Figure 2
Metformin blocks cell cycle progression at the G0/G1 phase. Human OSCC cells (CAL27, WSU-HN6, and SCC25) were grown in 6-well plates (2 × 105 cells/well). After 24 h, the culture medium was removed and replaced with fresh culture medium containing 0 mM or 20 mM metformin for an additional 24 h. (A) Cell cycle progression in OSCC cells was assessed by flow cytometry. (B) The expression of related cell-cycle regulatory proteins in arrested and proliferating OSCC cells treated with or without metformin was assessed by immunoblotting. One representative experiment out of three is shown.