immune cells (I-PD-L1) was significantly correlated with less lymphatic invasion, lymph node metastasis, and distant metastasis and lower pT and pTNM stages. Additionally, there was a significant correlation between PD-L1 expression in tumor cells (T-PD-L1) and tumor location (right colon), but not the other clinicopathological characteristics. pFOXO1 expression was significantly lower in CRC with high I-PD-L1 expression than in CRC with low or negative I-PD-L1 expression. However, there was no significant correlation between pFOXO1 and T-PD-L1 expression in CRC. Patients with positive pFOXO1 and low or negative I-PD-L1 expression exhibited the worst survival among patients with CRC.ConclusionCollectively, our results indicate that I-PD-L1 expression was significantly correlated with favorable tumor behaviors and better survival. In addition, patients with high I-PD-L1 and low pFOXO1 expressions had a favorable prognosis than those with other I-PD-L1 and pFOXO1 expression patterns.     

Increased PD-L1 expression in high-grade bladder cancer with squamous cell differentiation in Bulgarian and French patients' samples

Urothelial carcinomas (UC) of the bladder are biologically and clinically heterogeneous and the most common malignancy of the urinary tract in developed countries worldwide, where several checkpoint targets as programmed death ligand-1 (PD-L1) and programmed cell death protein (PD-1) have received the most attention in the treatment of bladder cancer. However, the clinicopathological impact of this biomarker has not yet been established enough.ObjectiveTo evaluate programmed death ligand-1 (PD-L1) expression in UCs of the bladder in Bulgarian and French patients' samples.Materials and methodsUrothelial bladder carcinomas cases from 2016–2020 were retrospectively were analyzed. The cohort included 105 cases: 42 (40%) low grade and 63 (60%) high grade. Immunohistochemical (IHC) staining for PD-L1 expression was performed using an anti-PD-L1 primary antibody clone 22C3pharmDx only to 73/105 cases.ResultsApproximately 21/73 cases (28.8%) of urothelial bladder carcinomas demonstrated positive PD-L1 expression, and in 52/73 cases (71.2%) were negative. Positive PD-L1 expression was associated with high grade and high pathologic stage (p < 0.001). We found that PD-L1 was expressed in a significant percentage in UC with squamous differentiation (40%), followed by classic UC (30%). An association between histological grading systems of bladder UC (WHO1973 and WHO 2016) and the TNM-staging system, estimated by Pearson correlation coefficients (r = 0.590 and r = 0.583, respectively, p < 0.001) was observed.ConclusionsWe found that PD-L1 expression is increased in patients with muscle-invasive UC, and PD-L1 might be a new biomarker that correlates with the pathological stage of urothelial bladder cancer and might predict recurrence-free survival.     

Expression of programmed cell death 1/programmed cell death ligand 1 in the tumor microenvironments of primary gastrointestinal diffuse large B cell lymphomas

Background

Gastrointestinal diffuse large B cell lymphoma (GI DLBCL) is the most common gastrointestinal lymphoma. However, there has not been a comprehensive investigation into the expression patterns of programmed cell death 1 (PD-1) and programmed cell death ligand 1(PD-L1) in GI DLBCL tissues.

The relationships between PD-L1 expression,CD8+ TILs and clinico-histomorphological parameters in malignant melanomas

IntroductionMalignant melanomas (MM) are often connected with the expression of PD-L1 protein and the presence of tumor-infiltrating lymphocytes (TILs), however, their impact on prognosis remains controversial. Due to their supposed clinical significance and lack of convincing data, we decided to establish the relationships between CD8 + TIL count, PD-L1 level and certain clinical and histopathological parameters in patients with malignant melanoma, especially those associated with unfavorable prognosis.Materials and methodsWe performed immunohistochemistry for PD-L1 and CD8 on 56 formalin-fixed paraffin-embedded specimens from patients with cutaneous and metastatic malignant melanomas. PD-L1 expression levels were determined by immunohistochemistry (clone 28-8) and subsequently the tumor proportion scores (TPS) were evaluated. CD8 + TIL expressions were classified as either grade 0, 1+, 2+ or 3+, based on the density and distribution of the infiltrating lymphocytes.ResultsThe PD-L1 expression was detected in 20 out of 56 cases (35,71 %). The expression of PD-L1 on tumor cells was significantly increased with higher TILs infiltration in the tumor microenvironment (p = 0,038). Lower TIL score corresponds with poor prognostic clinicopathological parameters such as higher number of mitotic figures (p = 0,005), Clark's level (p = 0,007) and Breslow's depth (p = 0,010).ConclusionsOur results suggest a favorable prognostic value for CD8 + TIL infiltration. Moreover, TIL density was strongly correlated and geographically associated to PD-L1 expression. This analysis provides more insight into the role of TIL count and PD-L1 level in MM and their relationship with each other and association with other prognostic indicators.     

