[Detection of CgA mRNA in neuroendocrine cells in gastric carcinoma by in situ hybridization].

Fresh gastric carcinoma specimens from 17 cases were collected. The neuroendocrine (NE) cells in gastric carcinoma (GC) and gastric mucosa adjacent to the carcinoma (GMAC) were observed using in situ hybridization of chromogranin A (CgA) oligonucleotide probe and compared with immunohistochemistry of CgA antibody. 5 of the 17 cases of GC showed CgA mRNA positive expression and 7 of the 17 cases expressed CgA protein positively. The simultaneous expression of mRNA and protein of CgA was present in 4 cases. The NE cells in GC not only can store and secrete CgA protein products but also possess the ability to synthesize NE products from gene expression.