In 2013, Alkhateeb et al. observed decreased ferritin expression in breast cancer cells but increased infiltration of ferritin-rich CD68-positive macrophages with increased tumour histological grade, and they showed that both apo- and holo-ferritin in the microenvironment promoted the proliferation of breast cancer cells without altering intracellular iron [177]. This evidence concerns the gene CD68 and breast cancer.