Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Classical and molecular immunological means of active tumor-specific immunization against human cancers yielded whole cell or tumor cell lysate vaccines of preventive value (reduced relapse rates) and dendritic cell-peptide or genetically engineered vaccines that may induce remissions even in metastatic disease. Active tumor-specific immunization was often successful in the past 50 years against experimental tumors maintained in the laboratory. During the epochs of classical and molecular immunology several vaccines were generated and used for the reduction of relapse rates of human cancer after surgical removal of the primary or metastatic tumors. Whole cell vaccines consist of X-irradiated autologous or allogeneic tumor cells coadministered with immunostimulants (BCG, Detox). Tumor cells haptenized biologically (as in viral oncolysates) or chemically were also used. Dendritic cell vaccines are prepared by transfection or transduction with tumor antigen-encoding DNA or by pulsing the cells with antigenic peptides in vitro; or collecting dendritic cells that engulfed apoptotic tumor cell DNA and/or peptide antigens in vivo for reinjection into the patient. Genetically engineered tumor cells are prepared in vitro to express MHC and peptides, costimulatory molecules (B7.1) and cyto- or lymphokines (interferons, interleukins, hematopoietic growth factors) for vaccination of patients. Antibody- and immune T cell-mediated immune reactions to autologous tumor cells are newly generated and/or quantitatively increased in immunized patients but do not always correlate with clinical response. Most vaccines are claimed to have reduced relapse rates presumably by inducing effective host immunity against micrometastases. Dendritic cell-peptide vaccines could induce partial or occasionally complete remissions in metastatic disease. The wrong antigenic presentation may result in tolerance induction toward the tumor; occasionally tumor enhancement may occur. Human tumor antigens when presented appropriately (with costimulatory molecules and with IL-2, IL-12) break the host's natural tolerance toward its tumor and induce rejection strength immune reactions even in patients with metastatic disease. Immune T cells thus generated could be collected for adoptive immunotherapy. For successful active specific immunization against human cancers the understanding of the immunoevasive maneuvers of the tumor cell (through FasL --> Fas; TRAIL; CD40L --> CD40; TGFbeta etc. systems) is essential.
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PMID:Vaccination against human cancers (review). 1060 52

The role of endogenous NO on cell survival was investigated in human melanoma cells and melanocytes. Inducible NO synthase (iNOS) was always expressed in a panel of melanoma cell lines from metastatic lesions and in normal adult melanocytes. iNOS was also detected by immunohistochemistry in melanoma cells from metastases. Release of NO by tumor cells and melanocytes was inhibited by a specific iNOS inhibitor, aminoguanidine (AMG). Inhibition of endogenous NO synthesis did not affect cell cycle progression of melanoma cells but led to cell death by apoptosis, as indicated by Annexin V/propidium iodide and terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling assays. By contrast, iNOS inhibition by AMG did not promote apoptosis in normal adult melanocytes. A mitochondrial pathway was involved in melanoma apop tosis, as indicated by altered mitochondrial membrane potential (delta psi(m)) and down-regulation of Bcl-2 protein level after iNOS inhibition. AMG treatment triggered release of caspase-1, enzymatic activation of caspase-3, and degradation of poly(ADP-ribose) polymerase, one of the main caspase-3 substrates. Melanoma cell apoptosis induced by iNOS inhibition was completely blocked by peptide inhibitors of caspase-1 and caspase-3 (Ac-DEVD-CHO and AC-YVAD-CHO) or by an exogenous NO donor, sodium nitroprusside, or by addition of serum. Finally, comparison of control and AMG-treated melanoma cells by pathway-specific gene array analysis indicated that inhibition of NO synthesis led, before induction of apoptosis, to up-regulation of mRNA levels of genes involved in the apoptosis pathway such as Bax, caspase-1, caspase-3, caspase-6, gadd45beta, mdm2, and TRAIL. Taken together, these results indicate that melanoma cell survival is regulated by endogenous NO resulting from iNOS activity.
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PMID:Antiapoptotic role of endogenous nitric oxide in human melanoma cells. 1119 80

