LRP6 and cancer: Moreover, GRP94 is responsible for chaperoning multiple proteins that have been reported to play essential roles in immune response and promoting cancer development, including Toll-like receptors (TLRs) (5–8), the majority of α and β integrin subunits (7, 9), Wnt co-receptor low-density lipoprotein receptor-related protein 6 (LRP6) (9, 10), glycoprotein A repetitions predominant (GARP) (11–15), Insulin-like growth factor (IGF) (16–18), as well as platelet glycoprotein Ib-IX-V complex (19) (Figure 1A).