ABSTRACT
The effect of human epidermal growth factor (hEGF) on the growth of various histological types of six human gastric carcinoma cell lines was examined. The cell lines had relatively high affinity EGF receptors (dissociation constant Kd = 10(-9) to 10(-10) M). One gastric cancer cell line, MKN-74 (well differentiated adenocarcinoma) showed no response to hEGF, in cell growth, DNA synthesis or 125I-hEGF cell binding. There were no apparent correlations between histological type and cell growth, DNA synthesis or number of EGF receptors in these cells. The number of EGF receptors and the Kd value of the gastric carcinoma cell lines varied with their internal and external environments. hEGF concentrations corresponding to maximum stimulation in DNA synthesis varied between cell lines. The results suggest some gastric carcinoma cells to have EGF receptors and their growth seemingly to be stimulated by EGF in vitro. There are, however, no obvious correlations between the effect of hEGF on the growth of human gastric carcinoma cell lines or their histological type.
Subject(s)
Adenocarcinoma/pathology , Epidermal Growth Factor/pharmacology , ErbB Receptors/metabolism , Stomach Neoplasms/pathology , Adenocarcinoma/metabolism , Cell Division/drug effects , Cell Line/drug effects , DNA Replication/drug effects , Dose-Response Relationship, Drug , Humans , Kinetics , Stomach Neoplasms/metabolism , Temperature , Time FactorsABSTRACT
Serotonin was examined immunohistochemically in seven tubular adenomas, 194 adenocarcinomas and 41 endocrine cell tumours of the stomach. In tubular adenomas, serotonin-containing cells showing argentaffinity were present in the lower portion of the adenomatous glands and were considered to be an expression of intestinal character. Scattered serotonin-containing tumour cells were found in 60 (30.9%) of 194 adenocarcinomas regardless of their histological type. Cell fusions between carcinoma and enterochromaffin (EC) cells might be a possible mechanism for the occurrence of serotonin-containing cells within the tumour. In 17 (54.8%) of 31 endocrine cell carcinomas, serotonin-containing tumour cells were observed in a variable degree in contrast to the absence of these cells in classical carcinoid. Moreover, diffuse serotonin reactivity was found in four cases of scirrhous endocrine cell carcinoma. The histogenesis and the occurrence of serotonin-containing cells in each type of gastric tumour is also discussed.
