PIK3CA and cancer: Activation of independent proliferation pathways (Rozengurt et al., 2014; O’Reilly et al., 2006) and alterations of downstream targets, such as eIF4E and 4E-BP1 (Alain et al., 2012; Cope et al., 2014; Jastrzebski et al., 2018), may represent alternative strategies for cancers to acquire resistance to PI3K and mTOR inhibition.