PD-L1 and c-MET expression and survival in patients with small cell lung cancer

Molecular epidemiology study of programmed death ligand 1 and ligand 2 protein expression assessed by immunohistochemistry in extensive-stage small-cell lung cancer

Objectives

Prevalence of tumor PD-L1 expression in extensive-stage small-cell lung cancer (ES-SCLC) is variable, and data on PD-L2 expression are limited. The prognostic values of these biomarkers are not well understood. The current study was conducted to address these data gaps.

Methods

A retrospective cohort study of Danish patients with histologically confirmed ES-SCLC and evaluable tumor samples who were receiving usual care before the introduction of immunotherapy was conducted. Protein expression of PD-L1 and PD-L2 was determined by immunohistochemistry (IHC) using the PD-L1 IHC 22C3 pharmDx assay and a PD-L2 IHC assay using a propriety mouse monoclonal antibody. A combined positive score (CPS) of ≥1 was used to define biomarker positivity. Kaplan-Meier plots and Cox proportional hazard models were employed to assess the relationship between PD-L1 and PD-L2 protein expression and OS.

Results

Among 80 patients, 31% (n=25) and 36% (n=29) had disease positive for PD-L1 and PD-L2, respectively. Overall, 85% (n=68) of patients had concordant PD-L1/PD-L2 status; 26% (n=21) had double positive disease (both PD-L1 and PD-L2 CPS ≥1) and 59% (n=47) had double negative disease (both PD-L1 and PD-L2 CPS <1). PD-L1 and PD-L2 positivity were each associated with longer OS (unadjusted hazard ratios [HRs], 0.35 [95% CI, 0.21-0.61] and 0.50 [95% CI, 0.31-0.82]); the associations persisted after adjustment for several known prognostic factors (HRs, 0.41 [95% CI, 0.22-0.75] and 0.44 [95% CI, 0.25-0.79] for PD-L1 and PD-L2 positivity, respectively). When evaluating OS in patients with double positive disease, unadjusted and adjusted HRs for double positive compared with double negative were similar to those with only PD-L1 or PD-L2 positivity (unadjusted HR, 0.36 [95% CI, 0.20-0.64]; adjusted HR, 0.36 [0.18-0.73]).

Conclusion

PD-L1 and PD-L2 positivity were observed in approximately one-third of assessed ES-SCLC tumor samples and were highly congruent. Patients with PD-L1 and PD-L2 positivity, alone or combined, were associated with longer OS, independent of other prognostic factors.

Plasma hepatocyte growth factor as a noninvasive biomarker in small cell lung cancer

BACKGROUND

Hepatocyte growth factor (HGF) is a peptide-containing multifunctional cytokine, which is overexpressed and/or activated in multiple malignancies and is reported to be associated with tumor development and inferior survival. At present, the role of HGF in small cell lung cancer (SCLC) has not been fully explored yet.

MATERIALS AND METHODS

The expression of HGF and its value in predicting survival in SCLC were explored from GEO database and in pan-cancer analysis. Furthermore, we detected the expression of HGF using tumor tissue and paired plasma samples from a validation cohort of 71 SCLC patients at our institute. Correlation between tumor and plasma HGF expression and the prognostic values were analyzed.

RESULTS

GEO database analysis revealed that tumor tissue had lower HGF expression than paired normal tissue in SCLC. At our institute, immunohistochemical staining showed negative expression of HGF in tumor tissue of SCLC at our institute (47/47, 100%). The average baseline plasma HGF was 1.28 (range,0.42-4.35) ng/ml. However, plasma HGF was higher in SCLC patients with patients with N3, M1, liver metastasis (LM) and bone metastasis (BM) disease compared with those N0 - 2 (1.25 vs. 1.75 ng/mL, P = 0.000), M0 (1.26 vs. 1.63 ng/mL, P = 0.003), non-LM (1.32 vs. 2.06 ng/mL, P = 0.009), and non-BM (1.35 vs. 1.77 ng/mL, P = 0.047), respectively. Multivariate analysis revealed plasma HGF was an independent predictor for LM and prognostic factor of OS.

CONCLUSION

Our results revealed that plasma HGF rather than tumor HGF exhibited a potential role in predicting metastasis and survival in SCLC. Plasma HGF might be used as a non-invasive detecting and monitoring tool for SCLC.

What role does PDL1 play in EMT changes in tumors and fibrosis?

Epithelial-mesenchymal transformation (EMT) plays a pivotal role in embryonic development, tissue fibrosis, repair, and tumor invasiveness. Emerging studies have highlighted the close association between EMT and immune checkpoint molecules, particularly programmed cell death ligand 1 (PDL1). PDL1 exerts its influence on EMT through bidirectional regulation. EMT-associated factors, such as YB1, enhance PDL1 expression by directly binding to its promoter. Conversely, PDL1 signaling triggers downstream pathways like PI3K/AKT and MAPK, promoting EMT and facilitating cancer cell migration and invasion. Targeting PDL1 holds promise as a therapeutic strategy for EMT-related diseases, including cancer and fibrosis. Indeed, PDL1 inhibitors, such as pembrolizumab and nivolumab, have shown promising results in clinical trials for various cancers. Recent research has also indicated their potential benefit in fibrosis treatment in reducing fibroblast activation and extracellular matrix deposition, thereby addressing fibrosis. In this review, we examine the multifaceted role of PDL1 in immunomodulation, growth, and fibrosis promotion. We discuss the challenges, mechanisms, and clinical observations related to PDL1, including the limitations of the PD1/PDL1 axis in treatment and PD1-independent intrinsic PDL1 signaling. Our study highlights the dynamic changes in PDL1 expression during the EMT process across various tumor types. Through interplay between PDL1 and EMT, we uncover co-directional alterations, regulatory pathways, and diverse changes resulting from PDL1 intervention in oncology. Additionally, our findings emphasize the dual role of PDL1 in promoting fibrosis and modulating immune responses across multiple diseases, with potential implications for therapeutic approaches. We particularly investigate the therapeutic potential of targeting PDL1 in type II EMT fibrosis: strike balance between fibrosis modulation and immune response regulation. This analysis provides valuable insights into the multifaceted functions of PDL1 and contributes to our understanding of its complex mechanisms and therapeutic implications.

