HSPA5 and Alzheimer disease: These AD-induced changes activate a TGF-β receptor signaling apoptotic cascade, resulting in an endoplasmic reticulum (ER) stress-induced activation of the Unfolded Protein Response (UPR), as documented by transcription and translational upregulation of GRP-78 (also known as BiP or HSP5a) and Calmodulin (CaM) [13,14].