CNPY2 and ischemic stroke: CNPY2, a newly discovered transmembrane protein located in the ER, is a key promoter of the unfolded protein reaction, and is mainly involved in ERS.[17] In hepatocarcinoma, CNPY2 is highly expressed and participates in the occurrence and development of hepatocarcinoma by inhibiting and activating oncogenes via unfolded protein reaction‐dependent p53.[30] Zhao et al.[31] reported that in a rat model of ischemic stroke, berberine improved neuronal apoptosis by inhibiting CNPY2‐induced ERS overactivation.