In contrast, dietary CLA administration has also been shown to lead to tumor progression and cellular expansion mediated through increased phosphorylation of the insulin-like growth factor 1 (IGF-I)/insulin receptor, as well as through increased signaling of the mitogen-activated protein kinase/ERK kinase (MEK)/extracellular-signal-regulated kinase (ERK) (MEK-ERK) and phosphoinositide 3-kinases–protein kinase B (PI3K-AKT) pathways in tumor cells [80,81,82]. Here, IGF1 is linked to neoplasm.