Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0677930 (primary tumor)
 20,210 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Human leukocyte antigen (HLA) classes I and II molecules are essential for antigen presentation to cytotoxic T cells and helper T cells, respectively. Consequently, they may play a role in anticancer immunotherapy as well. We studied whether the pretreatment HLA phenotype of the tumor is predictive for response to interferon immunotherapy in vivo. Therefore, renal cell carcinoma (RCC) primary tumor lesions from 31 patients treated with interferon-alpha and interferon-gamma (13 responders and 18 nonresponders) were analyzed retrospectively for HLA antigen expression with immunohistochemical methods. Furthermore, from eight patients, pretreatment metastatic lesions were examined. In the primary tumors HLA class I expression was high: in 26 of 30 lesions more than 50% cells were stained. HLA class II expression was mostly low: in 14 of 31 primary tumors less than 5% cells were stained. A significant correlation was found between HLA phenotype of primary tumors and corresponding metastases. There was no association between tumor HLA classes I and II antigen expression and clinical response to interferon therapy. In conclusion, pretreatment HLA phenotype of RCC has no predictive value for outcome of interferon immunotherapy. A role for treatment-induced changes in HLA expression in vivo, however, can not be excluded. These findings do not provide indications for the working mechanism of interferon immunotherapy in vivo.
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PMID:Human leukocyte antigen expression in renal cell carcinoma lesions does not predict the response to interferon therapy. 163 84

MHC class I and II molecules play an important role in specific interactions with cells of the immune system. Endogenous or exogenous antigens are presented to the clonotypic receptor of T cells as small peptides associated to MHC molecules. Qualitative or quantitative variation in the expression of these molecules in the surface of tumor cells could have important implications in anti-tumor immune responses. We have analysed 344 human tumors for HLA class I and II expression and found that 10-30% of tumors present a total loss of HLA ABC molecules. In addition, HLA-A or -B locus-specific losses were also detected. These alterations have been correlated with tumor aggressiveness in breast and laryngeal carcinomas. We also have observed that the expression of HLA ABC molecules in autologous metastasis did not always correspond with the expression detected in the primary tumor. In laryngeal carcinomas HLA-DR expression was associated with an excellent prognosis. We have observed in most tumors that the absence of class I molecules usually corresponds with a simultaneous loss of heavy chain and beta 2 microglobulin expression and with a low level of the mRNA specific for class I genes. Nevertheless, a variety of mechanisms are involved since in colon tumors the absence of expression is caused by beta 2 microglobulin down regulation. Also post-transcriptional mechanisms may be involved in the differential expression of HLA-A and -B locus products. There is no doubt that a more exact knowledge of the mechanisms that produce alteration in the expression of these antigens will help to manipulate MHC gene expression in human tumors and to induce a more efficient immune response.
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PMID:MHC expression on human tumors--its relevance for local tumor growth and metastasis. 191 16

The expression of monomorphic determinants of the histocompatibility leukocyte antigens (HLA) class I antigens by human malignant tumor cells was studied in tissue specimens of 70 primary tumor lesions obtained from patients with carcinoma of the breast (41 patients), colon (8 patients), urinary bladder (8 patients), and kidney (13 patients), and in samples of either synchronous or metachronous lymph node, lung, or liver metastases available in 44 of the patients. The frequencies of HLA class I expressor and nonexpressor tumor cells were determined by immunohistochemical staining of histological sections of fresh frozen tissue samples with the W6/32 monoclonal antibody. The tumor cell populations in the majority of the primary lesions consisted predominantly of HLA-immunoreactive cells (observed in 38 of 70 patients; 54%), especially in those patients who did not have clinical evidence of metastatic disease (8 of 11 patients; 73%). Various degrees of loss of reactivity were observed in other primary lesions, although in only 8 (12%) tumors (7 of which were obtained from patients with metastatic disease), the neoplastic cells were nearly exclusively HLA-nonreactive. In contrast, the majority of metastatic lesions consisted of either predominantly HLA-negative cells (33 of 44 specimens; 75%) or mixed populations (10 of 44 specimens; 23%), whereas only one metastatic lesion manifested HLA class I antigen staining in more than 70% of its tumor cells (P = 0.0005). Intravascular clusters of tumor cells consisted predominantly of HLA class I nonexpressors. The observed patterns of distribution of HLA expressors and nonexpressor tumor cells are compatible with the notion that HLA-negative cells in human carcinomas manifest a selective advantage with regard to metastatic progression and growth. The suppressed expression of major histocompatibility complex class I antigens on metastatic cells may lead to failure of presentation of cell surface tumor specific epitopes to host cytotoxic T-lymphocytes. Such a process would enable tumor cells to evade host immune responses and would promote and enhance cell dissemination and metastatic growth.
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PMID:Expression of HLA-A,B,C antigens on primary and metastatic tumor cell populations of human carcinomas. 193