In order to form distant metastases, cells from the primary tumor have to detach, enter the blood- or lymph-compartment and escape immune surveillance. Here, we describe the selection of rat colon carcinoma cell lines (CC531s-m1 and CC531s-m2) that escaped from systemic immune surveillance; CC531s cells were injected into the v. jugularis of Wag/Rij rats, after three weeks the lung tumors were isolated, the tumor cells were cultured, characterized and injected again. The m1- and m2-cell lines were less susceptible for killing by syngeneic NK cells. Further characterization of this cell line showed a decreased sensitivity towards TRAIL- and CD95L-, but not to granzyme B-mediated apoptosis. In the m1- and m2-cells log-phase growth started earlier as compared to the parental cell line, whereas no changes were found in anchorage-dependent or anchorage-independent growth. After subcapsular injection of the m2-cell line into the liver of rats much more lung metastases were formed in comparison to injection of the parental cell line. In conclusion, the results suggest that the resistance of the m1- and m2-cells to NK cell-mediated apoptosis was associated with their capability to survive systemic immune surveillance and form metastases in vivo.
Clin Exp Metastasis 2003
PMID:Rat colon carcinoma cells that survived systemic immune surveillance are less sensitive to NK-cell mediated apoptosis. 1471 5

The majority of colorectal cancers have lost/inactivated the p53 tumor suppressor gene. Using isogenic human colon cancer cells that differ only in their p53 status, we demonstrate that loss of p53 renders tumor cells relatively resistant to the topoisomerase I inhibitor, irinotecan. Whereas irinotecan-induced up-regulation of the proapoptotic proteins PUMA and Noxa requires p53, we find that irinotecan inhibits Janus kinase 2 (JAK2)-signal transducer and activator of transcription 3 and 5 (STAT3/5) signaling in both p53-proficient and p53-deficient tumor cells. We show that irinotecan inhibits JAK2-STAT3/5-dependent expression of survival proteins (Bcl-x(L) and XIAP) and cooperates with Apo2 ligand/tumor necrosis factor-related apoptosis-inducing ligand (Apo2L/TRAIL) to facilitate p53-independent apoptosis of colon cancer cells. Whereas xenografts of p53-deficient colon cancer cells are relatively resistant to irinotecan compared with their p53-proficient counterparts, combined treatment with irinotecan and Apo2L/TRAIL eliminates hepatic metastases of both p53-proficient and p53-deficient cancer cells in vivo and significantly improves the survival of animals relative to treatment with either agent alone. Although the synergy between chemotherapy and Apo2L/TRAIL has been ascribed to p53, our data demonstrate that irinotecan enhances Apo2L/TRAIL-induced apoptosis of tumor cells via a distinct p53-independent mechanism involving inhibition of JAK2-STAT3/5 signaling. These findings identify a novel p53-independent channel of cross-talk between topoisomerase I inhibitors and Apo2L/TRAIL and suggest that the addition of Apo2L/TRAIL can improve the therapeutic index of irinotecan against both p53-proficient and p53-deficient colorectal cancers, including those that have metastasized to the liver.
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PMID:Elimination of hepatic metastases of colon cancer cells via p53-independent cross-talk between irinotecan and Apo2 ligand/TRAIL. 1560 80

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL, APO-2L) is a mediator of cell death that preferentially targets cancer cells. The potential of TRAIL as a chemotherapeutic agent is limited, however, because of the emergence of TRAIL resistance. Furthermore, recent studies have demonstrated that alternative TRAIL signaling is unmasked in TRAIL resistant cells. In these cells, the predominant effect of TRAIL receptor activation is the activation of nuclear factor-kappaB (NF-kappaB), which promotes tumor metastases and invasion. TRAIL resistance can occur at the level of the death inducing signaling complex via upregulation of cFLIP or via an increase in antiapoptotic proteins of the Bcl-2 family. A paradigm emerges from this information, that chemotherapy, targeting NF-kappaB, cFLIP, or antiapoptotic proteins of the Bcl-2 family, in combination with TRAIL maybe more rational than TRAIL therapy alone.
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PMID:TRAIL resistance results in cancer progression: a TRAIL to perdition? 1678 86

