Yeung et al. showed that cancer-associated fibroblasts (CAFs) secretes microfibril associated protein 5 (MFAP5), which causes increased expression of fibrosis-related genes thus, increasing the amount of collagen, which together with decreasing microvessel stability (more leakiness of vessels) leads to hindrance in the delivery of drugs [10]. This evidence concerns the gene MFAP5 and cancer.