Since DDR-defective tumors are more sensitive to PARP inhibitors (i.e., olaparib)17 and cell cycle checkpoints are the targets of Wee1 inhibitors (i.e., AZD1775)18, we hypothesize that knockdown of E-cadherin expression would sensitize GC cell lines to olaparib or/and AZD1775. This evidence concerns the gene WEE1 and gastric cancer.