Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In this study we have investigated the effects of thymosin alpha 1 (T alpha 1) and interleukin-2 (IL-2), singly or in combination with cyclophosphamide (CY), on tumor growth, survival and cytotoxicity in C57Bl/6NCrlBR mice with Lewis lung carcinoma (3LL). Combined administration of T alpha 1 plus IL-2, after CY treatment, was much more effective than use of each biological response modifier (BRM) alone, and induced complete tumor regression in all of the mice studied. Combination immunotherapy alone without CY only slightly reduced the rate of tumor growth, and these results are in accordance with previous studied which showed that the 3LL carcinoma is resistant to cytokines. Combined chemo-immunotherapy also increased the cytotoxicity of spleen cells and markedly enhanced long-term survival in all treated animals. Depletion of immune cells, using either total-body sub-lethal irradiation (400 rads) or antibodies directed against T-cell (anti-CD4 and CD8) or NK-cell (anti-asialo GM1) populations, abolished the positive response to combination therapy. Histological analysis of the tumors obtained from mice treated with combination chemo-immunotherapy revealed a high number of infiltrating lymphoid cells surrounding a well-circumscribed area of necrosis consisting solely of dead cells. Our studies show that T alpha 1 potentiates IL-2-induced cytotoxic activities in vitro as well in vivo, and that these compounds have a powerful anti-tumor action when associated with chemotherapy.
 ...
PMID:Combination therapy with thymosin alpha 1 potentiates the anti-tumor activity of interleukin-2 with cyclophosphamide in the treatment of the Lewis lung carcinoma in mice. 173 18

Methods have recently been described for the isolation and expansion of lymphocytes that have trafficked into animal and human tumors. These CD8-positive tumor-infiltrating lymphocytes (TIL's) have exceptional trafficking ability to, and efficacy against, tumor targets in extracranial sites. Prior to Phase I clinical trials for patients with gliomas, adoptive immunotherapy with TIL's was studied in a mouse model of primary brain tumors to determine if intracerebral tumors have a similar response. Glioma 261 (GL261) tumors were grown in the subcutaneous space of C57BL/6 mice. After enzymatic digestion, the cells were incubated in vitro with interleukin-2 (IL-2) until a confluent population of T lymphocytes was present. The in vitro efficacy of these TIL's was tested against fresh GL261 targets with a chromium release assay; the in vivo efficacy was tested against GL261 tumors in the liver and against irradiated and nonirradiated GL261 tumors in the brain. Mice received one of the following: intraperitoneal saline; intraperitoneal IL-2 (7500 to 50,000 U three times daily for 5 days); IL-2 plus intravenous TIL's (1 to 3 x 10(7) cells); 10 Gy cranial irradiation; irradiation plus IL-2; or irradiation plus IL-2 plus TIL's. The TIL preparation killed 77% of tumor targets in 4 hours at an effector:target ratio of 100:1. In animals with GL261 tumors in the liver, at 2 weeks there were 93 +/- 37, 128 +/- 45, and 21 +/- 14 liver metastases in the control, IL-2, and IL-2 plus TIL groups, respectively. However, in animals with GL261 tumors in the brain, no treatment group had an increased survival rate compared to the control group. It is concluded that, although TIL and IL-2 immunotherapy can be used effectively to treat brain tumors in vitro and at sites outside the central nervous system, it is ineffective against the same type of tumor in the brain. Different methods of delivery or different combinations of these immunomodulators may be more effective; however, based on these findings, treatment of patients with IL-2 and TIL cannot be recommended until efficacy has been demonstrated in an animal model.
 ...
PMID:Treatment of murine primary brain tumors with systemic interleukin-2 and tumor-infiltrating lymphocytes. 173 33

The histologic and immunohistologic features of two morphologically similar splenic tumors, a capillary hemangioma and a splenic hamartoma, are reported. The hemangioma was composed predominantly of small vascular channels lined by endothelium expressing factor VIII-related antigen and lacking T-subset antigen (CD8). In contrast, the splenic hamartoma was predominantly a spindle cell lesion with numerous vascular channels coursing through the tumor; these contained splenic-type endothelium expressing both CD8 and factor VIII-related antigen. Our results justify the concept that the splenic hamartoma is a tumor of splenic origin or a true hamartoma and is distinct from the splenic capillary hemangioma.
 ...
PMID:Splenic hamartoma and capillary hemangioma are distinct entities: immunohistochemical analysis of CD8 expression by endothelial cells. 174 32

