53BP1 loss induces chemoresistance of colorectal cancer cells to 5-fluorouracil by inhibiting the ATM–CHK2–P53 pathway

Purpose Loss of P53 binding protein 1 (53BP1) is considered a poor prognostic factor for colorectal cancer. However, its effect on chemosensitivity of colorectal cancer to 5-fluorouracil (5-FU) remains elusive. This study aimed to examine the association of 53BP1 expression with chemosensitivity of colorectal cancer cells to 5-FU.