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)

The concept of genetic factors playing a role in the pathogenesis of lung cancer has gained increased attention. The present study was undertaken to reexamine the question of HLA antigen association with carcinoma of the lung. In a study of 90 patients, a significant association occurred between HLA-DR7 and resistance to lung cancer, after accounting for smoking status and sex. HLA class I antigens were also implicated. These results suggest that major histocompatibility complex loci affect carcinoma of the lung.
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PMID:HLA antigens influence resistance to lung carcinoma. 191 91

Small cellular lung carcinoma (SCLC) cell lines are susceptible to lysis by NK cells. SCLC, normally negative for MHC class I Ag, were rendered positive for HLA-A and -B Ag by two methods: treatment with IFN-gamma or transfection with HLA class I genes. Exposure to IFN-gamma induced high levels of class I Ag and reduced susceptibility to NK-mediated lysis. However, transfection with either HLA-A2, HLA-B27, or HLA-B27 with beta 2m did not result in reduced susceptibility to NK cells. These transfectants expressed amounts of HLA class I Ag comparable to those in IFN-gamma-treated, untransfected cells. Transfection with the beta 2m gene or plasmid alone neither influenced levels of surface class I Ag nor resulted in reduced susceptibility to lysis by NK cells. Thus, the effects of IFN-gamma on NK susceptibility can be dissociated from the induction of class I Ag.
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PMID:Lack of correlation between levels of MHC class I antigen and susceptibility to lysis of small cellular lung carcinoma (SCLC) by natural killer cells. 254 Dec 6

The frequencies of HLA class I and II antigens and TNF-beta polymorphism in lung cancer patients were investigated in two areas with different immunogenetic backgrounds, in Okinawa and in mainland Japan (Honshu). In Okinawa frequencies of HLA-Cw3 in squamous cell lung carcinoma patients were higher and those of HLA-DR, both in all lung cancer and in adeno lung carcinoma patients, were lower compared to those of normal controls. Among serologic HLA-DR4-positive individuals, no difference of DRB1*04 gene allele frequency was shown between patients and controls. In Honshu no statistically significant difference of HLA-class I and II alleles frequencies was found; however, the frequency of TNF-beta 10.5-kb homozygote in lung cancer patients was lower than that of controls. For 2-year survival, there was no difference between DR4-positive and -negative individuals and also between each TNF-beta type in Okinawa. In contrast, Honshu patients with 10.5-kb homozygote showed an improved 5-year survival ratio compared to those with heterozygote. We postulate that different immunogenetic backgrounds or environments might have caused the varying HLA or TNF-beta association in the predisposition to or prognosis of lung cancer.
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PMID:HLA and tumor necrosis factor beta gene polymorphisms in Okinawa lung cancer patients: comparative study with mainland Japan lung cancer patients. 759 76

HLA class I antigens of the human major histocompatibility complex play an important role in immune response. These molecules present foreign antigenic peptides to cytotoxic T lymphocytes and thereby play a role in the immune surveillance of cells infected with virus or other intracellular pathogens or altered by malignant transformation. A marked deficiency or lack of expression of these antigens has been reported in a variety of human neoplasms. In the present study, we examined the expression of class I alpha chain, beta 2-microglobulin, TAP (TAP1 and TAP2) and LMP (LMP2 and LMP7) genes in a number of human tumor cell lines including small-cell lung carcinoma, hepatocellular carcinoma, colon adenocarcinoma and basophilic leukaemia. These cell lines were deficient in expression of both class I alpha chain and beta 2-microglobulin gene products. In addition, these cell lines lacked the products of MHC-encoded proteasome subunit LMP2 as well as the putative peptide transporter TAP1 genes. In contrast, TAP2 and LMP7 genes were expressed in these cell lines. Treatment of cells with gamma-IFN markedly enhanced the expression of class I alpha chain, beta 2-microglobulin, TAP1 and LMP2 genes with a concomitant increase in cell-surface expression of class I molecules. The upregulation of TAP1 and LMP2 expression is associated with increased class I expression, suggesting that endogenous antigens, e.g. tumor antigens, could be presented by class I molecules following treatment of tumor cells with gamma-IFN.
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PMID:Markedly decreased expression of TAP1 and LMP2 genes in HLA class I-deficient human tumor cell lines. 880 12

