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)

A monoclonal antibody (mAb) directed against the cytokeratin (CK) polypeptide no. 18 specifically expressed in cells derived from simple epithelia was used to detect epithelial tumor cells in bone marrow aspirates. Of 156 patients with colorectal carcinoma, 42 presented with cells at the time of primary surgery. The incidence of positive findings varied considerably with the size and the localization of the primary tumor, the involvement of regional lymph nodes, and the presence of clinically manifest metastases. Applying a sensitive double-staining procedure, we could demonstrate that epithelial cells in bone marrow showed a heterogeneic expression of receptors for epidermal growth factor (EGF-R) and transferrin (Tf-R) as well as of the proliferation-associated Ki67 antigen. Also human leukocyte antigen (HLA) class I antigens differed widely in their expression on the CK-positive cells. Clinical follow-up studies on 85 patients showed a significantly higher relapse rate in patients presenting with CK-positive cells in their bone marrow at the time of primary surgery. Twenty-three patients were monitored for the presence or absence of CK-positive cells in bone marrow over time. The majority of monitored patients (18 of 23) exhibited a constant pattern of immunocytochemical findings during the time of observation. Thus, the technique may be useful in identifying high-risk patients as well as in monitoring adjuvant therapeutic trials.
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PMID:Epithelial tumor cells in bone marrow of patients with colorectal cancer: immunocytochemical detection, phenotypic characterization, and prognostic significance. 169 90

Ten different human renal cell carcinoma (RCC) primary tumors were xenografted into BALB/c nu/nu mice. Five of the tumors (NU-10, NU-12, NU-20, NU-22, and NU-28) gave rise to serially transplantable tumors that were further characterized. Histology, DNA index, immunohistochemical characteristics, growth rate, and clonogenic potential were followed from primary tumor to the 5th to 15th transplant passage. Only one of the tumors (NU-20) showed remarkable instability for all tested parameters in the first five transplant passages. Histology of the other tumors was essentially the same to the histology of the primary tumors, although differences between human and host-derived vessels were apparent. DNA index values in general showed a trend toward an aneuploid character of the xenografts. Immunohistochemical analyses showed a loss of intensity of staining but a concomitant rise in the fraction of positively staining cells with antibodies against cytokeratins, vimentin, tumor-associated antigens, and human leukocyte antigen (HLA) class I antigens. Human leukocyte antigen class II antigen expression showed a loss of intensity as well as a decrease in the fraction of positive cells. Tumor doubling time was lowest in transplant passage number 0, and stable growth was noticed in transplant passages 1 through 4. Clonogenic potential of four of the lines was higher for the xenografts than for the primary tumors. The authors conclude that, on xenografting, histologic characteristics of the primary tumor are essentially conserved. Progression in the first transplant passages, however, results in tumors with a more aggressive character.
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PMID:Establishment and characterization of five new human renal tumor xenografts. 173 37

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

Renal cell carcinomas (RCCs) are thought to be immunogenic, because cytokine-induced and even spontaneous tumor regression has been observed in a significant number of patients. However, little is known about the nature of immune responses that might lead to tumor regression. We studied naturally arising human T-cell responses against RCC by combining molecular analyses of T-cell receptor (TCR) usage in primary tumors in situ with functional analyses of tumor-infiltrating lymphocytes (TILs) in vitro. TILs of patient 26 that were cultured in vitro showed a human leukocyte antigen (HLA-A*0201)-restricted cytotoxic activity specific for autologous tumor cells. These tumor-derived lymphocytes were dominated by a family of T cells expressing V alpha20- and V beta22-positive TCRs. Their specificity-conferring third complementarity-determining regions were highly homologous with respect to the loop length and selection of particular amino acids in both TCR chains. These characteristics are similar to those reported for antigen-selected murine T cells recognizing immunodominant epitopes of non-self proteins. To evaluate the biological significance of these CTLs in vivo, we analyzed the corresponding TCR transcripts in the cryopreserved tumor material of patient 26 and in a second HLA-A*0201-positive RCC patient whose tumor cells were also lysed by TIL-26. The in situ TIL populations of both patients used related families of highly homologous TCRs, supporting the contention that immunodominant responses directed against a shared tumor-associated antigen occurred in both individuals in vivo. Furthermore, in the absence of overt metastatic disease, the tumor antigen-specific CTLs of patient 26 were shown to persist in the periphery 4 years after removal of the primary tumor. These results demonstrate that antigen-driven T-cell responses specific for spontaneously arising carcinomas developed in these patients and showed long-term persistence, even in the absence of immunotherapy.
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PMID:Human renal cell carcinoma antigen-specific CTLs: antigen-driven selection and long-term persistence in vivo. 967 74

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

BACKGROUND: Some patients with stage IV gastric cancer have a long survival. Host immune response and proteolytic activity in the primary tumor may be associated with outcome in these patients. The purpose of this study was to assess prognostic factors in patients with stage IV far advanced gastric cancer.METHODS: Findings in 26 patients who underwent resection of stage IV gastric cancer were retrospectively analyzed for clinicopathological variables, and for the immunohistochemical expression of human leukocyte antigen (HLA)-DR as an index of host immune response and for expression of urokinase type-plasminogen activator (u-PA) as an index of proteolytic activity in the tumor.RESULTS: Of the 13 clinicopathological and immunohistochemical variables tested by univariate analysis surgical curability, lymph node metastasis, HLA-DR expression, and u-PA expression had a significant influence on survival after surgery. Multivariate analysis showed that surgical curability, HLA-DR expression, and u-PA expression independently influenced survival. Patients positive for HLA-DR expression [HLA-DR (+)] and regative for u-PA expression [u-PA (-)] had the best survival: 25-month median survival and 25% 5-year survival rate. Patients who were HLA-DR (+) and u-PA (+), or HLA-DR (-) and u-PA (-) had a median survival of 10 months, a 1-year survival rate of 46.2%, and a 2-year survival rate of 7.7%. HLA-DR (-) and u-PA (+) patients had the worst survival: 4.5-month median survival and 0% 1-year survival.CONCLUSIONS: These findings suggest that host immune response and proteolytic activity in the primary tumor may determine malignant potential, and that the combination of positive-HLA-DR and negative-u-PA expression in cancer cells may be a predictor of prolonged survival in stage IV gastric cancer patients.
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PMID:Expression of HLA-DR and urokinase-type plasminogen activator in stage IV gastric cancer. 1195 46

