Significance of immune checkpoint proteins in EGFR -mutant non-small cell lung cancer

PD-L1 induces autophagy and primary resistance to EGFR-TKIs in EGFR-mutant lung adenocarcinoma via the MAPK signaling pathway

Resistance to epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) is a significant cause of treatment failure and cancer recurrence in non-small cell lung cancer (NSCLC). Approximately 30% of patients with EGFR-activating mutations exhibit primary resistance to EGFR-TKIs. However, the potential mechanisms of primary resistance to EGFR-TKIs remain poorly understood. Recent studies have shown that increased expression of programmed death ligand-1 (PD-L1) is associated with EGFR-TKIs resistance. Therefore, the present study aimed to investigate the mechanism of PD-L1 in primary resistance to EGFR-TKIs in EGFR-mutant lung adenocarcinoma (LUAD) cells. We found that PD-L1 was associated with poor prognosis in patients with EGFR-mutant LUAD, while the combination of EGFR-TKIs with chemotherapy could improve its therapeutic efficacy. In vitro and in vivo experiments revealed that PD-L1 promoted the proliferation and autophagy and inhibited the apoptosis of LUAD cells. Mechanistic studies demonstrated that upregulation of PD-L1 was critical in inducing autophagy through the mitogen-activated protein kinase (MAPK) signaling pathway, which was beneficial for tumor progression and the development of gefitinib resistance. Furthermore, we found that gefitinib combined with pemetrexed could synergistically enhance antitumor efficacy in PD-L1-overexpression LUAD cells. Overall, our study demonstrated that PD-L1 contributed to primary resistance to EGFR-TKIs in EGFR-mutant LUAD cells, which may be mediated by inducing autophagy via the MAPK signaling pathway. These findings not only help improve the prognosis of patients with EGFR-mutant LUAD but also provide a reference for the research of other cancer types.

Impact of PD-L1 expression on the efficacy of first-line crizotinib in advanced ROS1-rearranged NSCLC

BACKGROUND

The predictive value of programmed death-ligand 1 (PD-L1) expression for the efficacy of tyrosine kinase inhibitors (TKIs) in patients with advanced ROS1-rearranged non-small cell lung cancer (NSCLC) remains underexplored. This study analyzed patients with advanced NSCLC harboring ROS1 rearrangements who received first-line crizotinib to evaluate the correlation between baseline PD-L1 expression and crizotinib efficacy.

METHODS

In this study, the clinical data from 371 patients diagnosed with ROS1-rearranged NSCLC at Shanghai Chest Hospital between November 2017 and December 2022 were reviewed. The patients were categorized into three groups according to the baseline PD-L1 expression: tumor proportion score (TPS) <1%, TPS 1 %-49 %, and TPS≥50 %. The objective response rate (ORR), disease control rate (DCR), and progression-free survival (PFS) following first-line crizotinib treatment were measured.

RESULTS

A total of 64 patients were included in the analysis, with 16 patients in the TPS<1% group, 22 in the TPS 1 %-49 % group, and 26 in the TPS≥50 % group. The overall DCR was 100 %, and the overall ORR was 76.5 %. The ORRs were 81.2 % (13/16) in the TPS<1% group, 63.6 % (14/22) in the TPS 1 %-49 % group, and 84.6 % (22/26) in the TPS≥50 % group (p = 0.218). The median PFS across all patients was 20.21 months (95 % CI: 15.71-24.71), with a median PFS of 28.96 months (95 % CI: 19.87-38.04) in the TPS<1% group, 17.56 months (95 % CI: 12.25-22.86) in the TPS 1 %-49 % group, and 25.85 months (95 % CI: 18.52-33.17) in the TPS≥50 % group (p = 0.100). The median PFS for patients with CD74 fusion was 18.23 months (95 % CI: 15.24-21.22), while those with non-CD74 fusion exhibited a PFS of 16.49 months (95 % CI: 9.75-23.23) (p = 0.359).

CONCLUSION

Patients with advanced ROS1-rearranged NSCLC were found to benefit from first-line crizotinib treatment, irrespective of baseline PD-L1 expression.

Heterogeneity in PD-L1 expression between primary and metastatic lymph nodes: a predictor of EGFR-TKI therapy response in non-small cell lung cancer

BACKGROUND

There is inconclusive evidence to suggest that the expression of programmed cell death ligand 1 (PD-L1) is a putative predictor of response to EGFR-TKI therapy in advanced EGFR-mutant non-small cell lung cancer (NSCLC). We evaluated the heterogeneity in PD-L1 expression in the primary lung site and metastatic lymph nodes to analyze the association between PD-L1 expression and response for patients treated with EGFR-TKI.

METHODS

This study reviewed 184 advanced NSCLC patients with EGFR mutations who received first-generation EGFR-TKI as first-line treatment from 2020 to 2021 at Shanghai Chest Hospital. The patients were divided into the primary lung site group (n = 100) and the metastatic lymph nodes group (n = 84) according to the biopsy site. The patients in each group were divided into TPS < 1%, TPS 1-49%, and TPS ≥ 50% groups according to PD-L1 expression.

RESULTS

The median PFS was 7 (95% CI: 5.7-8.3) months, and the median OS was 26 (95% CI: 23.5-28.5) months for all patients. No correlation existed between PFS or OS and PD-L1 expression. The median PFS in the primary lung site group was 11 months (95% CI: 9.6-12.4) in the TPS < 1% group, 8 months (95% CI: 6.6-9.4) in TPS 1-49% group, and 4 months (95% CI: 3.2-4.8) in TPS ≥ 50% group, with statistically significant differences (p = 0.000). The median OS of the TPS < 1% group and TPS ≥ 50% group showed a statistically significant difference (p = 0.008) in the primary lung site group. In contrast, PD-L1 expression in the lymph nodes of EGFR-mutant patients was unrelated to PFS or OS after EGFR-TKI therapy.

CONCLUSION

PD-L1 expression from the primary lung site might predict clinical benefit from EGFR-TKI, whereas PD-L1 from metastatic lymph nodes did not.

TRIAL REGISTRATION

This retrospective study was approved by the Ethics Committee of Shanghai Chest Hospital (ID: IS23060) and performed following the Helsinki Declaration of 1964 (revised 2008).

The efficacy of furmonertinib in untreated advanced NSCLC patients with sensitive EGFR mutations in a real-world setting: a single institutional experience

Background

Furmonertinib is the standard treatment option in the first-line setting for advanced non-small cell lung cancer (NSCLC) with sensitive epidermal growth factor receptor (EGFR) mutations in China. However, there are limited real-world data available.

Methods

We conducted a retrospective study at a single center, analyzing a cohort of 73 NSCLC patients who tested positive for EGFR mutations and were treated with furmonertinib as their initial therapy between August 2022 and December 2023. The primary endpoint was progression-free survival (PFS), with secondary endpoints including objective response rate (ORR), overall survival (OS), and safety profile.

Results

The median observation period was 9 months (95% confidence interval [CI], 8.0-20.0). The median PFS was 19.5 months (95% CI, 14.6-24.4). OS data were not yet mature. Univariate analysis showed no significant correlation between PFS and factors such as Eastern Cooperative Oncology Group performance status (ECOG PS) score, presence of brain or liver metastases, sex, age, EGFR mutation status, or number of metastatic sites. However, multivariate analysis indicated a potential trend toward extended PFS in patients younger than 65 years (p = 0.053, 95% CI, 0.10-1.02), although the p-value was only marginally significant. The most common adverse events were diarrhea (24%), anemia (36%), and liver injury (32%); however, only four cases experienced severe adverse events.

