Fig. 1

a - ADC structure: An ADC is composed of an antibody coupled to cytotoxic drugs by linkers. b - ADC trafficking and processing classic model: The ADC binds to its surface antigen (1) and the complex is internalized (2), it reaches lysosomes where its linker of the ADC is degraded leading to the release of the drug (3), the drug passes from the intracellular compartment to the cytosol (4), and binds to its target, DNA or tubulin (5) ensue apoptosis. It may also be released into the microenvironment via pumps or passive transfer through the cell membrane (6), capacity to enter a neighbor cancer cell (7) resulting in bystander effect. c- Endocytosis and autophagy pathways