The Significance of the PD-L1 Expression in Non-Small-Cell Lung Cancer: Trenchant Double Swords as Predictive and Prognostic Markers

Comprehensive molecular analysis of driver mutations in non-small cell lung carcinomas and its correlation with PD-L1 expression, An Indian perspective

BACKGROUND

The understanding of molecular mechanisms involved in non-small cell lung carcinoma (NSCLC) has revolutionized significantly in the recent years. These have helped to develop personalized management strategies by identifying specific molecular alterations such as mutations in EGFR, ROS1, BRAF, ERBB2, MET, ALK, and KRAS genes. These mutations are targetable ensuring a better clinical outcome. Next-generation sequencing (NGS) methodology is the recommended technique for the identification of driver mutations in the five hot-spot genes (EGFR, ALK, ROS1, MET, and BRAF) involved in the NSCLC. NGS has numerous advantages including multiplexing, tissue conservation, identification of rare and novel variants, and reduced cost over the sequential single gene testing. Herein, we sought to demonstrate the mutational profile in NSCLC and their clinicopathologic correlation in a contemporary cohort of Indian NSCLC patients. Additionally, we studied the correlation of oncogenic driver mutations with PD-L1 status in these patients.

MATERIALS AND METHODS

Five fifty-two stage IV NSCLC patients (adenocarcinoma=490; squamous cell carcinoma=51; adenosquamous carcinoma=5; large cell carcinoma=2; sarcomatoid carcinoma=3; spindle cell carcinoma=1) underwent broad molecular profiling by a custom-made, targeted DNA- and RNA-based five hot-spot genes lung cancer panel (EGFR, ALK, ROS1, BRAF, and MET), compatible with the NGS Ion S5 system. The mutations were correlated with the clinicopathologic characteristics. Additionally, PD-L1 expression status, available on 252 tumors, was correlated with the oncogenic drivers.

RESULTS

Validation of the 5 gene panel yielded the following results: a) specificity of 99.74%; b) sensitivity of 100% for single nucleotide variants (SNVs) (>5% variant allele frequency, VAF), indels (>10% VAF) and fusions; c) 100% intra- and inter-run reproducibility; d) 88% inter-laboratory agreement. Validated panel was then used to analyze clinical samples. Sixty percentage tumors harbored either one (54.71%) or multiple (3.26%) mutations. EGFR and BRAF V600E mutations, ALK and ROS1 rearrangements, and MET exon 14 skipping mutation were observed in 38.41% (n = 212) and 2.72% (n = 15) patients, 12.14% (n = 67) and 3.62% (n = 20) patients, and 1.09% (n = 6) patients, respectively. EGFR exon 19 deletion accounted for 52.83% of all mutations, followed by L858R (35.85%), T790M (5.19%), exon 20 insertions (6.6%), and other rare mutations (G719X, L861Q, S768I) (9.91%). Concurrent EGFR with ALK, EGFR with ROS1, EGFR with MET, and EGFR with BRAF were observed in 10, 4, 1, and 3 patients, respectively. PD-L1 was expressed in 134 patients (53.2%). Exon 19 deletion was more prevalent in PD-L1 negative tumors whereas exon 21 substitution (L858R) was seen more in PD-L1 positive tumors.

CONCLUSIONS

This is one of the largest cohorts of NSCLC for comprehensive targeted mutational profiling and correlation with the PD-L1 expression. The mutations are more prevalent in non-smoker females for all genes, except ALK (non-smoker males). MET and BRAF mutations are more common in elderly population whereas EGFR mutations, and ALK and ROS1 genes rearrangements are more prevalent in younger population. The most common histopathologic subtype/feature associated with various mutations was as follows: acinar with EGFR, solid with ALK, macronucleoli with ROS1, signet ring with MET, and micropapillary with BRAF.

Correlation of Programmed Death-Ligand 1 Expression With Lung Adenocarcinoma Histologic and Molecular Subgroups in Primary and Metastatic Sites

Programmed death-ligand 1 (PD-L1) expression in terms of the tumor proportion score (TPS) is the main predictive biomarker approved for immunotherapy against lung nonsmall cell carcinoma. Although some studies have explored the associations between histology and PD-L1 expression in pulmonary adenocarcinoma, they have been limited in sample size and/or extent of examined histologic variables, which may have resulted in conflicting information. In this observational retrospective study, we identified primary and metastatic lung adenocarcinoma cases in the span of 5 years and tabulated the detailed histopathologic features, including pathological stage, tumor growth pattern, tumor grade, lymphovascular and pleural invasion, molecular alterations, and the associated PD-L1 expression for each case. Statistical analyses were performed to detect associations between PD-L1 and these features. Among 1658 cases, 643 were primary tumor resections, 751 were primary tumor biopsies, and 264 were metastatic site biopsies or resections. Higher TPS significantly correlated with high-grade growth patterns, grade 3 tumors, higher T and N stage, presence of lymphovascular invasion, and presence of MET and TP53 alterations, whereas lower TPS correlated with lower-grade tumors and presence of EGFR alterations. There was no difference in PD-L1 expression in matched primary and metastases, although higher TPS was observed in metastatic tumors due to the presence of high-grade patterns in these specimens. TPS showed a strong association with a histologic pattern. Higher-grade tumors had higher TPS, which is also associated with more aggressive histologic features. Tumor grade should be kept in mind when selecting cases and blocks for PD-L1 testing.

The Efficacy of Tumor Mutation Burden as a Biomarker of Response to Immune Checkpoint Inhibitors

Cancer is one of the leading causes of death in the world; therefore, extensive research has been dedicated to exploring potential therapeutics, including immune checkpoint inhibitors (ICIs). Initially, programmed-death ligand-1 was the biomarker utilized to predict the efficacy of ICIs. However, its heterogeneous expression in the tumor microenvironment, which is critical to cancer progression, promoted the exploration of the tumor mutation burden (TMB). Research in various cancers, such as melanoma and lung cancer, has shown an association between high TMB and response to ICIs, increasing its predictive value. However, the TMB has failed to predict ICI response in numerous other cancers. Therefore, future research is needed to analyze the variations between cancer types and establish TMB cutoffs in order to create a more standardized methodology for using the TMB clinically. In this review, we aim to explore current research on the efficacy of the TMB as a biomarker, discuss current approaches to overcoming immunoresistance to ICIs, and highlight new trends in the field such as liquid biopsies, next generation sequencing, chimeric antigen receptor T-cell therapy, and personalized tumor vaccines.

Predictive biomarkers for PD-1/PD-L1 checkpoint inhibitor response in NSCLC: an analysis of clinical trial and real-world data

BACKGROUND

Many biomarkers have been proposed to be predictive of response to anti-programmed cell death protein-1 (PD-1)/anti-programmed death ligand-1 (PD-L1) checkpoint inhibitors (CPI). However, conflicting observations and lack of consensus call for an assessment of their clinical utility in a large data set. Using a combined data set of clinical trials and real-world data, we assessed the predictive and prognostic utility of biomarkers for clinical outcome of CPI in non-small cell lung cancer (NSCLC).

METHODS

Retrospective cohort study using 24,152 patients selected from 71,850 patients with advanced NSCLC from electronic health records and 9 Roche atezolizumab trials. Patients were stratified into high and low biomarker groups. Correlation with treatment outcome in the different biomarker groups was investigated and compared between patients treated with CPI versus chemotherapy. Durable response was defined as having complete response/partial response without progression during the study period of 270 days.

RESULTS

Standard blood analytes (eg, albumin and lymphocyte) were just prognostic, having correlation with clinical outcome irrespective of treatment type. High expression of PD-L1 on tumors (≥50% tumor cell staining) were specifically associated with response to CPI (OR 0.20; 95% CI 0.13 to 0.30; p<0.001). The association was stronger in patients with non-squamous than squamous histology, with smoking history than non-smokers, and with prior chemotherapy than first-line CPI. Higher tumor mutational burden (TMB) (≥10.44 mut/Mb) was also specifically associated with durable response to CPI (OR=0.40; 95% CI 0.29 to 0.54; p<0.001). The combination of high TMB and PD-L1 expression was the strongest predictor of durable response to CPI (OR=0.04; 95% CI 0.00 to 0.18; p<0.001). There was no significant association between PD-L1 or TMB levels with response to chemotherapy, suggesting a CPI-specific predictive effect.

CONCLUSIONS

Standard blood analytes had just prognostic utility, whereas tumor PD-L1 and TMB specifically predicted response to CPI in NSCLC. The combined high TMB and PD-L1 expression was the strongest predictor of durable response. PD-L1 was also a stronger predictor in patients with non-squamous histology, smoking history or prior chemotherapy.

Early recurrence factors in patients with stage III non-small cell lung cancer treated with concurrent chemoradiotherapy

BACKGROUND

The clinical characteristics and risk factors for cancer recurrence have not been well evaluated regarding early recurrence in patients with unresectable locally advanced non-small cell lung cancer (LA-NSCLC) who receive concurrent chemoradiotherapy (CRT). The aim of this study was to determine the clinical characteristics and risk factors of patients with stage III unresectable LA-NSCLC treated with CRT who developed early recurrence.