We have previously shown that thymocytes from low-dose melphalan (L-phenylalanine mustard)-treated MOPC-315-tumor-bearing mice (melphalan TuB) are able to generate an enhanced level of anti-MOPC-315 cytotoxicity, as compared to thymocytes from untreated MOPC-315-tumor-bearing mice or thymocytes from untreated or low-dose melphalan-treated normal mice, upon in vitro stimulation with MOPC-315 tumor cells in the presence of a low concentration of recombinant interleukin-2 (rIL-2). Here we show that the generation of enhanced anti-MOPC-315 cytotoxicity by melphalan TuB thymocytes depends on the ability of the thymocytes to proliferate. In addition, the ability of melphalan TuB thymocytes to generate an enhanced level of anti-MOPC-315 cytotoxicity correlated with their ability to proliferate more readily than thymocytes from untreated tumor-bearing mice and thymocytes from untreated or melphalan-treated normal mice in response to stimulation with MOPC-315 tumor cells plus a low concentration of rIL-2. Moreover, although fresh melphalan TuB thymocytes do not contain a higher percentage of phenotypically mature cells (i.e., CD4-/CD8+ or CD4+/CD8-) than do thymocytes from normal mice or untreated tumor-bearing mice, after a 5-day culture with both MOPC-315 tumor cells and a low concentration of rIL-2, cultures of thymocytes from melphalan TuB contained a much higher percentage of CD4-/CD8+ (but not CD4+/CD8-) cells than did cultures of thymocytes from the other two sources. Since CD4-/CD8+ cells were previously shown to be responsible for the exertion of antitumor cytotoxicity by thymocytes stimulated with MOPC-315 in vitro, our results indicate that the enhanced antitumor cytotoxicity exerted by melphalan TuB thymocytes following in vitro stimulation with MOPC-315 tumor cells in the presence of a low concentration of rIL-2 is due, at least in part, to an expansion of the pool of CD4-/CD8+ effector cells.
 ...
PMID:Enhanced expansion of the thymic CD8+ cell subset as a potential mechanism for the generation of enhanced antitumor cytotoxicity by thymocytes from low-dose melphalan-treated MOPC-315 tumor bearers. 176 Aug 20

Lymphocyte subsets were examined in renal cell carcinoma (TILs), adjacent non-tumor renal tissue and peripheral blood (PBLs) by flow cytometry and histochemistry in eighteen patients with renal cell carcinoma. CD5-positive cells were predominant in the TILs in 14 patients. In the renal cell carcinoma tissue, CD8-positive cells were predominant over CD4-positive cells, resulting in a less than unity ratio of CD4/CF8-positive cells. The lymphocyte number was significantly in adjacent normal renal tissue than in renal cell carcinoma. However, lymphocyte subsets ratios were not significantly different between these two tissues. PBLs showed the same proportions (CD4/CD8 mean 1.9 +/- 0.8) as the previously published healthy controlled data. The proportions of CD8-positive cells were significantly increased (p less than 0.05) and those of CD4-positive cells were also significantly decreased (p less than 0.01) in the TILs. The infiltrating pattern of TILs in 17 patients was divided histochemically into cluster (N = 7), single (N = 4), and mixed types (N = 6). The cluster and mixed types were significantly more common in grade 1 tumors and the single type was more common in the grade 2 tumors (p less than 0.05). The pT3 tumors showed the single type of TIL infiltration pattern, but showed no significant difference. In the cluster pattern of TILs, CD8-positive cells were surrounded by CD4-positive cells. Non-tumorous kidneys showed no infiltration of lymphocytes, except in 2 patients of pyelonephritis. These results suggest that cytotoxic T-cells stained as CD8 play an immunoreactive role against renal cell carcinoma.
 ...
PMID:[Lymphocytic subsets of tumor tissue, non tumorous kidney, and the peripheral blood in primary renal cell carcinoma]. 176 68