HLA class I molecules present antigenic peptides to cytotoxic T lymphocytes and thus play an important role in immune surveillance of cells infected with virus or altered by malignant transformation. Immunochemical studies have demonstrated a marked deficiency or lack of expression of class I molecules on the surface of many different types of tumor cells. It is likely that this allows these cells to escape immune surveillance. In the present study, we examined the molecular basis for lack of expression of class I antigens in small-cell lung carcinoma cell lines. Our results demonstrate that these cell lines also lacked products of MHC-encoded proteasome subunit LMP2 and the putative peptide transporter TAP1. In contrast, LMP7 and TAP2 genes were expressed in these cell lines. Pulse-chase experiments showed that class I molecules were unstable and thus not transported to the cell surface from endoplasmic reticulum. Our results suggest that antigenic peptides were not available for binding to class I alpha chains due to lack of TAP1 and LMP2 gene products. Investigations of the regulatory mechanisms of TAP1 and LMP2 genes showed that the tumor cells lacked trans -regulatory nuclear protein(s), which binds to the interferon-gamma (IFN-gamma) response element (ISRE) in the TAP1, LMP2 bidirectional intergenic promoter. Treatment of tumor cells with IFN-gamma induced ISRE-binding nuclear protein(s) and resulted in expression of TAP1 and LMP2 genes with a concomitant increase in cell-surface expression of class I molecules. Our data provide credence for a role of TAP and LMP genes in immune response.
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PMID:Molecular basis for lack of expression of HLA class I antigens in human small-cell lung carcinoma cell lines. 893 46

HLA class I antigens of the human major histocompatibility complex (MHC) play an important role in immune response. Consistent with their role in immune surveillance, these antigens are expressed on most cell types. However, a marked deficiency or lack of expression of these antigens has been observed in a variety of human neoplasms. We have shown that a number of class I-deficient human tumor cell lines, including small-cell lung carcinoma, lacked products of MHC-encoded TAP1 and LMP2 genes. Since a direct evidence for the role of these genes in class I expression in tumor cells is not available, in the present study we transfected class I-deficient human small-cell lung carcinoma cells with cDNAs corresponding to TAP1 gene and to LMP2 gene. Following transfection, tumor cells expressed products of the respective transfected gene. Cell-surface expression of class I molecules was, however, observed in cells transfected with TAP1, but not in tumor cells transfected with LMP2 gene. Our results provide conclusive evidence for a role of TAP1 gene in class I expression and suggest that transfection of TAP genes may be useful to upregulate class I expression in tumor cells. This strategy for restoration of class I expression by transfection of TAP genes is relevant for tumor rejection and/or abrogation of metastases formation.
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PMID:Transfection of TAP 1 gene restores HLA class I expression in human small-cell lung carcinoma. 942 98

Melanoma tumor antigens, MAGE-1 and -3 are presented on HLA-A1 and -Cw*1601, or -A1 and -A2, respectively, to the corresponding cytotoxic T lymphocytes (CTL). If CTL recognizing these antigens were generated in patients, clones of positive tumor cells should be eliminated. To ascertain whether such an immunological response is active in patients with lung cancer and to determine what fraction of lung cancer patients are candidates for MAGE oriented immunotherapy, we assessed the relationship between HLA-A1 or -A2 expression and MAGE-1 or -3 gene expression in their tumors. MAGE-1 and -3 were detected in 18/55 (33%) and 23/55 (42%), respectively, by reverse transcriptase (RT)-polymerase chain reaction (PCR). Allele specific PCR revealed HLA-A1 and -A2 alleles to be expressed in 0/55 (0%) and 22/55 (40%) of our cohort, respectively. Among the 22 patients with HLA-A2 genotype, expression of HLA class I antigens detectable by immunohistochemistry was lost in five (23%) cases. The frequency of MAGE-3 expression in HLA-A2 patients was 5/17 (29%), somewhat lower than that of patients without HLA-A2 expression, 18/38 (47%), although the difference was not statistically significant (P = 0.17). Neither was there a significant association between HLA-A2/MAGE-3 co-expression and survival (P = 0.15, logrank test). We conclude that there is no clear evidence for elimination of lung cancers co-expressing HLA-A2 and MAGE-3 in vivo. Approximately 10% (5/55) of Japanese lung cancer patients are potential candidates for MAGE-3-based immunotherapy.
Lung Cancer 1998 May
PMID:Frequency of MAGE-3 gene expression in HLA-A2 positive patients with non-small cell lung cancer. 971 30

