The proportionality of glutaminase content to growth rate and morphology of rat neoplasms.

Correlations were demonstrated among the growth rates, concentrations of kidney-type of phosphate-dependent gluta minase, and morphologies of seven types of transplanted and primary rat neoplasms. The exponential rates of growth in volume of each of the transplanted rat neoplasms were respec tively similar to their rates of cellular growth, measured with colchicine. The relative degrees of histologic differentiation were quantified by a ranking procedure. The concentrations of enzyme present in the tumors were proportional to the rates of growth over the 5-fold ranges encompassed by this material, and the faster growing tumors with more enzyme were propor tionately more undifferentiated. The glutaminase apparently plays a significant role in neoplastic type of metabolism in this series of heterogeneous tumors because it is quantitatively pro portional to the two main biologic properties of these neo plasms.