ATG5 and cancer: Similarly, under serum deprivation conditions, MSCs were able to limit the induction of apoptosis in lung cancer cell lines through activation of autophagy.224 Interestingly, CAFs also resist stress better than normal fibroblasts, as fibroblasts isolated from ovarian cancer patients were more resistant to oxidative stress, with sensitivity being restored by Beclin‐1 or ATG5 knockout.221 Thus, autophagic signaling in stromal fibroblasts and MSCs can contribute to survival and growth of cancer cells.