Clinical effects and side effects were studied in the adoptive immunotherapy of patients bearing malignant diseases using human leukocyte antigen (HLA)-mismatched allogeneic lymphokine-activated killer (LAK) cells. Allogeneic LAK cells were induced from peripheral blood lymphocytes (PBL) of normal donors by means of initial stimulation with pokeweed mitogen (PWM). Six of 15 patients applied in the adoptive immunotherapy showed clinical effects such as partial or complete regression of pulmonary metastasis, pleural effusion and primary tumor. All pulmonary metastatic lesions were eliminated in one case by this adoptive immunotherapy combined with chemotherapy. Generally toxic effects were chillness, fever and general fatigue which were reversible, and no allergic side effects occurred even though allogeneic LAK cells were injected frequently except one patient who showed preshock like symptom accompanied with leukocytopenia and continuous hypotension immediately after infusion but was finally rescued. In the patients who received more than 10(11) of allogeneic LAK cells, anti-HLA class I antibodies appeared without any evidence of autoantibody. However, immunological side effects were never experienced after injection of allogeneic LAK cells even when the anti-HLA class I antibodies appeared in the patients. Taken together, allogeneic LAK cells could be considered as alternative therapy for patients with malignancies who could not supply sufficient materials of autologous LAK cells.
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PMID:Use of human leukocyte antigen-mismatched allogeneic lymphokine-activated killer cells and interleukin-2 in the adoptive immunotherapy of patients with malignancies. 754 80

The altered expression of histocompatibility leukocyte antigens (HLA) in the development to cervical carcinoma suggests that tumor progression may be related to impaired recognition by host immune defense mechanisms. To investigate whether this phenomenon plays a role in the process of metastasis of cervical cancer, we analyzed and compared the HLA expression with the number of infiltrating immune cells in primary cervical carcinoma and related autologous metastases (n = 30) by staining serial paraffin and corresponding frozen sections with a panel of monoclonal antibodies. In 60% of the cervical metastases, compared to 21% of the primary tumors, a downregulation of monomorphic HLA class I antigens was observed, with frequent allele-specific alterations. In 50% the HLA class II expression was slightly increased on the metastatic tumor cells in comparison to the primary tumor. In addition, variability of alterations in HLA expression was observed between different metastases in the same patient. A minor infiltration of immune cells was present in cervical metastases compared to the primary tumors, especially in the HLA class I-downregulated metastases. Furthermore, loss of HLA class I expression on the metastatic tumor cells resulted in a significant decrease of tumor-infiltrating CD8+ T lymphocytes. These findings suggest that in cervical carcinoma loss of HLA class I expression plays a decisive role in the escape from immune surveillance leading to a greater metastatic potential of tumor cells.
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PMID:Altered HLA expression by metastatic cervical carcinoma cells as a factor in impaired immune surveillance. 777 40

