Establishment of a continuous cell line from a human carcinoid of the small intestine (KRJ-I).

A new continuous cell line from a human malignant carcinoid of the small intestine (KRJ-I) was established. The cells showed morphological and immunocytochemical features of the tumor of origin and expressed estrogen receptors. The cells are growing as a suspension, forming multicellular aggregates and spheroids. Electron microscopy confirmed the presence of neuroendocrine granules. Dose-dependent growth inhibition was observed after incubation with 5-azacytidine. Cytogenetic analyses of the tumor of origin, the cell line KRJ-I and a liver metastasis KRJ-II revealed clonal tetraploidy and clonal loss of the Y-chromosome and chromosome 19.