HSPA5 and cancer: Five well-studied and important HSP70 family members are implicated in cancer development including stress-inducible HSP70s—cytosolic Hsp70 (HSPA1 or HSP72) and HSPA6 (HSP70B), constitutively expressed HSP70s—cytosolic HSC70 (HSPA8), mitochondrial mortalin (HSPA9), and GRP78 (HSPA5) which is mainly localized to ER [16].