CXCR4 and myocardial infarction: Considering the modified microenvironment due to a myocardial infarction, in which cells exposed to hypoxic stress will release SDF1α, the augmented CXCR4 expression demonstrated in this work would increase the homing of cells treated with SiO2-NPs towards the injured area, potentially improving the therapeutic efficacy of the transplanted cells.