Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0006142 (breast cancer)
 160,383 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The antitumor activity of natural human tumor necrosis factor (TNF) on a human hepatoma cell line PLC/PRF/5 was studied in vitro. TNF produced by the LuKII human lymphoblastoid cell line showed a cytostatic effect on the hepatoma cells, whereas the growth of non-tumorigenic Chang liver cells was little affected. The combined effects of TNF and interferon-gamma (IFN-gamma) were additive on the PLC/PRF/5 cells as shown by statistical analyses. The same combination showed synergistic effects on a human breast cancer cell line BT-20, which was highly sensitive to TNF. These data may provide some informations concerning the use of TNF in the treatment of hepatoma.
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PMID:Antitumor effect of human necrosis factor on human hepatoma cells PLC/PRF/5. 310 17

The human breast cancer cells BT-20 were treated for 18 months in the continuous presence of interferon-gamma (HuIFN-gamma; 500 U/ml). These cells have become completely resistant to HuIFN-gamma and interestingly also to IFN-alpha 2. However, the expression of HLA-DR and the regulation of cell adhesion to tissue culture plastic remained partially under the domain of HuIFN-gamma. A reduced number of IFN-gamma binding sites in comparison to the wild-type cells were observed on the IFN-resistant BT-20 cells.
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PMID:Characterization of an interferon-resistant mutant of the human breast cancer cell line BT-20. 311 48

Effects of human recombinant-DNA derived interferon-gamma and -alpha 2 on the adhesion of cultured breast cancer cells (BT-20, ZR-75.1, MCF-7, 734-B and Hs-578-T), larynx carcinoma cells (HEP-2), epidermoid carcinoma cells (KB), lung carcinoma cells (CCL 185), and ovarian carcinoma cells (1847) to the surface of cell culture plastic dishes were studied. Layered cells were detached after a 3-day treatment with interferon either by trypsin-EDTA, trypsin, protease or cooling to 4 degrees C. Treatment with interferon-gamma (500 unit/ml) significantly increased the incubation time for trypsin-EDTA, EDTA and at 4 degrees C necessary to bring cells into suspension for the 4 cell lines BT-20, ZR-75.1, MCF-7 and HEP-2. Interferon-alpha 2 was not able to induce a similar effect. Reattachment of interferon-gamma treated ZR-75.1 cells was not increased after harvesting by trypsinization or EDTA action. Decreased adhesion of cultured cells is associated with transformation and the effects of interferon-gamma may be explained by reinforced normal phenotype. Interferon-gamma induced adhesion was not associated with other interferon effects especially the anti-proliferative activity or modulation of surface antigens.
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PMID:Human interferon-gamma increases adhesion of cultured carcinoma cells to the substratum. 311 53

The correlation between the silver-stained nucleolar organizer region associated proteins (Ag-NORs) and the growth rate suppression (GRS) of ten established breast cancer cell lines which were treated with 4-hydroxy-tamoxifen (OHT) and interferon-gamma (g-IFN), respectively, was investigated by means of automated image analysis. Previous studies have shown a statistically significant relationship between the Ag-NOR quantity and the population doubling time (PDT) of these cell clones. The results of the present study showed a highly significant correlation between the GRS and the Ag-NOR quantity in estrogen receptor (ER) positive tumour cell lines after OHT treatment (P < 0.001) whereas no strict correlation of these parameters could be demonstrated after g-IFN treatment in both ER positive and negative cell lines. Our results suggest a different behaviour of NOR-proteins in breast cancer cell lines if treated either with g-IFN or OHT, probably reflecting the different mechanism of cell suppression mediated by OHT and g-IFN. It is concluded that quantitative assessment of Ag-NORs is not as suitable for the determination of the GRS as it is for the determination of cell duplication rates obtained on untreated tumour cell lines.
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PMID:Relationship between quantity of silver stained nucleolar organizer region associated proteins (Ag-NORs) and growth rate suppression of breast cancer cell lines after interferon-gamma and 4-hydroxy-tamoxifen treatment. 810 Jun 59

