CD38 and plasma cell myeloma: Consistent with recent findings that deletion of pink1 or park2 promoted mutant Kras‐driven pancreatic tumorigenesis,15 we found that XBP‐1s+/+/pink1−/− mice had accelerated development of myeloma manifested by increased osteoclasts, higher levels of bone marrow and spleen CD38+ plasma cells and serum IgG, the development of M protein and bone lytic lesions.