Stimulatory effect of EGF and inhibitory effect of sialoadenectomy on growth of an EGF receptor-hyperproducing human gastric cancer xenograft in nude mice.
We recently established epidermal growth factor (EGF) receptor-hyperproducing human gastric cancer xenografts in nude mice. The present study was designed to examine whether the growth of a xenograft having 1,098 +/- 276 fmol/mg protein of EGF receptor would either be stimulated by the administration of EGF or inhibited by the removal of the submandibular glands (sialoadenectomy) which contain a large amount of EGF. A miniosmotic pump containing 2 micrograms or 20 micrograms of EGF was implanted on the back of the animals in the EGF stimulation experiments. The tumor growth was stimulated by the administration of EGF (P < 0.01), and the doubling time of the tumor was reduced relative to the controls (P < 0.01). Both the mitotic indices and the bromodeoxyuridine (BrdU)-labeling indices of the tumor were higher than those of the controls (P < 0.01). Tumor growth inhibited by the sialoadenectomy (P < 0.05) while the tumor doubling time was prolonged compared with the sham-operated mice (P < 0.05). These results suggest that the growth of a human gastric cancer xenograft may be modulated by EGF.
Okuda
T
T
First Department of Surgery, Nippon Medical School, Tokyo, Japan.
Onda
M
M
Tokunaga
A
A
Sugisaki
Y
Y
D000230:Adenocarcinoma / Q000378:metabolism*; D000818:Animals; D002453:Cell Cycle; D004815:Epidermal Growth Factor / Q000302:isolation & purification / Q000494:pharmacology* / Q000652:urine; D066246:ErbB Receptors / Q000096:biosynthesis*; D006128:Growth; D006801:Humans; D007150:Immunohistochemistry; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D013268:Stimulation, Chemical; D013274:Stomach Neoplasms / Q000378:metabolism*; D013363:Submandibular Gland / Q000601:surgery*; D014183:Transplantation, Heterologous; D014407:Tumor Cells, Cultured
D004815:Epidermal Growth Factor; D066246:ErbB Receptors