“…One critical success factor of CRT is the use of feeder cells and ROCK inhibitors to help tumor cells and other epithelial cells proliferate continuously in vitro ( Figure 1 A) [ 62 , 63 , 64 ]. At present, multiple cancer cells have been established using CRT [ 64 ], including adenoid cystic carcinoma [ 65 ], breast [ 66 ], prostate [ 67 , 68 ], pancreatic [ 69 ], colorectal [ 70 ], lung [ 71 , 72 ], cervical [ 73 ], skin, kidney, ovarian cancers, and so on [ 64 , 74 ]. In addition, conditionally reprogrammed cells can be generated from PDX models and organoids [ 75 , 76 , 77 ] and passaged more than 200 times while preserving the heterogeneity of tumor cells [ 78 , 79 ].…”