<b>Methods:</b> We analyzed CpG methylation within promoter-associated CpG islands of the PTase genes <i>FNTA</i>, <i>FNTB</i>, <i>PGGT1B</i>, and <i>RABGGTA</i> via bisulfite conversion and pyrosequencing to assess its role in PTase expression and gain deeper insight into the regulation of protein prenylation in cancer. Here, PGGT1B is linked to cancer.