Arai et al. reported that combining navitoclax (through Bcl-xl inhibition) with several kinase inhibitors (erlotinib, lapatinib, cabozantinib, sorafenib) induces rapid and significant apoptosis in PC cells after RNAi or CRISPR-mediated knockdown of MCL1 expression (Arai et al., 2018). This evidence concerns the gene MCL1 and pachyonychia congenita.