These results implied there were at least two groups of cancer-associated START mutants: one with reduced Caveolin-1 and PLCD1 binding (S912L, L930P, R947C, E966K) and the other in which Caveolin-1 and PLCD1 binding was intact (C1005F, A1017T, and C1036S). This evidence concerns the gene PLCD1 and cancer.