We determined the frequency of expression of the major histocompatibility complex antigens HLA-A,B,C in tumor cells from 207 primary tumor lesions of breast and bronchogenic carcinomas, to see if the expression of theses antigens was linked with several clinicopathological parameters associated with tumor aggressivity, such as abnormal cellular DNA content. We compared tumor tissues with nonneoplastic tissues and tissues from 15 benign breast lesions. HLA class I expressor and nonexpressor tumor cells were determined by using immunohistochemical stains (PAP and APAAP methods) and antibodies against these antigens. Reduction of HLA class I antigen was detected in 65 tumors (31.7%) and was significantly associated with poor tumor differentiation and abnormal cellular DNA content (p < 0.001). These characteristics might define a group of aggressive tumors in which the decrease of HLA class I antigens would enable tumor cells to avoid eliciting host immune responses. On the other hand, the altered regulatory mechanisms, of tumors with abnormal cellular DNA content, might modulate the expression of HLA class I molecules.
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PMID:Class I major histocompatibility complex antigens and tumor ploidy in breast and bronchogenic carcinomas. 904 59

It is generally accepted that human and experimental tumor cells can lose major histocompatibility complex (MHC) class I molecules. These human leukocyte antigen (HLA) losses are detected when the primary tumor breaks the basal membrane, invades the surrounding tissues, and starts to metastasize. These altered HLA class I phenotypes probably constitute the major tumor escape mechanism facing anti-tumor T-cell mediated responses. Thus, it is important to characterize these phenotypes in clinical tumor samples, analyze the mechanism(s) responsible for them, and counsel patients before and during peptide anti-cancer immunotherapy. The present paper summarizes the most relevant altered HLA class I phenotypes found in human tumor samples, indicates their frequency, and outlines the mechanisms implicated. This review also points out that the natural killer (NK) escape mechanism of HLA class I deficient cancer cells is yet to be defined. Knowledge accumulated to date reveals that HLA class I molecules are an important crossroad in tumor immunology.
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PMID:The HLA crossroad in tumor immunology. 1065 79

The expression of human leukocyte antigen (HLA) class I molecules on the cell surface is necessary for the presentation of peptide antigens to cytotoxic CD8+ T lymphocytes of the immune system. Down-regulation of HLA class I gene expression has been implicated in tumorigenesis, including squamous cell carcinoma of the head and neck (SCCHN). Loss of MHC class I antigens may be one mechanism by which tumor cells escape immune detection. We performed prospective immunostaining of 26 primary SCCHN tumors and samples of normal mucosa harvested several centimeters away from the primary tumor, using a large panel of antibodies directed against allele-specific as well as monomorphic determinants of HLA class I molecules. Loss of expression of HLA class I proteins in the tumor was found in 50% (13 of 26) of primary tumors and was highly correlated with HLA loss in the corresponding normal mucosa (P < 0.0001). Further analysis demonstrated that the loss of HLA class I expression in the tumor was significantly associated with regional lymph node metastases (nodal stage; P = 0.0388), and that the number of HLA class I alleles lost in the normal mucosa was associated with subsequent development of a new primary aerodigestive tract cancer (P = 0.042). A patient with two metachronous cancers available for analysis had no evidence of HLA loss in the first tumor, demonstrated allelic loss in the second cancer, and subsequently died of disease. These results suggest that the loss of expression of HLA class I alleles may have prognostic implications.
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PMID:Human leukocyte antigen class I allelic and haplotype loss in squamous cell carcinoma of the head and neck: clinical and immunogenetic consequences. 1091 26

