Zungsontiporn N.Ngamchokwathana C.Santisukwongchote S.Sitthideatphaiboon P.Leelayuwatanakul N.Korphaisarn K.Chantranuwat P.Sriuranpong V.Aporntewan C.Hirankarn N.Vinayanuwattikun C.Mahidol University2025-10-262025-10-262025-12-01Scientific Reports Vol.15 No.1 (2025)https://repository.li.mahidol.ac.th/handle/123456789/112759The paradoxical impact of T-cell-derived circulating DNA (T-cirDNA) and prognostication in advanced non-small cell lung cancer (NSCLC) has been reported. Further exploration was conducted in 158 EGFR-mutated NSCLC participants who received EGFR inhibitors, correlated with tumor PD-L1 score, CD8 tumor-infiltrating lymphocytes (TILs), and bulk RNA sequencing. We categorized T-cirDNA levels into three groups based on a previous study: undetectable (26.8%), low (≤ 1% ratio; 36.6%), and high (> 1% ratio; 36.6%). Undetectable and high T-cirDNA groups were independent factors correlated with favorable outcomes. The presence of intra-tumoral CD8 TILs (≥ 1%) was also an independent unfavorable prognostic factor; however, it had the lowest proportion in the low T-cirDNA group (16%). Tumor-immune microenvironment (TIME)-related gene set enrichment analysis revealed an overlapped significant heme biosynthesis signature correlated with poor outcome and diverse T-cirDNA group. Despite a high heme biosynthesis signature score in the undetectable T-cirDNA group, inverse correlation with CIBERSORT-activated CD4 memory T-cells was found (R − 0.79, p-value 0.019). Those findings were contrary to the low and high T-cirDNA groups. The significant contribution of heme biosynthesis was the overexpression of CPOX. Crosstalk of EGFR and COPX function prohibits the activation of CD4 + memory T-cells or the spatial intra-tumoral CD8 + T-cells. Undetectable T-cirDNA represents inactivated naïve T-cells and solely active downstream EGFR signaling.MultidisciplinaryArticleSCOPUS10.1038/s41598-025-20307-z2-s2.0-10501910399920452322