Expression level of PD-L1 is involved in ALDH1A1-mediated poor prognosis in patients with head and neck squamous cell carcinoma

ObjectiveTo evaluate the expression levels of ALDH1A1, PDL1, and PDL2 in head and neck squamous cell carcinoma (HNSCC) patients, and explore their clinical relevance in prognosis of patients with HNSCC.MethodsImmunohistochemistry of ALDH1A1 and PD-L1/PD-L2 in 85 primary HNSCC patients was carried out. The expression level of PD-L2 was assessed with the modified Moratin’s immune response scoring (IRS) system. tumor proportion score (TPS) was defined as the percentage of viable tumor cells showing partial or complete membrane staining at any intensity. The chi-square test and Fisher’s exact test were used to analyze the associations between ALDH1A1 expression and clinicopathological features. The Spearman’s correlation was applied to analyze the correlation of ALDH1A1 expression with PD-L1/PD-L2 expression.Resultskaplan-Meier analysis showed that the expression levels of ALDH1A1 and PD-L1/PD-L2 were inversely associated with recurrence-free survival (RFS; P = 0.001, 0.014, and 0.023, respectively). Moreover, expression levels of ALDH1A1 and PD-L1 were correlated with poor overall survival (OS; P = 0.002 and 0.039, respectively). Furthermore, multivariate logistics regression analyses demonstrated that expression level of ALDH1A1 was independently associated with shorter RFS (P = 0.013) and poorer OS (P = 0.014) in HNSCC patients, and the expression level of PD-L2 was only negatively associated with RFS (P = 0.041), rather than PD-L1. Spearman’s correlation analysis unveiled that expression levels of PD-L1 and PD-L2 were positively correlated with ALDH1A1 expression in HNSCC patients (P = 0.000 and 0.015, respectively). Especially, the patients with expression levels of ALDH1A1 and PD-L1 had the worst prognosis.ConclusionsOur results indicated that ALDH1A1 is an independent prognostic factor in patients with HNSCC, and the expression level of PDL-1 may be involved in ALDH1A1-mediated poor prognosis in patients with HNSCC.     

Clinicopathological significance of the immunologic signature (PDL1, FOXP3+ Tregs,TILs) in early stage triple-negative breast cancer treated with neoadjuvant chemotherapy

Patients with breast cancer are appropriate candidates for neoadjuvant chemotherapy (NAC) to facilitate conservative surgery. The chemotherapeutic agents may exert their action by inducing the anti-tumor immune response. This study aimed to evaluate the tumor immune microenvironment including PD-L1, Foxp3+ Tregs, and TILs count in early stages TNBC patients (stage T1, T2) before and after neoadjuvant chemotherapy and their correlation with the clinical and pathological response. Fifty patients of TNBC patients were enrolled in this study; all of them received neoadjuvant chemotherapy. TILs count, Foxp3+ Tregs, and PD-L1 immunohistochemical expression were investigated in all cases before NAC and then evaluated in residual masses after surgery. Data on the clinical and pathological response to NAC were collected and then statistically analyzed. PDL1 expression was detected in 24% of all studied cases, all of them were node-positive (P < 0.002); while Foxp3+ Tregs expressed in 50% and high TILs in 28%. Pathological complete response (pCR) was achieved in 40% of patients and was associated with high TILs expression (P < 0.02) and absence of Foxp3+ Tregs and PDL1 (P < 0.001 for each). In conclusion, Pathologic complete response to NAC was associated with the immunological profile of TNBC. High TILs expression with concomitant decreased PD-L1 expression and low FOXP3+ Tregs is associated with favorable tumor prognosis. Combined therapeutic approaches aiming to PD-L1 block and Tregs depletion might improve treatment efficacy in TNBC.     