Combination of all-trans-retinoic acid (RA) with either interferon-alpha or -gamma resulted in a synergistic amplification of the anti-proliferative effect on cultured breast cancer cells. RA could be replaced by other biologically active retinoids. The synergism was also observed for the induction of 2'-5'-oligoadenylate synthetase, an enzyme which is involved in anti-viral activity of interferons and possibly in growth regulation of tumor cells. Combination of RA with interferon-gamma increased the down-regulation of specific binding sites for [125I]interferon-gamma. On the other hand interferons had no effect on the cytoplasmic binding protein for RA. Comparing all-trans- with 9-cis-RA, the latter was more effective in inhibiting tumor cell growth and in inducing synergism with interferon-gamma. This would indicate that retinoic X receptors are more important in mediating these effects than the RA receptors (RARs). This assumption is also supported by the failure of Ro-415253, a specific RAR-alpha antagonist, to reduce the synergistic interaction of RA with interferon with respect to growth inhibition.
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PMID:Mechanism of synergistic action of all-trans- or 9-cis-retinoic acid and interferons in breast cancer cells. 827 26

Current adoptive immunotherapy strategies in cancer patients require large numbers of activated T-cells and are limited by the availability of autologous tumour. We describe a novel method of T-cell activation that produced relatively rapid, high-fold expansion of stored, frozen lymphocytes obtained from the lymph nodes of 20 breast cancer patients during axillary dissection but does not require autologous tumour. In vitro exposure of thawed cells to bryostatin-1 (B), a non-tumour promoting protein kinase C activator and ionomycin (I), a calcium ionophore, at day 0 followed by culture in low dose interleukin-2 (IL-2 20 units ml-1) and restimulation again on day 10 results in 269-28,206 fold (geometric mean = 2254) expansion in cell numbers counted 17 days after initial stimulation. Analysis of cell surface markers revealed that B/I expanded human cells were predominantly T-cells (83-97%) and consisted of a mixture of CD8+ (46-74%) and CD4+ (4-30%) cells. B/I expanded cells did not lyse autologous tumour cells when tested in a 4-h 51Cr release assay, but murine studies reported previously have demonstrated specific and curative in vivo efficacy in MCA-105 tumour-bearing mice despite an inability to lyse autologous tumour in vitro. B/I expanded T-cells from five of six patients secreted the cytokines tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) in response to co-culture with autologous tumour cells but not with irrelevant tumour. These results are analogous to findings in a murine model, in which non-cytolytic B/I expanded T-cells mediated specific, curative anti-tumour effects in vivo, and lay the groundwork for a clinical trial of this novel strategy for the adoptive immunotherapy of breast cancer patients.
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PMID:Expansion and tumour specific cytokine secretion of bryostatin-activated T-cells from cryopreserved axillary lymph nodes of breast cancer patients. 830 69

The potentiating effects of human recombinant tumor necrosis factor-alpha (rTNF-alpha) on the antitumor actions of recombinant interferon-gamma (rIFN-gamma) and of natural interferons alpha and gamma combined (nIFN-alpha/nIFN-gamma) were studied on human breast cancer xenografts growing bilaterally in nude mice. The cytokines were injected singly or in combination in one of the two tumors of each mouse to study local effects while the opposite tumor was left undisturbed to evaluate systemic effects. The tumors received 20 intralesional injections (four cycles of 5 daily injections each). In injected tumors the best results were obtained with nIFN-alpha/nIFN-gamma supplemented with rTNF-alpha. The responses were dose dependent, resulting in complete regression of 9 of 9 tumors with rTNF-alpha used at the dose of 5 micrograms per injection, of 6 of 8 tumors at the dose of 2.5 micrograms, and of 4 of 8 tumors at the dose of 0.5 microgram. Mostly mild to moderate partial responses were seen in the other groups. The systemic effects on the contralateral tumors were significantly less than the local effects on the corresponding tumors. Histologically, responding tumors showed reactive fibrosis and inflammatory cell infiltration. No vascular alterations were seen, presumably because of the immunodeficiency of nude mice. It was concluded that the potentiation of the antitumor actions of IFNs by rTNF-alpha was effective at the local but not at the systemic level.
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PMID:Regression of human breast cancer xenografts in response to intralesional treatment with interferons alpha and gamma potentiated by tumor necrosis factor. 856 5

