MYC and malignant colon neoplasm: In three human leukemic cell lines (HL-60, U937, and ML-1) [313] and in colon cancer cells (Caco-2 and HT-29) [314], telomerase activity and hTERT expression were downregulated by 4-HNE, as a consequence of downregulation of c-myc mRNA expression and c-Myc DNA binding activity as well as upregulation of mad-1 mRNA expression and Mad-1 DNA binding activity.