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)

To explore the potential of recombinant vectors based on recombinant adeno-associated virus (rAAV) for cancer vaccination, we investigated the transduction efficiency of rAAV into cancer cells ex vivo. Infection of human epithelial cancer cell lines with rAAV carrying reporter genes encoding beta-galactosidase (rAAV/LacZ) or luciferase (rAAV/Luc) resulted in high levels of reporter gene expression (>90% positive cells). In marked contrast, rAAV poorly transduced all murine tumor cell lines, as well as human hematopoietic cell lines. Either irradiation or adenovirus infection of tumor cells prior to rAAV infection induced a 10- to 100-fold increase of reporter gene expression. To determine the transduction efficiency of rAAV into primary cancer cells, freshly isolated, irradiated tumor cells from malignant melanoma and ovarian carcinoma patients were infected with rAAV/Luc, resulting in up to 6.9-fold higher levels of gene expression than in a HeLa tumor cell line. Time course experiments with freshly isolated tumor cells infected with rAAV/Luc showed maximal levels of luciferase expression between days 3 and 9 posttransduction. Simultaneous infection of primary tumor cells with up to three rAAV vectors containing genes encoding the immunostimulatory proteins B7-2 (CD86), p35 subunit of IL-12, and p40 subunit of IL-12 resulted in high expression of B7-2 in more than 90% of the tumor cells and in the secretion of high levels of IL-12. Taken together, our results demonstrate that rAAV efficiently transduces freshly isolated human, epithelial tumor cells and might therefore be a potent tool to produce improved, gene-modified cancer vaccines.
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PMID:Recombinant adeno-associated virus for the generation of autologous, gene-modified tumor vaccines: evidence for a high transduction efficiency into primary epithelial cancer cells. 960 16

Early reports suggest that the costimulatory molecule CD86 (B7-2) has sporadic efficacy in tumor immunity, whereas changes in cancer immunity mediated by the MHC class II transactivator (CIITA) have not been extensively investigated. CIITA activates MHC class II expression in most cells; however, in the Line 1 lung carcinoma model system, CIITA activates MHC class I and well as class II. Here we show that CD86 is very effective in inducing a primary immune response against Line 1. Tumor cells expressing CD86 grew in only 50% of the mice injected with live cells, and those mice that developed tumors did so with significantly delayed kinetics. Furthermore, irradiated CD86-expressing Line 1 cells served as an effective tumor vaccine, demonstrating that CD86 is effective in inducing tumor immunity in the Line 1 system. These data suggest that if CIITA and CD86 cooperate, enhanced tumor immunity could be achieved. CIITA alone was mildly beneficial in slowing primary tumor growth but only when expressed at low levels. Clones expressing high levels of class II MHC grew as fast as or faster than parental tumor, and CIITA expression in a tumor vaccine assay lacked efficacy. When CIITA and CD86 were coexpressed, there was no cooperative immune protection from tumor growth. Cells that coexpress both genes also failed as a cancer vaccine, suggesting a negative role for CIITA in this lung carcinoma. These data suggest that human cancer vaccine trials utilizing CIITA gene therapy alone or in combination with CD86 should be approached with caution.
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PMID:Combination gene therapy with CD86 and the MHC class II transactivator in the control of lung tumor growth. 1035 84