PDL-1 expression in lung carcinoma and its correlation with clinicopathological and prognostic characteristics

Lung cancers have high incidence and high mortality rates. The immune checkpoints as programmed death ligand 1 (PDL-1) can suppress the tumor immune reaction. So, their blocking seems to be a way to treat tumors. This study assesses PDL-1 immunohistochemical expression in lung cancer, and its correlation with prognosis. It included 62 specimens of lung cancer in Hospitals of Mansoura Faculty of Medicine, Egypt. Seventy-one percent of cases showed positive PDL-1 and about 59.1% of them showed high expression. PDL-1 expression in NSCLC was significantly higher than in SCLC (P = 0.019). There were no significant associations between PDL-1 expression and other clinicopathological parameters. A significant mild positive correlation between PDL-1 and EGFR marker was found (P = 0.006). The mean overall survival in cases with positive PDL-1 was lower than negative cases (P = 0.37). Also, progression-free survival was lower among PDL-1 positive cases compared to negative cases (P = 0.5). This study reports that immune checkpoint, PDL-1 is overexpressed in lung cancer especially NSCLC. It is correlated with EGFR overexpression. PDL-1 could have potential to be an effective immune target for lung cancer immunotherapy. But the presence of PD-L1-negative tumors highlights the importance of searching for alternative or combination treatment strategies.Abbreviations: AC: Adenocarcinoma; COPD: Chronic Obstructive Pulmonary Diseases; CTLA-4: Cytotoxic T-lymphocyte-associated protein 4; EGFR: Epidermal Growth Factor Receptor; IHC: Immunohistochemical; NSCLC: Non-Small Cell Lung Cancer; OS: Overall Survival; PD1: Programmed Death 1; PDL-1: Programmed Death ligand 1; PFS: Progression Free Survival; SCC: Squamous cell carcinoma; SCLC: Small Cell Lung Cancer; SD: Standard Deviation; TCR: T-cell receptor; TPS: Tumor Proportion Score.

Correlation analysis between serum neuron-specific enolase and the detection of gene mutations in lung adenocarcinoma

Background

Lung cancer is a chronic, progressive and malignant disease associated with ever-growing incidence and mortality. Targeted therapy plays an important role in the clinical treatment of lung cancer. Besides, neuron-specific enolase (NSE), an intracellular enzyme, is highly correlated with the targeted treatment outcome in patients with non-small cell lung cancer (NSCLC). The present study aimed to explore the correlation of NSE with the detection of gene mutations.

Methods

It is a case-control study. From June 2017 to October 2019, the newly diagnosed patients with lung adenocarcinoma were enrolled from the First Affiliated Hospital of Anhui Medical University. Next-generation sequencing (NGS) was conducted in these patients. Kruskal-Wallis test was used to calculate the difference in NSE levels between mutant and non-mutant group and the differences were compared between blood and tissue samples.

Results

Compared with patients with no gene mutation (15.4±7.8 mmol/L), the NSE levels in patients with gene mutations were remarkably increased in blood sample group (22.2±12.9 mmol/L) (P<0.05). Besides, the linear regression model was applied for analysis which further emphasized the close relationship between them. The area under the ROC curve (AUC) of NSE was 0.7300 [95% confidence interval (CI): 0.6059-0.8541] and optimal threshold was 18.5650 U/mL with a sensitivity of 87.50% and a specificity of 52.08%. In addition, NSE levels increased in blood sample group, suggesting that the occurrence of polygenic mutation with dismal prognosis, but no correlation was detected in tissue sample group.

Conclusions

This study elucidates the functional role of NSE, and findings in this study notably increase the gene detection efficiency for lung adenocarcinoma.

Prognostic value of PD-L1 expression in bronchopulmonary neuroendocrine tumours

Programmed death protein 1 (PD-1) and its ligand, PD-L1, have emerged as promising therapeutic targets for many types of cancer that overexpress PD-L1. However, data on PD-L1 expression levels in bronchopulmonary neuroendocrine neoplasms (BP-NEN) are limited and contradictory. In the present study, a total of 298 archived, formalin-fixed, paraffin-embedded BP-NEN samples from 97 patients diagnosed with typical carcinoid (TC), atypical carcinoid (AC), small cell lung cancer (SCLC), or large cell neuroendocrine carcinoma of the lung (LCNEC) were evaluated for PD-L1 expression by immunohistochemistry using the highly sensitive monoclonal anti-PD-L1 antibody 73-10. PD-L1 expression levels were semiquantitatively estimated by tumour grading. Of the 298 BP-NEN samples, 85% were positive for PD-L1 expression. PD-L1 immunostaining predominantly localized to the plasma membrane of both tumour cells and tumour-infiltrating immune cells. SCLC and LCNEC exhibited significantly higher PD-L1 expression levels than TC or AC. PD-L1 expression levels were also higher in patients with lymph node or distant metastases, in patients who smoked, and in patients who died during the follow-up period. Moreover, PD-L1 expression levels correlated positively with tumour grading, Ki-67 index and the expression of the chemokine receptor CXCR4 and negatively with the levels of somatostatin receptor 1 and chromogranin A. High tumour PD-L1 levels were associated with poor patient outcomes. In conclusion, PD-L1 expression is common in BP-NEN, increases with malignancy, and is associated with poor prognosis. Therefore, targeting the PD-1/PD-L1 axis could be a promising strategy for treating BP-NEN. PD-L1 may also represent a useful prognostic biomarker for this tumour entity.

