Several epitopes, such as syndecan-1 (CD138), X-box–binding protein 1 (XBP1)-unspliced, XBP1-spliced, CS1, have been identified as potential targets in multiple myeloma (MM) and smoldering multiple myeloma (SMM), and their applications against MM and SMM were also very effective (348–350). The gene discussed is XBP1; the disease is AL amyloidosis.