(d) Representative immunoblots showing high autophagy levels in normal cells and low levels in stem cells and cancer cells. Autophagic flux (autophagic activity) was measured by changes in the levels of LC3-II, in the presence or absence of lysosomal inhibitors E64d-PepA. U, uninhibited. I, inhibited. Below, the average of the percentage change in LC3-II levels after lysosomal inhibition from three experiments. α-tubulin, loading control. 