METTL1 and neoplasm: METTL1 was specifically selected for further investigation based on the following rationale: (1) it showed a strong and consistent positive correlation with TXNDC12 expression in several publicly available HNSCC cohorts; (2) this correlation was also observed in other tumor types, suggesting a broader regulatory association; and (3) METTL1 encodes an RNA methyltransferase known to influence mRNA stability and translation through epitranscriptomic mechanisms, which may functionally impact TXNDC12 expression at the post-transcriptional level.