Although clinical studies have shown promise for targeting programmed cell death protein-1 (PD-1) and ligand (PD-L1) signaling in non-small cell lung cancer (NSCLC), the factors that predict which subtype patients will be responsive to checkpoint blockade are not fully understood. We performed an integrated analysis on the multiple-dimensional data types including genomic, transcriptomic, proteomic, and clinical data from cohorts of lung adenocarcinoma public (discovery set) and internal (validation set) database and immunotherapeutic patients. Gene set enrichment analysis (GSEA) was used to determine potentially relevant gene expression signatures between specific subgroups. We observed that mutation significantly increased expression of immune checkpoints and activated T-effector and interferon-γ signature. More importantly, the comutated subgroup manifested exclusive increased expression of PD-L1 and a highest proportion of Meanwhile, or -mutated tumors showed prominently increased mutation burden and specifically enriched in the transversion-high (TH) cohort. Further analysis focused on the potential molecular mechanism revealed that or mutation altered a group of genes involved in cell-cycle regulating, DNA replication and damage repair. Finally, immunotherapeutic analysis from public clinical trial and prospective observation in our center were further confirmed that or mutation patients, especially those with co-occurring mutations, showed remarkable clinical benefit to PD-1 inhibitors. This work provides evidence that and mutation in lung adenocarcinoma may be served as a pair of potential predictive factors in guiding anti-PD-1/PD-L1 immunotherapy. .

Patients with mutations showed unfavorable response to programmed cell death-1 (PD-1) blockade immunotherapy in non-small cell lung cancer (NSCLC). Yet the underlying association between mutation and immune resistance remains largely unclear. We performed an integrated analysis of PD-ligand 1(PD-L1)/CD8 expression and mutation profile based on the repository database and resected early-stage NSCLC in Guangdong Lung Cancer Institute (GLCI). Meanwhile, 2 pool-analyses were set to clarify the correlation between mutation and PD-L1 expression, and the association of status with response to anti-PD-1/L1 therapy. Pool-analysis of 15 public studies suggested that patients with mutations had decreased PD-L1 expression (odds ratio: 1.79, 95% CI: 1.10-2.93; P = 0.02). Analysis of The Cancer Genome Atlas (TCGA) and the GCLI cohort confirmed the inverse correlation between mutation and PD-L1 expression. Furthermore, patients with mutation showed a lack of T-cell infiltration and shrinking proportion of PD-L1/CD8 TIL (P = 0.034). Importantly, patients with mutations, especially the sensitive subtype, showed a significantly decreased mutation burden, based on analysis of the discovery and validation sets. Finally, a pool-analysis of 4 randomized control trials confirmed that patients with mutation did not benefit from PD-1/L1 inhibitors (Hazard ratio [HR] = 1.09, P = 0.51) while patients with wild-type did (HR = 0.73, P< 0.00001). This study provided evidence of a correlation between mutations and an uninflamed tumor microenvironment with immunological tolerance and weak immunogenicity, which caused an inferior response to PD-1 blockade in NSCLCs.

BackgroundThe anaplastic lymphoma kinase (ALK) gene is frequently involved in translocations that lead to gene fusions in a variety of human malignancies, including lymphoma and lung cancer. Fusion partners of ALK include NPM, EML4, TPM3, ATIC, TFG, CARS, and CLTC. Characterization of ALK fusion patterns and their resulting clinicopathological profiles could be of great benefit in better understanding the biology of lung cancer.ResultsRACE-coupled PCR sequencing was used to assess ALK fusions in a cohort of 103 non-small cell lung carcinoma (NSCLC) patients. Within this cohort, the EML4-ALK fusion gene was identified in 12 tumors (11.6%). Further analysis revealed that EML4-ALK was present at a frequency of 16.13% (10/62) in patients with adenocarcinomas, 19.23% (10/52) in never-smokers, and 42.80% (9/21) in patients with adenocarcinomas lacking EGFR and KRAS mutations. The EML4-ALK fusion was associated with non-smokers (P = 0.03), younger age of onset (P = 0.03), and adenocarcinomas without EGFR/KRAS mutations (P = 0.04). A trend towards improved survival was observed for patients with the EML4-ALK fusion, although it was not statistically significant (P = 0.20). Concurrent deletion in EGFR exon 19 and fusion of EML4-ALK was identified for the first time in a Chinese female patient with an adenocarcinoma. Analysis of ALK expression revealed that ALK mRNA levels were higher in tumors positive for the EML-ALK fusion than in negative tumors (normalized intensity of 21.99 vs. 0.45, respectively; P = 0.0018). However, expression of EML4 did not differ between the groups.ConclusionsThe EML4-ALK fusion gene was present at a high frequency in Chinese NSCLC patients, particularly in those with adenocarcinomas lacking EGFR/KRAS mutations. The EML4-ALK fusion appears to be tightly associated with ALK mRNA expression levels. RACE-coupled PCR sequencing is a highly sensitive method that could be used clinically for the identification of EML4-ALK-positive patients.