ASMTL (acetylserotonin O-methyltransferase like) is a nucleoside triphosphate pyrophosphatase located on the pseudoautosomal region of sex chrX|Y, representing a unique fusion product of bacterial maf/orfE and ASMT gene sequences 1. The protein hydrolyzes dTTP and UTP, with weak activity toward modified nucleotides, suggesting a dual role in cell division regulation and prevention of modified nucleotide incorporation into cellular nucleic acids 2. However, extensive research has focused on ASMTL-AS1, an antisense long non-coding RNA derived from this locus. ASMTL-AS1 functions as a tumor suppressor across multiple cancer types including gastric cancer, epithelial ovarian cancer, lung adenocarcinoma, papillary thyroid carcinoma, and colorectal cancer 34567. ASMTL-AS1 is characteristically downregulated in malignant tissues and exerts anti-proliferative effects through competing endogenous RNA mechanisms, sponging microRNAs (miR-1270, miR-93-3p, miR-660, miR-1343-3p) to modulate target gene expression 368. In lung adenocarcinoma and renal cell carcinoma, ASMTL-AS1 promotes ferroptosis and inhibits angiogenesis respectively 59. Low ASMTL-AS1 expression correlates with advanced disease stage, poor prognosis, and reduced survival, positioning it as a promising diagnostic and prognostic biomarker for cancer management.