Conclusion

In a real-world setting, furmonertinib appears to be a favorable treatment option for EGFR-mutated patients. The manageable nature of adverse events further supports its use in clinical practice.

Association of PD-L1 tumor proportion score ≥20% with early resistance to osimertinib in patients with EGFR-mutated NSCLC

BACKGROUND

The relationship between epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) resistance, including osimertinib, and programmed cell death-ligand 1 (PD-L1) expression status in EGFR-mutated non-small cell lung carcinoma (NSCLC) remains unclear.

PATIENTS AND METHODS

We retrospectively analyzed 64 patients with unresectable advanced or metastatic NSCLC carrying EGFR exon 19 deletions (ex19del) or EGFR exon 21 L858R substitutions (L858R) who received osimertinib as the first-line treatment. We compared progression-free survival (PFS) between eligible patients with PD-L1 tumor proportion scores (TPS) ≥20% and PD-L1 TPS <20% using the Kaplan-Meier survival plots with a log-rank test. Multivariate analysis was performed to examine the poor prognostic factors of PFS.

RESULTS

The PD-L1 TPS ≥20% group included 22 cases (median [range] age: 70.5 [33-86] years; 10 women [45.5%]; 11 current or ex-smokers [50%]); ECOG performance status (PS) of 0-1/2/3/4 was noted in 16/4/1/1 patients, respectively. The PD-L1 TPS <20% group included 42 patients (median [range] age 73 [43-88] years; 29 women [69%]; 12 current or ex-smokers [28.6%]); ECOG PS of 0-1/2/3/4 was noted in 33/6/3/0 cases, respectively. The median PFS was 9.1 and 28.1 months in the PD-L1 TPS ≥20% and PD-L1 TPS <20% groups, respectively (log-rank p = 0.013). Multivariate analysis revealed that PD-L1 TPS ≥20% was associated with PFS (hazard ratio: 2.35, 95% confidence interval: 1.09-5.08, p = 0.030).

CONCLUSION

PD-L1 TPS ≥20% in patients with EGFR-mutated NSCLC may be associated with early resistance to osimertinib.

Characterization of TCF-1 and its relationship between CD8+ TIL densities and immune checkpoints and their joint influences on prognoses of lung adenocarcinoma patients

BACKGROUND

T cell factor-1 (TCF-1) + stem-like tumor-infiltrating lymphocytes (stem-like TILs) are important memory cells in the tumor microenvironment. However, their relationship with clinicopathological features, CD8+ TIL densities, immune checkpoint inhibitors (ICs), and prognostic values remain unknown for lung adenocarcinomas (LUADs). In this study, we aimed to characterize TCF-1+ TILs and their prognostic significance in patients with surgically resected LUADs.

METHODS

Expression of TCF-1, CD8, and ICs including programmed death-1 (PD-1), lymphocyte activating-3 (LAG-3), and T cell immunoglobulin and mucin-domain containing-3 (TIM-3) in TILs were estimated using immunohistochemistry of resected LUADs. The association between TCF-1 expressions and clinicopathological characteristics of patient prognoses were analyzed.

RESULTS

Positive TCF-1 expression significantly correlated with advanced pathological stage, tumor grade, CD8+ TILs density, TIM-3 expression, LAG-3 expression, and PD-1 expression. TCF-1 positivity was significantly associated with a better recurrence-free survival (RFS), and overall survival (OS). Subgroup analysis revealed that the TCF-1+/CD8+ group had the best RFS and OS, while the TCF-1-/CD8- group had the worst RFS and OS. Similarly, patients with TCF-1 + PD-1- had the best prognoses and patients with TCF-1-PD-1+ had the worst prognoses.

CONCLUSION

TCF-1 had relatively high positive expression and special clinicopathological features in patients with LUAD. TCF-1+ TILs were related to CD8 density, TIM-3 expression, LAG-3 expression, and PD-1 expression, and were associated with better prognoses in LUAD patients. A combination of TCF-1 and CD8 densities or PD-1 expression further stratified patients into different groups with distinct prognoses.

Influence of PD-L1 expression on the efficacy of EGFR-TKIs in EGFR-mutant non-small cell lung cancer

BACKGROUND

Evidence on the influence of programmed death-ligand 1 (PD-L1) expression on the efficacy of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) in EGFR-mutant non-small cell lung cancer (NSCLC) patients is at variance.

METHODS

A single-center retrospective study was conducted to evaluate the influence of PD-L1 expression on the efficacy of EGFR-TKIs for NSCLC patients with EGFR mutation. Clinical information was retrieved from electronic medical records. The patients were divided into three subgroups according to PD-L1 expression level: PD-L1 < 1% (negative), PD-L1 1%-49% and PD-L1 ≥ 50%. The clinicopathological features, overall response rate (ORR), progression-free survival (PFS) and comutation information were collected and compared between the three subgroups.

RESULTS

A total of 117 patients were included. For PD-L1 < 1%, PD-L1 1%-49% and PD-L1 ≥ 50% group, there were 39 (33.3%), 51 (43.5%) and 27 (23.0%) patients respectively, and the ORR was 43.2%, 64.0%, and 51.9%, respectively (p = 0.162), and the median progression-free survival (mPFS) was 22.0 months (95% CI: 14.0-29.9 months), 15.4 months (95% CI: 8.9-21.8 months) and 13.0 months (95% CI: 10.6-15.3 months), respectively (log-rank, p = 0.01). The mPFS was negatively correlated with PD-L1 expression level (r = -0.264, p = 0.041) and PD-L1 expression was an independent risk factor for worse PFS of EGFR-TKIs in multivariate Cox regression. Patients with concurrent TP53 mutation had shorter PFS (p = 0.039) and the patients harboring both mutant TP53 and positive PD-L1 had the shortest PFS (p = 0.006).

CONCLUSIONS

The efficacy of EGFR-TKIs was influenced by the baseline PD-L1 expression. Higher PD-L1 expression was associated with shorter PFS. The combined indicators of TP53 and PD-L1 identified subgroups showing divergent benefits from EGFR-TKIs.

Effect of BIM expression on the prognostic value of PD-L1 in advanced non-small cell lung cancer patients treated with EGFR-TKIs

The role of Programmed Cell Death Ligand 1 (PD-L1) expression in predicting epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKIs) efficacy remains controversial. Recent studies have highlighted that tumor-intrinsic PD-L1 signaling can be modulated by STAT3, AKT, MET oncogenic pathway, epithelial-mesenchymal transition, or BIM expression. This study aimed to investigate whether these underlying mechanisms affect the prognostic role of PD-L1. We retrospectively enrolled patients with EGFR mutant advanced stage NSCLC who received first-line EGFR-TKI between January 2017 and June 2019, the treatment efficacy of EGFR-TKI was assessed. Kaplan-Meier analysis of progression-free survival (PFS) revealed that patients with high BIM expression had shorter PFS, regardless of PD-L1 expression. This result was also supported by the COX proportional hazard regression analysis. In vitro, we further proved that the knockdown of BIM, instead of PDL1, induced more cell apoptosis following gefitinib treatment. Our data suggest that among the pathways affecting tumor-intrinsic PD-L1 signaling, BIM is potentially the underlying mechanism that affects the role of PD-L1 expression in predicting response to EGFR TKI and mediates cell apoptosis under treatment with gefitinib in EGFR-mutant NSCLC. Further prospective studies are required to validate these results.

