DNA methylation differences in human p14.5 gene promoter region in normal and proliferating cells

Methylation status of cytosines and its changes during cell proliferation was analyzed in the 5'-flanking region of the human p14.5 gene, which encodes a member of the YER057c/YIL051c/YjgF protein family. We describe evidence of dramatic DNA methylation differences revealed in the study, and present detailed mapping of methylated cytosines (metC) at the 5'-flanking region of the p14.5 gene in several human normal tissues and tumor cells lines. DNA methylation profiles demonstrated aberrant distribution of metC positions with the different degree of methylation along all analyzed 5'-flanking regions of the p14.5 gene in cancer cells. We investigated DNA methylation changes in p14.5 5'-flanking region during cell differentiation by using DNA samples of freshly isolated monocytes and macrophages. According to our data, cellular differentiation processes from monocytes to macrophages are related to the elevated degree of DNA methylation of the p14.5 gene at the putative binding motifs for several transcription factors. The present findings indicate that some cytosines in the promoter region may have some significance in the degree of expression of the p14.5 gene during cell proliferation and cancerogenesis.