In addition, mice receiving the combination treatment showed an increased expression of Bcl2l1 (encoding the navitoclax target BCL-xL), raising the possibility that, as has been observed in models of non-Hodgkin lymphoma,67 increased BCL-xL levels may contribute to BCL-2/BCL-xL inhibitor resistance. Here, BCL2 is linked to non-Hodgkin lymphoma.