CTTN and Lambert-Eaton myasthenic syndrome: Cortactin antibodies (Y7 in Figure 1) were detected in some of the MG patients (Gallardo et al., 2014; Cortés-Vicente et al., 2016; Illa et al., 2018), and also found in a patient with Lambert-Eaton myasthenic syndrome (a presynaptic autoimmune disease; Gallardo et al., 2014); this may reflect the fact that cortactin expresses in the presynaptic side (Peng et al., 1997) and acts as the Wnt signaling-dependent presynaptic effector molecule (Alicea et al., 2017).