Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0149925 (small cell lung cancer)
 6,491 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The clinical importance of ras oncogene product p21 was evaluated in surgically treated non-small cell lung cancer patients. Paraffin sections of tumors were analysed immunohistochemically using anti-ras p21 monoclonal antibody rp35. The ras p21 expression was correlated with clinicopathological parameters and survival. Survival analysis demonstrated significantly longer survival times in patients with p21-negative tumors than those with p21-positive tumors. In Cox's multivariate analysis, ras p21 expression was a major and independent prognostic determinant of survival. On the other hand, in small cell lung cancer, L-myc gene is known to be frequently amplified and overexpressed. Immunoprecipitation analysis of two small cell lung cancer cell lines (classic type) revealed three major L-myc proteins (p60, p66 and p68), all of which were derived from extensive phosphorylation of a p59 protein. Expression and phosphorylation of L-myc protein, as well as the autocrine growth mechanism of gastrin-releasing peptide (GRP), is thought to be involved in the malignant behavior of small cell lung cancer.
 ...
PMID:[Clinical significance of oncogene product expression in human lung cancer]. 133 97

The 5-year survival of lung cancer patients is about 30% in Japan. One of the reasons for the poor prognosis seems to be drug resistance. It has been reported that certain types of oncogenes, such as ras, myc and fos, may play an important role in drug resistance. The myc protein forms a sequence-specific DNA-binding complex with Max and may act as a transcription factor; thus, it may be possible that myc family oncogenes are involved in DNA synthesis and repair processes mediating drug resistance. We report here that L-myc oncogene may be involved in the transition from drug-sensitive to drug-resistant phenotype of a certain small cell lung cancer cell line.
 ...
PMID:[Relationship between drug resistance and oncogenes in lung cancer cell lines]. 133 94

Altered and deregulated cellular oncogenes were found in many human solid tumors. Except for a few types of tumors that consistently exhibited specific altered proto-oncogenes, the majority of tumors are associated with a number of transcriptionally activated cellular oncogenes. In the heterologous group of non-small-cell lung cancer (NSCLC), nothing about a specific pattern of proto-oncogene expression is known. Therefore, we investigated the expression of a panel of cellular oncogenes in NSCLC cell lines. DNA and RNA from 11 established NSCLC cell lines (4 adenocarcinoma cell lines, 3 squamous cell carcinoma cell lines, 3 large-cell carcinoma cell lines and 1 mesothelioma cell line) were isolated and analysed using the Southern, dot blot and Northern hybridization technique. c-myc RNA expression was found in all NSCLC cell line, L-myc expression only in 1 adenocarcinoma cell line, N-myc and c-myb expression in none of the 11 cell lines examined. No c-myc amplification could be detected in the DNAs. v-sis-related mRNA was observed in 5/11 cell lines without association to a specific NSCLC subtype. v-src-related mRNA, found in all tested cells, exhibited increased levels in 1 adenocarcinoma cell line (A-549) compared to the other cell lines. Binding sites for epidermal growth factor (EGF) had been described previously in NSCL, therefore we found erbB homologue transcripts coding for the EGF receptor in all NSCLC cell lines. Also, c-raf1-, N-ras-, Ki-ras-, and H-ras-related RNA expression was observed in all lines. We conclude that L-myc, N-myc, and c-myb expression does occur less frequently in NSCLC than in SCLC. Also amplification does not appear to be an important mechanism by which the c-myc proto-oncogene is activated in NSCLC. A specific pattern of oncogene expression could not be detected in NSCLC cells; each cell line examined showed its own pattern. However, transcriptional activation of a proto-oncogene like erbB, ras, raf, src, and c-myc, which are all involved in the progression pathway of EGF, may be a common feature of NSCLC.
 ...
PMID:Different pattern of expression of cellular oncogenes in human non-small-cell lung cancer cell lines. 169 Feb 10

Despite disappointing results in the treatment of small cell lung cancer (SCLC), major progress in our understanding of SCLC biology has occurred in the past decade. Advances in the technique for culturing SCLC tumours in vitro have greatly facilitated the study of the biological properties of this tumour. The major progress in our understanding of SCLC includes: 1) the availability of nonspecific biological tumour markers such as neuron-specific enolase (NSE), the BB isoenzyme of creatine phosphokinase (CPKBB), bombesin/gastrin releasing peptide (GRP) and chromogranin A; 2) the generation of monoclonal antibodies raised against the neural and epithelial features of SCLC tumours; 3) the identification of several autocrine growth factors such as bombesin/GRP, insulin-like growth factor (IGF), transferrin and physalaemin; 4) the close study of cytogenetic abnormalities leading to the discovery of a unique chromosomal deletion of the short arm of chromosome 3 (del 3p 14-21), and to changes in oncogenic expression, e.g. c-myc, L-myc and N-myc, accounting for known biological and treatment results. These data suggest that all lung cancers arise from a common stem cell of endodermal origin. The information derived from these biological studies represents the most promising avenue towards new treatment strategies in SCLC.
 ...
PMID:Biology of small cell lung cancer: an overview. 216 19

