Methylation of the p16Ink4a tumor suppressor gene 5′-CpG island in breast cancer

N. H. Nielsen, G. Roos, S. O. Emdin, G. Landberg

    Research output: Contribution to journalArticlepeer-review


    Methylation of the p16Ink4a tumor suppressor gene 5′CpG island was analyzed in 104 primary breast cancer specimens using Southern blotting and methylation specific polymerase chain reaction (PCR) (MSP). Eight and four tumors, respectively, showed methylation, and all MSP positive tumors were detected by Southern blotting. To investigate possible methylation not detectable by these methods, bisulphite genomic sequencing was performed in 220 clones from 14 selected tumors. Absent methylation or methylation of single CpG dinucleotides prevailed in all tumors, but of the MSP positive tumors, three contained alleles with methylation of 31 or 32 of the 32 analyzed CpG dinucleotides in the island. Partially methylated alleles were also observed. In a group with low p16Ink4a expression determined by Western blotting, four randomly selected tumors contained several identical clones with methylation of 15 CpG dinucleotides by bisulphite genomic sequencing but with a methylation pattern that did not support detection by either Southern blotting or MSP, increasing the potential significance of p16Ink4a methylation in breast cancer. © 2001 Elsevier Science Ireland Ltd.
    Original languageEnglish
    Pages (from-to)59-69
    Number of pages10
    JournalCancer Letters
    Issue number1
    Publication statusPublished - 10 Feb 2001


    • 5′-CpG methylation
    • Breast cancer
    • Cell cycle
    • p16Ink4a


    Dive into the research topics of 'Methylation of the p16Ink4a tumor suppressor gene 5′-CpG island in breast cancer'. Together they form a unique fingerprint.

    Cite this