XBP1 and gastroesophageal reflux disease: On the other hand, in another meta-analysis, HP treatment decreased GERD symptoms.18 In our study, the expression of the ATF-6, XBP-1, EIF-2-AK, DNAJC-9, ERN-1, and NF-2-L-2 mRNAs was significantly decreased after treatment in HP-positive patients.