Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0684249 (lung carcinoma)
 23,830 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Production of the growth factor gastrin-releasing peptide (GRP) or human bombesin has been shown to be a feature of neuroendocrine tumours of the lung, particularly small cell carcinoma, and is possibly responsible for the characteristically rapid growth of this tumour. Large cell undifferentiated carcinoma of the lung (LCC) is also characterized by rapid growth and there is increasing evidence that some LCCs exhibit neuroendocrine differentiation. We therefore investigated GRP/bombesin immunoreactivity and the expression of GRP gene in ten LCCs. Histologically, all were composed of large cells with abundant cytoplasm, open nuclei, and prominent nucleoli, and there was no evidence of squamous, glandular, or neuroendocrine differentiation. At the ultrastructural level, most showed squamous or glandular differentiation but none contained neuroendocrine granules. None of the tumours showed immunoreactivity for GRP/bombesin but seven of the ten showed a focal hybridization signal when treated with 32P-labelled GRP cRNA probes, indicating the presence of GRP mRNA. This was confirmed by northern blot analysis. This study shows for the first time that GRP gene is expressed in LCC. The production of GRP may contribute to the aggressive behaviour of LCC.
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PMID:Expression of gastrin-releasing peptide (human bombesin) gene in large cell undifferentiated carcinoma of the lung. 216 49

A sensitive radioimmunoassay (RIA) system for plasma gastrin-releasing peptide (GRP) was developed using immune-affinity chromatography for plasma extraction. Plasma neuron-specific enolase (NSE) levels were determined by use of RIA without extraction. Plasma GRP levels in 12 control subjects were (mean +/- SD) 1.2 +/- 0.26pg/ml. Plasma GRP levels were elevated at frequencies of 79% in untreated patients with small cell lung carcinoma (SCLC). The levels in 21 patients with non-SCLC were not elevated. In nine of 10 patients with complete response (CR) or partial response (PR), plasma GRP levels decreased significantly when the patients were judged to have achieved CR or PR. In four patients with progressive disease (PD), the levels were elevated after treatment when compared with levels before treatment. In six of 10 patients with CR or PR, plasma NSE levels decreased significantly at the judgment of CR or PR. In two of four patients with PD, the levels were elevated after treatment. Furthermore, changes in plasma GRP level showed more excellent correlation with the therapeutic response than changes in plasma NSE level in the clinical courses of two patients with CR and a patient with PD. These results suggest that the plasma GRP level could be a useful tumor marker in SCLC patients.
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PMID:[Gastrin-releasing peptide as a specific tumor marker in patients with small cell lung carcinoma, compared with neuron-specific enolase]. 216 19

Levels of gastrin-releasing peptide (GRP) were determined by radioimmunoassay in human normal main and lobar bronchus and parenchymal lung tissue extracts. It was found that the level of GRP differed significantly between all 3 areas. The concentration of GRP was statistically higher in main bronchus (median 6.74 ng/g) compared to both lobar bronchus (median 4.79 ng/g) and parenchymal lung (median 1.73 ng/g), and also statistically higher in lobar bronchus compared to parenchymal lung. Chromatographically, GRP-immunoreactivity in both main and lobar bronchial extracts corresponded to GRP1-27 and GRP18-27, while in lung tissue only one major species was identified which corresponded in retention time to GRP18-27. No significant difference was detected when the levels of GRP in normal lobar bronchus and normal lung tissue were compared to the levels in lobar bronchus and lung taken from patients with lung carcinoma, at a site adjacent to the carcinoma. However, a significant difference was observed between the GRP content of normal main bronchus compared to main bronchus from patients with carcinoma. GRP was measured in 26/56 lung carcinomas examined. The levels ranged from 42,000 ng/g in a carcinoid tumour to 0.18 ng/g in a squamous-cell carcinoma, though only in 6 tumours were the levels outside the range determined for normal pulmonary tissue. Chromatography of selected tumour extracts of different histopathologies showed that there were differences in the GRP products present.
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PMID:Gastrin-releasing peptide in normal and neoplastic human lung: measurement and biochemical characterization. 217 Feb 79