The expression of myc-related genes (c-myc, N-myc, and L-myc) in small cell lung cancer (SCLC) was studied by RNA-RNA tissue in situ hybridization. The tissues investigated included cytospins of ten cell lines derived from patients with SCLC, four corresponding nude mouse xenografts from cell lines, and metastatic tumor tissue obtained by surgical biopsy and at autopsy. The probes were prepared as 35S labeled complementary RNA. The expression of each gene was demonstrated specifically by autoradiography in the cytoplasm of the neoplastic cell samples. The average levels of oncogene expression in each specimen corroborated previous data obtained by Northern blot assays. In addition, heterogeneity in gene expression from cell to cell in each sample was noted. This study represents the first attempt to demonstrate oncogene expression in lung cancer cell lines and tissues in situ, and confirms that the expression of these myc related genes can be seen in the primary tumor. The technique of RNA-RNA tissue in situ hybridization has great potential in answering fundamental questions of tumor cell heterogeneity and progression in SCLC. It should be useful in both prospective and retrospective studies.
 ...
PMID:A study of myc-related gene expression in small cell lung cancer by in situ hybridization. 245 19

Bombesin is a 14 amino acid peptide originally isolated from amphibian skin; its mammalian homolog is gastrin-releasing peptide (GRP). GRP is found in a high proportion of human small cell lung cancer (SCLC) cell lines. [Tyr4]bombesin caused an increase in intracellular Ca2+ ([Ca2+]i) in 5/11 SCLC cell lines tested. Bombesin action was not inhibited by agents known to alter the plasma membrane potential, nor did replacement of external Na+ with choline affect the bombesin-induced signal. [Tyr4]bombesin did not itself affect the membrane potential. Chelation of external Ca2+ reduced but did not prevent the bombesin-evoked increase in [Ca2+]i. This suggested that in SCLC, bombesin congeners not only promote an influx of extracellular Ca2+ but also release Ca2+ from intracellular stores. [Tyr4]bombesin increased levels of inositol 1,4,5-trisphosphate within seconds of addition to SCLC cell cultures and enhanced the accumulation of inositol 1-phosphate and inositol 4-phosphate in the presence of Li+. The SCLC cell lines responsive to bombesin constitutively expressed L-myc and did not express c-myc or N-myc. In contrast, SCLC cells non-responsive to bombesin had prominent constitutive expression of c-myc or N-myc with or without L-myc expression. Responding cell lines also had constitutive expression of the preproGRP gene, while non-responding cell lines showed no evidence of GRP gene expression. These data support the concept that SCLC which constitutively express the GRP gene and L-myc but not c-myc or N-myc can be stimulated in an autocrine fashion by GRP or its congeners to increase [Ca2+]i by a pathway involving phosphatidylinositol turnover.
 ...
PMID:A correlation of bombesin-responsiveness with myc-family gene expression in small cell lung carcinoma cell lines. 246 98

In this study 12 small cell lung cancer cell lines were tested for amplification of myc oncogenes, the location of amplified sequences, and the possible correlation between number of dmin and degree of amplification in dmin-containing lines. C-myc appeared to be amplified in four cell lines, and N-myc amplification was detected in two cell lines. No amplification of L-myc was found. The degree of amplification in the different cell lines varied between 20X and 100X. The cell lines with myc amplification appeared to contain numerous dmin, although in one cell line they occurred in only 10% of the cells. The other cells in this line contained a homogeneously staining region (HSR). In situ hybridization was carried out to find the location of the amplification. In four cell llines the amplified myc genes were found to be located on the dmin. In the cell line with the HSR in most cells and dmin in a minority of its cells, amplification was found both at the HSR and on the dmin. In one cell line the myc sequences seemed to be dispersed through the genome. The ratio between the average number of dmin per cell and the degree of amplification did not vary considerably between the cell lines, with one exception. In that cell line the number of dmin exceeded the number of myc sequences by about one order of magnitude. Apparently, the population of dmin in this cell was heterogeneous and amplified myc genes were only present on a subpopulation.
 ...
PMID:Localization of amplified c-myc and n-myc in small cell lung cancer cell lines. 254 Aug 98

