Abstract
Purpose:
Metformin is an anti-diabetic drug with anti-gluconeogenesis and insulin sensitizing properties used for the treatment of type 2 diabetes. Recent studies suggest that metformin may reduce the risk of cancer, but its mode of action remains uncertain. In this study we examined the effect of metformin on human retinoblastoma cell proliferation in vitro.
Methods:
Two different human retinoblastoma cell lines (Y79, WERI) were treated with metformin (0.6-10mM) for 1, 3 and 5 days. Cell proliferation and growth inhibition were assessed by MTT assay, trypan blue exclusion and viability/cytotoxicity calcein AM/ethidium homodimer test. Mitochondrial function was tested with Mitotracker and ATP generation assays.
Results:
Metformin inhibited retinoblastoma growth and proliferation in a dose dependent manner. Treatment with metformin resulted in increased doubling time of retinoblastoma cells and significant impairment of the redox state of the cells leading to an overestimation of doubling time measured by the MTT assay.
Conclusions:
Metformin is a potent inhibitor of growth and proliferation of retinoblastoma cell lines. It has a potential to be used as non-chemotherapeutic adjuvant drug for retinoblastoma.
Keywords: 744 tumors •
449 cell survival