Figure 6.

Proposed model for the role of CD47 overexpression in drug resistance of multiple myeloma (MM). Low level of miR-155 in drug resistant cells leads to upregulation of CD47 expression, which results in activation of 'do not eat me' signal and inhibition of phagocytosis by macrophages. miR-155 can also target anti-apoptotic gene, TNFAIP8 which inhibits apoptosis through caspase 8 inactivation. On the other hand, TNFAIP8 can regulate miR-155 expression level through a negative feedback loop.