Although tumor-specific T lymphocytes recognize tumor-associated antigens (TAA) present on their cell surface via major histocompatibility complex (MHC) molecules, T cells require other activating signals. These are provided by costimulatory molecules, including B7-1 (CD80), B7-2 (CD86) and intercellular adhesive molecule 1 (ICAM-1; CD54). Transfecting mouse tumor cell lines with the B7 gene can lead to primary tumor rejection and the establishment of protective immunity. However, some studies have shown that the B7 effect upon T-cell-dependent tumor immunity is limited. Therefore, we examined the antitumor effects of recombinant interleukin 12 (IL-12) and genetically engineered glioma cells expressing B7-1 or both B7-1 and ICAM-1. Vaccination of mice with B7-1-expressing tumor cells substantially inhibited the growth of subcutaneously inoculated gliomas but not those located in the brain. Vaccination with B7-1-expressing tumor cells and systemic recombinant IL-12 (rIL-12) was more effective than either B7-1-expressing tumor cells or rIL-12 alone. Our murine brain tumor model also showed that vaccination with tumor cells expressing both B7-1 and ICAM-1 combined with rIL-12 prolonged survival. We have demonstrated the therapeutic potential of vaccination with rIL-12 and tumor cells expressing both B7-1 and ICAM-1 in the control of glioma growth.
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PMID:Induction of effective antitumor immunity in a mouse brain tumor model using B7-1 (CD80) and intercellular adhesive molecule 1 (ICAM-1; CD54) transfection and recombinant interleukin 12. 1041 70

Augmenting immunogenicity by genetically modifying tumor cells to express costimulatory molecules has proven to be a promising therapeutic strategy in murine tumor models and is currently under investigation in human clinical trials for metastatic cancer. However, there are significant technical and logistic problems associated with implementing strategies requiring direct gene modification of primary tumor cells. In an effort to circumvent these problems, we are developing a strategy in which the costimulatory signal required for tumor-specific T lymphocyte activation is provided by a genetically modified human fibroblast (trans-costimulation). We have evaluated the efficiency of CD80- and CD86-mediated trans-costimulation in the activation of human CD8+ and CD4+ T lymphocytes in MHC class I- and class II-restricted lymphoproliferation reactions. Our studies demonstrate that the efficiency of CD80- or CD86-mediated trans-costimulation of purified human CD8+ and CD4+ T lymphocytes is comparable to cis-costimulation under defined conditions. Moreover, a dose-response relationship consistent with the predicted two-hit kinetics of the reaction was evident in trans-costimulation reactions in which the ratio of target cells expressing either signal 1 or signal 2 was varied incrementally from 1:10 to 10:1. Importantly, the level of cell-surface CD86 required for trans-costimulation is equivalent to that constitutively expressed by human peripheral blood monocytes. These results may have significant implications for the clinical implementation of this type of cancer immunotherapy and also raise questions about the possibility of trans-costimulating autoreactive T lymphocytes in vivo.
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PMID:Human fibroblasts transduced with CD80 or CD86 efficiently trans-costimulate CD4+ and CD8+ T lymphocytes in HLA-restricted reactions: implications for immune augmentation cancer therapy and autoimmunity. 1047 93

The generation of fused cells between dendritic cells (DC) and tumor cells is a very effective approach for tumor antigen presentation in cancer immunotherapy. However, the application of this approach in clinical studies is limited by the need for established tumor cell lines and the time-consuming procedures for selecting and expanding the fused cells. In the current study, the authors report a rapid, novel approach to produce fused cells between DCs and primary tumor cells from patients with malignant melanoma. Peripheral blood DCs and a primary tumor cell culture were generated from the same patients, labeled with fluorescent green and red dyes, respectively, and fused. The fused cells were isolated by fluorescence-activated cell sorting. Because the fused cells do not need to be expanded, these cell hybrids have been named instant dendritomas. Fluorescence-activated cell sorting analysis showed that instant dendritomas express the key molecules for antigen presentation (HLA-A, B, C; HLA-DR; CD80; and CD86). In vitro studies have shown that instant dendritomas effectively activated autologous CD8+ T lymphocytes to proliferate and secret interferon-gamma. More importantly, the activated CD8+ T lymphocytes effectively lysed the patients' primary tumor cells. This approach represents a practical clinical strategy for cancer immunotherapy.
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PMID:A rapid, novel strategy to induce tumor cell-specific cytotoxic T lymphocyte responses using instant dentritomas. 1126 78

