PCSK1 and plasma cell myeloma: Interestingly, many genes up-regulated in JL cells function in disease pathways implicated in neurodegeneration and cancer: SRC homology domain-containing protein 21 (SH3D21) (ataxia-telangiectasia and colorectal cancer [27]), exocyst complex component 3-like protein 2 (EXOC3L2) (Alzheimer disease [28]), DEXH (Asp-Glu-X-His) box polypeptide 58 (DHX58) (mammary tumor [29]), proprotein convertase subtilisin/kexin type 1 inhibitor (PCSK1N) (skin carcinogenesis, Alzheimer disease and parkinsonism-dementia [30]), and jagged 2 (JAG2) (myeloma [31]) (Fig 1I and S3 Table).