APOC3 and Hypercholesterolemia: As predicted from the microarray data, hypercholesterolemia reduced the mRNA levels of ATF3 as well as ID1, and enhanced those of C3 (apolipoprotein C3), S100A (S100 calcium-binding protein A) and IFI44 (gamma-interferon-inducible protein 44) (Fig. 3B).