METHODS

We retrospectively reviewed the clinical records of 46 patients diagnosed with stage III unresectable LA-NSCLC treated with CRT at our center between July 2012 and July 2021. A tumor proportion score (TPS) < 50% was defined as "low expression" and a TPS > 50% was defined as "high expression."

RESULTS

A total of 17 (37.0%) patients had a confirmed recurrence within 1 year of treatment. More patients had a lower body mass index in the early recurrence group than in the later recurrence group (p = 0.038). A higher number of patients in the late recurrence group underwent surgery after CRT (p = 0.036). Patients with a higher TPS were more likely to experience late recurrence than early recurrence (p = 0.001), whereas more patients with stage N3 disease were in the early recurrence group (p = 0.011). Multivariate analysis identified lower TPS expression as an independent risk factor for early recurrence after CRT. Overall survival was prolonged in the late recurrence group (p < 0.001).

CONCLUSIONS

A lower TPS may be a predictor of early recurrence after CRT in patients with LA-NSCLC. These patients should be closely monitored for post-treatment recurrence.

NUF2 Is a Potential Immunological and Prognostic Marker for Non-Small-Cell Lung Cancer

Background

Globally, non-small-cell lung cancer (NSCLC) is one of the most prevalent tumors. Various studies have investigated its etiology, but the molecular mechanism of NSCLC has not been elucidated.

Methods

The GSE19804, GSE118370, GSE19188, GSE27262, and GSE33532 microarray datasets were obtained from the Gene Expression Omnibus (GEO) database for the identification of genes involved in NSCLC development as well as progression. Then, the identified differentially expressed genes (DEGs) were subjected to functional enrichment analyses. The protein-protein interaction (PPI) network was built after which module analysis was conducted via the Search Tool for Retrieval of Interacting Genes/Proteins (STRING) and Cytoscape. There were 562 DEGs: 98 downregulated genes and 464 upregulated. These DEGs were established to be enriched in p53 signaling pathway, transendothelial leukocyte migration, cell adhesion molecules, contractions of vascular smooth muscles, coagulation and complement cascades, and axon guidance. Assessment of tumor immunity was performed to determine the roles of hub genes.

Results

There were 562 dysregulated genes, while 12 genes were hub genes. NUF2 was established to be a candidate immunotherapeutic target with potential clinical implications. The 12 hub genes were highly enriched in the p53 signaling pathway, the cell cycle, progesterone-associated oocyte maturation, cellular senescence, and oocyte meiosis. Survival analysis showed that NUF2 is associated with NSCLC occurrence, invasion, and recurrence.

Conclusion

The NUF2 gene discovered in this study helps us clarify the pathomechanisms of NSCLC occurrence as well as progression and provides a potential diagnostic and therapeutic target for NSCLC.

Prognostic value of immunotherapy-induced organ inflammation assessed on 18FDG PET in patients with metastatic non-small cell lung cancer

PURPOSE

We evaluated the prognostic value of immunotherapy-induced organ inflammation observed on ¹⁸FDG PET in patients with non-small cell lung cancer (NSCLC) treated with immune checkpoint inhibitors (ICPIs).

METHODS

Data from patients with IIIB/IV NSCLC included in two different prospective trials were analyzed. ¹⁸FDG PET/CT exams were performed at baseline (PET_Baseline) and repeated after 7-8 weeks (PET_Interim1) and 12-16 weeks (PET_Interim2) of treatment, using iPERCIST for tumor response evaluation. The occurrence of abnormal organ ¹⁸FDG uptake, deemed to be due to ICPI-related organ inflammation, was collected.

RESULTS

Exploratory cohort (Nice, France): PET_Interim1 and PET_Interim2 revealed the occurrence of at least one ICPI-induced organ inflammation in 72.8% of patients, including midgut/hindgut inflammation (33.7%), gastritis (21.7%), thyroiditis (18.5%), pneumonitis (17.4%), and other organ inflammations (9.8%). iPERCIST tumor response was associated with improved progression-free survival (p < 0.001). iPERCIST tumor response and immuno-induced gastritis assessed on PET were both associated with improved overall survival (OS) (p < 0.001 and p = 0.032). Combining these two independent variables, we built a model predicting patients' 2-year OS with a sensitivity of 80.3% and a specificity of 69.2% (AUC = 72.7). Validation cohort (Genova, Italy): Immuno-induced gastritis (19.6% of patients) was associated with improved OS (p = 0.04). The model built previously predicted 2-year OS with a sensitivity and specificity of 72.0% and 63.6% (AUC = 70.7) and 3-year OS with a sensitivity and specificity of 69.2% and 80.0% (AUC = 78.2).

CONCLUSION

Immuno-induced gastritis revealed by early interim ¹⁸FDG PET in around 20% of patients with NSCLC treated with ICPI is a novel and reproducible imaging biomarker of improved OS.

The effect of neoadjuvant therapy on PD-L1 expression and CD8+lymphocyte density in non-small cell lung cancer

PD-L1 expression is the routine clinical biomarker for the selection of patients to receive immunotherapy in non-small cell lung cancer (NSCLC). However, the application and best timing of immunotherapy in the resectable setting is still under investigation. We aimed to study the effect of chemotherapy on PD-L1 expression and tumor infiltrating lymphocytes (TILs), which is to date still poorly understood. Our retrospective, single-centre neoadjuvant cohort comprised 96 consecutive patients with NSCLC resected 2000-2016 after neoadjuvant therapy, including paired diagnostic chemo-naïve specimens in 53 cases. A biologically matched surgical cohort of 114 primary resected cases was included. PD-L1 expression, CD8 + TILs density and tertiary lymphoid structures were assessed on whole slides and correlated with clinico-pathological characteristics and survival. Seven/53 and 12/53 cases had lower respectively higher PD-L1 expressions after neoadjuvant therapy. Most cases (n = 34) showed no changes in PD-L1 expression, the majority of these harboring PD-L1 < 1% in both samples (21/34 [61.8%]). Although CD8 + TILs density was significantly higher after chemotherapy (p = 0.031) in resections compared to diagnostic biopsies, this might be due to sampling and statistical bias. No difference in PD-L1 expression or CD8 + TILs density was detected when comparing the neoadjuvant and surgical cohort. In univariable analyses, higher CD8 + TILs density, higher numbers of tertiary lymphoid structures but not PD-L1 expression were significantly associated with longer survival. Increased PD-L1 expression after neoadjuvant chemotherapy was not significantly associated with shorter 5-year survival, but the number of cases was very low. In multivariable analysis, only pT category and age remained independent prognostic factors. In summary, PD-L1 expression was mostly unchanged after neoadjuvant chemotherapy compared to diagnostic biopsies. The sample size of cases with changed PD-L1 expression was too small to draw conclusions on any prognostic value.

Serum levels of VCAM-1 are associated with survival in patients treated with nivolumab for NSCLC

BACKGROUND

High circulating levels of cellular adhesion molecules (CAMs) in non-small cell lung cancer (NSCLC) have been supposed to act as a negative prognostic factor. Here, we explored the predictive role of pre-treatment levels of CAMs in previously treated patients receiving nivolumab for NSCLC.

MATERIALS AND METHODS

Seventy one patients with advanced NSCLC, treated with nivolumab at the dose of 3 mg/kg every 14 days, were enrolled. Maximum follow-up time was 3 years. Serum levels of Vascular Cell Adhesion Molecule-1 (VCAM-1) and Intracellular Adhesion Molecule-1 (ICAM-1) were measured at baseline and before each nivolumab administration. Endpoints of the study were a composite outcome of survival ≥2 years or absence of disease progression at the end of the follow-up, and the overall survival.

RESULTS

Composite outcome and overall survival were positively associated with VCAM-1 baseline levels and with the reduction of VCAM-1 during the treatment. After adjustment for potential confounders, the change in VCAM-1 serum levels during the treatment was an independent predictor of overall survival.

CONCLUSIONS

High baseline serum levels of VCAM-1 are associated with a longer survival in patients treated with nivolumab as second line treatment for NSCLC. Surviving patients experience also a significant reduction in CAMs expression during the treatment. Hence, CAMs might be promising prognostic factors in patients with NSCLC underoing immunotherapy.

Programmed death ligand 2 expression plays a limited role in adenocarcinomas of the gastroesophageal junction after preoperative chemotherapy

Background

The effects of cytotoxic chemotherapy on the expression of programmed death ligand 2 (PD-L2) are unknown and little is known about how the tumor microenvironment changes following neoadjuvant chemotherapy in locally advanced gastroesophageal adenocarcinomas (AEG). Recently, a number of studies reported that cytotoxic chemotherapy affects the expression levels of programmed cell death protein 1 (PD-1) and its ligand 1 (PD-L1). Regarding PD-L2, the second known ligand of PD‑1, no data on potential changes in expression patterns in patients with preoperatively treated AEG are available. The aim of this study was to investigate the impact of cytotoxic chemotherapy on PD-L2 expression in patients with resectable AEG.

