Our group recently identified AhR as a poor prognostic factor in multiple myeloma patients that positively regulates the polyamine biosynthesis through transcriptional regulation of key players ornithine decarboxylase 1 (ODC1) and antizyme inhibitor 1 (AZIN1), and supports multiple myeloma cell proliferation (18). The gene discussed is AZIN1; the disease is AL amyloidosis.