Multiple gastrin-releasing peptide gene-associated peptides are produced by a human small cell lung cancer line

• Published in: The Journal of biological chemistry 1989-02, Vol.264 (4), p.1928-1932
• Main Authors: Reeve, J R, Cuttitta, F, Vigna, S R, Heubner, V, Lee, T D, Shively, J E, Ho, F J, Fedorko, J, Minna, J D, Walsh, J H
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Biological and medical sciences; cancer; Carcinoma, Small Cell - genetics; Cell Line; Chromatography, High Pressure Liquid; Cloning, Molecular; DNA, Neoplasm - genetics; Fundamental and applied biological sciences. Psychology; Gastrin-Releasing Peptide; Gastrointestinal Hormones - genetics; Genes; Humans; lung; Lung Neoplasms - genetics; man; Molecular and cellular biology; Molecular genetics; Molecular Sequence Data; Peptide Fragments - isolation & purification; Peptides - genetics; Protein Sorting Signals - genetics; RNA, Messenger - genetics; Translation. Translation factors. Protein processing
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1016/S0021-9258(18)94122-0

Products of the gastrin-releasing peptide gene were isolated from culture medium supernatant of a small cell lung cancer line, NCI-H345, by several (high performance liquid chromatography) HPLC steps. The column eluates were monitored by immunoassay and absorbance profiles. Gastrin-releasing peptide was identified in HPLC eluates by a specific radioimmunoassay. Two carboxyl-terminal gastrin-releasing peptide gene-associated peptides were identified by a radioimmunoassay specific for their predicted carboxyl terminus. The amino termini of these two peptides were determined by microsequence analysis. The shorter peptide was revealed to be a fragment of the larger peptide. Expression of an alternate mRNA was shown by isolation and characterization of a novel tetradecapeptide. Amino acid analysis, microsequence analysis, and mass spectral analysis confirmed that the structure was Ser-Leu-Leu-Gln-Val-Leu-Asn-Val-Lys-Glu-Gly-Thr-Pro-Ser. This peptide represents the carboxyl terminus of a peptide resulting from alternate processing of gastrin releasing peptide mRNA. This mRNA contains a 19-base deletion, creating a frame shift. A radioiodinated synthetic analog of this peptide (Tyr-Leu-Val-Asp-Ser-Leu-Leu-Gln-Val-Leu-Asn-Val-Lys-Glu-Gly-Thr-Pro-Ser) bound specifically to a small cell cancer line with high affinity, suggesting possible biological activity of the isolated peptide.