Two human myeloma cell lines, amylase‐producing KMS‐12‐PE and amylase‐non‐producing KMS‐12‐BM, were established from a patient, having the same chromosome marker, t(11;14)(q13;q32)

Two human myeloma cell lines, KMS‐12‐PE and KMS‐12‐BM, were established from a 64‐year‐old woman with a non‐producing type of multiple myeloma. The KMS‐12‐PE line originated from the pleural effusion and the KMS‐12‐BM from the bone marrow. These two lines showed the same chromosome marker, t(11;14)(q13;q32). However, their phenotypes of surface markers differed from each other. KMS‐12‐BM cells were positive to CD20, CD38 and PCA‐1, showing the plasmacytoid (immature plasma cell) stage of B‐cell differentiation, while KMS‐12‐PE cells were positive to CD38 and PCA‐1, but not to CD20, indicating the terminal differentiated stage of B‐cells. As seen in the pleural effusion of the patient, KMS‐12‐PE cells ectopically produced a salivary type of amylase, but KMS‐12‐BM cells did not. Interestingly, the chromosome abnormality of del(1)(p22→pter) near the region of Ip21, where the amylase gene was assigned, was noticed in as many as 76% of KMS‐12‐PE cells.