Hopf bifurcation of tumor growth under direct effect of inhibitors with two time delays

Abstract

In this paper, a mathematical model for growth of tumors with two discrete delays is studied. The delays respectively represents the time taken for cells to undergo mitosis and the time taken for the cell to modify the rate of cell loss due to apoptosis and kill of cells by the inhibitor. We show the in°uence of time delays on the Hopf bifurcation when one of delays is used as a bifurcation parameter.