Prognostic immunohistochemical markers for small cell lung cancer: A review

BACKGROUND

Small Cell Lung Cancer (SCLC) is one of the most aggressive thoracic malignancies and has been very challenging in developing personalized medicine. While immunohistochemistry (IHC) markers have established role in pathology diagnosis of SCLC, it is particularly important to apply early and simple methods to effectively determine the prognosis. This study aimed to review and identify prognostic protein markers that have potential to be incorporated into clinical care for SCLC.

METHODS

we systematically reviewed PubMed, Embase, Web of Science and Cochrane Library until October 19th, 2019 that reported prognostic IHC markers in SCLC. In this review, we focused on markers evaluated in at least two independent studies to compile the most forthcoming prognostic markers.

RESULTS

According to their function in the tumor, including proliferation-related markers, growth suppression-related markers, invasion- and metastasis-related markers, apoptosis-related markers, angiogenesis-related markers, immune regulation-related markers. Extensive reports into informative tables based on sufficiencies of evidence were summarized as some easy-to-use literature reservoirs for further referring.

CONCLUSIONS

Strong evidence supports that the 24 emerging markers or their combinations may be useful in predicting prognosis, helping personalized therapy decision-making for SCLC patients.

Gray E. Tumour PD-L1 Expression in Small-Cell Lung Cancer: A Systematic Review and Meta-Analysis

Antibodies against programmed death-1 (PD-1), and its ligand, (PD-L1) have been approved recently for the treatment of small-cell lung cancer (SCLC). Although there are previous reports that addressed PD-L1 detection on tumour cells in SCLC, there is no comprehensive meta-analysis on the prevalence of PD-L1 expression in SCLC. We performed a systematic search of the PubMed, Cochrane Library and EMBASE databases to assess reports on the prevalence of PD-L1 expression and the association between PD-L1 expression and overall survival (OS). This meta-analysis included 27 studies enrolling a total of 2792 patients. The pooled estimate of PD-L1 expression was 26.0% (95% CI 17.0–37.0), (22.0% after removing outlying studies). The effect size was significantly heterogeneous (I² = 97.4, 95% CI: 95.5–98.5, p < 0.0001).Positive PD-L1 expression was a favourable prognostic factor for SCLC but not statistically significant (HR = 0.86 (95% CI (0.49–1.50), p = 0.5880; I² = 88.7%, p < 0.0001). Begg’s funnel plots and Egger’s tests indicated no publication bias across included studies (p > 0.05). Overall, there is heterogeneity in the prevalence of PD-L1 expression in SCLC tumour cells across studies. This is significantly moderated by factors such as immunohistochemistry (IHC) evaluation cut-off values, and assessment of PD-L1 staining patterns as membranous and/or cytoplasmic. There is the need for large size, prospective and multicentre studies with well-defined protocols and endpoints to advance the clinical value of PD-L1 expression in SCLC.

Association between clinicopathological features and prognosis significance of PD-L1 expression in small cell lung cancer patients: a systemic review and meta-analysis

BACKGROUND

Programmed death ligand-1 (PD-L1) has been identified as an established biomarker for predicting response to immunotherapy in a variety types of cancer. However, the clinicopathological and prognostic significance of this protein in small cell lung cancer (SCLC) patients remains controversial.

METHODS

Eligible studies extracted from the databases of PubMed, MEDLINE, Embase, and CNKI databases were evaluated. Statistical analysis was performed using STATA 11.2 software.

RESULTS

A total of 483 PD-L1+ cases and 570 controls from 11 publications were extracted. Either overall analysis or subcategory analysis showed that no significant association between higher PD-L1 expression and gender (n=8, OR 1.08, 95% CI: 0.73-1.61, P=0.704, I²=0.0%), tumor stage (n=5, OR 0.71, 95% CI: 0.20-2.56, P=0.599, I²=86.5%), smoking status (n=4, OR 0.85, 95% CI: 0.41-1.73, P=0.646, I²=0.0%), and the level of serum lactate dehydrogenase (LDH) (n=4, OR 0.76, 95% CI: 0.48-1.20, P=0.241, I²= 21.6%). PD-L1 expression had no positive correlation with overall survival (OS) (n=11, HR 0.97, 95% CI: 0.61-1.56, P=0.904, I²= 83.2%) in overall analysis. However, the stratified analysis showed that increased expression of PD-L1 predicted a significantly better OS in monoclonal antibody (mAb) subgroup and Food and Drug Administration (FDA) approved antibody clone specification (22C3/28-8/SP142/SP263) subgroup without significant heterogeneity.

CONCLUSIONS

PD-L1 is not an important predictor of most clinicopathological features of SCLC patients, but it can predict an improved survival when using mAb or FDA approved clone specifications in IHC assays.

Prognostic and Clinicopathological Value of Programmed Cell Death Ligand1 Expression in Patients With Small Cell Lung Cancer: A Meta-Analysis

Background: Programmed death-ligand 1 (PD-L1) is an immune checkpoint molecule expressed by cancer cells. Previous studies have demonstrated the prognostic role of PD-L1 expression in patients with small cell lung cancer (SCLC), where the results were inconsistent. Therefore, we conducted a meta-analysis to identify the prognostic impact of PD-L1 on SCLC.

