SEMA7A and neoplasm: As showed in Figure 2C, Proteinase K completely removed SEMA7A, similarly to the multipass membrane tetraspanin CD9, while the inner TSG101 (Tumour Susceptibility Gene-101) was not affected by digestion, supporting the idea that SEMA7A is exposed on the external side of exosomes and therefore could signal directly on the target cells.