The neuropeptide bombesin is known for its potent mitogenic activity on murine 3T3 fibroblasts and other cells. Recently it has been implicated in the pathogenesis of small cell lung carcinoma, in which it acts through an autocrine loop of growth stimulation. Phosphotyrosine (P-Tyr) antibodies have been successfully used to recognize the autophosphorylated receptors for known growth factors. In Swiss 3T3 fibroblasts, phosphotyrosine antibodies identified a 115,000-Mr cell surface protein (p115) that became phosphorylated on tyrosine as a specific response to bombesin stimulation of quiescent cells. The extent of phosphorylation was dose dependent and correlated with the mitogenic effect induced by bombesin, measured by [3H]thymidine incorporation. Tyrosine phosphorylation of p115 was detectable minutes after the addition of bombesin, and its time course paralleled that described for the binding of bombesin to its receptor. Immunocomplexes of phosphorylated p115 and phosphotyrosine antibodies bound 125I-labeled [Tyr4]bombesin in a specific and saturable manner and displayed an associated tyrosine kinase activity enhanced by bombesin. Furthermore, the 125I-labeled bombesin analog gastrin-releasing peptide, bound to intact live cells, was coprecipitated with p115. These data strongly suggest that p115 participates in the structure and function of the surface receptor for bombesin, a new member of the family of growth factor receptors with associated tyrosine kinase activity.
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PMID:Receptor for bombesin with associated tyrosine kinase activity. 243 4

The production of human bombesin (gastrin-releasing peptide), a peptide with mitogenic action, is a recognized feature of neuroendocrine (small cell) carcinoma of the lung. However, immunostaining of bombesin is not always possible in these tumors, probably because of poor storage mechanisms or rapid release of hormone. Molecular biological analysis of the gene encoding human bombesin has revealed the DNA sequence of human pro-bombesin. We have used in situ hybridization to study the expression of the human bombesin gene at the cellular level in small cell carcinoma of the lung. Probombesin cDNA was subcloned in pSP64 vector, linearized with Bam HI and transcribed in the presence of phosphorus 32(32P)-cytosine triphosphate (CTP) and SP6 polymerase. The cRNA probe was applied to tissue sections (from six cases of small cell carcinoma of the lung, freshly fixed in 4% paraformaldehyde), cell culture preparations (two different cell lines of small cell carcinoma), and cytologic specimens (smears of cells from three different cases of small cell carcinoma). Hybridization of probombesin mRNA was detected in tumor cells in all samples. Specificity of the signal was determined by control experiments, including the use of a probe which has a sequence identical to probombesin mRNA. Our results provide evidence for the expression of the bombesin gene in small cell carcinoma of the lung at a cellular level and show that probombesin mRNA is highly expressed in these tumors.
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PMID:Detection of human probombesin mRNA in neuroendocrine (small cell) carcinoma of the lung. In situ hybridization with cRNA probe. 253 54

Gastrin-releasing peptide (GRP) is now known to be a very common product of small cell lung carcinoma (SCLC). With the aim of investigating the possible role of this peptide as a tumor marker of SCLC, we have developed a sensitive radioimmunoassay system for plasma immunoreactive GRP using immune-affinity chromatography for plasma extraction. Plasma immunoreactive GRP levels in control subjects were determined by using 15 ml of plasma as the starting material (minimum concentration detectable, 0.8 pg/ml). The levels in 10 control subjects were (mean +/- SD) 1.2 +/- 0.27 pg/ml; range, 0.86-1.7 pg/ml. This assay system was applied for the clinical use by using 3 ml of plasma as the starting material (minimum concentration detectable, 4.0 pg/ml). Plasma immunoreactive GRP levels were elevated in SCLC patients at frequencies of 71% in patients with limited disease and 80% in those with extensive disease. Furthermore, a change in the level showed excellent correlation with the therapeutic response. In six patients with complete response who had had elevated levels before treatment, the levels decreased to an undetectable range when the tumor disappeared, and they remained undetectable until 1 month later, when the patients were judged to have achieved complete response. In the partial response group, plasma immunoreactive GRP levels had decreased to an undetectable level in two of three patients, when the patients achieved partial response. In four patients with progressive disease, plasma immunoreactive GRP levels were elevated at the time of the progressive disease judgment, when compared with levels before treatment. The levels in 21 patients with non-SCLC (10 with adenocarcinoma, seven with squamous cell carcinoma and four with large cell carcinoma) were not elevated. These results indicate the plasma immunoreactive GRP level as a useful tumor marker in SCLC patients. It is now believed that GRP can function as an autocrine growth factor for SCLC. The present study suggests that the possible autocrine growth factor could serve as a reliable tumor marker for cancer patients.
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PMID:Immunoreactive gastrin-releasing peptide as a specific tumor marker in patients with small cell lung carcinoma. 253 62