Methods

Consecutive patients with locally advanced AEG treated with preoperative cytotoxic chemotherapy were included. PD-L2 expression by cancer cells (CCs) and tumor-infiltrating lymphocytes (TILs) was investigated in samples of paired diagnostic biopsies and resected tumor specimens by immunohistochemistry using two different anti-PD-L2 antibodies.

Results

Included were 40 patients with AEG and available paired tumor tissue samples. PD-L2 expression was observed in one diagnostic biopsy sample by CCs and in one diagnostic biopsy sample by TILs. There was no difference concerning the expression levels measured by the two antibodies.

Conclusion

In contrast to previously published studies reporting PD-L2 expression rates of up to 50% in AEGs, in our cohort, PD-L2 expression seems to play no significant role in AEG.

Exploration of a Novel Prognostic Risk Signature and Its Effect on the Immune Response in Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is a highly invasive and metastatic carcinoma with different molecular characteristics and clinical outcomes. In this work, we aimed to establish a novel gene signature that could predict the prognosis of NPC patients. A total of 13 significant genes between the recurrence/metastasis (RM) group and the no recurrence/metastasis (no-RM) group were identified by machine learning from RNA-Seq data including 60 NPC tumor biopsies. Based on these genes, a 4-mRNA signature (considering U2AF1L5, TMEM265, GLB1L and MLF1) was identified. Receiver operating characteristic (ROC) and Kaplan-Meier (K-M) analyses indicated that this signature had good prognostic value for NPC. The overall survival (OS) and progression-free survival (PFS) of the patients in the high-risk group were significantly shorter than those of the patients in the low-risk group (p = 0.00126 and p = 0.000059, respectively). The area under the ROC curve (AUC) values of the 4-mRNA signature were higher than those of T stage and N stage for OS (0.893 vs 0.619 and 0.582, respectively) and PFS (0.86 vs 0.538 and 0.622, respectively). Furthermore, the 4-mRNA signature was closely associated with cell proliferation and the immune response. The expression of GLB1L and TMEM265 was associated with the level of tumor-infiltrating immune cells (r > 0.4, p < 0.05). We have validated the model through measuring the expression levels of the 4-mRNA signature by qRT-PCR, in an independent cohort of NPC patients. Here, we report a novel gene signature that can serve as a new tool for predicting the prognosis of NPC patients.

Prospective observational study of nutritional/immunologic indices as predictive biomarkers for the response to anti-PD-1 drugs in non-small cell lung cancer (ICI-PREDICT study)

Immune checkpoint inhibitors (ICIs) targeting programmed cell death-1 (PD-1) and programmed cell death-ligand 1 (PD-L1) have markedly improved the prognosis of many patients with advanced non-small cell lung cancer (NSCLC). However, the relationship between the patient’s nutritional/immunologic status and the outcomes of ICI treatment remains unclear. In previous retrospective studies, we reported that the controlling nutritional status (CONUT) score, skeletal muscle area, and neutrophil-to-lymphocyte ratio were independent predictors of the response of NSCLC patients to anti-PD-1 drugs. The aim of this prospective multi-center study is to investigate the clinical impact of pre-treatment nutritional/immunologic indices and early post-treatment changes in the indices on treatment outcomes in advanced NSCLC. The main inclusion criteria are: (1) stage IV NSCLC, or stage III NSCLC not applicable for definitive chemoradiotherapy; (2) treatment with ICIs (monotherapy or combined with chemotherapy) as first-line therapy; and (3) available data on PD-L1 expression on tumor cells. A total of 300 patients will be enrolled prospectively. Enrollment will begin in 2020 and the final analyses will be completed by 2025.

Current Landscape of Non-Small Cell Lung Cancer: Epidemiology, Histological Classification, Targeted Therapies, and Immunotherapy

Non-small cell lung cancer (NSCLC) is a subtype of the most frequently diagnosed cancer in the world. Its epidemiology depends not only on tobacco exposition but also air quality. While the global trends in NSCLC incidence have started to decline, we can observe region-dependent differences related to the education and the economic level of the patients. Due to an increasing understanding of NSCLC biology, new diagnostic and therapeutic strategies have been developed, such as the reorganization of histopathological classification or tumor genotyping. Precision medicine is focused on the recognition of a genetic mutation in lung cancer cells called "driver mutation" to provide a variety of specific inhibitors of improperly functioning proteins. A rapidly growing group of approved drugs for targeted therapy in NSCLC currently allows the following mutated proteins to be treated: EGFR family (ERBB-1, ERBB-2), ALK, ROS1, MET, RET, NTRK, and RAF. Nevertheless, one of the most frequent NSCLC molecular sub-types remains without successful treatment: the K-Ras protein. In this review, we discuss the current NSCLC landscape treatment focusing on targeted therapy and immunotherapy, including first- and second-line monotherapies, immune checkpoint inhibitors with chemotherapy treatment, and approved predictive biomarkers.

PD-L1 Dependent Immunogenic Landscape in Hot Lung Adenocarcinomas Identified by Transcriptome Analysis

Simple Summary

Lung cancer, with non-small-cell lung cancer as its most common form, is the leading cause of cancer-related mortality and shows a poor prognosis. Despite recent advantages in the field of immunotherapy, there is still a great need for an improved understanding of PD-1/PD-L1 checkpoint blockade-responsive biology. Since immune cell infiltration is regarded as an important parameter in this field, we aimed to identify the immunogenic landscape in primary lung adenocarcinoma on the transcriptomic level in context with tumoral PD-L1 expression (positive vs. negative) and extent of immune infiltration (“hot” vs. “cold” phenotype). Our results reveal that genes that are related to the tumor microenvironment are differentially expressed based on tumoral PD-L1 expression indicating novel aspects of PD-L1 regulation, with potential biological relevance, as well as relevance for immunotherapy response stratification.

Abstract

Background: Lung cancer is the most frequent cause of cancer-related deaths worldwide. The clinical development of immune checkpoint blockade has dramatically changed the treatment paradigm for patients with lung cancer. Yet, an improved understanding of PD-1/PD-L1 checkpoint blockade-responsive biology is warranted. Methods: We aimed to identify the landscape of immune cell infiltration in primary lung adenocarcinoma (LUAD) in the context of tumoral PD-L1 expression and the extent of immune infiltration (“hot” vs. “cold” phenotype). The study comprises LUAD cases (n = 138) with “hot” (≥150 lymphocytes/HPF) and “cold” (<150 lymphocytes/HPF) tumor immune phenotype and positive (>50%) and negative (<1%) tumor PD-L1 expression, respectively. Tumor samples were immunohistochemically analyzed for expression of PD-L1, CD4, and CD8, and further investigated by transcriptome analysis. Results: Gene set enrichment analysis defined complement, IL-JAK-STAT signaling, KRAS signaling, inflammatory response, TNF-alpha signaling, interferon-gamma response, interferon-alpha response, and allograft rejection as significantly upregulated pathways in the PD-L1-positive hot subgroup. Additionally, we demonstrated that STAT1 is upregulated in the PD-L1-positive hot subgroup and KIT in the PD-L1-negative hot subgroup. Conclusion: The presented study illustrates novel aspects of PD-L1 regulation, with potential biological relevance, as well as relevance for immunotherapy response stratification.

UBE2V2 Positively Correlates With PD-L1 Expression and Confers Poor Patient Survival in Lung Adenocarcinoma

This research aims to explore the diagnostic and prognostic value of ubiquitin-conjugating enzyme E2 variant 2 (UBE2V2) in lung adenocarcinoma (LUAD). The expression of UBE2V2 in clinical specimens was evaluated by bioinformatics analyses and immunohistochemistry. Bioinformatics analyses relying on the The Cancer Genome Atlas (TCGA) database suggested the elevated UBE2V2 mRNA levels in LUAD in comparison to adjacent normal tissues. Gene set enrichment analyses and gene ontology term enrichment analyses further showed the involvement of UBE2V2 in the modulation of cell cycle and immune associated signaling. The correlation analyses in TCGA LUAD data set revealed the positive correlation between UBE2V2 and CCNE1, CCNE2, CCNA2, CCNB1, CCNB2, cyclin-dependent kinase (CDK)2, CDK4, and CDK1 at the mRNA level. Moreover, UBE2V2 mRNA levels were positively correlated with PD-L1 mRNA levels, the T classification, and poor survival of LUAD patients, and were negatively correlated with type II interferon response. Consistent with the results obtained from TCGA data mining, immunohistochemistry demonstrated that UBE2V2 protein levels were upregulated in LUAD in comparison to normal tissues and were positively associated with T classification. Intriguingly, a positive correlation between UBE2V2 protein levels and PD-L1 expression was also elucidated in clinical samples. Besides, UBE2V2 expression indicated a poor prognosis in LUAD patients. Our study found that UBE2V2 was identified as an independent prognostic indicator for LUAD and might serve as an alternative target for LUAD treatment.

