IL4 and colorectal carcinoma: PI3K-AKT pathway, JAK-STAT pathway and MAPK pathway can potentially be the downstream of IL4/IL4R signal (Heredia et al. 2013; Keijzer et al. 2011; Malabarba et al. 1995; Friedrich and Wietek 2001), we revealed that the blockage of ERK pathway most significantly inhibited the IL-4-mediated proliferation of early OCPs, while AKT pathway also partially regulated the proliferation, indicating IL-4 regulated the proliferation of early OCPs during bone metastasis of CRC through several ways and ERK pathway could be the most important regulator.