SPAG6 and hepatocellular carcinoma: In a subgroup analysis, we examined the differences between viral and non-viral related etiologies and observed significantly increased DNA methylation levels of SPAG6 and NKX2-4 in viral-related (HBV + HCV) cirrhotic HCC compared to non-viral-related (MASLD + ALD) cirrhotic HCC (Supplementary Fig. 1).