SUMMARY: The generation of fused cells between dendritic cells (DC) and tumor cells is a very effective approach for tumor antigen presentation in cancer immunotherapy. However, the application of this approach in clinical studies is limited by the need for established tumor cell lines and the time-consuming procedures for selecting and expanding the fused cells. In the current study, the authors report a rapid, novel approach to produce fused cells between DCs and primary tumor cells from patients with malignant melanoma. Peripheral blood DCs and a primary tumor cell culture were generated from the same patients, labeled with fluorescent green and red dyes, respectively, and fused. The fused cells were isolated by fluorescence-activated cell sorting. Because the fused cells do not need to be expanded, these cell hybrids have been named instant dendritomas. Fluorescence-activated cell sorting analysis showed that instant dendritomas express the key molecules for antigen presentation (HLA-A, B, C; HLA-DR; CD80; and CD86). In vitro studies have shown that instant dendritomas effectively activated autologous CD8+ T lymphocytes to proliferate and secret interferon-gamma. More importantly, the activated CD8+ T lymphocytes effectively lysed the patients' primary tumor cells. This approach represents a practical clinical strategy for cancer immunotherapy.
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PMID:A Rapid, Novel Strategy to Induce Tumor Cell-Specific Cytotoxic T Lymphocyte Responses Using Instant Dendritomas. 1144 68

Intraoperative lymphatic mapping and sentinel lymphadenectomy (LM/SL) provides a unique opportunity for assessing potential immunologic interactions between the primary tumor and regional lymph node basin. We performed LM/SL in 24 patients with early-stage melanoma and resected an additional nonsentinel node (non-SN) in each case. Sentinel nodes (SNs) and non-SNs were evaluated by routine pathologic analysis, and a portion of each node was processed for expression of three dendritic markers of activation (CD80, CD86, CD40) and their corresponding T-cell receptors (CTLA-4 and CD28). Twenty (83%) patients had matched SNs and non-SNs. A total of 26 nodal pairs were obtained because one patient had three pairs and two other patients each had two pairs. Reverse transcriptase-polymerase chain reaction (RT-PCR) analyses of paired SNs and non-SNs demonstrated a marked reduction in semiquantitative expression of CD80 (77%), CD86 (77%), and CD40 (85%), as well as CTLA-4 (88%) and CD28 (85%) in SNs. The diminished expression appeared to be unrelated to B-cell (CD20) and T-cell (CD2) expression. A quantitative reduction in dendritic cell markers in SNs may be important in the immunologic interaction between the primary site and regional lymph node basin and may also provide useful criteria for identifying SNs.
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PMID:Surgical and molecular approaches to the sentinel lymph nodes. 1159 94

Intraoperative lymphatic mapping and sentinel lymphadenectomy has become an increasingly popular technique for staging the regional lymph nodes in early-stage melanoma. This operative technique allows for detailed pathologic analysis of the first (or sentinel) lymph node in direct connection with the primary tumor, and provides a unique opportunity for assessing potential immunologic interactions between the primary tumor and regional lymph node basin. We performed lymphatic mapping and sentinel lymphadenectomy on 25 patients with early-stage melanoma and resected an additional nonsentinel node in each case. Sentinel and nonsentinel nodes were evaluated by routine pathologic analysis. A portion of each node was processed for expression of the dendritic markers of activation CD80, CD86, and CD40, and their corresponding T-cell receptors CTLA-4 and CD28. Of 25 patients undergoing lymphatic mapping and sentinel lymphadenectomy, 20 (80%) had matched sentinel and nonsentinel nodes. A total of 26 matched lymph node sets were obtained: three pairs from one patient and two from an additional two patients. Reverse transcription polymerase chain reaction analyses of corresponding sections of the sentinel and nonsentinel nodes demonstrated a marked reduction in semiquantitative expression of CD80 (77%), CD86 (77%), and CD40 (85%), as well as CTLA-4 (88%) and CD28 (85%) in sentinel as compared to nonsentinel nodes. The diminished expression of the dendritic cell markers appeared to be unrelated to the B-cell (CD20) and T-cell (CD2) expression. Lymphatic mapping and sentinel lymphadenectomy allows for detailed pathologic and molecular characterization of sentinel nodes. Our results suggest a quantitative reduction in dendritic cell markers in sentinel as compared to nonsentinel nodes, which may be important in the immunologic interaction between the primary site and regional lymph node basin and may also serve as useful criteria for identifying sentinel nodes.
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PMID:Dendritic cell function in sentinel nodes. 1182 80