Small cell lung carcinoma (SCLC) is histologically simple, and shows a characteristic ultrastructure and very complex functions. Recently, a large amount of information has been accumulated by fundamental research, largely involving studies on many cultured cell lines. Now their potential application to the therapy of SCLC is being sought. A characteristic ultrastructural feature is the presence of dense-cored neurosecretory-type granules 100-200 nm in diameter. In addition, epithelial cell characteristics are noted. Predominance of either a neurosecretory or epithelial nature may affect the responsiveness of tumors to therapy. Many kinds of brain-gut hormones are produced by SCLC. Gastrin-releasing peptide (GRP) has attracted much attention as an autocrine growth factor for SCLC. Aromatic L-amino acid decarboxylase (AADC), neuron-specific enolase (NSE) and creatine kinase BB (CK-BB) are rather specific to SCLC. NSE and CK-BB together with GRP are good monitoring markers during treatment. Amplification of c-myc, N-myc and L-myc is seen in SCLCs. Areas both with and without N-myc amplification are found in both the primary site and metastatic sites in a single case. Del 3p(14-23) is characteristic for SCLC but SCLCs without such deletion are also present. A cytologically "variant" type is composed of cells simulating "large cells", in which the doubling time is short, AADC and GRP are undetectable, granules are rare, and the cells are resistant to radiation. However, one cell line of the classic type has revealed reversible squamous cell change in the absence of retinoic acid, becoming radioresistant without showing any remarkable changes in AADC, NSE or CK-BB. Since SCLC mixed with "large cells" or "small cell carcinoma of undifferentiated type" is resistant to therapy and possesses a more epithelial nature, small cell carcinoma with a large cell component has been proposed as a subtype. The question of whether this subclassification is practical should be confirmed by prospective study.
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PMID:[Pathology and biology of small cell lung cancer]. 283 14

Gastrin-releasing peptide (GRP), the mammalian homolog of the amphibian peptide bombesin, is encoded in man by a single gene located on chromosome 18. Restriction enzyme and DNA sequence analyses establish that the gene is 10 kilobases in size with two introns of 4.8 and 3.9 kilobases. Exon 1 encodes the 5'-untranslated region, the signal peptide, and the first 23 amino acids of GRP. Exon 2 encodes the remaining three complete amino acids of GRP and the first 74 amino acids of the GRP carboxy-terminal extension peptide. Hence, intron 1 interrupts the coding region of the bioactive portion of GRP between the first and second nucleotides for Gly, the 24th amino acid of GRP. Exon 3 encodes the remainder of the GRP-extension peptide and the 3'-untranslated region. Two GC-rich, potential regulatory sequences and a sequence associated with regulation by cAMP lie between the CAAT and TATA boxes; the primary transcriptional start site is located 30 bases downstream from the TATA box. The second intron has an alternate donor site at its 5'-end and an alternate acceptor site at its 3'-end. S1 nuclease mapping demonstrates that differential RNA splicing using these sites results in the similar expression of three GRP mRNAs in GRP-containing neurons (in stomach and brain) as well as in GRP-containing neuroendocrine cells (fetal lung). In addition, the pattern of RNA splicing is similar between normal tissue and neoplastic tissue (small cell carcinoma of the lung and medullary carcinoma of the thyroid).
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PMID:Analysis of the gene and multiple messenger ribonucleic acids (mRNAs) encoding human gastrin-releasing peptide: alternate RNA splicing occurs in neural and endocrine tissue. 284 May 64

The human small cell lung carcinoma (SCLC) cell line NCI-H345 constitutively produces gastrin-releasing peptide (GRP), a peptide homologous to the mitogen bombesin. In addition, NCI-H345 cells express bombesin receptors and respond to bombesin with rapid activation of phospholipase C and mobilization of intracellular Ca2+. Treatment of NCI-H345 cells with a novel potent bombesin receptor antagonist [Leu13-psi-CH2NH-Leu14]bombesin blocked the increase in phosphatidylinositol turnover and cytoplasmic free Ca2+ ([Ca2+]i) stimulated by bombesin. Furthermore [Leu13-psi-CH2NH-Leu14]bombesin inhibited NCI-H345 colony formation in defined semisolid medium in the absence of exogenous GRP. The rapid, hormone-induced accumulation of inositol(1,4,5)trisphosphate was markedly more sensitive to antagonist inhibition than the hormone-induced Ca2+ transient, the sustained accumulation of inositol monophosphates, or colony formation in soft agarose. These data demonstrated inhibition of transmembrane signals associated with autocrine growth control in SCLC by a novel peptide receptor antagonist.
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PMID:A novel bombesin receptor antagonist inhibits autocrine signals in a small cell lung carcinoma cell line. 284 33

Tissues of 50 small cell lung carcinomas were examined for production of 17 peptide hormones. Only when the concentration of a peptide detected in the tumor was 10 pmol or more per g wet weight, was the peptide considered to be produced by the tumor. The frequency of production of at least one of these peptide hormones was 84%, and that of two or more hormones was 50%. These results indicate that peptide hormone production is a very common phenomenon in small cell lung carcinoma. Of the peptide hormones examined, gastrin-releasing peptide is produced with the highest frequency, suggesting that this peptide could play an important role in small cell lung carcinoma.
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PMID:Peptide hormone production in small cell lung carcinomas with particular reference to gastrin-releasing peptide. 302 32


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