Methods: We searched the PubMed, Embase, ISI Web of Science, and Cochrane Library databases for articles published before and on March 2nd, 2020. Data of PD-L1 expression in tumor cells detected using immunohistochemistry methods were extracted for analysis. Pooled hazard ratios (HRs) with confidence intervals (CIs) and odds ratios (ORs) with 95% CIs were calculated to assess the correlations among PD-L1, overall survival (OS), and clinicopathological factors.

Results: Nine studies of 921 patients published between 2015 and 2019 were included in this meta-analysis. The pooled data (HR = 0.91, 95% CI = 0.46–1.80, p = 0.787) indicated that PD-L1 expression is not a significant predictor of poor OS. Moreover, the results also revealed that PD-L1 expression is not significantly associated with gender (OR = 1.12, 95% CI = 0.73–1.74, p = 0.601), age (OR = 1.15, 95% CI = 0.58–2.30, p = 0.683), pN stage (OR = 0.65, 95% CI = 0.24–1.72, p = 0.381), pT stage (OR = 1.16, 95% CI = 0.26–5.23, p = 0.847), serum lactate dehydrogenase level (OR = 1.06, 95% CI = 0.13–8.43, p = 0.958), or performance status (OR = 0.69, 95% CI = 0.24–1.95, p = 0.479). No significant publication bias was detected in this meta-analysis.

Conclusions: This meta-analysis suggests that PD-L1 expression is not a significant prognostic factor of poor survival in SCLC. Because of significant variations, high-quality studies are needed to validate our results.

PD-L1 Expression in Small Cell and Large Cell Neuroendocrine Carcinomas of Lung: an Immunohistochemical Study with Review of Literature

High-grade neuroendocrine tumors (HGNET) have distinctive tumor biology/behaviour. Newer modalities of treatment (immunotherapy) for them have been included in recent NCCN guidelines. Detection of programmed death receptor-ligand 1 (PD-L1) expression by immunohistochemistry have made easy identification of patients eligible for immunotherapy. We aimed to ascertain expression of PD-L1 on small cell and large cell neuroendocrine carcinomas of lung and review existing literature. Eighty-five cases of HGNET lung (primary/metastatic), were retrieved and reviewed. Immunostaining for PD-L1 using clone SP263 was done. Any amount/intensity of membranous staining of > = 1% tumor cells was cut-off for positivity. Previously published studies using Google and/Pubmed search engines were reviewed. Of 85 cases, 70 were small-cell lung cancer (SCLC), 11 large-cell neuroendocrine carcinoma (LCNEC) and 4 combined SCLC. Median age was 46.5 years with male preponderance. No PD-L1 expression was seen in 91.6% cases. The 7 positive cases were 4 LCNEC, 2 SCLC and 1 combined SCLC. The percentage positivity varied from 1-100%; lower percentage positivity was seen in SCLC. PD-L1 expression on immune cells was seen in 31.3% cases. Sixteen studies evaluating 1992 NET were found; E1L3N PD-L1 clone was commonly used clone. PD-L1 positivity was associated with better prognosis in most studies. There are only a few studies available in literature related to PDL1 expression in high grade neuroendocrine carcinomas of lung. In general, PD-L1 positivity is highly variable and seen in lower percentage of these tumors. With the recent approval of immunotherapy, biomarkers other than PD-L1 should also be investigated in these tumors.

Characterization of PD-L1 protein expression and CD8+ tumor-infiltrating lymphocyte density, and their associations with clinical outcome in small-cell lung cancer

Background

This study aimed to characterize programmed death ligand-1 (PD-L1) expression and CD8⁺ tumor-infiltrating lymphocytes (TILs) density, and their impact on survival in patients with surgically resected small-cell lung cancer (SCLC).

Methods

Fifty-six patients with surgically resected SCLC were included. PD-L1 protein expression and CD8⁺ TILs were tested by immunohistochemistry. A meta-analysis of 15 articles with 1,505 patients that investigated the prevalence and prognostic significance of PD-L1 expression in SCLC was conducted.

Results

Twenty-two (39.3%) patients had positive PD-L1 protein expression and 42 (75.0%) had high CD8⁺ TILs density. PD-L1 expression level was not associated with CD8⁺ TILs density (P=0.528). No any association between clinicopathological features and PD-L1 expression level or CD8⁺ TILs density was observed. Positive PD-L1 expression [hazard ratio (HR) =0.374, P=0.002] and high CD8⁺ TILs density (HR =0.429, P=0.008) were independently associated with significantly longer overall survival (OS), which remain the statistical significance in multivariate analyses (P=0.007, P=0.002; respectively). Meta-analysis showed that the prevalence of positive PD-L1 expression was 0.35 [95% confidence interval (CI), 0.22-0.48] and positive PD-L1 expression was correlated with markedly longer OS (HR =0.61; 95% CI, 0.31-0.91) in patients with SCLC.

Conclusions

The prevalence of PD-L1 expression in surgically resected SCLC is lower than that published for NSCLC. There was no association between PD-L1 expression or CD8⁺ TILs density and clinicopathological parameters. PD-L1 expression and CD8⁺ TILs density was independently correlated with better outcome in patients with SCLC.

Comparing three different anti-PD-L1 antibodies for immunohistochemical evaluation of small cell lung cancer

OBJECTIVE

Small cell lung cancer (SCLC), which accounts for approximately 15% of all lung cancer cases, has high initial sensitivity to chemotherapy. However, clinical outcomes have not improved in the past two decades. Therefore, novel biomarkers are needed to prolong survival in patients with advanced SCLC.