Expression of PD-L1 using SP142 CDx in triple negative breast cancer

Triple negative breast cancer (TNBC) represents a small subtype of breast cancer yet it has the worst outcome. Immunotherapy using immune checkpoint inhibitors combined with chemotherapy was recently approved by the FDA raising the hope for an improved outcome. The approval was based on demonstration of a positive PD-L1 expression using the SP142 CDx assay ¹.We aimed to study a cohort of TNBC patients in terms of prevalence of the PD-L1 expression using the approved assay and to investigate its association with clinicopathological variables.This is a single center retrospective study consisting of 49 TNBC patients who had available archived paraffin-embedded tissue blocks from the primary tumors. All blocks were stained using the SP142 CDx assay as per the manufacture's instruction. Clinicopathological data were collected from medical records.Eighteen of the 49 (36.7%) patients were found to have a score of 1% or more by the immune cell-scoring algorithm. PDL-1 expression was significantly associated with the degree of tumor infiltrating lymphocytes (TILs). No additional significant relationship was found between PD-L1 expression and any of the other investigated clinicopathological variables. Although a trend of favorable prognostic association with PD-L1 expression was noted. The overall and event free survival were significantly related to pathological response to neoadjuvant therapy.Conclusion: Our PD-L1 rate of 36.7% is close to the results of the previously reported 40.9% in the IMpassion 130 trial. There were no significant association between positive PD-L1 expression and clinicopathological variables however a trend of a favorable outcome was observed.     

Clinicopathological significance of the expression of PD-L1 in non-small cell lung cancer

IntroductionPD1/PD-L1 pathway targeting therapies are nowadays an established treatment option for patients with NSCLC. We assessed whether PD-L1 expression in NSCLC tumor cells was associated with specific clinical features or overall survival using four different clones.Methods and resultsA retrospective study included formalin-fixed paraffin embedded (FFPE) surgical tumors from 482 patients. PD-L1 status was assessed with immunohistochemistry in tumor cells on tissue microarrays using clones 28-8, 22C3, SP263 and SP142. Associations with OS were assessed by Kaplan-Meier and multivariate Cox's regression analysis.Patients' median age: 68 years (39–86); histology: adenocarcinoma (AdCa) 61%, squamous-cell carcinoma (SqCC) 33%, and large cell carcinoma (LCC) 6%; p-stage: IA (46%), IB (30%), IIA (10%), IIB (11,4%), IIIA (1,2%), IIIB – IV (0,4%). PD-L1 positivity (≥1%) in NSCLC for clones 28-8, 22C3, SP263, SP142 was 41.5%, 34.2%, 42.7%, 10.4%, respectively (Pearson Chi-square p < 0.0001). PD-L1 expression was correlated with histology, tumor size and grading. Statistically significant association between PD-L1 expression and OS in NSCLC and Non-AdCa was observed with clone SP142 (log-rank p = 0.045 and p = 0.05, respectively). Statistically significant association between PD-L1 expression and OS in LCC was observed with clones 22C3 (log-rank p = 0.009) and SP263 (log-rank p = 0.050).ConclusionsOverexpression of the PD-L1 clone SP142 was associated with poor overall survival in NSCLC and Non-AdCa. Clones 22C3 and SP263 were associated with poor prognosis in LCC. PD-L1 status might serve as a prognostic marker in NSCLC.     

PD-L1 expression by immunohistochemistry in salivary duct carcinoma

BackgroundImmune checkpoint inhibitors play an increasing role in oncologic care. PD-L1 expression is associated with survival and predicts response to PD-1 or PD-L1 inhibitors in a variety of tumors. Our aim is to evaluate the frequency and prognostic significance of PD-L1 expression in salivary duct carcinoma.DesignWe retrospectively evaluated the expression of PD-L1 by two different antibodies (PD-L1 28–8 and PD-L1 22C3) in salivary duct carcinomas. PD-L1 expression in at least 1% of tumor cells was considered immunoreactive. Kaplan-Meier analysis was performed to determine the impact of PD-L1 expression on survival; differences between survival curves were assessed by the chi-square test, and pairwise comparisons of factors were assessed with the log-rank test.ResultsA total of 113 patients' specimens were evaluated. Seventy-six (76%) of the patients were male. Mean age at time of presentation was 61.2 (SD = 12.4) years. PD-L1 expression was found in 26% of the samples. Median follow-up time was 36.6 months (range = 1.4–249 months). Overall survival at 3, 5 and 10 years were 52.6%, 37.9% and 25.6%, respectively. There was no statistical difference in survival between patients with PD-L1-immunoreactive tumors and those without, regardless of which antibody was used (chi² result for all plots: p = 0.53; log rank test for pairwise comparison: p > 0.256).ConclusionIn our analysis, PD-L1 expression occurred in a small proportion of salivary duct carcinomas, usually at low levels, and did not correlate with survival. Its predictive value and utility in selecting patients with salivary duct carcinoma who might benefit from PD-1/PD-L1 inhibitors warrants further investigation.     

