STK11 and colorectal carcinoma: As compared to the FHC colon epithelial cells (“Epi”) [28], PKCζ mRNA (Figure 1D) and protein (Figure 1E) expressions were both elevated in the human CRC cells (HT-29 and DLD-1), yet AMPK activation, reflected by p-LKB1 (Ser-428) and p-AMPKα1, was low (Figure 1E).