Abstract 972: B-cell maturation antigen (BCMA) activation in human multiple myeloma cells promotes myeloma cell growth and survival in the bone marrow microenvironment via upregulated MCL-1 and NFκB signaling

B cell maturation antigen (BCMA), a member of the tumor necrosis factor receptor superfamily (TNFRSF17), is selectively induced during plasma cell (PC) differentiation and is commonly expressed at high levels in malignant PCs. Using real time RT-PCR, we here first showed that BCMA mRNA was upregulated in CD138+ PCs from MM patients compared to normal healthy donors, consistent with high and restrictive BCMA expression in PCs but not normal tissues by gene expression profiling and immunohistochemistry in previously published reports. As a specific MM antigen, BCMA is universally expressed on the MM cell surface, confirmed by CD38+BCMA+ dual immunofluorescence staining. We next found that plasmacytoid dendritic cells (pDC), which support MM cell growth, survival, and drug resistance in the bone marrow (BM) microenvironment, have detectable BCMA mRNA at significantly (9-50-fold) lower levels than CD138+ plasma PCs (p Citation Format: Yu-Tzu Tai, Chirag Acharya, Mike Y. Zhong, Michele Cea, Antonia Cagnetta, Paul Richardson, Nikhil C. Munshi, Kenneth C. Anderson. B-cell maturation antigen (BCMA) activation in human multiple myeloma cells promotes myeloma cell growth and survival in the bone marrow microenvironment via upregulated MCL-1 and NFκB signaling. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 972. doi:10.1158/1538-7445.AM2014-972