Current challenges in targeting tumor desmoplasia to improve the efficacy of immunotherapy

Desmoplasia is crucial for the development, progression and treatment of immune-resistant malignancies. and treatment of immune-resistant malignancies. Targeting desmoplasia-related metabolic pathways appears to be an interesting approach to expand our stock of disposable anti-tumor agents.CXCL12/CXCR4 axis inhibition reduces fibrosis, alleviates immunosuppression and significantly enhances the efficacy of PD-1 immunotherapy. CD40L substitute therapy may increase the activity of T-cells, downregulate CD40+, prolong patients' survival and prevent cancer progression. Although FAPα antagonists used in preclinical models did not lead to permanent cure, an alleviation of immune-resistance, modification of desmoplasia and a decrease in angiogenesis were observed. Targeting DDR2 may enhance the effect of anti-PD-1 treatment in multiple neoplasm cell lines and has the ability to overcome the adaptation to BRAF-targeted therapy in melanoma. Reprogramming desmoplasia could potentially cooperate not only with present treatment, but also other potential therapeutic targets. We present the most promising metabolic pathways related to desmoplasia and discuss the emerging strategies to improve the efficacy of immunotherapy.

Prognostic value of Thyroid Transcription Factor-1 expression in lung adenocarcinoma in patients treated with anti PD-1/PD-L1

Anti-PD1/PD-L1-directed immune checkpoint inhibitors are game changers in advanced non-small-cell lung cancer, but biomarkers are lacking. The aim of our study was to find clinically relevant biomarkers of the efficacy of ICI in non-squamous NSCLC. We conducted a retrospective study of patients receiving ICI for advanced non squamous NSCLC in two cohorts. For a subset of patients, RNAseq data were generated on tumor biopsy taken before ICI. The primary end point was progression-free survival under ICI. Secondary end point was overall survival from ICI initiation. In the cohort, we studied 231 patients. Clinico-pathological characteristics included KRAS mutant status (n = 88), TTF1-positive expression (n = 136), LIPI (Lung Immune Prognostic Index) score of 0 (n = 116). In our cohort, lack of TTF1 expression, LIPI score >0, line of treatment >1, and liver metastases were associated with poorer PFS. TTF1 and PD-L1 status could be used to stratify survival and improve the AUC for prediction of prognosis in comparison with the PD-L1 gold standard. Using an external cohort of 154 patients, we confirmed the independent prognostic role of TTF1. TTF1 expression and PD-L1 can be used to stratify risk and predict PFS and OS in patients treated with ICI for NS-NSCLC.

Immunotherapy in Treating EGFR-Mutant Lung Cancer: Current Challenges and New Strategies

Lung cancer is the leading cause of cancer-related deaths worldwide. Immune checkpoint inhibitors, including monoclonal antibodies against programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1), have dramatically improved the survival and quality of life of a subset of non-small cell lung cancer (NSCLC) patients. Multiple predictive biomarkers have been proposed to select the patients who may benefit from the immune checkpoint inhibitors. EGFR-mutant NSCLC is the most prevalent molecular subtype in Asian lung cancer patients. However, patients with EGFR-mutant NSCLC show poor response to anti-PD-1/PD-L1 treatment. While small-molecule EGFR tyrosine kinase inhibitors (TKIs) are the preferred initial treatment for EGFR-mutant NSCLC, acquired drug resistance is severely limiting the long-term efficacy. However, there is currently no further effective treatment option for TKIs-refractory EGFR-mutant NSCLC patients. The reasons mediating the poor response of EGFR-mutated NSCLC patients to immunotherapy are not clear. Initial investigations revealed that EGFR-mutated NSCLC has lower PD-L1 expression and a low tumor mutational burden, thus leading to weak immunogenicity. Moreover, the use of PD-1/PD-L1 blockade prior to or concurrent with osimertinib has been reported to increase the risk of pulmonary toxicity. Furthermore, emerging evidence shows that PD-1/PD-L1 blockade in NSCLC patients can lead to hyperprogressive disease associated with dismal prognosis. However, it is difficult to predict the treatment toxicity. New biomarkers are urgently needed to predict response and toxicity associated with the use of PD-1/PD-L1 immunotherapy in EGFR-mutated NSCLC. Recently, promising data have emerged to suggest the potentiation of PD-1/PD-L1 blockade therapy by anti-angiogenic agents and a few other novel therapeutic agents. This article reviews the current investigations about the poor response of EGFR-mutated NSCLC to anti-PD-1/PD-L1 therapy, and discusses the new strategies that may be adopted in the future.

PD-L1 expression and its clinicopathologic and genomic correlation in the non-small cell lung carcinoma patients: An Indian perspective

BACKGROUND

Immunotherapy with checkpoint inhibitor programmed death-1 (PD-1) and programmed death-ligand 1 (PD-L1) antibodies targeting the cellular immune checkpoints is the present area of interest showing promising results in patients with advanced non-small cell lung cancer (NSCLC). As there is paucity of PD-L1 expression data from the Indian perspective, we studied the correlation of clinicopathologic profile and oncogenic driver mutations in these patients.

MATERIALS AND METHODS

Samples from 252 advanced NSCLCs patients were studied for PD-L1 expression through immunohistochemistry using rabbit anti-human PD-L1 monoclonal antibody (clone SP263) on Ventana BenchMark ULTRA autostainer. Simultaneously, genetic mutations were studied by next generation sequencing (for EGFR, ALK, ROS, MET, and BRAF). PD-L1 expression was analyzed for association with clinicopathologic features and various mutations.

RESULTS

PD-L1 positivity was seen in 134 patients (53.2 %). It was twice more prevalent in males than females. No significant correlation was observed between PD-L1 expression with age, gender, site of testing (primary vs. metastatic tumors), smoking status, tumor laterality, stage, or histologic type; however, there was significant difference among solid and acinar types of adenocarcinoma combined together vs. other adenocarcinoma subtypes (p = 0.013), and well and moderately differentiated vs. poorly differentiated tumors (p = 0.022). When types/extent of PD-L1 positivity (≥25 %) were compared with demographics, clinical, and pathologic variables, significant differences were observed across the tumor grades (high-grade vs. low-grade) (p = 0.009) and stages (p = 0.039). The PD-L1 expression failed to demonstrate any statistical significance with oncogenic drivers. High PD-L1 expression (TPS ≥ 50) was observed in 27.6 % patients, and it was more prevalent in female patients (32.4 %), aged ≥60 years (33.8 %), smokers (27.3 %), poorly differentiated (36.8 %) and stage IV tumors (28.2 %). Exon 19 deletion was more prevalent in PD-L1 negative tumors whereas exon 21 substitution (L858R) was seen more in PD-L1 positive tumors.

CONCLUSIONS

This is the largest Indian study demonstrating PD-L1 expression in NSCLC patients comparing with clinicopathologic and genomic parameters. PD-L1 expression was significantly associated with high-grade, solid, and acinar types of adenocarcinoma and advanced tumors. High PD-L1 expression was more prevalent in female patients, aged ≥60 years, smokers, and poorly differentiated and stage IV tumors (28.2 %). Exon 19 deletion was more in PD-L1 negative tumors whereas exon 21 substitution (L858R) was more in PD-L1 positive tumors. PD-L1 is a potential predictive marker stratifying patients who benefit from PD-1 pathway-targeted therapy.

Spontaneous regression of incidentally diagnosed bronchial squamous cell lung carcinoma after severe bronchitis: A case report

Spontaneous regression of lung cancer is exceptionally rare. But there have been several intriguing cases reported in early and even advanced stages of lung cancer. Although the exact mechanism remains to be elucidated, the inflammation and immunologic response have been suggested as one of the means of spontaneous regression. Chronic inflammation is generally known to induce and aggravate tumorigenesis, but the relationship between cancer and inflammation highly depends on the contexts. Here, we present a case of a 60-year-old male ex-smoker who complained of recurrent hemoptysis, cough, and purulent sputum. The initial chest CT scan revealed diffuse bronchial thickening and an endobronchial mass-like lesion in the left lingular segment. The bronchoscopic and pathological findings also suggested a diagnosis of squamous cell carcinoma with severe mucosal inflammation. He was treated with antibiotics for the bronchitis during the first 1 week and his symptoms markedly improved. After 3 weeks, he underwent a follow-up examination. Chest computed tomography and bronchoscopy revealed the significant improvement of the bronchial narrowing and mucosal edema. Biopsy was performed several times around the lesion where the tissue was initially taken. However, the pathological results showed only chronic inflammation of bronchi, not cancer cells. Fortunately, there was no recurrence of lung cancer in follow-up chest computed tomography or bronchoscopy for almost 5 years. In this case, the incidentally diagnosed bronchial squamous cell carcinoma disappeared after severe inflammatory reaction of the bronchial wall. The clinician should remind the risk of early lung cancer accompanied with bronchitis in high-risk patients of lung cancer and also be aware that although it is very rare, the lesions could spontaneously regress.

