To evaluate whether the inhibition of platelet aggregation by S14161 is due to platelet apoptosis because S14161 has been shown to induce myeloma and leukemia cell apoptosis [23], we performed an Annexin V staining assay in which Annexin V specifies phosphatidylserine (PS) exposure on the outside of plasma membrane. This evidence concerns the gene ANXA5 and plasma cell myeloma.