Eighteen small cell lung cancer (SCLC) lines (including nine lines established by this group) as well as 31 tumor samples from 23 SCLC patients were examined for the surface antigen phenotype and the expression and amplification of the myc gene family. The expression of NE-150 neuroendocrine, PE-35 panepithelial and OE-130 epithelial antigens corresponded well with the level of biomarkers of SCLC lines, i.e., the NE-150+/PE-35+/OE-130- phenotype corresponded to classic type, while the other phenotypes such as NE-150+/PE-35-/OE-130- to variant type. In tumor specimens, most classic SCLC (consisting of oat cell type and intermediate cell type, subtype a) showed NE-150+/PE-35+/OE-130- phenotype, while small cell-large cell carcinoma (intermediate cell type, subtype b) expressed various phenotypes. The amplification of the myc gene family was observed in nine out of 18 lines (50%) and five out of 23 patient tumors (22%). Higher levels of expression of either c-myc, N-myc, or L-myc were detected in 16 out of 18 lines (89%) and in five out of six patient tumors (83%), when compared with that of normal or fetal lung tissues. Thus, the higher expression without obvious myc gene amplification was observed. The cell lines and tumors with the amplified myc always expressed their corresponding myc genes. The results suggested that higher levels of expression of the myc gene family may play a significant role in the oncogenesis of SCLC. Amplification and/or high levels of expression of c-myc were observed not only in variant type SCLC lines, but also in classic type lines. Thus, they were not necessarily associated with distinct biomarkers of SCLC lines.
 ...
PMID:Expression and amplification of myc gene family in small cell lung cancer and its relation to biological characteristics. 254 Sep 5

We have examined post-translational modification of the L-myc protein using polyclonal and monoclonal antibodies against a peptide well conserved in the predicted amino acid sequences of the c-myc, N-myc and L-myc genes. These antibodies precipitate three polypeptides of Mr 60-66,000 from [35S]methionine or [32P]orthophosphate-labelled human small cell lung cancer cell lines expressing amplified L-myc genes, but not the other myc genes. Treatment of the L-myc immunoprecipitates with alkaline phosphatase prior to electrophoresis converts the three methionine-labelled polypeptides into a single band migrating at Mr 59,000, and efficiently removes radioactivity from the 32P-labelled L-myc protein, suggesting that, in contrast to the c-myc and N-myc proteins, the L-myc polypeptide heterogeneity is due to differential phosphorylation of a common precursor. When the phorbol ester 12-O-tetradecanoyl-phorbol-13-acetate (TPA) or serum is added to cultures of U-1690 cells the Mr 66,000 polypeptide is rapidly enriched while the Mr 60,000 form is decreased in the L-myc immunoprecipitates. This effect is correlated with the ability of phorbol ester and diacylglycerol analogues to activate protein kinase C. The TPA-induced phosphorylation of the L-myc protein occurs in a protein synthesis-independent manner as it is not inhibited by cycloheximide or anisomycin. These data indicate that the phosphorylation of the L-myc nuclear oncoprotein is modulated in response to TPA via a rapid signal transduction system involving protein kinase C. This mechanism could play an important role in the response of lung cells to e.g. bombesin-related growth factors.
 ...
PMID:Rapid phosphorylation of the L-myc protein induced by phorbol ester tumor promoters and serum. 254 Sep 55

While the ability of the retroviral oncogene V-jun to transform chicken cells led to its discovery, the oncogenic potential of its cellular homologue, c-jun, which encodes a transcription factor, is unknown. We isolated a 1070-base-pair cDNA clone containing the unmutated entire open reading frame of c-jun from a human small cell lung cancer line. This cDNA as well as a 5.6-kilobase normal human genomic DNA fragment containing the c-jun gene were placed under the control of retroviral long terminal repeats and introduced into primary rat embryo cells (RECs), with or without other oncogenes, and into an immortal rat fibroblast cell line, Rat-1a, as a single gene. In Rat-1a cells the expression of human c-jun mRNA was associated with the ability to clone in soft agarose and form tumors in nude mice. When the c-jun cDNA or genomic DNA constructs were introduced into RECs, no foci of transformed cells were seen with c-jun alone or c-jun cotransfected with deregulated c-myc or L-myc protooncogenes. However, cotransfection of the c-jun constructs with an activated human c-Ha-ras gene led to foci of transformed cells which gave rise to immortalized cell lines that cloned in soft agarose and formed tumors in nude mice. Furthermore, formation of foci of transformed RECs by the c-jun/ras combination was augmented 3-fold by the tumor promoter phorbol 12-tetradecanoate 13-acetate. We conclude that deregulated expression of human c-jun can participate in malignant transformation of normal mammalian cells.
 ...
PMID:Deregulated expression of human c-jun transforms primary rat embryo cells in cooperation with an activated c-Ha-ras gene and transforms rat-1a cells as a single gene. 264 96


1 2 3 4 Next >>