This study aims to analyze the tumor microenvironment characteristics of patients with brain metastasis of lung adenocarcinoma and explore the expression of PPP1R13L in brain metastasis tissues and its clinical significance by single-cell sequencing and clinical sample analysis.<h4>Methods</h4>Brain tissues from 4 patients with lung adenocarcinoma brain metastasis and 2 patients with oligodendroglioma (ODG) were collected from the Affiliated Tumor Hospital of Xinjiang Medical University from January 2014 to December 2024 for single-cell sequencing. The gene discussed is PPP1R13L; the disease is lung adenocarcinoma.