The association of genomic alterations with PD-L1 expression in Chinese patients with EGFR/ALK wild-type lung adenocarcinoma and potential predictive value of Hippo pathway mutations to immunotherapy.

The study focuses on PD-L1 expression as an essential biomarker for gauging the response of EGFR/ALK wild-type NSCLC patients to FDA-approved immune checkpoint inhibitors (ICIs). It aims to explore clinical, molecular, and immune microenvironment characteristics associated with PD-L1 expression in EGFR/ALK wild-type lung adenocarcinoma patients eligible for ICI therapy. In this retrospective study, tumor samples from 359 Chinese EGFR/ALK wild-type lung adenocarcinoma patients underwent comprehensive evaluations for PD-L1 expression and NGS-targeted sequencing. The investigation encompassed the analysis and comparison of clinical traits, gene mutations, pathways, and immune signatures between two groups categorized by PD-L1 status: negative (TPS < 1%) and positive (TPS ≥ 1%). Additionally, the study explored the link between genomic changes and outcomes following immunotherapy. High tumor mutational burden correlated significantly with PD-L1 positivity in patients with EGFR/ALK wild-type lung adenocarcinoma. Gene alterations, including TP53, KRAS, and others, were more pronounced in the PD-L1 positive group. Pathway analysis highlighted higher frequencies of alterations in pathways like RTK/RAS, p53, and Hippo in PD-L1-positive patients. The Hippo pathway's relevance was confirmed in separate immunotherapy cohorts, associated with better outcomes. In terms of immune cell infiltration, Hippo mutants exhibited higher levels of CD68+ PD-L1+ macrophages, CD8+ T cells, and CD8+ PD-1- T cells. This study offers insights into genomic features of Chinese EGFR/ALK wild-type lung adenocarcinoma patients based on PD-L1 expression. Notably, Hippo pathway alterations were linked to improved immunotherapy outcomes. These findings suggest connections between the Hippo pathway and PD-L1 expression, warranting further clinical and functional investigations. The research advances our understanding of PD-L1 expression's genomic context and immunotherapy response in EGFR/ALK wild-type lung adenocarcinoma.

Liu F ，Zhang X ，Lu M ，Liu C ，Zhang X ，Chu Q ，Chen Y ，Zhang P ... -  《Cancer Medicine》

Integration of comprehensive genomic profiling, tumor mutational burden, and PD-L1 expression to identify novel biomarkers of immunotherapy in non-small cell lung cancer.

This study aimed to explore the novel biomarkers for immune checkpoint inhibitor (ICI) responses in non-small cell lung cancer (NSCLC) by integrating genomic profiling, tumor mutational burden (TMB), and expression of programmed death receptor 1 ligand (PD-L1). Tumor and blood samples from 637 Chinese patients with NSCLC were collected for targeted panel sequencing. Genomic alterations, including single nucleotide variations, insertions/deletions, copy number variations, and gene rearrangements, were assessed and TMB was computed. TMB-high (TMB-H) was defined as ≥10 mutations/Mb. PD-L1 positivity was defined as ≥1% tumor cells with membranous staining. Genomic data and ICI outcomes of 240 patients with NSCLC were derived from cBioPortal. EGFR-sensitizing mutations, ALK, RET, and ROS1 rearrangements were associated with lower TMB and PD-L1+/TMB-H proportions, whereas KRAS, ALK, RET, and ROS1 substitutions/indels correlated with higher TMB and PD-L1+/TMB-H proportions than wild-type genotypes. Histone-lysine N-methyltransferase 2 (KMT2) family members (KMT2A, KMT2C, and KMT2D) were frequently mutated in NSCLC tumors, and these mutations were associated with higher TMB and PD-L1 expression, as well as higher PD-L1+/TMB-H proportions. Specifically, patients with KMT2C mutations had higher TMB and PD-L1+/TMB-H proportions than wild-type patients. The median progression-free survival (PFS) was 5.47 months (95% CI 2.5-NA) in patients with KMT2C mutations versus 3.17 months (95% CI 2.6-4.27) in wild-type patients (p = 0.058). Furthermore, in patients with NSCLC who underwent ICI treatment, patients with TP53/KMT2C co-mutations had significantly longer PFS and greater durable clinical benefit (HR: 0.48, 95% CI: 0.24-0.94, p = 0.033). TP53 mutation combined with KMT2C or KRAS mutation was a better biomarker with expanded population benefit from ICIs therapy and increased the predictive power (HR: 0.46, 95% CI: 0.26-0.81, p = 0.007). We found that tumors with different alterations in actionable target genes had variable expression of PD-L1 and TMB in NSCLC. TP53/KMT2C co-mutation might serve as a predictive biomarker for ICI responses in NSCLC. Cancer immunotherapies, especially immune checkpoint inhibitors (ICIs), have revolutionized the treatment of non-small cell lung cancer (NSCLC); however, only a proportion of patients derive durable responses to this treatment. Biomarkers with greater accuracy are highly needed. In total, 637 Chinese patients with NSCLC were analyzed using next-generation sequencing and IHC to characterize the unique features of genomic alterations and TMB and PD-L1 expression. Our study demonstrated that KMT2C/TP53 co-mutation might be an accurate, cost-effective, and reliable biomarker to predict responses to PD-1 blockade therapy in NSCLC patients and that adding KRAS to the biomarker combination creates a more robust parameter to identify the best responders to ICI therapy.