Crosstalk between the B7/CD28 and EGFR pathways: Mechanisms and therapeutic opportunities

Somatic activating mutations in the epidermal growth factor receptor (EGFR) are one of the most common oncogenic drivers in cancers such as non-small-cell lung cancer (NSCLC), metastatic colorectal cancer, glioblastoma, head and neck cancer, pancreatic cancer, and breast cancer. Molecular-targeted agents against EGFR signaling pathways have shown robust clinical efficacy, but patients inevitably experience acquired resistance. Although immune checkpoint inhibitors (ICIs) targeting PD-1/PD-L1 have exhibited durable anti-tumor responses in a subset of patients across multiple cancer types, their efficacy is limited in cancers harboring activating gene alterations of EGFR. Increasing studies have demonstrated that upregulation of new B7/CD28 family members such as B7-H3, B7x and HHLA2, is associated with EGFR signaling and may contribute to resistance to EGFR-targeted therapies by creating an immunosuppressive tumor microenvironment (TME). In this review, we discuss the regulatory effect of EGFR signaling on the PD-1/PD-L1 pathway and new B7/CD28 family member pathways. Understanding these interactions may inform combination therapeutic strategies and potentially overcome the current challenge of resistance to EGFR-targeted therapies. We also summarize clinical data of anti-PD-1/PD-L1 therapies in EGFR-mutated cancers, as well as ongoing clinical trials of combination of EGFR-targeted therapies and anti-PD-1/PD-L1 immunotherapies.

Osimertinib as first-line treatment for advanced epidermal growth factor receptor mutation-positive non-small-cell lung cancer in a real-world setting (OSI-FACT)

BACKGROUND

Osimertinib is the standard of care in the initial treatment for advanced epidermal growth factor receptor (EGFR) mutation-positive lung cancer. However, clinical data and reliable prognostic biomarkers are insufficient.

METHODS

We performed a retrospective multicentre cohort study for 538 EGFR mutation-positive patients, who received osimertinib as the initial treatment between August 2018 and December 2019. The main outcome was progression-free survival (PFS).

RESULTS

The median observation period was 14.7 months (interquartile range 11.4-20.0). The median PFS was 20.5 months (95% confidence interval [CI] 18.6-not reached). Multivariate analysis showed that sex (male) (hazard ratio [HR] 1.99, 95% CI 1.35-2.93, P = 0.001), malignant effusions (HR 1.51, 95% CI 1.11-2.04, P = 0.008), liver metastasis (HR 1.55, 95% CI 1.03-2.33, P = 0.037), advanced unresectable cases (HR 1.71, 95% CI, 1.04-2.82, P = 0.036), mutation type and programmed cell death-ligand 1 (PD-L1) expression were associated with PFS. The L858R (HR 1.55, 95% CI 1.01-2.38, P = 0.043) and uncommon mutations (HR 3.15, 95% CI 1.70-5.83, P < 0.001) were associated with PFS. PD-L1 expression of 1-49% (HR 1.66, 95% CI 1.05-2.63, P = 0.029), ≥50% (HR 2.24, 95% CI 1.17-4.30, P = 0.015) and unknown (HR 1.53, 95% CI 1.05-2.22, P = 0.026) was associated with PFS. The main reasons for treatment discontinuation among 219 patients were disease progression (44.3%), pneumonitis (25.5%) and other adverse events (16.0%).

CONCLUSION

During initial treatment with osimertinib, PD-L1 expression is significantly related to PFS. Adverse events are a noteworthy reason for discontinuation.

Small molecule tyrosine kinase inhibitors modulated blood immune cell counts in patients with oncogene-driven NSCLC

BACKGROUND

Lack of biomarkers and in vitro models has contributed to inadequate understanding of the mechanisms underlying the inferior clinical response to immune checkpoint inhibitors (ICIs) in patients with oncogene-driven non-small cell lung cancer (NSCLC).

METHODS

The effect of small molecule tyrosine kinase inhibitors (TKIs) on peripheral blood mononuclear cells (PBMCs) in 34 patients with oncogene-driven NSCLC (cohort A) was compared with those from 35 NSCLC patients without oncogene-driven mutations received ICI (cohort B) or from 22 treatment-naïve NSCLC patients (cohort C). Data for each blood biomarker were summarized by mean and standard deviation and compared by Wilcoxon rank sum tests or Kruskal-Wallis tests with significance at 2-sided p value < 0.05. Co-culture of PBMCs and pleural effusion-derived tumor cells from individual patients with oncogene-driven NSCLC was used to determine the in vitro cytotoxicity of TKI and ICI.

RESULTS

Except for low CD3% in cohort A, there were no significant differences in other 12 blood biomarkers among the 3 cohorts at baseline. TKI treatment in cohort A was associated with significant increase in CD3% and decrease in total and absolute neutrophils (p < 0.05). In cohort B, patients with good clinical response to ICI treatment (N = 18) had significant increases in absolute lymphocyte counts (ALCs), CD4 and/or CD8 cell counts. Conversely, those patients with poor clinical response to ICI (N = 17) had significant decreases in these cell counts. Of the 27 patients with pre- and post-treatment blood samples in cohort A, 11 had poor clinical response to TKIs and decreased lymphocyte counts. Of the remaining 16 patients who had good clinical response to TKI therapy, 10 (62.5%) patients had decreased, and 6 (37.5%) patients had increased lymphocyte counts. Multicolor immunophenotyping of PBMCs revealed ICI treatment activated additional immune cell types that need further validation. We confirmed that TKI treatment could either antagonize or enhance the effect of ICIs in the co-culture assay using patient's tumor cells and PBMCs.

CONCLUSIONS

To the best of our knowledge, this is the first study showing that TKIs can have various effects on blood immune cells, which may affect their response to ICIs. Further validation of the blood biomarker and in vitro assay is warranted.

Characterization of CD66b and its relationship between immune checkpoints and their synergistic impact in the prognosis of surgically resected lung adenocarcinoma

OBJECTIVES

CD66b positive tumor-infiltrating neutrophils (TINs) are key immunity cells in the tumor microenvironment (TME). However, their relationship with clinicopathological features, immune checkpoints (ICs), and prognostic value remains undetermined in lung adenocarcinoma (LUAD). In this study, we aimed to characterize the infiltration by TINs and the prognostic significance in patients with surgically resected LUAD.

MATERIALS AND METHODS

Expression of CD66b and ICs, including PD-L1, PD-1, CTLA4, LAG3, TIM3, TIGIT, VISTA, and BTLA, in both cancer cell and tumor-infiltrating lymphocytes (TILs) were estimated by immunohistochemistry in resected LUAD. The associations between CD66b expression and clinicopathological characteristics in patient prognoses were analyzed. We also verified results in another cohort from 85 patients with untreated LUAD and further analyzed the correlation between CD66b expression and EGFR and KRAS mutation status in addition to the rearrangement of the anaplastic lymphoma receptor tyrosine kinase gene (ALK).