Prostate cancers frequently metastasize to the skeleton, and it has been hypothesized that this environment selectively supports the growth of these tumours. Specifically there is strong evidence that interactions between tumour cells and BMSCs (bone marrow stromal cells) play a major role in supporting prostate cancer growth and survival in bone. Here, we examine factors shown to be secreted by BMSCs, such as IGFs (insulin-like growth factors) and IL-6 (interleukin 6), shown to promote prostate cancer cell proliferation and to potentially replace the requirement for androgens. In addition we discuss another factor produced by BMSCs, osteoprotegerin, which may promote tumour cell survival by suppressing the biological activity of the pro-apoptotic ligand TRAIL (tumour-necrosis-factor-related apoptosis-inducing ligand).
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PMID:Bone marrow stromal cells promote growth and survival of prostate cancer cells. 1763 26

Raf-1 kinase inhibitor protein (RKIP) has been implicated in the regulation of cell survival pathways and metastases, and is poorly expressed in tumors. We have reported that the NF-kappaB pathway regulates tumor resistance to apoptosis by the TNF-alpha family via inactivation of the transcription repressor Yin Yang 1 (YY1). We hypothesized that RKIP overexpression may regulate tumor sensitivity to death ligands via inhibition of YY1 and up-regulation of death receptors (DRs). The TRAIL-resistant prostate carcinoma PC-3 and melanoma M202 cell lines were examined. Transfection with CMV-RKIP, but not with control CMV-EV, sensitized the cells to TRAIL-mediated apoptosis. Treatment with RKIP small interfering RNA (siRNA) inhibited TRAIL-induced apoptosis. RKIP overexpression was paralleled with up-regulation of DR5 transcription and expression; no change in DR4, decoy receptor 1, and decoy receptor 2 expression; and inhibition of YY1 transcription and expression. Inhibition of YY1 by YY1 siRNA sensitized the cells to TRAIL apoptosis concomitantly with DR5 up-regulation. RKIP overexpression inhibited several antiapoptotic gene products such as X-linked inhibitor of apoptosis (XIAP), c-FLIP long, and Bcl-x(L) that were accompanied with mitochondrial membrane depolarization. RKIP overexpression in combination with TRAIL resulted in the potentiation of these above effects and activation of caspases 8, 9, and 3, resulting in apoptosis. These findings demonstrate that RKIP overexpression regulates tumor cell sensitivity to TRAIL via inhibition of YY1, up-regulation of DR5, and modulation of apoptotic pathways. We suggest that RKIP may serve as an immune surveillance cancer gene, and its low expression or absence in tumors allows the tumor to escape host immune cytotoxic effector cells.
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PMID:Regulation of tumor cell sensitivity to TRAIL-induced apoptosis by the metastatic suppressor Raf kinase inhibitor protein via Yin Yang 1 inhibition and death receptor 5 up-regulation. 1791 31

