DNA Methylation of the hTERT Gene in Breast Cancer Revisited: Diagnostic and Clinical Implications.

Background: It is documented that in tumor cell lines, the hTERT gene exhibits prominent methylation at a CpG island rich region about -600 bp upstream of the transcription start site, but mixed or allelically absent around ±150 bp region. Given the potential clinical implications of the findings in breast cancer diagnostics, we set out to investigate if such findings are reproducible on primary surgically resected invasive breast carcinomas.

Methods: The cohort consisted of 50 cases of freshly sampled and formalin-fixed paraffin embedded (FFPE) invasive breast cancers and normal tissue.