RESULTS

A total of 240 patients were included in this study. CD66b expression was observed in 87 (36.2%) samples. ICs including PD-L1, PD-1, CTLA4, LAG3, TIM3, TIGIT, VISTA, and BTLA were observed in percentages that ranged from 23.8% to 59.4%. Positive CD66b expression significantly correlated with smoking history (p = 0.029), pathological stage (p = 0.040), and the positive expression of LAG-3 (p < 0.001), PD-1 (p = 0.008), CTLA-4 (p = 0.013), TIM-3 (p = 0.025), TIGIT (p = 0.002), PD-L1 in TILs (p = 0.015), and PD-L1 in tumor cells (p = 0.010). CD66b positivity was significantly associated with worse recurrence-free survival (RFS) (hazard ratio, HR, 1.687; 95% confidence interval, CI, 1.058-2.690, p = 0.028) and overall survival (OS) (HR, 1.667; 95% CI, 1.097-2.534, p = 0.017). Subgroup analysis revealed that the CD66b+/LAG-3 + group had the worst RFS (5-year rate: 39.5%,) and OS (5-year rate: 53.7%,), while the CD66b-/LAG-3 - group had the best RFS (5-year rate: 65.6%) and OS (5-year rate: 78.8%). The p value in analysis of RFS and OS was 0.005 and 0.008, respectively. In the verification set, high expression of CD66b was also significantly correlated with the positive expression of LAG-3 (p < 0.001), PD-1 (p = 0.002), CTLA-4 (p = 0.034), TIM-3 (p = 0.049), PD-L1 in TILs (p = 0.003), and PD-L1 in tumor cells (p = 0.045). There was no correlation between CD66b expression and positive TIGIT expression (p = 0.077), EGFR mutation (p = 0.223), KRAS mutation (p = 0.151), and ALK fusion (p = 0.310).

CONCLUSION

CD66b had a relatively high positive expression rate and special clinicopathological features in patients with LUAD. CD66b + TINs were related to the expression of ICs and associated with poor prognoses in LUAD. A combination of CD66b and ICs, especially LAG-3 could further stratify patients into different groups with distinct prognoses.

The predictive and prognostic effects of PD-L1 expression on TKI treatment and survival of EGFR-mutant NSCLC: A meta-analysis

ABSTRACT

Whether programmed death-ligand 1 (PD-L1) expression could predict the outcome of tyrosine kinase inhibitor (TKI) treatment and prognosis of epidermal growth factor receptor (EGFR)-mutant nonsmall cell lung cancer (NSCLC) is remaining controversial.Potential studies were search from PubMed, Embase, and Web of Science databases. Pooled odds ratio of objective response rate was used to describe the relationship between PD-L1 expression and primary resistance to EGFR-TKIs. Pooled hazard ratios (HRs) of progression-free survival (PFS) and overall survival (OS) were included to assess the effects of PD-L1 status on the outcome of EGFR-TKI treatment and survival of EGFR-mutant NSCLCs.Eighteen eligible studies (1986 EGFR-mutant NSCLCs) were included in this meta-analysis. Positive PD-L1 expression correlated with lower objective response rate of EGFR-TKI treatment (odds ratio [95% confidence interval {CI}] = 0.52 [0.28-0.98], P = .043), while PFS (adjusted HR [95% CI] = 1.49 [0.96-1.89], P = .332) and OS (HR [95% CI] = 1.24 [0.70-2.20], P = .456) of EGFR-TKI treatment did not correlated with PD-L1 status. Furthermore, PD-L1 expression was not a predictive biomarker for the OS (HR [95% CI] = 1.43 [0.98-2.08], P = .062) in overall EGFR-mutant cohort.Positive PD-L1 expression indicated a higher incidence of primary resistance, but did not correlate with the PFS or OS of EGFR-TKI therapy. In addition, PD-L1 expression was unlikely a predictive biomarker for prognosis of EGFR-mutant NSCLCs.

Predictive value of pretreatment PD-L1 expression in EGFR-mutant non-small cell lung cancer: a meta-analysis

Objective

To investigate the predictive value of programmed death-ligand 1 (PD-L1) expression in non-small cell lung cancer (NSCLC) patients treated with epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs).

Methods

We conducted a systemic search of PubMed, EMBASE, and the Cochrane Library from 1 January 2000 to 30 August 2020, to identify related studies. We combined the hazard ratio (HR) and 95% confidence interval (CI) to assess the correlation of PD-L1 expression with progression-free survival (PFS) and overall survival (OS). We assessed the quality of the included studies by the Newcastle–Ottawa Scale (NOS). We performed subgroup analyses based on immunohistochemistry (IHC) scoring system, IHC antibodies, sample size, countries, and survival analysis mode. Sensitivity analysis and evaluation of publication bias were also performed.

Results

Twelve studies including 991 patients met the criteria. The mean NOS score was 7.42 ± 1.19. Patients with high PD-L1 expression was associated with poorer PFS (HR = 1.90; 95% CI = 1.16–3.10; P = 0.011), while there was no association between PD-L1 expression and OS (HR = 1.19; 95% CI = 0.99–1.43; P = 0.070). Subgroup analysis prompted IHC scoring systems, IHC antibodies, and sample size have important effects on heterogeneity. The pooled results were robust according to the sensitivity analysis.

Conclusions

The result of this meta-analysis suggested that PD-L1 expression might be a predictive biomarker for EGFR-mutant non-small cell lung cancer treated with EGFR-TKIs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-021-02254-x.

Relationship between PD-L1 expression and outcome in EGFR-mutant lung cancer patients treated with EGFR tyrosine kinase inhibitors

OBJECTIVES

Predictive biomarkers for poor response to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) is an area of ongoing research. This multicentre retrospective study sought to determine the impact of programmed death-ligand 1 (PD-L1) tumour proportional score (TPS) on outcome in EGFR TKI treated patients.

MATERIALS AND METHODS

Patients with Stage IIIB/IV lung adenocarcinoma harbouring a sensitising EGFR mutation treated with first-line TKI at five metropolitan hospitals were included. PD-L1 TPS was determined using the Ventana anti-PD-L1 (SP263) assay. High PD-L1 expression was defined as TPS ≥ 50 %. Determinants of progression and survival hazards were modelled using Cox regression.

RESULTS

A total of 186 patients were included. Mean age was 67 years, 66 % were female and 54 % were Asian. Patients with high PD-L1 expression (n = 23; 12 %) had significantly shorter progression free survival (6.6 vs 13.0 months, hazard ratio (HR) 2.6 95 % CI 1.6-4.2, p < 0.0001) and overall survival (11.5 vs 32.9 months, HR 3.3, 95 % CI 1.9-5.7, p < 0.0001) compared to patients with PD-L1 low/negative tumours. This remained significant in multivariate analyses. High PD-L1 in post-TKI progression biopsies was not associated with poorer survival.

CONCLUSION

In this large, real-world cohort of EGFR-mutant lung adenocarcinoma patients, high PD-L1 expression was associated with early resistance to 1st generation EGFR TKIs and shorter survival, regardless of ethnicity.

Development of EGFR TKIs and Options to Manage Resistance of Third-Generation EGFR TKI Osimertinib: Conventional Ways and Immune Checkpoint Inhibitors

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) have been first-line therapy in the treatment of non-small cell lung cancer (NSCLC) harboring EGFR sensitive mutations. Progression inevitably happens after 10–14 months of first- or second-generation EGFR TKIs treatment for acquired resistance. Owing to the successful identification of EGFR T790M, third-generation EGFR TKIs such as osimertinib were developed to target such resistance mutation. Nowadays, osimertinib has shown its efficacy both in first-line and second-line after resistance to previous generations of TKI treatment of EGFR-mutant NSCLC. However, drug resistance also emerges on third-generation EGFR TKIs. Multiple mechanisms of acquired resistance have been identified, and some novel strategies were reported to overcome third-generation TKI resistance. Immune checkpoint inhibitors (ICIs) have dramatically changed the prognosis of selected patients. For patients with EGFR-addicted metastatic NSCLC, ICIs have also revealed a potential role. In this review, we will take stock of mechanisms of acquired resistance to third-generation TKIs and discuss current challenges and future perspectives in clinical practice.