The PD-L1/PD-1 axis expression on tumor-infiltrating immune cells and tumor cells in pediatric rhabdomyosarcoma

BackgroundActivation of immune checkpoints, e.g. PD-1/PD-L1 axis, in cancer microenvironment, enables evasion of host anti-cancer immune response and drives tumor progression. To date, there have been only a few studies analyzing PD-1/PD-L1 expression in pediatric malignancies.AimIn the current study, we aimed to assess PD-L1 and PD-1 expression in pediatric rhabdomyosarcoma (RMS) and to investigate their clinicopathological associations.Materials and methods: The study enrolled 31 children with RMS. Tissue microarrays with representative tumor tissue samples were stained with anti-PD-1 NAT105 clone (Ventana, Roche) and two different antibodies against PD-L1: SP142 (Ventana, Roche) and 22C3 (DAKO). Adequate positive controls were applied. Their expression was assessed in tumor-associated immune cells (TAICs) and in the tumor cells separately.ResultsWe did not detect any positive PD-L1 staining in analyzed tumors using SP142 antibody; however, in 11 cases (35.48%) its expression was revealed by means of 22C3 clone. The staining was restricted to TAICs in all cases, which no reaction in tumor cells. The 5-year relapse free survival (RFS) rate was significantly higher in PD-L1 positive cases (61.5% vs 25.0%, p = 0.024), but it most likely results from more frequent PD-L1 expression in low-stage RMS. PD-1 expression on TAICs was detected in 7 cases and did not influence the prognosis.ConclusionsWe found that PD-L1 expression on TAICs, as detected with the use of 22C3 clone but not SP142 antibody, tends to be associated with low-stage RMS in children. PD-1 expression on TAICs in RMS is neither associated with distinct clinical course nor with clinicopathological features.     

Expression of programmed cell death-ligand 1 in oral squamous cell carcinoma and oral leukoplakia is associated with disease progress and CD8+ tumor-infiltrating lymphocytes

ObjectiveIn recent years, monoclonal antibodies targeting programmed cell death-ligand 1 (PD-L1) have become a promising cancer immunotherapy. However, the role of PD-L1 in oral squamous cell carcinoma (OSCC) and oral potentially malignant disorders (OPMDs), including oral leukoplakia (OLK), remains controversial. The aim of the present study was to investigate the expression level of PD-L1 in OSCC and OPMDs, and examine its relationship with CD8 expression and different clinicopathological features.MethodExpression of PD-L1 and CD8 were conducted in 41 OSCC, 21 OLK, and 25 normal mucosa samples by immunohistochemistry. Then, the density of PD-L1 expression was measured, and its correlation with CD8 expression and different clinicopathological features was analyzed.ResultsPD-L1 protein was detected in 97.6% of OSCC, 61.9% of OLK, and 0% of normal tissues. PD-L1 was highly expressed in human OSCC tissue (P < 0.0001), when compared to both OLK and control tissues. PD-L1 positivity was significantly associated with CD8 density (P < 0.0001, r = 0.8491). The PD-L1 high expression OSCC group displayed a trend for improved overall survival (OS) and disease-free survival (DFS) compared to the low expression group, although the differences were not significant. Moreover, the expression level of PD-L1 in OSCC was positively correlated with the pathological grade (P < 0.0001), but it was independent of age, gender, smoking, drinking, tumor size, lymph node status, or recurrence (P > 0.05). Also, there was a significant upregulation of PD-L1 expression observed in the OLK group compared to the control group (P < 0.0001). PD-L1 positivity in OLK patients was associated with gender and smoking habits (P < 0.05), but it did not correlate with age, drinking, or dysplasia (P > 0.05).ConclusionThe upregulation of PD-L1 may be associated with disease progress and CD8+ tumor-infiltrating lymphocytes in oral premalignant and malignant lesions.     

