Comprehensive analysis of PD-L1 expression, tumor-infiltrating lymphocytes, and tumor microenvironment in LUAD: differences between Asians and Caucasians

Abstract

Backgrounds The characteristics of programmed cell death protein-1 (PD-L1) expression, tumor-infiltrating lymphocytes (TILs), and tumor microenvironment (TME) in lung adenocarcinoma (LUAD) patients are closely related to immunotherapy, and there are differences between Asians and Caucasians. Methods Acquire the transcriptome data of the Cancer Genome Atlas and Chinese LUAD patients. R software was used to analyze the differential expression of genes, prognosis, and gene function. Use CIBERSORT for TIL-related analysis and ESTIMATE for TME-related analysis. Results The expression of PD-L1 in tumor tissues of Caucasian LUAD patients was lower than that in normal tissues, while there was no significant difference in Asians. There was no statistical difference between PD-L1 expression and prognosis. The composition of TILs between Caucasian and Asian LUAD patients was quite different. There was no correlation between TILs and prognosis in Caucasians. However, the higher content of resting mast cells indicated a better prognosis in Asians. The Caucasian patients with higher immune and estimate scores had a better prognosis (p = 0.021, p = 0.025). However, the Asian patients with a higher estimate score had a worse prognosis (p = 0.024). The high expression of COL5A2 (p = 0.046, p = 0.027) and NOX4 (p = 0.020, p = 0.019) were both associated with the poor prognosis in Caucasians and Asians. Conclusion There are many differences in the characteristics of PD-L1 expression, TILs, and TME between Caucasian and Asian LUAD patients. This provides a certain hint for the selection of specific immunotherapy strategies separately for Caucasian and Asian LUAD patients.

Identification and experimental verification of an anoikis and immune related signature in prognosis for lung adenocarcinoma

“…Five-year survival rates for LUAD patients have been improved significantly due to the rapid development of immunotherapy ( 43 ). However, the degree of response to immunotherapy varies from patient to patient due to individual heterogeneity ( 44 , 45 ). Different levels of immune cell infiltration and TMB often lead to contrary clinical outcomes compared to expectations ( 46 , 47 ).…”

Differentially Infiltrated Identification of Novel Diagnostic Biomarkers Associated with Immune Infiltration in Nasopharyngeal Carcinoma

“…Meanwhile, the number of NK cells combined with mast cells can be used as a biomarker to predict the recurrence or distant metastasis of NPC [ 20 ]. Although Asians have a high content of resting mast cells and a good prognosis in lung adenocarcinoma [ 30 ], there are few studies on nasopharyngeal carcinoma. In this study, NK cells were activated, M0 macrophages, M1 macrophages, dendritic cells rested, and activated mast cells and neutrophils infiltrated in NPC.…”

Characterization of lung adenocarcinoma based on immunophenotyping and constructing an immune scoring model to predict prognosis

“…Recently, immunotherapy has also been developed as a new treatment for LUAD ( Saito et al, 2018 ). Moreover, antibodies against PD-1 and PD-L1 have been reported to be effective in the treatment of various malignancies ( Antonia et al, 2017 ; Bie et al, 2021 ). Although the biology of the TIME driving these responses was not fully understood, it is critical for the design of immunotherapeutic strategies.…”