PTEN and breast cancer: It has been established that EVs mediate the transfer of histones, oncogenic species (EGFRvIII) [41], non-coding RNA (miRNA) [20] and tumour suppressors (PTEN) in glioma cells [16] and that therapeutically resistant cancer cells can transfer this resistance to sensitive cancer cells via EVs in renal cancer, breast cancer and colorectal cancer [22,24,42].