Expression and analysis of PD-L1 in peripheral blood circulating tumor cells of lung cancer

Aim: PD-L1 is an important immune intervention target for lung cancer treatment; however, its clinical significance and biological function in circulating tumor cells (CTCs) of lung cancer need to be explored in depth. Materials & methods: In this study, the CanPatrol method was used to detect three types of CTCs and PD-L1 in 271 lung cancer patients from December 2015 to October 2019. Results: Smoking index, pathological diagnosis and clinical stage are independent influencing factors of PD-L1 expression. The methods that affect the count of CTCs are first-line chemotherapy and targeted therapy; however, there is no difference in the expression of PD-L1 with different treatments. Conclusions: The detection of CTCs and PD-L1 in peripheral blood is helpful for the diagnosis of lung cancer patients.

The lung immuno-oncology prognostic score (LIPS-3): a prognostic classification of patients receiving first-line pembrolizumab for PD-L1 ≥ 50% advanced non-small-cell lung cancer

Background

To stratify the prognosis of patients with programmed cell death-ligand 1 (PD-L1) ≥ 50% advanced non-small-cell lung cancer (aNSCLC) treated with first-line immunotherapy.

Methods

Baseline clinical prognostic factors, the neutrophil-to-lymphocyte ratio (NLR), PD-L1 tumour cell expression level, lactate dehydrogenase (LDH) and their combination were investigated by a retrospective analysis of 784 patients divided between statistically powered training (n = 201) and validation (n = 583) cohorts. Cut-offs were explored by receiver operating characteristic (ROC) curves and a risk model built with validated independent factors by multivariate analysis.

Results

NLR < 4 was a significant prognostic factor in both cohorts (P < 0.001). It represented 53% of patients in the validation cohort, with 1-year overall survival (OS) of 76.6% versus 44.8% with NLR > 4, in the validation series. The addition of PD-L1 ≥ 80% (21% of patients) or LDH < 252 U/l (25%) to NLR < 4 did not result in better 1-year OS (of 72.6% and 74.1%, respectively, in the validation cohort). Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 2 [P < 0.001, hazard ratio (HR) 2.04], pretreatment steroids (P < 0.001, HR 1.67) and NLR < 4 (P < 0.001, HR 2.29) resulted in independent prognostic factors. A risk model with these three factors, namely, the lung immuno-oncology prognostic score (LIPS)-3, accurately stratified three OS risk-validated categories of patients: favourable (0 risk factors, 40%, 1-year OS of 78.2% in the whole series), intermediate (1 or 2 risk factors, 54%, 1-year OS 53.8%) and poor (>2 risk factors, 5%, 1-year OS 10.7%) prognosis.

Conclusions

We advocate the use of LIPS-3 as an easy-to-assess and inexpensive adjuvant prognostic tool for patients with PD-L1 ≥ 50% aNSCLC.

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Immunotherapy/chemoimmunotherapy combinations are currently not superior to immunotherapy alone for high PD-L1 aNSCLC.

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NLR with a cut-off of 4 was validated as an independent prognostic factor for immunotherapy in high PD-L1 aNSCLC.

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The addition of either PD-L1 ≥ 80% or LDH < 252 U/l to NLR < 4 did not result in better prognostic stratification.

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The LIPS-3 is a validated 3-class prognostic classification based on the NLR, ECOG PS and pretreatment steroids.

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The LIPS-3 is a routinely assessable adjuvant prognostic tool for high PD-L1 aNSCLC patients.

Bioinformatics-Based Identification of HDAC Inhibitors as Potential Drugs to Target EGFR Wild-Type Non-Small-Cell Lung Cancer

Patients with EGFR-mutant non-small-cell lung cancer (NSCLC) greatly benefit from EGFR-tyrosine kinase inhibitors (EGFR-TKIs) while the prognosis of patients who lack EGFR-sensitive mutations (EGFR wild type, EGFR-WT) remains poor due to a lack of effective therapeutic strategies. There is an urgent need to explore the key genes that affect the prognosis and develop potentially effective drugs in EGFR-WT NSCLC patients. In this study, we clustered functional modules related to the survival traits of EGFR-WT patients using weighted gene co-expression network analysis (WGCNA). We used these data to establish a two-gene prognostic signature based on the expression of CYP11B1 and DNALI1 by combining the least absolute shrinkage and selection operator (LASSO) algorithms and Cox proportional hazards regression analysis. Following the calculation of risk score (RS) based on the two-gene signature, patients with high RSs showed a worse prognosis. We further explored targeted drugs that could be effective in patients with a high RS by the connectivity map (CMap). Surprisingly, multiple HDAC inhibitors (HDACis) such as trichostatin A (TSA) and vorinostat (SAHA) that may have efficacy were identified. Also, we proved that HDACis could inhibit the proliferation and metastasis of NSCLC cells in vitro. Taken together, our study identified prognostic biomarkers for patients with EGFR-WT NSCLC and confirmed a novel potential role for HDACis in the clinical management of EGFR-WT patients.

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

INTRODUCTION

PD1/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 RESULTS

A 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).

CONCLUSIONS

Overexpression 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.

Prognostic and clinicopathological value of PD-L2 in lung cancer: A meta-analysis

OBJECTIVE

The prognostic role of programmed death ligand-2 (PD-L2) expression in lung cancer has been widely studied, however, the results are controversial. Accordingly, we investigated the prognostic and clinicopathological value of PD-L2 in patients with lung cancer in this meta-analysis.

METHODS

Relevant studies were systematically searched in the PubMed, Web of Science, EMBASE, ClinicalTrials.gov., Scopus, and Cochrane Library until July 10, 2020. The hazard ratio (HR), odds ratio (OR), and their corresponding 95% confidence intervals (CIs) were calculated.

RESULTS

Thirteen studies with 3107 participants were included. High PD-L2 expression was associated with poor overall survival (OS) (HR 1.248, 95% CI: 1.071-1.455, p = 0.004) and worse disease-free survival (DFS)/progression-free survival (PFS)/relapse-free survival (RFS) (HR 1.224, 95% CI: 1.058-1.417, p = 0.007) in lung cancer. Furthermore, unfavorable OS was found in lung adenocarcinoma (HR 1.349, 95% CI: 1.051-1.731, p = 0.019), but not in other pathological types (HR 1.192, 95% CI: 0.982-1.447 p = 0.076) with higher PD-L2 expression in our subgroup analysis. Concerning the clinicopathological characteristics, high PD-L2 expression was associated with smoking (OR 0.725, 95% CI: 0.591-0.890, p = 0.002) and PD-L1 (OR 1.607, 95% CI:1.115-2.314, p = 0.011) and vascular invasion (OR 1.500, 95% CI: 1.022-2.203, p = 0.039).

CONCLUSION

PD-L2 overexpression might predict a poor prognosis in lung cancer patients after surgery. PD-L2 expression might be a potential biomarker for PD-1/PD-L1-targeted immunotherapy in lung cancer, which should be investigated in future studies.

Clinical significance of preoperative inflammatory markers in non-small cell lung cancer patients: A multicenter retrospective study

Inflammatory biomarkers have been associated with clinical outcomes in non-small cell lung cancer (NSCLC). However, the best prognostic marker(s) has not been identified, and the association between inflammatory markers and clinical characteristics is poorly understood. We selected 1,237 patients with resected NSCLC from Kyushu University (2003–2015) and Kyushu Cancer Center (2009–2015) in Japan. Pearson product-moment correlation coefficient among inflammatory markers and area under curve (AUC) of receiver operating characteristic (ROC) curve analyses for overall survival (OS) were calculated. We analyzed the associations between inflammatory markers and clinical factors using Student’s t-test. Univariate and multivariate analyses with Cox proportional hazards regression analyses were performed to evaluate the relationship between survival and clinical factors. The cut-off values for neutrophil-lymphocyte ratio (NLR), lymphocyte-monocyte ratio (LMR), platelet-lymphocyte ratio, and derived NLR (dNLR) were determined by ROC curve analyses for OS. We found a strong positive correlation between NLR and dNLR (r = 0.9629). The AUC of LMR was the highest amongst the measured metrics, and the AUC of NLR was higher than dNLR. Levels of some inflammatory markers were associated with sex, smoking, squamous cell carcinoma, and pathological stage. LMR ≥ 5.11 and lactate dehydrogenase (LDH) concentration ≥ 222 (U/L) were independent predictors of both disease-free survival (DFS) and OS (LMR; P = 0.0009 and 0.0008, LDH; P = 0.0195 and 0.0187, respectively). Certain inflammatory markers, potentially linked to smoking, were associated with an advanced pathological stage in NSCLC. LMR and LDH were independent predictors of both DFS and OS.

The potential of 18F-FDG PET/CT in predicting PDL1 expression status in pulmonary lesions of untreated stage IIIB-IV non-small-cell lung cancer

OBJECTIVES

To investigate the potential of 2-deoxy-2(¹⁸F)fluoro-d-glucose (¹⁸F-FDG) combined positron emission tomography and computed tomography (PET/CT) in predicting programmed cell death ligand-1 (PDL1) expression status in pulmonary lesions of advanced non-small-cell lung cancer (NSCLC).

