Synergistic effects of hydroxyurea and thymidine on the growth inhibition of V79 cells.

The effects of hydroxyurea (HU) and thymidine (TdR) on cell cycle progression in V79 Chinese hamster lung cells were examined by flow cytometry. Suppression of the cell cycle progress rate by HU was further enhanced by the combination of a low concentration of TdR and HU as compared to that induced by TdR alone; i.e., these drugs were shown to have a synergistic effect. It was concluded that the presence of TdR was effective in assisting HU-induced suppression of DNA synthesis.