Optimal conditions for removing leukemic cells from human bone marrow with monoclonal antibodies (mAb) and magnetic immunobeads were investigated. Monodisperse 3 microns polystyrene microspheres containing magnetite were coated with affinity-purified rabbit antimouse IgG at 4 degrees C, pH 9.6 for 18 h. SKW-3 cells (T-CLL cell line) were marked with the supravital DNA stain Hoechst 33342, seeded into normal human bone marrow, and then incubated with the mAb CD1, CD6, and CD8 at 4 degrees C for 30 min. In preliminary experiments REH cells (cALL cells) and mouse anti-REH cell antibodies were used to find the most favorable conditions for the binding of magnetic beads to tumor cells. Optimal formation of cell-bead rosettes was achieved by rotating beads and tumor cells together at room temperature at a concentration of 1 x 10(7) cells/ml, a bead: tumor cell ratio of 100:1 and an incubation time of one hour. The novel magnetic separation apparatus consists of three polystyrene chambers connected by silicone rubber tubing. The chambers contain four steel inserts each equipped with 32 nickel wires, which are magnetized by permanent magnets in such a way that the inhomogeneous high gradient magnetic field could be established within the cell suspension containing the cells to be depleted. The fluid flow was established by a peristaltic pump. At a flow rate of 1.5 ml/min and a field strength of 160 kA/m, no beads could be detected in the purged marrow. A cocktail of the three mAb was more effective than any single antibody in forming bead-cell rosettes. Two sequential purging cycles were superior to one. The marrow recovered was highly viable as assessed by trypan blue dye exclusion and by growth of CFU-GM.
 ...
PMID:Model experiments for immunomagnetic elimination of leukemic cells from human bone marrow. Presentation of a novel magnetic separation system. 178 86

Factor AF2, a now standardized extract from liver and spleen of newborn lambs, showed myeloprotective capacity on platelet- and erythrocyte-count as well as on hemoglobinconcentration in patients undergoing aggressive chemotherapy. In addition, a possible influence on prolonged remission duration in patients with mammary carcinoma had been claimed. In this study, the effect of Factor AF2 on mitogen-induced interferon-gamma release by PBMC was tested in 23 healthy humans and in 23 tumor patients. All patients were prior to surgery and had not yet received radio- or chemotherapy at the time of examination. The interferon-gamma concentration of the supernatants was measured using an enzyme-linked immunosorbent assay (ELISA). The cells were stimulated with PHA at 7.5 micrograms/ml. In the reference group, interferon-gamma concentration rose to 26 units/ml and to 15.5 units/ml in the tumor patients. In the reference persons, an addition of Factor AF2 at concentrations from 10(1) micrograms/ml to 10(3) micrograms/ml resulted in a small non-significant decrease of interferon-gamma release. At 10(4) micrograms/ml, neither test group showed measurable interferon-gamma concentration. In the tumor patients, cocultivation with Factor AF2 until concentration of 10(2) micrograms/ml resulted in a dose-dependent increase of interferon-gamma release, where 20.5 units/ml interferon-gamma were reached. At 10(3) micrograms/ml, Factor AF2 showed no effect on interferon-gamma release compared with the stimulation with mitogen alone. Flow-cytometry analysis of CD3, CD4, CD8, CD16, CD19, CD56, and HLA-DR expression of the PBMC deriving either from reference persons or from patients revealed an almost identical distribution. A slight difference in CD16-positive and HLA-DR positive cells, respectively, was not significant.
 ...
PMID:Improvement of impaired mitogen-induced interferon-gamma release of peripheral blood mononuclear cells derived from tumor patients by Factor AF2. 178 74