MATERIALS AND METHODS

This retrospective study includes 133 untreated stage IIIB-IV NSCLC patients who underwent pulmonary lesion biopsy for PDL1 immunochemistry 1-4 weeks after ¹⁸F-FDG PET/CT scanning, randomly assigned to cohorts for modelling and validation of PDL1 expression predictors. Mean and maximum standard uptake values (pSUVmean and pSUVmax), metabolic tumour volume (pMTV), and total lesion glycolysis (pTLG) of primary lesions were determined. PDL1 expression in pulmonary lesions (pPDL1) was determined using tumour proportion score (TPS), and pPDL1 TPS < 1%, 1-49 %, and ≥ 50 % were considered as pPDL1-negative, pPDL1-moderate, and pPDL1-strong, respectively.

RESULTS

pSUVmean and pSUVmax values were increased with the increase of pPDL1 levels, whereas pMTV and pTLG values were not associated with pPDL1 levels. In the modelling cohort, we found that pSUVmax rather than pSUVmean was an independent predictor for pPDL1-negative, pPDL1-moderate, and pPDL1-strong, whereas pSUVmax < 14.4, 14.4-17.5, and > 17.5 were suggested as predictors for pPDL1-negative, pPDL1-moderate, and pPDL1-strong, respectively (odds ratio: 4.82, 3.92, and 4.45, respectively; P = 0.002, 0.021, and 0.020, respectively). In the validation cohort, pSUVmax < 14.4, 14.4-17.5, and > 17.5 showed significantly high probabilities of being pPDL1-negative, pPDL1-moderate, and pPDL1-strong, respectively (P = 0.006). The accuracies of pSUVmax < 14.4, 14.4-17.5, and > 17.5 predicting pPDL1-negative, pPDL1-moderate, and pPDL1-strong, respectively, in validation cohort, were 66.7 %, 75.8 %, and 84.8 %, respectively.

CONCLUSION

pSUVmax on ¹⁸F-FDG PET/CT is a potential biomarker for pPDL1 TPS < 1%, 1-49 %, and ≥ 50 % in untreated stage IIIB-IV NSCLC, and therefore may be helpful for determining immunotherapeutic strategy for advanced NSCLC.

Re-biopsy after first line treatment in advanced NSCLC can reveal changes in PD-L1 expression

OBJECTIVES

Re-biopsy in progressive advanced Non-Small-Cell Lung Cancer (NSCLC) after first line treatment may reveal information about evolving tumor biology during treatment. Our study aims to investigate the feasibility, risk of complications, and clinical relevance of performing re-biopsy systematically.

MATERIALS AND METHODS

NSCLC patients with advanced, non-targetable disease, receiving first line systemic treatment, were included in a prospective single-centre study (NCT03512847). A diagnostic biopsy was performed at baseline and repeated at time of progression, preferentially from the progressive lesions as determined by CT or PET/CT. The primary endpoint was feasibility, including complication rate to re-biopsy. Secondary endpoints were clinical relevance, defined as a potential of changing treatment or follow-up, due to new histological evidence, specifically a change in PD-L1 Tumor Proportion Score (TPS).

RESULTS

Fifty-one patients with progressive advanced NSCLC had re-biopsy performed. Median time from patients' acceptance to biopsy was seven days (range: 0-31). Complication rate was 6% (n = 3) represented by pneumothorax, hydro-pneumothorax and pneumonia, respectively. No severe or chronic complications occurred. Sufficient material for PD-L1 analyses was obtained in 46 of 51 patients: the remaining five cases had insufficient tissue for analyses, no malignant cells/only suspected malignant cells, questioning whether progression was real. PD-L1 TPS change was observed in 33% of patients (n = 15) and 17% (n = 8) had potentially clinically relevant changes. A significantly higher chance of PD-L1 TPS change was observed in chemotherapy-treated patients.

CONCLUSION

Our study showed that re-biopsy is feasible, with low risk of complications, and can be clinically relevant in patients with suspected progression in advanced NSCLC.

Tumor mutation burden predicts response and survival to immune checkpoint inhibitors: a meta-analysis

Background

Cancer is one of the world’s top three causes of death now. Immune checkpoint inhibitors (ICIs) show encouraging ability to treat some malignancies due to its long-term efficacy and low side effects. However, the predictive biomarker of the immunotherapy efficacy has been inconclusive. Thus, exploring new biomarkers is important.

Methods

A meta-analysis was conducted to evaluate whether tumor mutation burden (TMB) could be a predictive biomarker of the efficacy of ICIs. Using the PubMed and Cochrane Library databases, we searched for articles about TMB and the prognosis of patients with multiple malignancies conducted from 1984 to May 22, 2020. We identified the relationship between TMB and the clinical efficacy of ICIs by using Stata 12.1 software.

Results

Eighteen articles with a total of 4,535 patients were included in this meta-analysis. Results showed that high-TMB patients had better progression-free survival (PFS) than low-TMB patients with cancer treated with ICIs (HR =0.45; 95% CI: 0.36–0.56, P=0.002). Moreover, high-TMB patients had longer overall survival (OS) than low-TMB patients. However, the heterogeneity was extremely high, so the result regarding OS was meaningless (HR =0.56; 95% CI: 0.44–0.70, P=0.000, I-squares: 72.6%).

Conclusions

Our study indicates that high TMB is associated with better PFS. Thus, TMB can be considered as a predictive marker of PFS of patients treated with ICIs in the future.

Clinical Impact of the Epithelial-Mesenchymal Transition in Lung Cancer as a Biomarker Assisting in Therapeutic Decisions

Lung cancer is one of the most common solid cancers and represents the leading cause of cancer death worldwide. Over the last decade, research on the epithelial-mesenchymal transition (EMT) in lung cancer has gained increasing attention. Here, we review clinical and histological features of non-small-cell lung cancer associated with EMT. We then aimed to establish potential clinical implications of EMT in current therapeutic options, including surgery, radiation, targeted therapy against oncogenic drivers, and immunotherapy.

Lobectomy versus sublobar resection in patients with non-small cell lung cancer: a systematic review

Surgery is the gold standard treatment of lung cancer. The minimally invasive technique does not only concern access to the chest but also the limits of parenchymal resection. The study debates on the safety and oncological adequacy of sublobar resections in bronchogenic carcinoma patients. A systematic analysis of the data in the literature was carried out, comparing the outcomes of patients with resectable non-small lung cancer (NSCLC) who underwent lobectomy or sublobar resection. These last interventions include both segmentectomies and wedge resections taking into consideration the following parameters: complications, relapse rate and overall survival. The complication rate is higher in patients underwent lobectomy compared to sublobar resection, especially in presence of high comorbidity index or octogenarian patients (overall values respectively between 0 and 48% and 0 and 46.6%). Contrarily, the relapse rate (6.2% to 32% vs. 3.6% to 53.4%) and overall survival (50.2% to 93.8% vs. 38.6% to 100%) are more favorable in patients undergoing lobectomy. Sublobar resections are particularly indicated in elderly patients and in patients with high comorbidity index or reduced respiratory functional reserve. However, pulmonary lobectomy still remains the safest and oncologically correct method in patients with good performance status or higher risk of recurrence.

Expression of PD-L1, PD-L2, and IDO1 on tumor cells and density of CD8-positive tumor-infiltrating lymphocytes in early-stage lung adenocarcinoma according to histological subtype

PURPOSE

This study examined the expression of programmed cell death-ligand 1 (PD-L1), programmed cell death-ligand 2 (PD-L2), and indoleamine 2,3-dioxygenase-1 (IDO1) in tumor cells and cluster of differentiation 8 (CD8)-positive tumor-infiltrating lymphocytes (TILs) in early-stage lung adenocarcinoma according to histological subtypes.

METHODS

We evaluated PD-L1, PD-L2, and IDO1 expression in tumor cells and CD8-positive TILs in surgically resected specimens from 196 stage 0 or I lung adenocarcinoma patients by immunohistochemical staining. We also examined the relationships between the expression of PD-L1, PD-L2, and IDO1 in tumor cells and the density of CD8-positive TILs and clinical factors. Patients were divided into three groups: A, adenocarcinoma in situ and minimally invasive adenocarcinoma (N = 32); B, lepidic predominant invasive adenocarcinoma (IAD; LPA; N = 66); and C, IAD except for LPA (N = 98).

RESULTS

PD-L1 was expressed only in Group C, but not in Groups A or B. The positive ratio of PD-L2 was significantly higher in Group C (63.3%), and that of IDO1 was also significantly higher in Group C (65.3%). The density of CD8-positive TILs was significantly higher in Group C (45 ± 2.4). There was no significant difference between the positive ratios of PD-L2 and IDO1 and the density of CD8-positive TILs in Group A (50.0%, 21.9%, and 36 ± 4.1, respectively) or Group B (60.6%, 25.8%, and 44 ± 3.0, respectively).

CONCLUSIONS

No cases in Groups A and B expressed PD-L1. The expression of immune-related factors, especially PD-L1 and IDO1, was significantly associated with Group C. This is the first report of the detailed examination of PD-L1, PD-L2, IDO1, and CD8 expression in lung adenocarcinoma subtypes with lepidic predominant components. Our results could help identify patients who would benefit from perioperative immunotherapy.