Concurrent Genetic Alterations and Other Biomarkers Predict Treatment Efficacy of EGFR-TKIs in EGFR-Mutant Non-Small Cell Lung Cancer: A Review

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) greatly improve the survival and quality of life of non-small cell lung cancer (NSCLC) patients with EGFR mutations. However, many patients exhibit de novo or primary/early resistance. In addition, patients who initially respond to EGFR-TKIs exhibit marked diversity in clinical outcomes. With the development of comprehensive genomic profiling, various mutations and concurrent (i.e., coexisting) genetic alterations have been discovered. Many studies have revealed that concurrent genetic alterations play an important role in the response and resistance of EGFR-mutant NSCLC to EGFR-TKIs. To optimize clinical outcomes, a better understanding of specific concurrent gene alterations and their impact on EGFR-TKI treatment efficacy is necessary. Further exploration of other biomarkers that can predict EGFR-TKI efficacy will help clinicians identify patients who may not respond to TKIs and allow them to choose appropriate treatment strategies. Here, we review the literature on specific gene alterations that coexist with EGFR mutations, including common alterations (intra-EGFR [on target] co-mutation, TP53, PIK3CA, and PTEN) and driver gene alterations (ALK, KRAS, ROS1, and MET). We also summarize data for other biomarkers (e.g., PD-L1 expression and BIM polymorphisms) associated with EGFR-TKI efficacy.

Impact of programmed death-ligand 1 expression on the patients of stage IV non-small cell lung cancer harboring epidermal growth factor receptor mutation: a systematic review and meta-analysis

BACKGROUND

To determine the impact of programed death-ligand 1 (PD-L1) expression on progression-free survival (PFS) outcomes in stage IV epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC) treated with first-line EGFR tyrosine kinase inhibitors (TKIs).

MATERIAL AND METHODS

We searched biomedical databases for studies comparing PFS outcomes of PD-L1-positive versus (vs) PD-L1-negative tumors. We assessed the methodological quality of eligible studies using ROBINS-I tool. We employed a two-staged meta-analysis approach by reconstructing individual patient data of each study from the published Kaplan-Meier curves and then pooling the individual hazard ratios (HRs) and weighted mean differences (WMDs) for restricted mean PFS time at 6 (RMPFST6) and 12 (RMPFST12) months using random-effect models. We assessed the quality of summarized evidence using GRADE approach.

RESULTS

We identified five non-randomized comparative studies including 435 patients. The overall risk of bias in the methodological quality of included studies was moderate. PD-L1-positive tumors were associated with significantly worse PFS outcomes compared to PD-L1-negative tumors (HR: 2.41, 95% confidence interval (CI): 1.59-3.66, p < .001; WMD in RMPFST6: -1.01, 95% CI: -1.65 to -0.37, p = .002; WMD in RMPFST12: -2.64, 95% CI: -4.40 to -0.88, p = .003). Subgroup analysis showed that the effect of PD-L1 expression on PFS outcomes was greater for studies using older-generation rather than third-generation TKIs (HR: 2.69 vs 1.22, p = .069; WMD in RMPFST6: -1.23 vs -0.07, p = .005; WMD in RMPFST12: -3.29 vs -0.12, p = .003). The quality of summarized evidence was judged to be low.

CONCLUSION

There is low certainty in the evidence to suggest that positive PD-L1 expression is associated with inferior disease control and survival outcomes in patients with stage IV EGFR-mutated NSCLC treated with first-line EGFR TKIs.

Association of Tumor PD-L1 Expression with the T790M Mutation and Progression-Free Survival in Patients with EGFR-Mutant Non-Small Cell Lung Cancer Receiving EGFR-TKI Therapy

Background: Among patients with non-small cell lung cancer (NSCLC), we compared the progression-free survival (PFS) and proportion of acquisition of T790M mutation of the epidermal growth receptor gene (EGFR) after first-line treatment with epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) in patient groups with and without tumor expression of programmed death ligand-1 (PD-L1). Methods: Data of patients with EGFR-mutant NSCLC were retrospectively analyzed. Tumor PD-L1 expression was evaluated by immunohistochemistry using the 22C3 antibody. T790M gene mutation was evaluated by Cobas EGFR assay using tissues or humoral specimens. Results: Data of 47 patients with EGFR-mutant NSCLC were analyzed. The median (95% confidence interval) PFS in the PD-L1-negative and -positive patient groups were 12.9 (9.7–15.4) months and 9.0 (5.1–12.3) months, respectively (p = 0.029). T790M gene mutation was analyzed in 27 patients. The proportion of acquisition of T790M mutation of EGFR after first-line treatment with an EGFR-TKI was higher in the PD-L1-negative patient group than in the PD-L1-positive patient group (8/11 patients (72.7%) vs. 4/16 patients (25.0%); p = 0.022). Conclusions: Patients with negative tumor PD-L1 expression showed longer PFS and a higher proportion of acquisition of T790M mutation of EGFR after first-line treatment with an EGFR-TKI.

[Advances in Combination Therapy of Immune Checkpoint Inhibitors for Lung Cancer]

Immune checkpoint inhibitors (ICIs) therapy is the most commonly used immunotherapy regimen at present. It has been approved for clinical treatment of melanoma, kidney cancer, head and neck cancer, bladder cancer and other tumors. It has made a breakthrough in the treatment of lung cancer and become a new pillar of comprehensive treatment of lung cancer. However, ICIs alone is less effective in non-selective patients, and combination therapy has become a hot topic of exploration. This article focuses on the development of combined immune checkpoint inhibitors and describes how immunotherapy can be used to treat early stage cancer.

High PD-L1 Expression is Associated with Unfavorable Clinical Outcome in EGFR-Mutated Lung Adenocarcinomas Treated with Targeted Therapy

Purpose

Although programmed death-ligand 1 (PD-L1) expression is widely accepted as a predictive and prognostic biomarker in immunotherapy, its implications in lung cancer patients with driving mutations are still unclear. The objective of this study is to determine the association between PD-L1 expression and treatment outcome in epidermal growth factor receptor (EGFR)-mutated lung cancer treated with tyrosine kinase inhibitors (TKIs).

Methods

We retrospectively enrolled EGFR-mutant, advanced lung adenocarcinoma patients who received first-line EGFR-TKIs and evaluated the PD-L1 tumor proportion score (TPS) using the 22C3 pharmDx assay. We investigated the distribution of patients with different PD-L1 TPS values, followed by the analysis of response rate (RR), survival rate, and incidence of secondary T790M mutation according to the PD-L1 TPS group.

Results

Among the 131 patients analyzed, the proportion of patients with PD-L1 TPS ≥ 50%, 1–49%, and <1%, was 17.6%, 32.8%, and 49.6%, respectively. The RR was significantly lower in the group with PD-L1 TPS ≥ 50% than in the other groups (43.5% vs 72.1% vs 78.5%, all p = 0.001). In multivariate analysis, PD-L1 TPS ≥ 50% was independently associated with a significantly shorter PFS in the overall population (hazard ratio [HR] = 2.64, p = 0.004) and associated with shorter OS in patients with exon 19 deletion (HR = 2.55, p = 0.041) compared with PD-L1 TPS < 50%. In addition, the frequency of secondary T790M mutation after TKI failure was significantly lower in the group with PD-L1 TPS ≥ 50% than in the other groups (13.3% vs 40.0% vs 53.3%, all p = 0.001). PD-L1 TPS ≥ 50% was an independent predictor of a lower frequency of this mutation (HR = 0.63, p = 0.043).

Conclusion

High PD-L1 expression was associated with unfavorable clinical outcome and less development of secondary T790M mutation, suggesting a distinct subgroup warranting active surveillance and tailored therapeutic approach.

