ALCAM and colorectal carcinoma: In support of this postulation, we have demonstrated the presence of CSCs in the colon of humans, as evidenced by the expression of CD44, CD166, and ESA not only in premalignant adenomatous polyps, but also in normal appearing colonic mucosa, where expression of several CSC markers was found to increase with advancing age indicating increased risk in developing CRC with aging 35, 39, 40, 41.