title: Human lung small-cell carcinoma contains bombesin.
abstract: The presence of immunoreactive bombesin in a human lung small-cell carcinoma grown in nude mice was established by several criteria: (i) Radioimmunoassay of tissue extracts for bombesin revealed approximately 6.5 pmol/g of tissue; (ii) bombesin was found in 12-14% of the tumor cells by immunohistochemical localization; (iii) gel filtration of small-cell carcinoma extract on Sephadex G-75 and Bio-Gel P-4 gave only a single peak of immunoreactivity, which occurred at the elution volume of bombesin; and (iv) reverse-phase HPLC of acid-solubilized extracts separated the immunoreactive material into three discrete peaks, one of which eluted with a retention time identical to that of synthetic bombesin. The presence of bombesin may represent the ectopic expression of this peptide in small-cell carcinoma, because immunoreactive bombesin was found in human fetal and neonatal lung but apparently not in adult lung tissue [Wharton, J., Polak, J. M., Bloom, S. R., Ghatei, M. A., Solcia, E., Brown, M. R. & Pearse, A. G. E. (1978) Nature (London) 273, 769-770]. The immunoreactive bombesin previously found in mammalian tissues is considerably larger than amphibian bombesin; these data substantiate the presence of a mammalian form of bombesin in a human tumor that may have a structure similar to that of the amphibian peptide.
mesh_terms: D000818:Animals; D001839:Bombesin / Q000032:analysis*; D018288:Carcinoma, Small Cell / Q000032:analysis*; D002850:Chromatography, Gel; D006651:Histocytochemistry; D006801:Humans; D007158:Immunologic Techniques; D008175:Lung Neoplasms / Q000032:analysis*; D008297:Male; D051379:Mice; D008819:Mice, Nude; D008875:Middle Aged; D010455:Peptides / Q000032:analysis*; D011863:Radioimmunoassay
chemical_list: D010455:Peptides; D001839:Bombesin