Epitalon increases telomere length in human cell lines through telomerase upregulation or ALT activity

Al-Dulaimi S, Thomas R, Matta S, Roberts T · Biogerontology

Telomere length rose in all four lines. In the two normal lines nothing changed at four days and the rise appeared only after three weeks, with hTERT mRNA up and telomerase activity up fourfold in IBR.3 and 26-fold in HMEC. In the two cancer lines hTERT mRNA rose 12-fold and fivefold but telomerase activity did not change, and their telomeres lengthened through the alternative-lengthening (ALT) pathway instead: C-circle ALT activity up tenfold in 21NT and threefold in BT474, with PML bodies increased. ALT was not activated in the normal lines. At the lowest dose, 0.1 µg/ml, telomere length fell in 21NT.

Population

Two human breast-cancer lines (21NT and BT474) and two normal human lines, IBR.3 fibroblasts and HMEC mammary epithelial cells

Intervention

Epitalon 0.1 to 1 µg/ml daily for 4 days in the cancer lines, and 1 µg/ml daily for 3 weeks in the normal lines; the peptide was bought from an online peptide vendor

Comparator

Untreated cultures

Limitations

Two-dimensional cell culture; qPCR reports an average telomere length across all chromosomes. A November 2025 correction replaced figures 1 to 3 with corrected versions and left the text unchanged. Funded by the authors' own department and by self-funding students, no competing interests. The conclusion that the peptide can be safely used in healthy individuals rests on the absence of ALT activation in two normal lines; the cancer-line finding is the first report of the peptide lengthening telomeres in cancer cells and points the other way. The first reproduction of the 2003 institute result by a laboratory with no institute author.