Production of immunosuppressive factors is one of the mechanisms by which tumors evade immunosurveillance. Soluble factors hampering dendritic cell (DC) development have recently been identified in culture supernatants derived from tumor cell lines. In this study, we investigated the presence of such factors in 24-h culture supernatants from freshly excised solid human tumors (colon, breast, renal cell carcinoma, and melanoma). While primary tumor-derived supernatant (TDSN) profoundly hampered the in vitro DC differentiation from CD14(+) plastic-adherent monocytes or CD34(+) precursors (based on morphology and CD1a/CD14 phenotype), the effects of tested tumor cell line-derived supernatants were minor. Cyclooxygenase (COX)-1- and COX-2-regulated prostanoids present in the primary TDSN were found to be solely responsible for the observed hampered differentiation of monocyte-derived DC (MoDC). In contrast, both prostanoids and IL-6 were found to contribute to the TDSN-induced inhibition of DC differentiation from CD34(+) precursor cells. While the addition of TDSN during differentiation interfered with the ability of CD34-derived DC to stimulate a primary allogeneic T cell response, it actually increased this ability of MoDC. These opposite effects were correlated to different effects of the TDSN on the expression levels of CD86 and HLA-DR on the DC from the different precursor origins. Although TDSN increased the T cell-stimulatory capacity of MoDC, TDSN inhibited the IL-12 production and increased the IL-10 production of MoDC, thus skewing them to a type-2 T cell-inducing phenotype. In conclusion, this study demonstrates that primary tumors negatively impact DC development and function through COX-1 and -2 regulated factors, whereas tumor-derived cell lines may lose this ability upon in vitro propagation.
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PMID:Prostanoids play a major role in the primary tumor-induced inhibition of dendritic cell differentiation. 1197 Sep 75

Our aim was to evaluate whether the number of circulating lymphocytes expressing costimulatory molecules can be associated with melanoma prognosis. We determined the concentration of peripheral blood lymphocytes, which expressed the CD80/CD86 or CD28/CTLA-4 molecules, in 38 patients with cutaneous melanoma and 27 controls. The number of each cell subset was compared between patients and controls, as well as between groups of patients stratified according to Breslow thickness of the primary tumor (< or = 2 mm vs > 2 mm) or to survival after 3 years. The concentration of circulating lymphocytes expressing the CD80/CD86 molecules was not significantly different between patients and controls. There was a lower number of CD3(+)CD8(+)CD28(+) cells, as well as a higher CD3(+)CD8(+)/CD3(+)CD8(+)CD28(+) cell ratio, in melanoma patients than in controls. Melanoma patients with thinner tumors and those surviving revealed an increase of CD19(+)CD80(+) and CD19(+)CD80(+)CD86(+) cells, as well as a higher concentration of CD3(+)CD4(+)CD28(+) cells. CD80(+) B cells and a low CD8 suppressor/cytolytic cell ratio correlate with a good prognosis in melanoma. Our findings support our conclusion that CD80(+) B cells may be important antigen presenting cells that can contribute to an antimelanoma immune response and are candidates to be monitored in melanoma patients.
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PMID:Changes in the number of CD80(+), CD86(+), and CD28(+) peripheral blood lymphocytes have prognostic value in melanoma patients. 1287 58


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