Surgically Resected Second Primary Lung Adenocarcinoma After Pembrolizumab Administration

Non-small cell lung cancer (NSCLC) patients are sometimes referred for thoracic surgical consultation to address the possibility of resecting second primary lung cancer. We report a case of pulmonary resection for second primary lung adenocarcinoma after 3 cycles of pembrolizumab under circumstances in which the primary metastatic lung adenocarcinoma was controlled. The tumor statuses, including programmed death-ligand 1, epidermal growth factor receptor, and CD8+ tumor-infiltrating lymphocytes, were different between the surgically resected specimen and the previously biopsied sample. Surgery should be considered for second primary NSCLC in cases in which the primary NSCLC are well controlled with immune checkpoint inhibitors.

Association between immune-related adverse events and long-term survival outcomes in patients treated with immune checkpoint inhibitors

BACKGROUND

The impact of immune-related adverse events (irAE) on survival outcomes after single-agent immune checkpoint inhibitors (ICIs) remains unclear. We aimed to evaluate the association between irAEs and ICI efficacy in various malignancies.

METHODS

All patients treated with a single-agent ICI for any advanced cancer were included in this retrospective multicentric series. The primary objective was to assess the impact of all type grade ≥II irAEs on progression-free survival (PFS) and overall survival (OS). IrAEs were first considered as a fixed covariate and included in Cox-regression models. In addition, as irAEs are time-related events and can occur at any point during follow-up, we analysed the occurrence of irAEs as a time-varying covariate.

RESULTS

In this cohort of 410 patients, the majority of patients (70%) were treated for non-small cell lung cancer. The ICI was an anti-PD(L)1 for 356 patients (82%) and an anti-CTLA4 for 79 patients (18%). In total 126 (29%) of the patients presented at least one grade ≥II irAEs. The first occurrence of a grade ≥II irAE had a positive impact on PFS and OS when considered as a fixed or as a time-varying covariate (hazard ratio [HR] for PFS = 0.63, 95% confidence interval [CI] 0.50-0.81; P = 0.00022; HR for OS = 0.57, 95% CI 0.43-0.74, P < 0.0001). This overall finding was confirmed in patients treated with an anti-PD(L)1 and among patients with lung cancer.

CONCLUSION

In this pooled multi-institutional cohort, the incidence of irAEs was associated with better long-term survival across different malignancies treated with ICI monotherapy.

Cutaneous Squamous Cell Carcinoma: From Biology to Therapy

Cutaneous squamous cell carcinoma (CSCC) is the second most frequent cancer in humans and its incidence continues to rise. Although CSCC usually display a benign clinical behavior, it can be both locally invasive and metastatic. The signaling pathways involved in CSCC development have given rise to targetable molecules in recent decades. In addition, the high mutational burden and increased risk of CSCC in patients under immunosuppression were part of the rationale for developing the immunotherapy for CSCC that has changed the therapeutic landscape. This review focuses on the molecular basis of CSCC and the current biology-based approaches of targeted therapies and immune checkpoint inhibitors. Another purpose of this review is to explore the landscape of drugs that may induce or contribute to the development of CSCC. Beginning with the pathogenetic basis of these drug-induced CSCCs, we move on to consider potential therapeutic opportunities for overcoming this adverse effect.

Biomarkers for Response to Immune Checkpoint Blockade

Immune checkpoint blockade (ICB) has significant clinical activity in diverse cancer classes and can induce durable remissions in even refractory advanced disease. However, only a minority of cancer patients treated with ICB have long-term benefits, and ICB treatment is associated with significant, potentially life-threatening, autoimmune side effects. There is a great need to develop biomarkers of response to guide patient selection to maximize the chance of benefit and prevent unnecessary toxicity, and current biomarkers do not have optimal positive or negative predictive value. A variety of potential biomarkers are currently being developed, including those based on assessment of checkpoint protein expression, evaluation of tumor-intrinsic features including mutation burden and viral infection, evaluation of features of the tumor immune microenvironment including nature of immune cell infiltration, and features of the host such as composition of the gut microbiome. Better understanding of the underlying fundamental mechanisms of immune response and resistance to ICB, along with the use of complementary assays that interrogate distinct features of the tumor, the tumor microenvironment, and host immune system, will allow more precise use of these therapies to optimize patient outcomes.

The Clinical Significance of Soluble Programmed Cell Death-Ligand 1 (sPD-L1) in Patients With Gliomas

Background: Soluble PD-L1 (sPD-L1) in the circulation has been documented to activate global immunosuppression and is considered a predictor of negative clinical outcomes in several malignances. However, the clinical significance of sPD-L1 in the peripheral blood and cerebrospinal fluid (CSF) of patients with glioma remains unclear.

Objective: The aim of this study was to detect the correlations of sPD-L1 with clinical features in brain tumors and assess the diagnostic value of this protein in gliomas.

Methods: Serum samples were obtained from 73 patients with glioma, 20 patients with meningioma, and 49 healthy controls (HCs) in this study. In total, 31 CSF samples were collected from the matched glioma patients, and seven samples were collected from the matched meningioma patients. The expression of serum sPD-L1 in the glioma cohort was followed for 20 days after surgery to examine the kinetics in the circulation. Inflammatory markers were evaluated based on preoperative blood parameters. The sPD-L1 levels in the serum and CSF were determined by enzyme-linked immunosorbent assay (ELISA). The logistic regression model was used to assess the independent associations of sPD-L1 with gliomas, including high-grade gliomas.

Results: Serum and CSF levels of sPD-L1 were significantly elevated in patients with gliomas compared to those with meningiomas and HCs. Additionally, increased levels of sPD-L1 were observed in relatively advanced tumors. sPD-L1 overexpression in the CSF appears to be more representative of aggressive tumor features than overexpression in the serum. For glioma diagnosis, both serum and CSF sPD-L1 showed significant value in the diagnosis and stratification of glioma, and the best diagnostic performance was obtained with serum sPD-L1 rather than blood-based inflammatory markers. In addition, a descending trend in the level of serum sPD-L1 was observed in postoperative patients.

Conclusion: In gliomas, elevated circulating and CSF sPD-L1 levels are associated with aggressive biological activities. The results of the current study suggest that sPD-L1 is a promising biomarker for gliomas that can be used in clinical practice.

Soluble programmed death-1 (sPD-1) and programmed death ligand 1 (sPD-L1) as potential biomarkers for the diagnosis and prognosis of glioma patients

Background

This study aimed at investigating the feasibility of testing for soluble programmed death-1 (sPD-1) and soluble programmed death ligand 1 (sPD-L1) in serum samples of glioma patients and to evaluate the diagnostic and prognostic value of these two soluble molecules.

Methods

Serum samples collected from 70 glioma patients before surgery were designated as the pre-operative (Pre) group, samples obtained from 90 post-surgery glioblastoma patients were designated as the Post group, and samples from 20 healthy volunteers were used as controls. Peripheral blood sPD-1 and sPD-L1 levels were detected by using ELISA kits and compared among the groups. The associations of these soluble molecule levels with clinicopathological variables and tumour progression were investigated.

Results

Among the three groups, the Pre group had the highest sPD-1 levels, whereas the median sPD-L1 level was significantly lower in the Post group than in the other two groups. The area under the curve (AUC) of sPD-1 (0.762) for diagnosis was similar to that of sPD-L1 (0.718). Higher serum levels of sPD-1 and sPD-L1 were present in samples of patients with more advanced brain tumours. Kaplan-Meier analysis showed that higher serum levels of sPD-1 (>11.14 pg/mL) and sPD-L1 (>63.03 pg/mL) might predict shorter progression-free survival times of glioma patients.

Conclusions

This study showed that sPD-1 and sPD-L1 might be promising predictive biomarkers for the diagnosis and prognosis of glioma patients.

Ectonucleotidase CD39 and Checkpoint Signalling Receptor Programmed Death 1 are Highly Elevated in Intratumoral Immune Cells in Non-small-cell Lung Cancer

Lung cancer is the leading cause of cancer death in both sexes worldwide and has a predicted 5-year survival rate of <20%. Immunotherapy targeting immune checkpoints such as the programmed death 1 (PD-1) signaling pathway has led to a shift of paradigm in the treatment of advanced non–small-cell lung cancer (NSCLC) but remains without effect in ∼80% of patients. Accumulating evidence suggests that several immunosuppressive mechanisms may work together in NSCLC. The contribution and cooperation between different immunosuppressive mechanisms in NSCLC remain unknown. Recently, the CD39-adenosine pathway has gained increasing attention as a crucial immunosuppressive mechanism and possible target for immunotherapy. Immune cells were extracted from lung and tumor tissue after lung resection in 12 patients by combined enzymatic and mechanical tissue disaggregation. A multiparameter flow cytometry panel was established to investigate the expression and coexpression of CD39 and PD-1 on key lymphocyte subtypes. Frequencies of CD39⁺, PD-1⁺, and CD39⁺/PD-1⁺cells were higher among both CD4⁺ and CD8⁺ T cells isolated from NSCLC tumor tissue than in T cells from normal lung tissue. Similarly, the frequency of FoxP3⁺ CD4⁺ T cells (Tregs) was highly significantly elevated in tumor tissue compared to adjacent lung tissue. The consistent upregulation of CD39 on immune cells in tumor microenvironment indicates that the CD39 signaling pathway may, in addition to the PD-1 pathway, represent another important mechanism for tumor-induced immunosuppression in NSCLC. In addition, the present study indicates that a comprehensive immune response profiling with flow cytometry may be both feasible and clinically relevant.

