The combination treatment of bevacizumab with a Hsp90 inhibitor, 17‐N‐allyamino‐17‐demothoxygeldanamycin (17AAG), can restore the bevacizumab sensitivity of EV surface VEGF and inhibit tumour growth in a breast cancer patient‐derived xenograft model through 17AAG localizing to microvesicles (MVs), binding VEGF90K and releasing this VEGF, thus increasing the efficacy of bevacizumab.39 This evidence concerns the gene VEGFA and breast carcinoma.