(1)v=VmaxSKm+Swherev is the initial rate of malate production (mM/min), [S] is the tumor fumarate concentration (mM), Km is the Km of fumarase for fumarate (mM), and Vmax (mM/min) is the maximal velocity of the enzyme at saturating fumarate concentrations. This evidence concerns the gene FH and neoplasm.