High intake of whole grain food has been suggested as an important factor for reducing the risk of colon cancer, owing to the abundance of indigestible fibers. Our findings demonstrated that, among various rice bran phenolic compounds tested, cycloartenyl ferulate (CF) showed the most prominent in vitro growth inhibition on human colorectal adenocarcinoma SW480, but had low toxicity on normal colon CCD-18-Co cells. The anticancer activity of CF was further illustrated by its ability to induce significant regression of SW480 xenograft in nude mice. CF elevated the death receptors DR4 and DR5 and triggered both the death receptor and the mitochondrial apoptosis pathways. Depletion of anti-apoptotic Bcl-2 and up-regulation of pro-apoptotic Bak were observed, accompanied by dissipation of the mitochondrial membrane potential and release of cyto c and SMAC/DIABLO from mitochondria into the cytosol. Bid was found to be cleaved by caspase-8, so that the death receptor pathway might be exaggerated by the mitochondrial pathway. Strikingly, we showed for the first time that CF also sensitized the metastatic and resistant colon cancer SW620 to TRAIL-induced apoptosis and the mechanisms involved at least enhanced activation of caspase-8 and -3. This study provides a clear evidence that the health-beneficial properties of whole grain consumption are not only limited by the presence of dietary fibers but also other molecules that can either act as a chemopreventive agent to directly induce tumor regression or as a sensitizer to enhance TRAIL-induced apoptosis in metastatic cancer cells.
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PMID:A rice bran polyphenol, cycloartenyl ferulate, elicits apoptosis in human colorectal adenocarcinoma SW480 and sensitizes metastatic SW620 cells to TRAIL-induced apoptosis. 1942 86

The members of the tumour necrosis factor (TNF) superfamily of cytokines play important roles in the regulation of various immune-cell functions. Likewise, induction of cell death by apoptosis is indispensable for the normal functioning of the immune system. There are two major pathways of apoptosis induction. The intrinsic, or mitochondrial, pathway is regulated by the activation and interaction of members of the Bcl-2 family. The extrinsic, or death receptor, pathway is triggered by certain TNF family members when they engage their respective cognate receptors on the surface of the target cell. Hence, cell-to-cell-mediated death signals are induced by activation of these death receptor-ligand systems. Besides TNF itself and the CD95 (Fas/APO-1) ligand (FasL/Apo1L), the TNF-related apoptosis-inducing ligand (TRAIL/Apo2L) belongs to the subfamily of ligands that is responsible for extrinsic induction of cell death. Depending on their status of stimulation, TRAIL can be expressed by various cells of the immune system, amongst them natural killer (NK) cells, T cells, natural killer T cells (NKT cells), dendritic cells and macrophages. TRAIL has been implicated in immunosuppressive, immunoregulatory and immune-effector functions. With respect to pathological challenges, TRAIL and its receptors have been shown to play important roles in the immune response to viral infections and in immune surveillance of tumours and metastases. In this review we summarize the current knowledge on the role of TRAIL and its receptors in the immune system and, based on this, we discuss future directions of research into the diverse functions of this fascinating receptor-ligand system.
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PMID:Following TRAIL's path in the immune system. 1947 10

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) induces apoptosis in MIT6 cells derived from primary oral squamous cell carcinoma (OSCC), whereas it does not induce apoptosis in MIL6 cells derived from metastases. The present studies were performed to examine whether activation of c-Jun NH2-terminal kinase (JNK) is implicated in the differential sensitivity to TRAIL-induced apoptosis. The TRAIL-induced JNK activation in MIT6 cells was stronger than in MIL6 cells, as assessed by Western blotting using antibodies specific for phospho-JNK. To evaluate the role of JNK1 in TRAIL-induced cell death, one clone expressing the dominant-negative form of JNK1 (dnJNK1) was established. The dnJNK1-expressing cells and MIL6 cells expressed TRAIL protein at levels similar to or even greater than MIT6 cells did. When cell death was assessed by annexin V staining and mitochondrial membrane potential, kinetic studies demonstrated that the dnJNK1-expressing cells were substantially more resistant to 100 ng/ml TRAIL, comparable to MIL6 cells, at 36 and 48 h after stimulation. Collectively, the primary OSCC cell line, MIT6, is sensitive to TRAIL but its metastatic line MIL6 is resistant to TRAIL exposure. Thus, the underlying molecular mechanism of TRAIL-induced cell death involves JNK activation. These results suggest that the acquisition of TRAIL resistance provides some metastatic capacity to primary tumors.
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PMID:Tumor necrosis factor-related apoptosis-inducing ligand induces apoptotic cell death through c-Jun NH2-terminal kinase activation in squamous cell carcinoma cells. 1978 36


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