Retinoids and Interferons have been demonstrated to synergistically amplify the inhibition of proliferation in cultured breast cancer cells. Recently we reported that interferon-gamma (IFN-gamma) modulates the action of retinoic acid (RA): IFN-gamma increased expression of retinoic acid receptor-gamma (RAR-gamma) and suppressed the increase of retinoic acid binding protein type II (CRABP-II) expression. To improve the understanding of mechanism mediating synergism we extended our studies to the type I interferon-alpha. Synergistic inhibition of proliferation could be detected also by IFN-alpha and RA in BT-20 and SKBR-3 breast cancer cell lines but not in MCF-7 cells. Neither IFN-alpha nor any retinoid tested alone were able to increase RAR-gamma message, only the combination of both had this ability. In MCF-7 breast cancer cell lines the combination of any retinoid with IFN-alpha increased CRABP II expression level compared with the retinoids alone. In contrast with SKBR-3 and BT-20 cells a combination of ATRA with IFN-alpha markedly reduced ATRA mediated CRABP II induction. These results suggest that two factors may be responsible for synergistic action of RA and IFN-alpha: the inhibition of the CRABP II expression and an IFN-alpha/RA mediated upregulation of RAR-gamma.
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PMID:Interaction of retinoic acid and interferon-alpha in breast cancer cell lines. 861 38

Arginine-derived nitric oxide (NO) has been identified in some tumor cell lines and solid human tumors. The effect of tumor cell NO on tumor biology is poorly understood. The purpose of this study was to investigate the effect of NO production by EMT-6 murine breast cancer cells on tumor cell growth in vitro and subcutaneous tumor growth and experimental pulmonary metastasis in vivo. EMT-6 cells were incubated with endotoxin (LPS, 10 microgram/ml) and interferon-gamma (IFN, 50 U/ml), in the presence or absence of the NO synthase inhibitor, omega-nitro-L-arginine methyl ester (L-NAME, 2 mM), and NO production and cell number were assessed 24 hr later. EMT-6 cells were also treated overnight with LPS/IFN, in the presence or absence of L-NAME, washed and injected either subcutaneously in the dorsal flank (n = 40) or via the tail vein (n = 40) of syngeneic BALB/c mice. Two weeks following tumor cell injection, tumor size and number of pulmonary metastases were assessed. LPS/IFN stimulated NO production in EMT-6 cells and inhibited cell growth in vitro by 50%. L-NAME blocked LPS/IFN stimulation of NO production and restored cell growth to near control levels. When injected into BALB/c mice, LPS/IFN-stimulated tumor cells demonstrated a two-fold increase in subcutaneous tumor growth and experimental pulmonary metastases over control cells. L-NAME reduced tumor size and number of lung metastases to control levels, suggesting that tumor cell NO production was responsible for this effect. In summary, LPS/IFN-stimulated NO production in EMT-6 tumor cells inhibits tumor cell growth in vitro, yet paradoxically augments tumor growth and metastasis in vivo.
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PMID:Tumor cell nitric oxide inhibits cell growth in vitro, but stimulates tumorigenesis and experimental lung metastasis in vivo. 866 Nov 71

The escape of tumor cells from immune recognition is a central problem in tumor immunology. Here, we examined the functional role of somatic beta 2-microglobulin (beta2m) gene mutations in human lung and breast cancers. Using single-strand conformational polymorphism (SSCP) analysis and DNA sequencing, we found mutations in the beta2m gene in 2 of 110 tested lung, colon and breast tumors and tumor cell lines. No mutations were identified in 63 breast cancer tumors, in B-lymphoblastoid cell lines or normal tissues from these or other patients. In these cell lines, beta2m protein was undetectable by Western blot analysis and there was no MHC class I on their cell surface even after treatment with interferon-gamma. Transfection of these tumor cell lines with the beta2m gene, but not addition of purified beta2m protein restored MHC expression without addition of exogenous pepticles, indicating that endogenous beta2m expression is necessary for proper intracellular MHC assembly and stabilization by endogeneous pepticles. Mutation in beta2m caused cell line H2009 to be resistant to specific lysis by influenza virus-specific CTL from HLA matched donors, and transfection of the beta2m gene restored this killing. A small cell lung cancer cell line with low class I expression and with a normal beta2m genomic sequence nonetheless also demonstrated increased class I expression after transfection of the beta2m expression vector alone, indicating that the availability of beta2m may be rate limiting for MHC assembly in this line. Our results indicate that somatic mutations or selective loss of expression of the beta2m gene in human lung cancer is rare, but can cause defective MHC class I expression and function allowing these cells to escape recognition by cytotoxic T cells.
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PMID:Structural and functional analysis of beta2 microglobulin abnormalities in human lung and breast cancer. 882 45


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