HSPA9 and cancer: Our data showed that: (1) CME was inhibited whereas CIE was unchanged or even up-regulated in the M-phase of the cell cycle; (2) GRP75 inhibited CME but promoted CIE in the M-phase, which is due to its high expression in cancer cell mitochondria; and (3) GRP75 targeting enhanced cell cycle G1-phase-privileged CME, which provides an opportunity for intracellular delivery of different size nanomicrospheres.