ATG5 and cancer: However, scientists also notice that the defective autophagy in normal cells is associated with genomic instability as well as tumorigenesis.38 For example, mice with deficiency of Atg5 and Atg7 easily develop liver cancer because of oxidative stress and mitochondrial damage.39 Therefore, autophagy plays a significant role in the process of cancer development and progression, with both cancer‐suppressive and cancer‐promoting function.