Abstract
A new human somatostatinoma cell line, Soma-1, was established from a surgical specimen of a 64-year-old man. Soma-1 cells showed polygonal morphology with neurites and proliferated as an adherent monolayer with an approximate population doubling time of 48 hours. Electron microscopic observation revealed that Soma-1 cells have large nuclei with several nucleoli, scant cytoplasm with dense bodies (possibly secretion granules), and scattered Golgi apparatus and mitochondria. Cell surface microvilli were not apparent. Xenotransplantation of Soma-1 into BALB/c nude mice did not produce visible tumors. Significant somatostatin and neuron-specific enolase activities were observed in both extracellular (by radioimmunoassay) and intracellular fractions (by immunohistochemistry), suggesting neuronal differentiation. Soma-1 is more resistant to various apoptosis-inducing agents than are human myelogenous leukemic cell lines. This cell line provides a useful in vitro model for the pathophysiologic analysis of somatostatinoma.