MATERIAL AND METHODS

In this retrospective study, we assessed 44 patients with SCLC who underwent first-line or adjuvant chemotherapy. We analyzed PD-L1 expression in SCLC tumors using three specific anti-PD-L1 antibody clones (28-8, 22C3, and SP263) and assessed their correlation with clinical profiles.

RESULTS

Each clone yielded PD-L1 positivity as follows: 10 cases with 28-8, eight cases with 22C3, and six cases with SP263. Eleven patients tested positive with at least one of the three anti-PD-L1 antibodies, and 33 patients tested negative with all anti-PD-L1 antibodies. Serum neuron-specific enolase levels at diagnosis were significantly higher in negative tumors than in positive tumors with the 28-8 clone (p = 0.036) and, similarly, tended to be higher in negative tumors with the 22C3 and SP263 clones.

CONCLUSION

These observations suggest that PD-L1 is detected in SCLC tumors at a similar rate and with similar clinical correlates when detected using any of these three anti-PD-L1 clones. Further large-scale investigations are warranted to reveal the roles of PD-L1 expression in patients with SCLC.

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.

Fluorodeoxyglucose uptake is associated with low tumor-infiltrating lymphocyte levels in patients with small cell lung cancer

OBJECTIVES

Positron emission tomography (PET) using 2-deoxy-2-[¹⁸F] fluoro-D-glucose (¹⁸F-FDG) is a clinically useful modality for cancer evaluation. The mechanism of ¹⁸F-FDG uptake within cancer cells involves the glucose transporter 1 (GLUT1) and hypoxia-inducible factor-1 α (HIF-1α). Although recent research has shown its clinical efficacy in small-cell lung cancer (SCLC), no suitable biomarker has been identified. We conducted a clinicopathological study to examine the relationship between tumor immunity and ¹⁸F-FDG uptake in patients with SCLC.

MATERIALS AND METHODS

Tumor sections were stained by immunohistochemistry for GLUT1, HIF-1α, PD-L1, CD4, CD8, and Foxp3. The relationship between clinicopathological features and ¹⁸F-FDG uptake was analyzed. Student's t-test, χ2 test, non-parametric Spearman's rank test, and Kaplan-Meier method were used to evaluate associations between the variables.

RESULTS

A total of 98 patients 78 men and 20 women who underwent ¹⁸F-FDG PET, were enrolled in this study. PD-L1 was expressed in 36.7% (36/98) of all patients; this was significantly associated with GLUT1 expression (p = 0.04). The accumulation of ¹⁸F-FDG was significantly higher in patients with low CD8 and CD4 TILs than in those with high TILs (p = 0.03 and p = 0.01, respectively). The uptake of ¹⁸F-FDG was not significantly associated with the expression of either Foxp3 or PD-L1. Multivariate analysis demonstrated that advanced stage, poor ECOG-PS, and high SUV_max were independent predictors of poor OS. Among patients with limited-stage disease, multivariate analysis confirmed high PD-L1 expression and a high SUV_max to be independent predictors of poor OS. However, only ECOG-PS was found to be an independent predictor of poor OS among patients with extensive-stage tumors.

CONCLUSION

High SUV_max on ¹⁸F-FDG-PET is correlated with low expression of CD8(+) and CD4(+) TILs, but is an independent prognostic factor for OS, particularly in those with limited disease. Further studies are warranted to validate our findings.

Neoadjuvant anti-programmed Death-1 immunotherapy by Pembrolizumab in resectable nodal positive stage II/IIIa non-small-cell lung cancer (NSCLC): the NEOMUN trial

Background

Immunotherapies targeting the PD1/PD-L1 pathway have had a large impact on the treatment of advanced NSCLC. Concerning multimodality tumor therapy, only few trials until today have been performed investigating neoadjuvant treatment with anti PD-1 immunotherapy prior to curative intent surgery. Aim of the NEOMUN investigator initiated trial (EudraCT-Number: 2017–000105-20; ClinicalTrials.gov Identifier: NCT03197467) is to assess feasibility and safety of pre-surgical anti PD-1 treatment in order to improve long term survival.

Methods

The study is designed as an open-label, single arm, prospective, monocenter, phase II study including 30 patients with NSCLC stage II/IIIA suitable for curative intent surgery. Investigational drug is Pembrolizumab. After 2 cycles of immunotherapy (à 200 mg q3w i.v.), tumor resection with lobectomy or bilobectomy will be performed. Primary objectives are to assess the feasibility and safety of a neoadjuvant immunotherapy and to assess antitumor activity of Pembrolizumab with regard to clinical and pathological tumor response. Secondary objective is disease free and overall survival. Exploratory objective is to analyze potential predictive biomarkers and to evaluate the therapeutic efficacy of Pembrolizumab by extended immune cell and cytokine analysis of tumor tissue.

The study protocol was approved by the local ethics committee and the federal authority. Start of patient enrollment is scheduled for June 2018.

Discussion

The NEOMUN trial will be one of the first clinical trials investigating a multimodal treatment strategy including neoadjuvant immunotherapy using Pembrolizumab as an investigational drug. Assessing the safety and therapeutic potential of neoadjuvant immunotherapy in connection with lung surgery will be of great interest for thoracic surgeons.

Trial registration

Prospectively, the NEOMUN study has been registered on www.clinicaltrials.gov; NCT03197467 (first post: June 23rd, 2017).