We characterized the HLA class I alterations in five metastases obtained from two patients with melanoma immunized with Melan A/MART-1, tyrosinase and gp100 tumor peptides. All three metastases analyzed in the first patient (NW145) showed a similar HLA class I alteration with a dual population of melanoma cells. One population was HLA class I antigen positive and the other had loss of heterozygosity (LOH) in the short arm of chromosome 6 leading to an HLA haplotype loss (A02011, B4007, Cw1). The absence of HLA-A2 antigen may explain why this patient did not develop HLA-A2 restricted, Melan A/MART-1 specificity immunization, since this HLA molecule is the restriction element for the tumor peptides used. However, this HLA-deficient population was not selected after peptide immunotherapy. The primary tumor in this patient presented LOH in region 6q, but only in the vertical growth phase of the lesion, whereas LOH at 6p was observed only in DNA from metastatic material. The second patient (NW16) also presented two metastatic lesions with an identical HLA molecular defect, i.e. HLA B locus downregulation (HLA B51011: serological B51; B1503: serological B70). One lesion expressed the tumor antigen (Melan A/ MART-1), but the other did not. Interestingly, the antigen-positive metastasis regressed after peptide immunotherapy, whereas the other progressed rapidly. These findings provide the first indication that multiple metastases generated in the same host can have identically altered HLA class I phenotypes.
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PMID:Analysis of HLA class I expression in different metastases from two melanoma patients undergoing peptide immunotherapy. 1155 81

Immunotherapy targeting for the induction of a T-cell-mediated antitumor response in patients with renal cell carcinoma (RCC) appears to hold significant promise. Here we describe a novel RCC vaccine strategy that allows for the concomitant delivery of dual immune activators: G250, a widely expressed RCC associated antigen; and granulocyte/macrophage-colony stimulating factor (GM-CSF), an immunomodulatory factor for antigen-presenting cells. The G250-GM-CSF fusion gene was constructed and expressed in Sf9 cells using a baculovirus expression vector system. The Mr 66,000 fusion protein (FP) was subsequently purified through a 6xHis-Ni2+-NTA affinity column and SP Sepharose/fast protein liquid chromatography. The purified FP retains GM-CSF bioactivity, which is comparable, on a molar basis, to that of recombinant GM-CSF when tested in a GM-CSF-dependent cell line. When combined with interleukin 4 (IL-4; 1000 units/ml), FP (0.34 microg/ml) induces differentiation of monocytes (CD14+) into dendritic cells (DCs) expressing surface markers characteristic for antigen-presenting cells. Up-regulation of mature DCs (CD83+CD19-; 17% versus 6%) with enhanced expression of HLA class I and class II antigens was detected in FP-cultured DCs as compared with DCs cultured with recombinant GM-CSF. Treatment of peripheral blood mononuclear cells (PBMCs) with FP alone (2.7 microg/10(7) cells) augments both T-cell helper 1 (Th1) and Th2 cytokine mRNA expression (IL-2, IL-4, GM-CSF, IFN-gamma, and tumor necrosis factor-alpha). Comparison of various immune manipulation strategies in parallel, bulk PBMCs treated with FP (0.34 microg/ml) plus IL-4 (1000 units/ml) for 1 week and restimulated weekly with FP plus IL-2 (20 IU/ml) induced maximal growth expansion of active T cells expressing the T-cell receptor and specific anti-RCC cytotoxicity, which could be blocked by the addition of anti-HLA class I, anti-CD3, or anti-CD8 antibodies. In one tested patient, an augmented cytotoxicity against lymph node-derived RCC target was determined as compared with that against primary tumor targets, which corresponded to an 8-fold higher G250 mRNA expression in lymph node tumor as compared with primary tumor. The replacement of FP with recombinant GM-CSF as an immunostimulant completely abrogated the selection of RCC-specific killer cells in peripheral blood mononuclear cell cultures. All FP-modulated peripheral blood mononuclear cell cultures with antitumor activity showed an up-regulated CD3+CD4+ cell population. These results suggest that GM-CSF-G250 FP is a potent immunostimulant with the capacity for activating immunomodulatory DCs and inducing a T-helper cell-supported, G250-targeted, and CD8+-mediated antitumor response. These findings may have important implications for the use of GM-CSF-G250 FP as a tumor vaccine for the treatment of patients with advanced kidney cancer.
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PMID:Induction of G250-targeted and T-cell-mediated antitumor activity against renal cell carcinoma using a chimeric fusion protein consisting of G250 and granulocyte/monocyte-colony stimulating factor. 1169 14


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