Genomic analysis and biomarker discovery of thymic cancer based on whole exome sequencing: A retrospective cohort study / 中国胸心血管外科临床杂志

ABSTRACT

@#Objective To examined gene mutations in thymic carcinoma (TC) patients and to explore prognostic correlates and potential targets for therapy. Methods We retrospectively included TC patients in Sichuan Cancer Hospital between January 2015 and Febuary 2021.Whole-exome sequencing was performed on tumor tissues from TC patients and their control peripheral blood samples, and the raw data were subjected to bioinformatics analysis and statistical analysis. Results We finally included 24 TC patients with 16 males and 8 females at a median age of 55 (42-74) years. The highest frequency of single nucleotide mutations in this cohort were in the TTN gene (42%), HSPG2 (29%), and OBSCN (29%). Higher frequency of copy number variations occurred in ZNF276 gene (54%, loss), BEND3 (50%, loss), DHODH (50%, loss), and VAC14 (50%, loss). Microsatellite instability (MSI) phenotype was found in 25% of the patients, and the mean tumor mutation burden (TMB) was 9.86. Conclusion This study is the first comprehensive analysis of the mutation profile of thymic carcinoma in China to date. The mutation frequencies of TTN, OBSCN, and ZNF276 genes were high. The biomarker analysis suggests that patients may benefit from immunotherapy and have a long effective survival.