AKT1 and breast carcinoma: MSC‐derived exosomes contain tumour supportive miRNAs, tumour supportive factors, bioactive lipids, lactic acid and glutamic acid, which support breast cancer cell proliferation and metastasis,49 whereas MSC‐derived exosomes induce tumour‐associated microenvironment and endow gastric cancer cells with stemness by activating Akt signalling pathway.50