SLFN5 and breast cancer: In our previous study, we found that stabilized dephosphorylated β-catenin translocates into the nucleus in SLFN5-siRNA-treated breast cancer MCF7 cell lines [16], so we primarily examined GSK-3β/β-catenin and its up- and downstream signaling molecules in A549 cells, observing that the GSK-3β/β-catenin pathway was regulated in response to SLFN5 in A549 cells, i.e., activated by SLFN5 knockdown, and was blocked in response to SLFN5 overexpression (Figure 4(a)).