Shi Y ，Lei Y ，Liu L ，Zhang S ，Wang W ，Zhao J ，Zhao S ，Dong X ，Yao M ，Wang K ，Zhou Q ... -  《Cancer Medicine》

Molecular heterogeneity of anti-PD-1/PD-L1 immunotherapy efficacy is correlated with tumor immune microenvironment in East Asian patients with non-small cell lung cancer.

Objective: The aim of this study was to investigate how the tumor immune microenvironment differs regarding tumor genomics, as well as its impact on prognoses and responses to immunotherapy in East Asian patients with non-small cell lung cancer (NSCLC). Methods: We performed an integrated analysis using publicly available data to identify associations between anti-programmed death 1 (PD-1)/ programmed death-ligand 1 (PD-L1) immunotherapy efficacy and classic driver oncogene mutations in East Asian NSCLC patients. Four pooled and clinical cohort analyses were used to correlate driver oncogene mutation status and tumor microenvironment based on PD-L1 and CD8+ tumor-infiltrating lymphocytes (TILs). Immune infiltrating patterns were also established for genomic NSCLC subgroups using the CIBERSORT algorithm. Results: Based on East Asian NSCLC patients, TIDE analyses revealed that for anti-PD-1/PD-L1 immunotherapy, epidermal growth factor receptor (EGFR)-mutant and anaplastic lymphoma kinase (ALK)-rearranged tumors yielded inferior responses; however, although Kirsten rat sarcoma viral oncogene homolog (KRAS)-mutant tumors responded better, the difference was not statistically significant (EGFR: P = 0.037; ALK: P < 0.001; KRAS: P = 0.701). Pooled and clinical cohort analyses demonstrated tumor immune microenvironment heterogeneities correlated with oncogenic patterns. The results showed remarkably higher PD-L1- and TIL-positive KRAS-mutant tumors, suggesting KRAS mutations may drive an inflammatory phenotype with adaptive immune resistance. However, the EGFR-mutant or ALK-rearranged groups showed a remarkably higher proportion of PD-L1-/TIL-tumors, suggesting an uninflamed phenotype with immunological ignorance. Notably, similar to triple wild-type NSCLC tumors, EGFR L858R-mutant tumors positively correlated with an inflammatory phenotype, suggesting responsiveness to anti-PD-1/PD-L1 immunotherapy (P < 0.05). Furthermore, the CIBERSORT algorithm results revealed that EGFR-mutant and ALK-rearranged tumors were characterized by an enriched resting memory CD4+ T cell population (P < 0.001), as well as a lack of CD8+ T cells (P < 0.01), and activated memory CD4+ T cells (P = 0.001). Conclusions: Our study highlighted the complex relationships between immune heterogeneity and immunotherapeutic responses in East Asian NSCLC patients regarding oncogenic dependence.

Jin R ，Liu C ，Zheng S ，Wang X ，Feng X ，Li H ，Sun N ，He J ... -  《Cancer Biology & Medicine》

Impact of cytotoxic chemotherapy on PD-L1 expression in patients with non-small cell lung cancer negative for EGFR mutation and ALK fusion.

