APOA2 and neoplasm: By using Principal Component Analysis (PCA), in combination with uni- and multivariable linear regression analyses, total plasma apolipoprotein-A1 and the contents of cholesterol, free cholesterol, apolipoprotein-A1, apolipoprotein-A2, and phospholipids of HDL, HDL-1, HDL-2 and HDL-3, were associated with tumor PgR expression (Table 3).