Association of Programmed Death-Ligand 1 Expression with Fusion Variants and Clinical Outcomes in Patients with Anaplastic Lymphoma Kinase-Positive Lung Adenocarcinoma Receiving Crizotinib

BACKGROUND

Programmed death-ligand 1 (PD-L1) expression is associated with clinical outcomes of epidermal growth factor receptor (EGFR) mutant lung adenocarcinoma (ADC) treated with tyrosine kinase inhibitors (TKIs). However, whether PD-L1 expression plays a role in anaplastic lymphoma kinase (ALK)-positive lung ADC is unknown. We aimed to evaluate the impact of PD-L1 in patients with ALK-positive lung ADC receiving crizotinib.

MATERIALS AND METHODS

PD-L1 expression was identified by immunohistochemistry (IHC). Reverse transcriptase-polymerase chain reaction was used for ALK variant detection, and immunofluorescence-based multiplex staining was applied for exploring immune cells in tumor microenvironments.

RESULTS

A total of 78 patients with ALK-positive advanced ADC were enrolled in our study, of whom 52 received crizotinib. Compared with EGFR/ALK wild-type tumors, PD-L1 expression was lower in ALK-positive ADC. ALK fusion variants were identified in 32 patients, and those with variant 3 and 5 (short variants) had higher PD-L1 expression than those with other variants. The crizotinib objective response rate (ORR) and progression-free survival (PFS) was better in tumors with negative PD-L1 expression (ORR/PFS in PD-L1 0% vs. 1%-49% vs. 50%-100%: 60.7%/11.8 months vs. 38.5%/6.5 months vs. 36.4%/4.0 months, p = .007/.022). The multivariate Cox proportional hazards model revealed that PD-L1 0% (vs. ≥1%) was an independent factor for longer PFS (adjusted hazard ratio 0.322, 95% confidence interval 0.160-0.650, p = .002). Multiplex IHC in three cases showed a varied extent of immune cell infiltrations in tumors with different PD-L1 expression.

CONCLUSION

Positive PD-L1 expression was associated with unfavorable clinical outcomes in patients with ALK-positive lung ADC receiving crizotinib.

IMPLICATIONS FOR PRACTICE

Not all lung adenocarcinoma with sensitizing driver mutations experienced durable responses to small-molecule tyrosine kinase inhibitors (TKIs). Similar to the negative impact of programmed death-ligand 1 (PD-L1) in epidermal growth factor receptor mutant tumors treated with TKIs, this study demonstrated that positive PD-L1 expression was also associated with worse response rate and shorter progression-free survival of anaplastic lymphoma kinase (ALK)-positive adenocarcinoma treated with crizotinib. Among different ALK fusion partners, tumors with short variants (V3 and V5) had higher PD-L1 compared with long variants (V1, V2, and V6). Testing PD-L1 before initiating crizotinib for ALK-positive lung cancer could be a simple method to provide important prognostic information.

First-line immune checkpoint therapy in metastatic squamous cell lung cancer harboring both EGFR mutation and high expression of PD-L1: A case report

A 90-year-old female was admitted to our hospital with a history of a dry cough. Chest computed tomography (CT) scan showed a tumor shadow, and CT-guided lung biopsy revealed squamous cell carcinoma harboring an EGFR mutation. In addition, programmed death-ligand 1 (PD-L1) was highly expressed with a tumor proportion score (TPS) of >75%. Pembrolizumab therapy in the first-line setting was not effective, and the patient died at six months from the first visit. Squamous cell lung cancers (SCLCs) with both EGFR mutation and high expression of PD-L1 are very rare.

EGFR mutation: novel prognostic factor associated with immune infiltration in lower-grade glioma; an exploratory study

BACKGROUND

Glioma is one of the most common type of primary central nervous system tumors. EGFR mutation, a common alteration occurs in various tumors, is not brought to the forefront in understanding and treating glioma at present.

METHODS

In the present study, we demonstrated an immune infiltration related pattern of EGFR mutation in lower-grade glioma. In silico analyses were performed to investigate EGFR mutation and its biological effects and clinical values. GO and GSEA process were used as enrichment analysis. Infiltration levels of specific types of immune cells were estimated at TIMER database. Clinical data of patients were obtained from TCGA and were employed for survival analyses.

RESULTS

Here we revealed that EGFR mutation leads to an up-regulation of immune response related pathways and dismal prognosis in lower-grade glioma. Infiltration of CD4+ T cells, neutrophils, macrophages, and dendritic cells were significantly increased in EGFR-mutant cases. Infiltration of specific types of immune cells were correlated with shorter survival time. PD-L1 was elevated in EGFR-mutant cases and correlated with infiltration level of CD4+ T cells, neutrophils and dendritic cells.

CONCLUSION

EGFR mutation indicates increasing infiltration of specific types of immune cells and poor prognosis in lower-grade glioma. Alteration of immune microenvironment since the EGFR mutation might influence the survival of glioma. We also provided a novel evidence and indicator of PD-1 inhibitor application in glioma.

The canonical TGF-β/Smad signalling pathway is involved in PD-L1-induced primary resistance to EGFR-TKIs in EGFR-mutant non-small-cell lung cancer

Background

Approximately 30% of patients with epidermal growth factor receptor (EGFR)-activating mutations have no response to EGFR-tyrosine kinase inhibitors (TKIs) (primary resistance). However, little is known about the molecular mechanism involved in primary resistance to EGFR-TKIs in EGFR-mutant non-small cell lung cancer (NSCLC). Programmed death ligand-1 (PD-L1) plays important regulatory roles in intracellular functions and leads to acquired resistance to EGFR-TKIs in NSCLC. Here, we investigated the mechanistic role of PD-L1 in primary resistance to EGFR-TKIs in EGFR-mutant NSCLC cells.

Methods

The expression levels of PD-L1 and the sensitivity to gefitinib in H1975, HCC827 and PC-9 cells were determined by quantitative real-time PCR analysis (qRT-PCR) and Cell Counting Kit-8 (CCK-8) assays, respectively. Molecular manipulations (silencing or overexpression) were performed to assess the effect of PD-L1 on sensitivity to gefitinib, and a mouse xenograft model was used for in vivo confirmation. Western blotting and qRT-PCR were used to analyse the expression of epithelial-mesenchymal transition (EMT) markers. The effect of PD-L1 on migratory and invasive abilities was evaluated using the Transwell assay and mice tail intravenous injection.

Results

Higher expression of PD-L1 was related to less sensitivity to gefitinib in EGFR-mutant NSCLC cell lines. The overexpression or knockdown of PD-L1 presented diametrical sensitivity to gefitinib in vitro and in vivo. Furthermore, the overexpression of PD-L1 led to primary resistance to gefitinib through the induction of EMT, which was dependent on the upregulation of Smad3 phosphorylation. Moreover, in the mouse model, the knockdown of PD-L1 inhibited transforming growth factor (TGF)-β1-induced cell metastasis in vivo.

Conclusion

PD-L1 contributes to primary resistance to EGFR-TKI in EGFR-mutant NSCLC cells, which may be mediated through the induction of EMT via the activation of the TGF-β/Smad canonical signalling pathway.