Levamisole, an anthelminthic drug with immunological properties, has recently been reported to have antitumor activity when administered with 5-fluorouracil in patients with Duke's C colorectal carcinoma. The mechanism of this antitumor effect is unknown, but has been postulated to be related to levamisole's immunomodulatory properties. To define further the immunomodulatory activities of levamisole, we studied the in vitro effects of levamisole on monocyte and lymphocyte cytotoxicity, activation, and proliferation; induction of cytokine-induced proteins; and expression of tumor-associated antigens. Experiments utilized peripheral blood mononuclear cells from normal donors incubated in the presence of increasing concentrations of levamisole (0.1 to 100 micrograms/ml). Levamisole had no consistent effect on induction of 2',5'-oligoadenylate synthetase activity or indoleamine-2,3-dioxygenase activity, or production of tumor necrosis factor. Levamisole had no effect on monocyte cytotoxicity or expression of HLA-DR, HLA-DQ, HLA-DP, and the Fc receptor. Similarly, levamisole had no significant effect on NK or LAK cytotoxicity or the immunological activation of T-lymphocytes, assessed by expression of CD3, CD4, CD8, CD16, CD25, and CD56. Proliferation of lymphocytes from normal donors, patients with benign polyps, and patients with malignancies, with or without IL-2 or irradiated LS174T cells, was not significantly increased overall. No significant enhancement in the expression of three tumor-associated antigens (880364, NRCO-4, and ING-1) and the intercellular adhesion molecule-1 (ICAM-1) antigen on four human cancer cell lines was observed following in vitro exposure to levamisole. We conclude that levamisole is not a potent modulator of the immune parameters we examined, and that the mechanism behind the unique clinical interaction between levamisole and 5-fluorouracil in colorectal carcinoma remains to be identified.
 ...
PMID:Immunological effects of levamisole in vitro. 179 Jan 37

Conditions for generating and expanding cytotoxic tumor-specific, tumor-infiltrating lymphocytes (TIL) were studied to improve the efficacy of adoptive cancer immunotherapy. Thus, we have examined the growth and cytolytic patterns of bulk culture TIL from human renal cell carcinoma (RCC) cultured in low (20 U/ml) or high (1,000 U/ml) dose interleukin (IL)-2, with or without irradiated autologous tumor stimulation. By 55 days in culture, TIL grown in the presence of IL-2 without tumor stimulation lost their lytic activity, whereas those exposed to tumor stimulation maintained high levels of cytotoxicity against autologous and/or nonautologous tumor targets. Only TIL grown with low dose IL-2 and autologous tumor maintained long-term (over 4 months in culture) specific cytotoxicity against the autologous tumor, even upon cryopreservation and regrowth. These TIL were 88-97% and 80% positive for CD3 and CD8, with a persistent subset exhibiting CD4+ CD8+ double positive staining. Their specific cytotoxic activity was major histocompatibility complex Class I-restricted and inhibited by pretreating the TIL with anti-CD3 monoclonal antibody. TIL exposed to the four types of culture conditions, low or high dose IL-2, with or without irradiated autologous tumors, and exhibiting different lytic specificities, all expressed mRNA for interferon-gamma and tumor necrosis factor (TNF)-alpha, but not for IL-1-beta, IL-4, IL-6, and granulocyte-macrophage colony stimulating factor. The degree of TNF-alpha mRNA expression correlated with the degree of autologous tumor-specific cytotoxicity of these TIL. This initial report demonstrates that antigen-specific cytotoxicity against the autologous tumor does, in fact, exist within the RCC tumors.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Autologous tumor-specific cytotoxicity of tumor-infiltrating lymphocytes derived from human renal cell carcinoma. 179 Jan 42

CD3,4 (anti-CD3:anti-CD4) bispecific monoclonal antibodies (BSMAB) cause a profound decrease in CD4+ T cells and a marked proliferation of CD8+ T cells in peripheral blood mononuclear cells in vitro. CD3,8 (anti-CD3:anti-CD8) BSMAB causes a reciprocal decrease in CD8+ T cells and a proliferation of CD4+ T cells. The major effector of CD4+ T cell cytolysis in the presence of CD3,4 resides in the CD8+ T cell population. In contrast, both the CD4+ and CD8+ T cells are effective mediators of cytolysis of the CD8+ T cells in the presence of the CD3,8. The likely underlying mechanism in each case is bridging of the CD4 and CD8 of the target cells to the CD3 complexes of the effector cells by antibodies, mimicking the natural encounter between a cytolytic T cell and its target. Proliferation studies indicated that CD3,4 and CD3,8 each can induce proliferation of both CD4+ and CD8+ T cells in the presence of accessory cells. These results suggest that the major selection of the BSMABs occurs via selective destruction of one T cell subset with concurrent stimulation of the remaining CD3+ population. Potential applications of the selective destruction and proliferation include study and manipulation of the T cell subsets in HIV infections, tumor infiltrating lymphocytes, autoimmune diseases, and graft rejection.
 ...
PMID:Selective reduction and proliferation of the CD4+ and CD8+ T cell subsets with bispecific monoclonal antibodies: evidence for inter-T cell-mediated cytolysis. 182 87


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>