Twenty-four (24) pretreated patients with relapsed high-risk resected The American Joint Committee on Cancer (AJCC) stage IIA-IV melanoma received adjuvant peptide vaccinations derived from the melanosomal antigens MelanA/MART1, MAGE-1, gp100, and tyrosinase, according to patient tumor-associated human leukocyte antigen (HLA) restricted antigen expression, in combination with granulocyte-macrophage colony-stimulating factor (GM-CSF). Pretreatment was comprised of surgery (n=23 primary tumor; n=23 metastases), local radiotherapy (n=2), immunotherapy (n=23), chemotherapy (n=10), and chemoimmunotherapy (n=1), respectively. All patients received peptide vaccines in an adjuvant setting. Seven (7) patients were relapse free for 3+ up to 25+ months. Of the patients exhibiting progressive disease (n=17), 13 patients developed metastases during vaccination (9 local, 4 distant), and 4 patients developed metastases (2 local, 2 distant) after finishing vaccine therapy. Two (2)-year local and distant metastases-free survival, 2-year distant metastases-free survival, and 2-year overall survival were calculated as 8.6%, 68%, and 85%, respectively. Vaccine treatment was well tolerated, with no severe side-effects. Twenty (20) of 24 patients developed local delayed-type hypersensitivity (DTH) reactions to synthetic peptide vaccination. Transient fever (n=2) and pain in muscle/bone (n=2) occurred rarely. In conclusion, antigenic peptide vaccination, combined with GM-CSF, is safe and may yield clinical benefits in relapsed high-risk resected melanoma patients.
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PMID:GM-CSF plus antigenic peptide vaccination in locally advanced melanoma patients. 1780 50

An optimized antigen-presenting cell for tumor immunotherapy should produce a robust antigen specific cytotoxic T lymphocytes (CTL) response to tumor-associated antigens, which can persist in vivo and expand on antigen reencounter. Interleukin (IL)-21 synergizes with other gamma-chain cytokines to enhance the frequency and cytotoxicity of antigen-specific CTL. As T cells themselves may serve as effective antigen-presenting cells (T antigen-presenting cells; TAPC) and may be useful in vivo as cellular vaccines, we examined whether CD8(+) T cells genetically modified to produce IL-21 could induce immune responses to tumor associated antigen peptides in healthy human leukocyte antigen-A2(+) donors. We found that IL-21 modified TAPC enhanced both the proliferation and survival of MART-1 specific CD8(+) T cells, which were enriched by >8-fold over cultures with control nontransgenic TAPC. MART-1-specific CTL produced interferon-gamma in response to cognate peptide antigen and killed primary tumor cells expressing MART-1 in a major histocompatibility complex restricted manner. IL-21 modified TAPC similarly enhanced generation of functional CTL against melanoma antigen gp100 and the B-cell chronic lymphocytic leukemia associated RHAMM antigen. Antigen-specific CTL generated using IL-21 gene-modified TAPC had a central memory phenotype characterized by CD45RA(-), CD44(high), CD27(high), CD28(high), CD62L(high), and IL-7 receptor-alpha(high), contrasting with the terminal effector phenotype of CTL generated in the absence of IL-21. Thus, TAPC stimulation in the presences of IL-21 enhances proliferation of tumor antigen-specific T cells and favors induction of a central memory phenotype, which may improve proliferation, survival, and efficacy of T-cell based therapies for the treatment of cancer.
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PMID:Genetic modification of T cells with IL-21 enhances antigen presentation and generation of central memory tumor-specific cytotoxic T-lymphocytes. 1956 36

Cancer cells frequently exhibit defects in apoptosis, which contribute to increased survival and chemotherapeutic resistance. For example, genetic mutations or abnormal proteasomal degradation can reduce expression of Bax which limits apoptosis. In cancers where abnormal proteasomal degradation of Bax occurs, we hypothesized that Bax peptides that bind to human leukocyte antigen (HLA) class I molecules would be generated for presentation to CD8(+) T cells. To test this hypothesis, we generated T cells against pooled Bax peptides, using the blood of healthy human donors. Although T-cell responses were of low frequency (0.15%), a CD8(+) T-cell clone (KSIVB17) was isolated that optimally recognized Bax(136-144) peptide (IMGWTLDFL) presented by HLA-A*0201. KSIVB17 was able to recognize and kill a variety of HLA-matched cancer cells including primary tumor cells from chronic lymphocytic leukemia (CLL). No reactivity was seen against HLA-matched, nontransformed cells such as PHA blasts and skin fibroblasts. Furthermore, KSIVB17 reactivity corresponded with the proteasomal degradation patterns of Bax protein observed in cancer cells. Taken together, our findings suggest a new concept for tumor antigens based on regulatory proteins that are ubiquitously expressed in normal cells, but that have abnormally enhanced degradation in cancer cells. Bax degradation products offer candidate immune antigens in cancers such as CLL in which increased Bax degradation correlates with poor clinical prognosis.
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PMID:A novel tumor antigen derived from enhanced degradation of bax protein in human cancers. 2169 78


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