In vitro quantification of the cytotoxic T lymphocyte response against human telomerase reverse transcriptase in breast cancer.

Telomerase is expressed in approximately 90% of breast cancers but not in normal somatic cells. The catalytic subunit of telomerase, human telomerase reverse transcriptase (hTERT), is a widely expressed tumour-associated antigen against which specific cytotoxic T lymphocyte (CTL) responses have been identified. Human CD8+ CTL have been shown to recognise hTERT synthetic peptides in an HLA-restricted manner and to lyse hTERT+ tumour cells.