This finding seems to be partly consistent with a recent report by Xu et al. [15] who found that ARID5B knockdown in ALL cell lines led to specific resistance to MTX and 6MP. The authors showed that knockdown of ARID5B by using shRNA and CRISPR/Cas9 in ALL cell lines induced partial cell-cycle arrest at G0/G1 phase through upregulation of p21 [15], suggesting that cell-cycle arrest mediated by p21 may be involved in the induction of resistance to MTX and 6MP. Here, ARID5B is linked to acute lymphoblastic leukemia.