Programmed cell death ligand 1 (PD-L1) expression on gastric cancer and its relationship with clinicopathologic factors

Background: Targeting the immune checkpoints in solid tumors becomes hot recently. Programmed cell death ligand 1 (PD-L1) is ligand for programmed death 1 (PD-1), which is known to negatively regulate T-cell activation. In the present study, we investigated the expression of PD-L1 in tumor specimens of gastric cancer and its relationships with clinicopathological variables and survival. Methods: The expression of PD-L1 in 132 surgically resected specimens of stage II and III gastric cancer was evaluated by immunohistochemistry in microarray tissue. Results: Expression of PD-L1 was observed in 50.8% (67/132) of gastric cancer tumor specimens. Patients whose tumor size over 5cm had a higher positive rate of PD-L1 expression. There was no relationship between the expression of PD-L1 and other clinicopathological variables including age, gender, clinical stage, location as well as histological differentiation. PD-L1 positive patients had significantly poorer survival than negative patients. The 5-year survival rates was 83.1% in those with PD-L1 negative patients and 50.7% for PD-L1 positive patients (P<0.001). The multivariate analysis indicated that both PD-L1 positive and Tumor-node-metastasis stage were independent prognostic factors in gastric cancer patients (P=0.001 and 0.025, respectively). Conclusions: The expression of PD-L1 was found in half of stages II and III gastric cancer patients. Positive of PD-L1 expression indicated poor survival in Chinese stages II and III gastric adenocarcinoma patients. These results may provide the clue for immunotherapy in the adjuvant treatment setting of gastric cancer patients.     

PD-L1 immuno-expression assay in thymomas: Study of 84 cases and review of literature

Background and aimsProgrammed death ligand 1 (PD-L1), an immune check point inhibitor, is known to be expressed in several malignancies and is being considered as a prognostic factor and a potential immunotherapeutic target. The aim of this study was to characterize PD-L1 expression in thymomas and to determine correlation with clinicopathological features and previously published studies in the literature.MethodsTissue microarrays were prepared from selected blocks of thymomas and immunohistochemistry (IHC) for PD-L1 was performed. Cases were considered as PD-L1 positive or negative depending on whether the percentage of stained thymic epithelial cells were <25 or >25%. Results were compared clinically and with previously published studies using Google and Pubmed search engines.ResultsOf 84 cases of thymoma, 69 (82.1%) revealed PD-L1 positivity in >25% cells. 94.23% of type B thymoma subtypes (B1/B2/B3) were PD-L1 positive (P < 0.001). There was no correlation of PD-L1 with age, gender, myasthenia gravis, the tumor size or stage of disease. Nine studies were available in the literature; most of which showed PD-L1 expression in higher stage and B subtype however percentage positivity varied from 53.7% to over 90%.ConclusionsPD-L1 expression is frequent in type B (B1/B2/B3) thymomas. It can be easily evaluated by IHC even on small biopsies in unresectable cases, thereby enabling improved clinical evaluation as well as prognostic stratification of patients. It will serve as a potential indicator for benefit from anti-PD-L1 antibody immunotherapy in thymomas.     

Tumor-infiltrating lymphocytes and PD-L1 in breast cancer (and,what happened to medullary carcinoma?)

Tumor-infiltrating lymphocytes (TILs) and PD-L1 have emerged as important immune biomarkers in breast cancer, particularly triple negative breast carcinomas (TNBC) and human epidermal growth factor-2 positive (HER-2⁺) breast carcinomas. These components of the tumor immune microenvironment can be harnessed or targeted with immunotherapy, which represents a significant advancement in the management of TNBC. TILs are a prognostic biomarker in breast cancer, and this recognition has led to reclassification of medullary carcinoma (which were TILs rich by definition) as a pattern of invasive ductal carcinoma (no special type) rather than a distinct histologic type. PD-L1 is a predictive biomarker in TNBC, and two different PD-L1 assays have been approved as companion diagnostics for immune checkpoint inhibition in TNBC. This review will cover the roles of TILs and PD-L1 testing in breast cancer, both of which provide important clinical information to guide patient prognosis and therapy. This is a rapidly evolving and exciting field with significant implications for patient care.