Significance of PD-L1 clones and C-MET expression in hepatocellular carcinoma

Programmed cell death ligand 1 (PD-L1) is an essential immune checkpoint protein implicated in immune evasion by malignant tumors. Overexpression of programmed cell death protein 1 (PD-1) and its ligand PD-L1 is associated with poor prognosis in various types of cancer. Recently, multiple advances have occurred in the area of cancer immunotherapy. Inhibiting the ligation of PD-1 by PD-L1 has been the major focus of anti-tumor immunotherapy. In diagnostic pathology, it has become crucial to detect PD-L1⁺ tumor cases using a validated immunohistochemistry (IHC) approach. Preliminary data demonstrate that C-MET promotes survival of some (e.g., renal) cancer types through regulation of PD-L1. However, C-MET expression, and its association with PD-L1, has not been well-characterized in the context of hepatocellular carcinoma (HCC), and no anti-HCC immunotherapy is currently available in Korea. Therefore, it is crucial to investigate the expression of C-MET and PD-L1, and their association with clinicopathologic factors, to facilitate the development of targeted treatments for HCC. PD-L1 expression was examined in tumor cells (TC) and immune cells (IC) of 70 patient-derived HCC specimens using IHC. Two anti-PD-L1 monoclonal antibodies (MAbs), SP263 and SP142, were utilized. Additionally, TC C-MET expression was assessed. Correlations between PD-L1 expression (as identified by both MAbs), C-MET expression and clinicopathologic factors were assessed. More PD-L1⁺ cases were identified via SP263 than via SP142 when assessing both TC and IC; in the former group, SP236 identified 14/70 positive cases, while SP142 identified only 2/70. In the latter group, SP236 identified 49/70 positive cases, while SP142 identified 30/70. Both MAbs demonstrated a higher frequency of PD-L1 expression by IC than TC. The Edmondson-Steiner grade statistically correlated with a higher frequency of SP236-detected TC PD-L1 expression. C-MET was significantly associated with advanced tumor size and was positively correlated with SP263-detected PD-L1 expression in TC. These results suggest that C-MET may serve a role in regulating PD-L1 expression in HCC. Furthermore, while SP263 generally exhibited a higher sensitivity for PD-L1 detection, concordance in PD-L1⁺ case detection between the two different MAbs was generally good. These background data may be helpful in the development of targeted anti-HCC immunotherapy focused on PD-L1 or C-MET, and in evaluating selection criteria for target populations best suited to such treatments.

Immunotherapy for small cell lung cancer: mechanisms of resistance

INTRODUCTION

Small cell lung cancer (SCLC) is a highly malignant disease with a dismal prognosis that is currently being tested for theclinical activity of checkpoint inhibitors. SCLC is associated with smoking and exhibits a high mutational burden. However, low expression of PD-L1 and MHC antigens, as well low levels of immune cell infiltration and rapid tumor progress seems to limit the efficacy of anticancer immunity. Nevertheless, long-term survival was reported from studies using anti-PD-1/PD-L1 and CTLA-4 agents.

AREAS COVERED

Data of clinical trials of checkpoint inhibitors in SCLC show lower success rates compared to NSCLC. The mechanisms of resistance to immunotherapy are discussed for their relevance to SCLC patients.

EXPERT OPINION

Although some factors, such as a high mutation rate, favor immunotherapy for SCLC patients, downregulation of MHC class I, low expression of PD-L1, poor tumor infiltration by effector T cells, presence of myeloid-derived suppressor cells as well as regulatory T lymphocytes counteract the immune system activation by checkpoint inhibitors. Furthermore, this tumor develops avascular regions which have immunosuppressive effects and restrict access of lymphocytes and antibodies. In conclusion, immunotherapy in SCLC is effective in highly selected patients with good performance status and special and unknown preconditions contributing to long-lasting responses.

Surgical Resection of SCLC: Prognostic Factors and the Tumor Microenvironment

INTRODUCTION

Surgery in SCLC is limited to very early stages, but several reports suggest a potential broader role. Little is known of the influence of microenvironment on the biology of SCLC.

METHODS

We assessed the clinical prognostic factors in a large series of resected SCLC patients. The prognostic value of programmed cell death ligand 1 (PD-L1) expression in tumor cells and tumor infiltrating lymphocytes (TILs) and the percentage of CD3-, CD20-, CD45- and CD68-positive cells, were also investigated.

RESULTS

Two hundred five SCLC cases were resected between 2005 and 2015 and the median follow-up was 29 months (range: 2 to 135 months). Median survival of all patients was 69 months, and 5-year survival rates were 63.8%, 65.5%, 34.9%, and 0% for pathologic stages I, II, III, and IV, respectively. By multivariate analysis complete resection, cigarette index, lymph node metastatic rate, percentage of CD3-positive cells, PD-L1 expression in tumor cells, and TILs were independent prognostic factors. High PD-L1 expression was present in 3.2% and 33.5% of all tumor samples in tumor cells and TILs, respectively. High PD-L1 expression in tumor cells or TILs correlated with shorter survival, whereas high expression of CD3, CD20, and CD45 correlated with better survival.

CONCLUSIONS

Resected stage II SCLC patients have similar survival as stage I, suggesting that surgery could be extended to patients with hilar lymph node involvement. Survival was better in tumors with a higher percentage of T cells and B cells, whereas PD-L1 expression in tumor cells and TILs correlated with worse survival, which suggests a potential role of immunotherapy in resected SCLC.