We derived lung carcinoma cell lines from tumor material resected from a patient with small-cell lung cancer (SCLC) and from a patient with non-small-cell lung cancer (NSCLC). The patient with NSCLC was vaccinated with irradiated autologous tumor cells. The two patients enjoyed an exceptionally favorable clinical evolution and are currently without signs of cancer 10 and 8 yr after their diagnoses, respectively. Autologous mixed lymphocyte-tumor cell cultures (MLTC) were produced with blood lymphocytes stimulated with irradiated autologous tumor cells. The first patient's SCLC cells, which carried a small amount of human leukocyte antigen (HLA) class I molecules, were incubated with interferon-gamma (IFN-gamma) before being used as stimulator cells. A cytolytic T-lymphocyte (CTL) clone was derived that specifically lysed the IFN-gamma-treated SCLC cells but did not lyse untreated tumor cells or autologous lymphoblasts. Clones of autologous tumor-specific CTL, directed against the NSCLC cells of the other patient, were also obtained. These tumor cells carried a higher level of HLA class I molecules and were lysed by the CTL without incubation with IFN-gamma. Altogether, these results indicate that SCLC and NSCLC cancer cells can be recognized by autologous CTL, and might therefore be susceptible to specific immunotherapy.
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PMID:Derivation of tumor-specific cytolytic T-cell clones from two lung cancer patients with long survival. 987 18

We identified a novel 8.1-kb human melanoma gene, MG50, derived from subtractive hybridization with a squamous lung carcinoma cell line, LU-1. 6.8 kb containing an open reading frame were sequenced, and the structure of the encoded 1496 amino acid protein was deduced. With HLA-A2.1-transduced Drosophila cells as antigen-presenting cells, we identified six epitopes restricted by HLA-A2.1 that elicited CTLs in vitro. Reactivity of the CTLs to melanoma cells containing MG50 indicated that the epitopes were displayed naturally. Significant cross-reactivity of CTLs immunized against a melanoma cell line that lacked HLA-A2.1 indicated that at least four of the epitopes were also recognized in a different HLA class I context, most likely HLA-A*6802. By quantitative reverse transcription, MG50 message was found in one of two skin melanoma cell lines, an ocular melanoma cell line, two of four metastatic skin melanomas, two of three mammary carcinomas, one of two colon carcinomas, and an ovarian carcinoma. Of six normal tissues, MG50 was found only in a specimen of normal skin and was absent from a congenital nevus. It is likely that MG50 is the gene for the interleukin 1 receptor antagonist because a reported sequence of cDNA from the latter had a sequence of 528 bases in the 3' region, a long contiguous base sequence, and 176 encoded amino acids identical with those of MG50. MG50 is one of the few melanoma-associated antigens that is not a differentiation antigen or a mutated protein. Because of its nature, it may prove to be important in the pathogenesis of the tumors in which it is found, as well as an immunogen and target for immunotherapy.
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PMID:A novel melanoma gene (MG50) encoding the interleukin 1 receptor antagonist and six epitopes recognized by human cytolytic T lymphocytes. 1110 12

Human tumor cells frequently exhibit abnormalities in the major histocompatibility complex (MHC) class I surface expression which can be due to structural alterations and/or dysregulation of various components of the MHC class I antigen processing machinery, such as HLA class I heavy and light chains, the peptide transporter and the proteasome subunits. Although several cofactors critical for proper MHC class I assembly have been identified, their contribution to the immune escape phenotype of tumor cells has not been analyzed. In order to determine whether tapasin deficits are an integral part of immune escape mechanisms of human tumors, we studied the constitutive and cytokine-regulated expression pattern of tapasin in malignant cells of distinct histology. Heterogeneous and reduced expression levels of tapasin were found in small-cell lung carcinoma, pancreatic carcinoma, colon carcinoma, head an neck squamous cell carcinoma and renal cell carcinoma cell lines. Tapasin downregulation was also prominent in surgically removed tumor lesions when compared to normal controls. The impaired tapasin expression is often associated with low MHC class I cell surface expression. In addition, various cytokines, including interferon (IFN)-alpha, IFN-gamma, tumor necrosis factor (TNF)-alpha and interleukin (IL)-4, but not granulocyte-macrophage colony stimulating factor (GM-CSF), transcriptionally upregulate to a distinct extent and in a time-dependent manner tapasin expression in tumor cells. Thus, deficient tapasin expression appears to be a frequent event in human tumor cells. Its restoration by cytokines further suggests that impaired tapasin expression in tumors is rather due to dysregulation than to structural alterations.
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PMID:Downregulation of the constitutive tapasin expression in human tumor cells of distinct origin and its transcriptional upregulation by cytokines. 1116 57


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