Atherosclerosis (AS) is the leading cause of cardiovascular diseases (CVDs) with a high rate of mortality worldwide. Plasma cell-free DNA (cfDNA), mainly originating from apoptosis, necrosis, and active secretion, has been recognized as a promising biomarker for the diagnosis and prognosis of multiple cancers, whereas there are no reports about cfDNA in CVDs. Here, we found an increased quantity and decreased integrity of cfDNA (cfDI) in the serum from AS patients compared with normal controls. Moreover, the reduced cfDI is inversely correlated with serum LDL levels, carotid plaque size, and carotid plaque thickness in the progression of AS. Consistently, in vivo experiments confirmed that the release and cleavage of cfDNA were increased concomitantly with the development and progression of AS in ApoE⁻/⁻ mice. Our study sheds light on the potential of cfDNA and cfDI as molecular biomarkers for detecting and monitoring AS.

N¹-Methyladenosine (m¹A) is a prevalent RNA modification that governs RNA metabolism, structure, stability, and translation. Yet its cancer-wide landscape and functional impact remain largely unexplored. Here, we delineate the m¹A regulatory network in lung squamous cell carcinoma (LUSC). The dominant m¹A writer of TRMT6 emerged as the most up-regulated regulator in LUSC through a comprehensive pan-cancer analysis; both TRMT6 expression and global m¹A levels significantly distinguished LUSC from normal tissue, serving as potent diagnostic biomarkers. Functionally, TRMT6 installs m¹A marks and facilitates their cellular export. Both the in vitro and in vivo experiments reveal that TRMT6 accelerates LUSC proliferation by orchestrating cell-cycle gene expression. Mechanistically, TRMT6 binds cell-cycle transcripts, most notably TOPBP1 and DSN1, promotes the formation of m¹A, and stabilizes these mRNAs via the YTHDF3 reader pathway. A single, critical m¹A site in each target mRNA is sufficient to boost TOPBP1 and DSN1 expression. Using dCasRx-TRMT6, we further show that site-specific m¹A deposition on DSN1 mRNA is a potent strategy to modulate its expression and drive proliferation. Collectively, our findings uncover a previously unrecognized m¹A-dependent regulatory axis that underpins LUSC diagnosis and progression.