Current Treatment Options in Gastroenteropancreatic Neuroendocrine Carcinoma

Poorly differentiated gastroenteropancreatic neuroendocrine carcinomas (GEPNECs) are a rare neoplasm with a bleak prognosis. Currently there are little prospective data available for optimal treatment. This review discusses the current available regimens and the future direction for the treatment of GEPNECs. Treatment plans for GEPNECs are often adapted from those devised for small cell lung cancer; however, differences in these malignancies exist, and GEPNECs require their own treatment paradigms. As such, current first-line treatment for GEPNECs is platinum-based chemotherapy with etoposide. Studies show that response rate and overall survival remain comparable between cisplatin and carboplatin versus etoposide and irinotecan; however, prognosis remains poor, and more efficacious therapy is needed to treat this malignancy. Additional first-line and second-line treatment options beyond platinum-based chemotherapy have also been investigated and may offer further treatment options, but again with suboptimal outcomes. Recent U.S. Food and Drug Administration approval of peptide receptor radionuclide therapy in low- and intermediate-grade neuroendocrine tumors may open the door for further research in its usefulness in GEPNECs. Additionally, the availability of checkpoint inhibitors lends promise to the treatment of GEPNECs. This review highlights the lack of large, prospective studies that focus on the treatment of GEPNECs. There is a need for randomized control trials to elucidate optimal treatment regimens specific to this malignancy. IMPLICATIONS FOR PRACTICE: There are limited data available for the treatment of poorly differentiated gastroenteropancreatic neuroendocrine carcinomas (GEPNECs) because of the rarity of this malignancy. Much of the treatment regimens used in practice today come from research in small cell lung cancer. Given the poor prognosis of GEPNECs, it is necessary to have treatment paradigms specific to this malignancy. The aim of this literature review is to summarize the available first- and second-line GEPNEC therapy, outline future treatments, and highlight the vast gap in the literature.

Programmed death-ligand 1 positivity can predict improved survival and a lower risk of brain metastasis in patients with resectable small cell lung cancer

The present study aimed to investigate the expression of programmed death-ligand 1 (PD-L1) in resectable small cell lung cancer (SCLC) and investigate its predictive value for survival and brain metastasis (BM). Postoperative SCLC specimens were immunostained with the SP142 antibody against PD-L1. Positive PD-L1 expression was defined as PD-L1 expression in ≥5% of tumor cells. A total of 80 patients were recruited between January 2010 and December 2012. PD-L1 was expressed in 65.0% (52/80) of all patients and 59.3% (16/27) of patients with BM. The median survival time (MST) was longer in the PD-L1(+) group (46.4 vs. 28.5 months, P=0.002). There was no significant difference in the MST between patients with PD-L1(+) or (−) BM (P=0.55). The 3-year risk of BM in the PD-L1(+) group was lower than that in the PD-L1(−) group (24.1 vs. 48.4%, P=0.046). PD-L1 was an independent factor for overall survival (OS) [hazard ratio (HR)=0.485, P=0.011] and BM (HR=0.335, P=0.024). The present study concludes that PD-L1 is commonly expressed in SCLC and is associated with OS and BM.

High level of programmed death ligand 1 (PD-L1) predicts longer survival in patients with resectable small cell lung cancer

The purpose of this study was to investigate the association between the expression of programmed cell death ligand 1 (PD-L1) and the survival of patients with small cell lung cancer (SCLC) who had undergone complete resection. Formalin-fixed, paraffin-embedded tumor tissue samples from 61 patients with resected SCLC were stained with an anti-PD-L1 antibody (SP142) by immunohistochemistry (IHC) and scored according to staining intensity and the percentage of tumor cells staining positive for PD-L1. The PD-L1 positive threshold in tumor cells was defined as ≥ 5%. The percentage of positive PD-L1 staining in all SCLC specimens was 44.3% (27/61). The median survival time of patients with PD-L1-positive tumors was significantly longer than those with PD-L1-negative tumors (not reached vs. 34 months, P = 0.032). Multivariate analysis indicated that postoperative chemotherapy (HR = 0.322, P = 0.023) and PD-L1 expression ≥ 5% (HR = 0.253, P = 0.008) were independent prognostic factors for overall survival. The results suggest that PD-L1 expression is readily detectable in the tumor tissues of SCLC, and that PD-L1 expression can predict the survival of these patients.

Association of tumor TROP2 expression with prognosis varies among lung cancer subtypes

TROP2 is a transmembrane glycoprotein that is overexpressed in various cancers. Emerging evidence suggests that TROP2-targeting therapies are efficacious and safe in patients with multiple prior treatments. TROP2 is a promising target for lung cancer treatment; however, little is known regarding the association of TROP2 expression with clinicopathological/molecular features, including prognosis, in lung cancer. We examined consecutive cases of adenocarcinoma, squamous cell carcinoma (SqCC), and high-grade neuroendocrine tumor (HGNET) for the membranous expression of TROP2 using immunohistochemistry. High TROP2 expression was observed in 64% (172/270) of adenocarcinomas, 75% (150/201) of SqCCs, and 18% (21/115) of HGNETs. Intriguingly, the association of TROP2 expression with mortality was dependent on the lung cancer subtype. High TROP2 expression was associated with higher lung cancer-specific mortality in adenocarcinomas [univariable hazard ratio (HR) = 1.60, 95% confidence interval (CI) = 1.07–2.44, P = 0.022)], but not in SqCCs (univariable HR = 0.79, 95% CI = 0.35–1.94, P = 0.79). In HGNETs, high TROP2 expression was associated with lower lung cancer-specific mortality in both univariable and multivariable analyses (multivariable HR = 0.13, 95% CI = 0.020–0.44, P = 0.0003). Our results suggest a differential role for TROP2 in different lung cancer subtypes.

