CHARACTERIZATION OF 4 NEW CELL-LINES DERIVED FROM SMALL-CELL GASTROINTESTINAL CARCINOMA

Four human small-cell gastrointestinal carcinoma cell lines were estab lished from tumor tissues of patients with esophageal, gastric or rect al cancer, and were studied morphologically and biochemically in compa rison with small-cell lung carcinoma (SCLC) cell lines and common gast ric cancer cell lines. Cells from all the small-cell gastrointestinal carcinoma lines were as small as classic SCLC cells and had characteri stic neurosecretory granules. Cells from only one line grew as tightly packed spherical aggregates of floating cells, and those of the other 3 grew attached to substrate. Although high levels of creatine kinase brain isoenzyme (CK-BB) were detected in all 4 cell lines, 2 of them showed low levels of aromatic L-amino-acid decarboxylase and 3 had low levels of neuron-specific enolase (NSE). None of the lines showed sim ultaneous elevation of enzymes. C-myc, N-myc, and L-myc were not ampli fied in any of the cell lines, but c-myc mRNA was expressed in 2 lines . Our findings indicate that all small-cell gastrointestinal carcinoma cells examined belong to the variant type which is used in the classi fication of SCLC. Furthermore, the ECC18 line, derived from esophageal cancer, seemed to be of true endocrine cell origin, while the 3 other small-cell gastrointestinal carcinoma lines seemed to arise via neopl astic neometaplasia from adenocarcinoma cells to endocrine cells. (C) 1993 Wiley-Liss, Inc.