FN1 and cancer: Tensins 1‐3 (components of fibrillar adhesions) and Arf4 coordinate endocytosis of α5β1 integrin and associated matrix proteins (eg, fibronectin) to late endosomes/lysosomes, where they contribute to nutrient sensing via mTOR (mammalian target of rapamycin) and cancer cell invasion61 (Figure 3).