Characterization of PD-L1 expression in Chinese non-small cell lung cancer patients with PTEN expression as a means for tissue quality screening

The goal of this study is to evaluate PD-L1 prevalence and its association with major clinical characteristics in Chinese non-small cell lung cancer (NSCLC) patients to inform the clinical development of anti-PD1/PD-L1 agents in this population. We used phosphatase and tensin homolog (PTEN) expression through IHC as a surrogate tissue quality marker to screen surgical NSCLC samples in tissue microarray (TMA; 172 cases) or whole-section (268 cases) format. The samples were then analyzed with a clinically validated PD-L1 IHC assay. The results were correlated with baseline characteristics and clinical outcomes. PTEN IHC showed that 108 TMA samples and 105 whole-section samples qualified for PD-L1 IHC. With a clinically relevant cutoff, 41.7% of the TMA samples were PD-L1 positive. PD-L1 level was much lower in EGFR-mutant patients and seemed to be a favorable prognostic factor for both overall survival (OS) and recurrence-free survival (RFS). These findings were confirmed in the whole-section samples except that their survival data were not mature enough for correlation analysis. In summary, PD-L1 expression was detected in approximately 40% of PTEN-qualified Chinese NSCLC samples, negatively correlated with EGFR mutation and seemed to be a favorable prognostic factor for both OS and RFS. Notably, the different results from PTEN-qualified and PTEN-disqualified samples underscore the importance of tissue quality control prior to biomarker testing.

PD-L1 expression in large cell neuroendocrine carcinoma of the lung

OBJECTIVES

Large cell neuroendocrine carcinoma of the lung (LCNEC) is associated with an unfavorable prognosis and only few patients are eligible for surgery. In most patients, chemotherapy is recommended alone or in addition to resection. Novel immunotherapies blocking the PD-L1 pathway have been introduced into therapeutic regimens for NSCLC with great success. In order to evaluate a possible efficacy of an anti-PD-L1 therapy, we analyzed the frequency of PD-L1 expression in LCNEC.

MATERIAL AND METHODS

We retrospectively reviewed data from 76 patients with LCNEC treated in our institution between 1998 and 2010. The expression of PD-L1 was examined on the tumor cells and the tumor surrounding tissue by immunohistochemistry. An expression of >1% was considered as positive. Statistical analysis was performed to determine significant predictors for survival.

RESULTS

56 of 76 patients with LCNEC were treated with a potentially therapeutic surgical approach. Tumor-specific survival (TSS) of the entire cohort was 29% at five years. 17 patients (22.3%) had PD-L1 positive tumors and 12 of these had no additional PD-L1 expression in the adjacent immune cell infiltrate. Tumor-flanking immune cells were found PD-L1 positive 28 patients; 16 of these had no additional expression on the tumor cells. The most considerable difference in survival was found when comparing patients with isolated PD-L1 expression on tumor cells and PD-L1 negative immune cell infiltrate to their counterpart (positive immune-cell infiltrate and PD-L1 negative tumor cell surface; 5-year TSS: 0% vs. 60%; p < 0.017).

CONCLUSION

PD-L1 expression in LCNEC was associated with poorer survival whereas PD-L1 expression in the tumor microenvironment seemed to have a beneficial effect. Therapeutic approaches have to be evaluated in future.

Development of diagnostic model of lung cancer based on multiple tumor markers and data mining

Objective

To develop early intelligent discriminative model of lung cancer and evaluate the efficiency of diagnosis value.

Methods

Based on the genetic polymorphism profile of CYP1A1-rs1048943, GSTM1, mEH-rs1051740, XRCC1-rs1799782 and XRCC1-rs25489 and the methylations of p16 and RASSF1A gene, and the length of telomere in the peripheral blood from 200 lung cancer patients and 200 health persons, the discriminative model was established through decision tree and ANN technique.

Results

ACU of the discriminative model based on multiple tumour markers increased by about 10%; The accuracy rate of decision tree model and ANN model for testing set were 93.00% and 89.62% respectively. The ROC analysis showed the decision tree model’s AUC is 0.929 (0.894∼0.964), the ANN model’s AUC is 0.894 (0.853∼0.935). However, the classify accuracy rate and AUC of Fisher discriminatory analysis model are all about 0.7.

Conclusion

The early intelligent discriminative model of lung cancer based on multiple tumor markers and data mining techniques has a higher accuracy rate and might be useful for early diagnosis of lung 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.

c-Met in chromophobe renal cell carcinoma

c-Met plays a role as a prognostic marker in clear cell renal cell carcinoma. In addition, recently the tyrosine kinase inhibitor cabozantinib targeting c-Met was approved for the treatment of advanced renal cell carcinoma (RCC). In contrast to clear cell RCC, little is known about c-Met expression patterns in rarer RCC subtypes. The aim of this study was to evaluate the prevalence, distribution and prognostic impact of c-Met expression on chromophobe (ch)RCC. Patients who underwent renal surgery due to chRCC were retrospectively evaluated. Tumor specimens were analyzed for c-Met expression by immunohistochemistry. Expression data were associated with clinicopathological parameters including patient survival. Eighty-one chRCC patients were eligible for analysis. Twenty-four (29.6%) patients showed a high c-Met expression (c-Met^high, staining intensity higher than median). Our results showed an association between c-Met^high expression and the existence of lymph node metastasis (p = 0.007). No further significant clinicopathological associations with c-Met were identified, also regarding c-Met expression and overall survival. In conclusion, to our knowledge this is the first study evaluating the prognostic impact of c-Met in a considerably large cohort of chRCC. High c-Met expression is associated with the occurrence of lymph node metastasis. This indicates that c-Met might be implicated into metastatic progression in chRCC.