Significant differences in T cell receptor repertoires in lung adenocarcinomas with and without epidermal growth factor receptor mutations

Recent clinical trials of non‐small cell lung cancer with immune checkpoint inhibitors revealed that patients with epidermal growth factor receptor (EGFR) mutations had more unfavorable outcomes compared with those with wild‐type EGFR. However, the underlying mechanism for the link between EGFR mutations and immune resistance remains unclear. We performed T cell receptor (TCR) repertoire analysis of resected lung adenocarcinoma tissues with and without EGFR mutations to investigate the characteristics of TCR repertoires. We collected a total of 39 paired (normal and tumor) lung tissue samples (20 had EGFR mutations) and conducted TCR repertoire analysis as well as whole‐exome sequencing (WES) and transcriptome analysis. The TCR diversity index in EGFR‐mutant tumors was significantly higher than that in EGFR‐wild‐type tumors (median [range] 552 [162‐1,135] vs 230 [30‐764]; P < .01), suggesting higher T cell clonal expansion in EGFR‐wild‐type tumors than in EGFR‐mutant tumors. In WES, EGFR‐mutant tumors showed lower numbers of non‐synonymous mutations and predicted neoantigens than EGFR‐wild‐type tumors (P < .01, P = .03, respectively). The number of non‐synonymous mutations revealed a positive correlation with the sum of frequencies of the TCRβ clonotypes of 1% or higher in tumors (r = .52, P = .04). The present study demonstrates significant differences in TCR repertoires and the number of predicted neoantigens between EGFR‐mutant and wild‐type lung tumors. Our findings provide important information for understanding the molecular mechanism behind EGFR‐mutant patients showing unfavorable responses to immune checkpoint inhibitors.

Deciphering Microenvironment of NSCLC based on CD8+ TIL Density and PD-1/PD-L1 Expression

Purpose: To determine whether distinct tissue immune microenvironments differentially impact on clinical outcome in non-small cell lung cancer (NSCLC), an extended analysis of PD-1/PD-L1 and Tumor Infiltrating Lymphocytes (TILs) was performed.

Materials and Methods: 1016 NSCLC mRNA-sequence samples from The Genome Data Analysis Center (TCGA) and 275 NSCLC mRNA-microarray samples from Gene Expression Omnibus (GEO) were included as testing cohort and validation cohort respectively. Enrichment scores of CD8+ T cells' metagene were used for quantifying its infiltrating density. Based on the median values of CD8+ T cell density and PD-1/PD-L1 mRNA expression, the samples were classified into four Tumor Immune Microenvironment types (TIMTs). Overall survival, as well as clinicopathological features, mutational profiles, mismatch repair score etc. were compared across the four types.

Results: Neither PD-1 expression nor PD-L1 expression was associated with outcome in the overall NSCLC. Classification of TIMT based on PD-1/PD-L1 and CD8+ TIL could efficiently classify patients of different survival in ADC but not SCC, with the best overall survival achieved in TIMT3 (high CD8+ TIL and low PD-1/PD-L1), whereas TIMT2 (low CD8+ TIL and high PD-1/PD-L1) manifested the worst outcome. TIMT classification based on PD-1/ CD8+ TIL could better stratify patient of different prognosis than PD-L1/ CD8+ TIL based classification. EGFR wide type and IFNγ overexpression were associated with TIMT4 (high PD-1/PD-L1 and high CD8+ TIL), whereas tumor mutational burden (TMB) manifested no significant difference across four TIMTs.

Conclusion: The classification of tumors into four microenvironment subtypes based on PD-1/PD-L1 status and CD8+ TIL is an appropriate approach to stratify patients of different clinical outcome and better guide the practical use of immunotherapy.

A Positive Correlation Between the EZH2 and PD-L1 Expression in Resected Lung Adenocarcinomas

BACKGROUND

Enhancer of zeste homolog 2 (EZH2) is reported to be involved in lung cancer pathogenesis via the epigenetic regulation of various genes. Recently, EZH2 was shown to control mechanisms of adaptive resistance to immunotherapy in melanoma; however, the association between EZH2 and programmed death-ligand 1 (PD-L1), which reflects the tumor microenvironment, remains poorly understood.

METHODS

A total of 428 patients with resected lung adenocarcinoma were analyzed for their EZH2 and PD-L1 expression by immunohistochemistry and evaluated to determine the association between the EZH2 and PD-L1 expression.

RESULTS

Among 428 patients, the EZH2 expression was identified in 219 (51.2%) patients, while the PD-L1 expression was observed in 88 (20.6%) patients. The recurrence-free and overall survival were significantly shorter in patients with the EZH2 expression than in those without it. A multivariate analysis showed that EZH2 remained an independent prognosticator for recurrence-free and overall survival. Patients with the EZH2-positive lung adenocarcinoma exhibited a significantly higher expression of PD-L1 than did those without it. A logistic regression analysis with backward elimination revealed that the presence of lymphatic and vessel invasion and PD-L1 positivity were independently associated with the EZH2 expression, while age over 70 years, the presence of vessel invasion, wild-type epidermal growth factor receptor, and EZH2 positivity were significantly associated with the PD-L1 expression.

CONCLUSIONS

EZH2-expressing lung adenocarcinomas were shown to express the PD-L1 protein more frequently than were nonexpressing lesions. This study provides the first evidence of a possible association between the EZH2 and PD-L1 expression in patients with resected lung adenocarcinoma.

Efficacy of PD-1 or PD-L1 inhibitors and PD-L1 expression status in cancer: meta-analysis

OBJECTIVE

To evaluate the relative efficacy of programmed cell death 1 (PD-1) or programmed cell death ligand 1 (PD-L1) inhibitors versus conventional drugs in patients with cancer that were PD-L1 positive and PD-L1 negative.

DESIGN

Meta-analysis of randomised controlled trials.

DATA SOURCES

PubMed, Embase, Cochrane database, and conference abstracts presented at the American Society of Clinical Oncology and European Society of Medical Oncology up to March 2018.

REVIEW METHODS

Studies of PD-1 or PD-L1 inhibitors (avelumab, atezolizumab, durvalumab, nivolumab, and pembrolizumab) that had available hazard ratios for death based on PD-L1 positivity or negativity were included. The threshold for PD-L1 positivity or negativity was that PD-L1 stained cell accounted for 1% of tumour cells, or tumour and immune cells, assayed by immunohistochemistry staining methods.

RESULTS

4174 patients with advanced or metastatic cancers from eight randomised controlled trials were included in this study. Compared with conventional agents, PD-1 or PD-L1 inhibitors were associated with significantly prolonged overall survival in both patients that were PD-L1 positive (n=2254, hazard ratio 0.66, 95% confidence interval 0.59 to 0.74) and PD-L1 negative (1920, 0.80, 0.71 to 0.90). However, the efficacies of PD-1 or PD-L1 blockade treatment in patients that were PD-L1 positive and PD-L1 negative were significantly different (P=0.02 for interaction). Additionally, in both patients that were PD-L1 positive and PD-L1 negative, the long term clinical benefits from PD-1 or PD-L1 blockade were observed consistently across interventional agent, cancer histotype, method of randomisation stratification, type of immunohistochemical scoring system, drug target, type of control group, and median follow-up time.

CONCLUSIONS

PD-1 or PD-L1 blockade therapy is a preferable treatment option over conventional therapy for both patients that are PD-L1 positive and PD-L1 negative. This finding suggests that PD-L1 expression status alone is insufficient in determining which patients should be offered PD-1 or PD-L1 blockade therapy.

PD-1/PD-L1 pathway blockade works as an effective and practical therapy for cancer immunotherapy

Cancer immunotherapy has greatly advanced in recent years, and PD-1/PD-L1 blocking therapy has become a major pillar of immunotherapy. Successful clinical trials of PD-1/PD-L1 blocking therapies in cancer treatments have benefited many patients, which promoted the Food and Drug Administration (FDA) approval of PD-1/PD-L1 blocking drugs. In this review, we provide a detailed introduction of five PD-1/PD-L1 blocking drugs, with indications and studies, as a valuable reference for doctors and medical investigators. Moreover, the characteristics of PD-1/PD-L1 blocking therapies, including their universality and sustainability, are discussed in this review. Furthermore, we also discuss and predict the possibility of PD-L1 as an indication marker of PD-1/PD-L1 blocking therapy for pan-cancer treatment, and the current status of combination therapies.