SPINK4 and malignant colon neoplasm: Although none of the top 20 co-expressed genes outperformed L1TD1 as independent prognostic marker for colon cancer in all the three data sets, five genes had statistically significant (P < 0.05) impact on survival in at least two out of the three colon cancer data sets (Table 4): Serine peptidase inhibitor Kazal type 4 (SPINK4), Resistin-like beta (RETNLB), Asparaginase-like 1 Protein (ASRGL1), Chloride channel accessory 1 (CLCA1), and Fc fragment of IgG binding protein (FCGBP) (Additional file 1: Figure S6).