Immune-checkpoint inhibitors (ICIs) are now an established therapeutic option for advanced non-small cell lung cancer (NSCLC). It has remained unclear, however, whether cytotoxic chemotherapy affects the immune microenvironment in NSCLC wild type for EGFR and ALK. We retrospectively evaluated changes in programmed cell death 1-ligand 1 (PD-L1) expression, tumor mutation burden (TMB), and CD8+ tumor-infiltrating lymphocyte (TIL) density in NSCLC patients who underwent rebiopsy at the site of recurrence after postoperative platinum-based adjuvant chemotherapy, or in those who underwent rebiopsy after one or more chemotherapeutic regimens at the advanced stage. The PD-L1 tumor proportion score (TPS) and CD8+ TIL density were determined by immunohistochemistry. TMB was estimated by next-generation sequencing with a cancer gene panel (409 genes). Seventeen patients with NSCLC wild type for EGFR and ALK were enrolled. Although PD-L1 TPS tended to be increased in rebiopsy samples compared with initial biopsy tissue, this difference was not significant (P =  0.113). Seven patients showed an increase in PD-L1 TPS, with this change being pronounced in four. Two cases in which PD-L1 TPS increased from 0 to 90% or from 0 to 95% after cytotoxic chemotherapy also showed a durable response to subsequent treatment with an ICI. No substantial correlation between PD-L1 TPS and TMB was apparent either before (R = 0.112) or after (R = 0.101) chemotherapy. A moderate correlation was detected between PD-L1 TPS and CD8+ TIL density before chemotherapy (R = 0.517) and a negligible correlation after (R = 0.0219). Cytotoxic chemotherapy may change the biological characteristics of tumors including PD-L1 expression level and TMB.

Sakai H ，Takeda M ，Sakai K ，Nakamura Y ，Ito A ，Hayashi H ，Tanaka K ，Nishio K ，Nakagawa K ... -  《-》

Clinical relevance of PD-L1 expression and CD8+ T cells infiltration in patients with EGFR-mutated and ALK-rearranged lung cancer.

EGFR-mutated or ALK-rearranged non-small cell lung cancer (NSCLC) often showed unfavorable clinical benefit to checkpoint inhibitors (CPIs). However, few reports exist with integrated analysis, to interpret the underlying mechanism of poor response to PD-1/PD-L1 inhibitors. We have retrospectively analyzed the tumor microenvironment (TME) based on tumor PD-L1 expression and CD8+ T cells infiltration in patients with EGFR mutations and ALK rearrangements, and the prognostic value of TME subtypes on overall survival (OS). Tumor samples from 715 patients with lung cancer were retrospectively collected at Guangdong Lung Cancer Institute. Tumoral PD-L1 expression (N = 715) and CD8+ T cells infiltration (N = 658) was determined by immunohistochemistry (IHC), based on which TME was categorized into four different subtypes: PD-L1+/CD8+, PD-L1-/CD8+, PD-L1+/CD8-, PD-L1-/CD8-. Proportion of four TME subtypes was determined, and overall survival with PD-L1 expression and TME was analyzed. In patients with EGFR mutations or ALK rearrangements, proportion of PD-L1+/CD8+ tumors was the lowest (5.0%, 17/342), and that of PD-L1-/CD8- tumors was the highest (63.5%, 217/342). In patients with wild-type EGFR and ALK, 14.2% (45/316) tumors were PD-L1+/CD8+ and 50.3% (159/316) tumors were PD-L1-/CD8- (P < 0.001). Median OS of EGFR-mutated or ALK-rearranged lung cancer was 78.6 months in PD-L1 positive group and 93.4 months in PD-L1 negative group (HR 0.47, 95%CI 0.23-0.76, P = 0.005). PD-L1+/CD8+ group exhibited the shortest OS, with 44.3 months, but is likely to respond to CPIs. The PD-L1-/CD8+ group exhibited the longest OS but is unlikely to respond to CPIs. Patients with EGFR mutations or ALK rearrangements exhibited lower PD-L1 and CD8 co-expression level in TME, which could be responsible for poor response to CPIs. PD-L1 and CD8 co-expression in EGFR-mutated or ALK-rearranged lung cancer is a biomarker for poor prognosis with shorter OS.

Liu SY ，Dong ZY ，Wu SP ，Xie Z ，Yan LX ，Li YF ，Yan HH ，Su J ，Yang JJ ，Zhou Q ，Zhong WZ ，Tu HY ，Yang XN ，Zhang XC ，Wu YL ... -  《-》