PPA1 and endometriosis: As shown in Figure 3A, the levels of GRP78 and PPA1 expression were higher in the GnRHa- (untreated) group compared with the GnRHa + (GnRHa-treated) group (P <0.05), while EFHA2 and TGM2 expression significantly increased in endometriosis patients after GnRHa treatment (P <0.05).