Monitoring the Response of PD-L1 Expression to Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors in Nonsmall-Cell Lung Cancer Xenografts by Immuno-PET Imaging

Accumulating evidence has suggested that the tumor microenvironment of nonsmall-cell lung cancer (NSCLC) may be impacted by chemotherapy, radiotherapy, or epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). PD-L1 is an important biomarker in the tumor microenvironment that can predict patient response to immunotherapies. Therefore, it is highly desirable to achieve a real-time, noninvasive assessment of PD-L1 expression, which can provide critical information for recruiting patients as well as monitoring therapeutic efficacy. We herein studied the EGFR-TKI-induced effects on PD-L1 levels in NSCLC tumor models using immuno-PET imaging with ⁸⁹Zr-Df-KN035, an imaging tracer previously established by our group. A549 human NSCLC xenografts were established in BALB/c nude mice and treated with different doses of an EGFR-TKI gefitinib. PET imaging with ⁸⁹Zr-Df-KN035 was performed before and after the treatment to evaluate PD-L1 expression, which was further verified by immunohistochemical staining. Our results demonstrate that ⁸⁹Zr-Df-KN035 can specifically evaluate PD-L1 levels in NSCLC tumor models. Compared to the untreated control, the high dose of gefitinib inhibited tumor growth and lowered the tumor uptake of ⁸⁹Zr-Df-KN035. In comparison, the low dose of gefitinib did not affect tumor growth, although the extensive tumor necrosis also led to the lower uptake of ⁸⁹Zr-Df-KN035. In conclusion, our results demonstrate that immuno-PET imaging with ⁸⁹Zr-Df-KN035 is a promising tool to noninvasively monitor PD-L1 expression in NSCLC treated with EGFR-TKIs and can be used to optimize treatment plans for immunotherapy.

EGFR exon 21 L858R as an acquired resistance mechanism to nivolumab in a lung cancer patient originally driver gene-negative

The use of immune checkpoint inhibitors targeting PD‐1 and PD‐L1 in advanced non‐small cell lung cancer (NSCLC) has been one of the most significant improvements in recent years. However the resistance mechanisms of immune checkpoint inhibitors require further investigation. Herein we attempted to determine the possible resistance mechanism of nivolumab in a male smoker with advanced adenosquamous carcinoma. After experiencing disease progression on systematic chemotherapy, he was administered nivolumab as a result of high PD‐L1 expression. Larger panel gene detection was performed after the failure of nivolumab treatment to investigate the possible resistance mechanism and a new EGFR exon 21 L858R mutation was detected. After a achieving a response with gefitinib, the patient suffered a rapid relapse and died of tumor progression. This case represents the first time EGFR exon 21 L858R has been detected as an acquired resistance mutation to nivolumab. Patients with high PD‐L1 expression may exhibit a poor response to EGFR‐tyrosine kinase inhibitors. Large panel gene detection remains the optimal choice when confronted with drug resistance.

T-Cell Immunoglobulin Mucin 3 Expression on Tumor Infiltrating Lymphocytes as a Positive Prognosticator in Triple-Negative Breast Cancer

Purpose

T-cell immunoglobulin and mucin domain-containing molecule 3 (TIM-3) is an emerging immune response molecule related to T-cell anergy. There has been tremendous interest in breast cancer targeting immune checkpoint molecules, especially in the triple-negative breast cancer (TNBC). This study was designed to investigate TIM-3 expression on tumor infiltrating lymphocytes (TILs), its relationships with clinicopathological para-meters and expression of programmed death receptor 1 (PD-1)/programmed death receptor ligand 1 (PD-L1), and its prognostic role.

Methods

Immunohistochemistry on tissue microarray blocks produced from 109 samples of invasive ductal carcinoma type TNBC was performed with antibodies toward TIM-3, PD-1, PD-L1 and breast cancer-related molecular markers. Associations between their expression and clinicopathological parameters as well as survival analyses were performed.

Results

TIM-3 was expressed in TILs from all 109 TNBCs, consisting of 17 cases (<5%), 31 cases (6%–25%), 48 cases (26%–50%), and 13 cases (>51%). High TIM-3 was significantly correlated with younger patients (p=0.0101), high TILs (p=0.0029), high tumor stage (p=0.0018), high PD-1 (p=0.0001) and high PD-L1 (p=0.0019), and tended to be associated with higher histologic grade, absence of extensive in situ components and microcalcification. High TIM-3 expression was significantly associated with a combinational immunophenotype group of high PD-L1 and high PD-1 (p<0.0001). High TIM-3 demonstrated a significantly better disease-free survival (DFS) (p<0.0001) and longer overall survival (OS) (p=0.0001), together with high TILs and high PD-1. In univariate survival analysis, high TIM-3 showed reduced relapse risk (p<0.0001) and longer OS (p=0.0003), together with high PD-1 expression. In multivariate analysis, high TIM-3 was statistically significant in predicting prognosis, showing better DFS (hazard ratio [HR], 0.0994; 95% confidence interval [CI], 0.0296–0.3337; p=0.0002) and longer OS (HR, 0.1109; 95% CI, 0.0314–0.3912; p=0.0006).

Conclusion

In this study, we demonstrate that TIM-3 expression is an independent positive prognostic factor in TNBC, despite its association with poor clinical and pathologic features.

CD147-mediated glucose metabolic regulation contributes to the predictive role of 18 F-FDG PET/CT imaging for EGFR-TKI treatment sensitivity in NSCLC

The aim of this study is to investigate the role of CD147 in glucose metabolic regulation and its association with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) treatment sensitivity prediction using ¹⁸ F-fluorodeoxyglucose (¹⁸ F-FDG) PET/CT imaging in non-small cell lung cancer (NSCLC). In this study, four human NSCLC cell lines with different EGFR-TKI responses were used to detect p-EGFR/EGFR and CD147 expression via Western blotting and flow cytometric analyses. Radioactive uptake of ¹⁸ F-FDG by established stable NSCLC cell lines (HCC827, H1975) with different levels of CD147 expression and the corresponding xenografts was assessed through γ-radioimmunoassays in vitro and micro-PET/CT imaging in vivo to study the role of CD147 in glucose metabolic reprogramming. Correlation analyses were performed to investigate the association between CD147 expression and PD-L1 expression in stable NSCLC cell lines. Higher CD147 expression was found in EGFR-TKI-sensitive NSCLC cell lines than in relatively resistant NSCLC cell lines (HCC827>PC9>A549>H1975). CD147 could promote ¹⁸ F-FDG uptake by HCC827 and H1975 cells in vitro and in vivo through an EGFR-initiated Akt/mTOR-dependent signaling pathway. Programmed cell death-ligand 1 (PD-L1) expression was positively correlated with CD147 expression in human NSCLC cell lines. EGFR-TKI treatment sensitivity prediction in NSCLC using ¹⁸ F-FDG PET/CT imaging significantly correlated with CD147-mediated glucose metabolic regulation via the Akt/mTOR-dependent pathway. Moreover, PD-L1 expression in NSCLC cell lines could be regulated by CD147, suggesting a potential immunosuppression induced by the upregulation of tumor glucose metabolism.

