LOX and neoplasm: ECM remodeling and stiffening are mechanical and biological events, which increase the stroma resistance to assault of pH and proteolytic degradation [24,25], and include a protease-dependent collagen cross-linking mechanism, which is related to lysyl oxidase (LOX) secretion by hypoxic tumor cells, but also a non-enzymatic collagen cross-linking process, which is related to glycation and transglutamination or to an increased deposition of proteoglycans [26].