SERPINA1 and colorectal adenocarcinoma: SERPINA1 is a serine protease inhibitor belonging to the serpin surperfamily, elevated level of which is related to the invasive potential of gastric, lung and colorectal adenocarcinoma,41, 42, 43 On the contrary, other studies have proved that SERPINA1 is significantly downregulated in a variety of cancers, and patients with high expression of SERPINA1 have a longer overall survival than patients with low expression, showing an anti‐cancer effect.44, 45, 46