Cell proliferation in normal and malignant transformed cells: Thermodynamic model of signal transduction

We present a new thermodynamic model for the mechanism of activation and re gulation of cell proliferation in the G(1) stage. In this model, the intera ctions between growth factors and transmembrane proteins play a crucial rol e in cell growth control for a normal tissue-culture system. We calculate a phase diagram of normal and malignant transformed states of a cell signal transduction system. We propose thermodynamic reasons why cancer cells can continually grow without activation by the growth factors.