We report here the identification, characterization and subcellular localizations of two novel anchorless endogenous SEL1L variants, p38 and p28, studied in the breast cancer cell lines SKBr3 and MCF7, the multiple myeloma line KMS11 and the non-tumorigenic lines MCF10A (breast) and 293FT (embryo kidney). The gene discussed is SEL1L; the disease is plasma cell myeloma.