BECN1 and cancer: On the other hand, excessive autophagy in apoptosis‐deficient cells could trigger massive cell death, thereby sensitizing cancer cells to the chemodrugs.33 Previous study has shown that USP14 could negatively regulate autophagy by removing ubiquitin chains of Lys63 from Beclin‐1.34 Thus, to explore the role of USP14 in autophagy in GC cells, we determined the levels of LC3A/B I and LC3A/B II in USP14‐depleted MKN45 and KATO III cells, and observed a high ratio of LC3A/B II to LC3A/B I expression, indicating these cells were undergoing autophagy (Figure S3).