Epidermal growth factor induces STAT1 expression to exacerbate the IFNr-mediated PD-L1 axis in epidermal growth factor receptor-positive cancers

The epidermal growth factor (EGF) receptor (EGFR) overexpressed in many cancers, including lung and head and neck cancers, and is involved in cancer cell progression and survival. PD-L1, increases in tumor cells to evade and inhibit CD8+ T cells, is a clinical immunotherapeutic target. This study investigated the molecular mechanism of EGF on regulating PD-L1 in EGFR-positive cancers and determined potential agents to reduce PD-L1 expression. RNA sequencing (RNAseq) and bioinformatics analysis were performed to determine potential driver genes that regulate PD-L1 in tumor cells-derived tumorspheres which mimicking cancer stem cells. Then, the specific inhibitors targeting EGFR were applied to reduce the expression of PD-L1 in vitro and in vivo. We validated that EGF could induce PD-L1 expression in the selected EGFR-positive cancers. RNAseq results revealed that STAT1 increased as a driver gene in KOSC-3-derived tumorspheres; these data were analyzed using PANTHER followed by NetworkAnalyst. The blockade of EGFR by afatinib resulted in decreased STAT1 and IRF-1 levels, both are transcriptional factors of PD-L1, and disabled the IFNr-STAT1-mediated PD-L1 axis in vitro and in vivo. Moreover, STAT1 knockdown significantly reduced EGF-mediated PD-L1 expression, and ruxolitinib, a JAK1/JAK2 inhibitor, significantly inhibited STAT1 phosphorylation to reduce the IFNr-mediated PD-L1 axis. These results indicate that EGF exacerbates PD-L1 by increasing the protein levels of STAT1 to enforce the IFNr-JAK1/2-mediated signaling axis in selected EGFR-positive cancers. The inhibition of EGFR by afatinib significantly reduced PD-L1 and may be a potential strategy for enhancing immunotherapeutic efficacy.

[Study Progression on Non-small Cell Lung Cancer with EGFR Mutation Treated by Immune Checkpoint Inhibitors]

In recent years, epidermal growth factor receptor tyrosine kinase inhibitors have been recommended by many guidelines as first-line drugs for advanced non-small cell lung cancer (NSCLC) with EGFR gene mutations and no resistance. However, with the prolongation of medication time, most appear acquired resistance. In recent years, breakthroughs in inhibitors of programmed death-1 (PD-1) and its ligand (PD1 ligand, PD-L1) have rapidly changed the therapeutic model of NSCLC. Recent studies have shown that the efficacy of immune checkpoint inhibitors in EGFR-mutant NSCLC patients is not satisfactory, which might be caused by low PD-L1 expression, inhibitory immune microenvironment and low tumor mutation load. This review will elaborate the immune microenvironment of NSCLC patients with EGFR mutation, the latest study progression of immune checkpoint inhibitors and its combined with TKI, expecting to bring new hopes for the treatment of EGFR-mutant NSCLC patients.
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Strong Programmed Death Ligand 1 Expression Predicts Poor Response and De Novo Resistance to EGFR Tyrosine Kinase Inhibitors Among NSCLC Patients With EGFR Mutation

INTRODUCTION

This study evaluated whether tumor expression of programmed death ligand 1 (PD-L1) could predict the response of EGFR-mutated NSCLC to EGFR tyrosine kinase inhibitor (TKI) therapy.

METHODS

We retrospectively evaluated patients who received EGFR-TKIs for advanced NSCLC at the Guangdong Lung Cancer Institute between April 2016 and September 2017 and were not enrolled in clinical studies. The patients' EGFR and PD-L1 statuses were simultaneously evaluated.

RESULTS

Among the 101 eligible patients, strong PD-L1 expression significantly decreased objective response rate, compared with weak or negative PD-L1 expression (35.7% versus 63.2% versus 67.3%, p = 0.002), and shortened progression-free survival (3.8 versus 6.0 versus 9.5 months, p < 0.001), regardless of EGFR mutation type (19del or L858R). Furthermore, positive PD-L1 expression was predominantly observed among patients with de novo resistance rather than acquired resistance to EGFR-TKIs (66.7% versus 30.2%, p = 0.009). Notably, we found a high proportion of PD-L1 and cluster of differentiation 8 (CD8) dual-positive cases among patients with de novo resistance (46.7%, 7 of 15). Finally, one patient with de novo resistance to EGFR-TKIs and PD-L1 and CD8 dual positivity experienced a favorable response to anti-programmed death 1 therapy.

CONCLUSIONS

This study revealed the adverse effects of PD-L1 expression on EGFR-TKI efficacy, especially in NSCLC patients with de novo resistance. The findings indicate the reshaping of an inflamed immune phenotype characterized by PD-L1 and CD8 dual positivity and suggest potential therapeutic sensitivity to programmed death 1 blockade.

Determinants of variability of five programmed death ligand-1 immunohistochemistry assays in non-small cell lung cancer samples

Programmed death ligand-1 (PD-L1) expression as determined by immunohistochemistry (IHC) is potentially predictive of clinical outcome. The aim of this study was to assess the concordance of reported PD-L1 IHC assays and investigate factors influencing variability. Consecutive sections from 20 non-small cell lung cancers (NSCLCs) comprising resection, core biopsy, cytology and pleural fluid samples underwent IHC with 5 different antibody/autostainer combinations: 22C3/Link48, 28-8/BOND-MAX, E1L3N/BOND-MAX, SP142/BenchMark and SP263/BenchMark. PD-L1 RNA levels were assessed using RNAscope. The frequency of positive cases using scoring thresholds from clinical trials was 72%, 33%, 61%, 56%, and 33% for the 5 IHC protocols respectively, and 33% for RNAscope. Pairwise agreement on the classification of cases as positive or negative for PD-L1 expression ranged from 61%-94%. On a continuous scale, the lowest correlation was between 28-8/BOND-MAX and SP142/BenchMark (R²=0.25) and highest was between 22C3/Link48 and E1L3N/BOND-MAX (R²=0.71). When cases were ordered according to tumor cell (TC)%, a similar ranking of cases across IHC protocols could be observed, albeit with different quanta and limits of detection. Single-slide OPAL 7-color fluorescence IHC analysis revealed a high degree of co-localization of staining from the 5 PD-L1 antibodies. Using SP142 antibody in a BOND-MAX protocol led to increased TC% quanta, while retaining a similar ranking of samples according to TC%. The results of this study highlight tumor PD-L1 status can vary significantly according to IHC protocol. Protocol-dependent staining intensities and nominated thresholds for positivity contribute to this variability, while the antibody used appears to be less of a factor.

Immune checkpoint inhibitors in epidermal growth factor receptor mutant non-small cell lung cancer: Current controversies and future directions

Major advances with the development of epidermal growth factor receptor tyrosine kinase inhibitors and immune check-point inhibitors have ushered in a new era in lung cancer therapy. Whilst pre-clinical studies suggest EGFR-driven NSCLC inhibit antitumor immunity through the activation of the PD-1/PD-L1 pathway, epidemiology studies suggest EGFR mutant NSCLC are more likely to have decreased PD-L1 expression. The superiority of single agent PD-1/PD-L1 inhibitors over docetaxel in pre-treated EGFR mutant NSCLC appears to be moderated. Several mechanisms for a poor response to immune checkpoint have been proposed including a lower tumor mutation burden, and an uninflamed and immunosuppressive tumor microenvironment. Predictive biomarkers to PD-1/PD-L1 inhibitors sensitivity in patients with EGFR mutations are required. The role of EGFR TKI in combination with an immune checkpoint inhibitor is currently being investigated intensively in multiple clinical trials and outcomes from these trials are immature and the optimal sequence, schedule and dosing remains to be determined. A careful evaluation will be required in view of the increased toxicities reported in some of the early studies of combination therapy.

Long non-coding RNAs associated with non-small cell lung cancer

Lung cancer, with 80–85% being non-small cell lung cancer (NSCLC), is the leading cause of cancer-related death in both men and women. Long non-coding RNAs (lncRNAs), always defined as non-protein-coding RNA molecules longer than 200 nucleotides, are now thought as a new frontier in the study of human malignant diseases including NSCLC. As researches continue, increasing number of roles that lncRNAs play in NSCLC has been found, and more and more evidences show lncRNAs have a close relationship with patients’ response to radiochemotherapy or molecular therapy. The aim of this review is to disclose the roles that lncRNAs play in NSCLC and how lncRANs influence the treatment of NSCLC.