Cytokine that binds to TNFRSF13B/TACI and to TNFRSF17/BCMA. Plays a role in the regulation of tumor cell growth. May be involved in monocyte/macrophage-mediated immunological processes. Homotrimer. Expressed at high levels in transformed cell lines, cancers of colon, thyroid, lymphoid tissues and specifically expressed in monocytes and macrophages. Down-regulated by phorbol myristate acetate/ionomycin treatment. The precursor is cleaved by furin. Belongs to the tumor necrosis factor family.