Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0033036 (APC)
 10,214 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The cooked meat mutagen 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) produces tumors at multiple sites in the F344 rat, including adenocarcinomas of the colon. In the present study, the development of IQ-induced colorectal tumors was shown to be accompanied by the progressive inhibition of programmed cell death. This was associated with increased expression of the antiapoptosis protein Bcl-2 and decreased expression of bax, a known activator of apoptosis. Carcinomas bearing high levels of bcl-2 expression exhibited low levels of p53, the tumor suppressor protein that in some circumstances has been shown to down-regulate bcl-2. Because they lack mutations in the genes commonly associated with increased cell proliferation (APC, Ki-ras, and p53) and show no evidence of microsatellite instability, IQ-induced colon tumors might arise via the deregulation of bcl-2 expression, leading to inhibition of programmed cell death.
 ...
PMID:Inhibition of apoptosis in colon tumors induced in the rat by 2-amino-3-methylimidazo[4,5-f]quinoline. 881 12

The Bcl-2 homologue, Bak, is a potent inducer of apoptosis. FISH data presented here located the gene to 6p21.3. Mapping was consistent with its location centromeric of the HSET locus and approximately 400kb from the MHC. The construction of a contig of genomic clones across the locus facilitated the sequencing of a PAC containing the gene. Comparison of the gene structure to functional and physical domains revealed a good agreement between the physical structure and the intron-exon organisation. The position of a single intron was conserved in comparison to other members of the Bcl-2 family, namely Bax, CED-9, Bcl-X and Bcl-2, but all other introns were displaced, consistent with a divergent phylogeny.
 ...
PMID:Genomic structure and domain organisation of the human Bak gene. 957 42

The beclin 1 (BECN1) gene encodes a 60-kDa coiled-coil protein that interacts with the prototypic apoptosis inhibitor Bcl-2. Previous studies indicate that beclin 1 maps to a region approximately 150 kb centromeric to BRCA1 on chromosome 17q21 that is commonly deleted in breast, ovarian, and prostate cancer. The complete cDNA sequence of beclin 1 encodes a 2098-bp transcript, with a 120-bp 5' UTR, 1353-bp coding region, and 625-bp 3' UTR. Hybridization screening of a human genomic PAC library identified PAC 452O8, which contains the complete beclin 1 gene. Determination of the exon-intron structure of beclin 1 reveals 12 exons, ranging from 61 to 794 bp, which extend over 12 kb of the human genome. FISH analysis of human breast carcinoma cell lines using PAC 452O8 as probe identified allelic beclin 1 deletions in 9 of 22 cell lines. Sequencing of genomic DNA from 10 of these cell lines revealed no mutations in coding regions or splice junctions. Additionally, Northern blot analysis of 11 cell lines did not identify any abnormalities in beclin 1 transcripts. These results indicate that human breast carcinoma cell lines frequently contain allelic deletions of beclin 1, but not beclin 1 coding mutations.
 ...
PMID:Cloning and genomic organization of beclin 1, a candidate tumor suppressor gene on chromosome 17q21. 1039

Human protein C is a natural anticoagulant factor, and a recombinant activated form of the molecule (rhAPC) is completing clinical evaluation for treatment of severe sepsis. Because of the pathophysiologic role of endothelial dysfunction in severe inflammatory disease and sepsis, we explored the possibility that rhAPC might directly modulate endothelial function, independent of its anticoagulant activity. Using broad transcriptional profiling, we show that rhAPC directly modulates patterns of endothelial cell gene expression clustering into anti-inflammatory and cell survival pathways. rhAPC directly suppressed expression of p50 and p52 NFkappaB subunits, resulting in a functional decrease in NFkappaB binding at target sites. Further, rhAPC blocked expression of downstream NFkappaB regulated genes following tumor necrosis factor alpha induction, including dose-dependent suppression of cell adhesion expression and functional binding of intracellular adhesion molecule 1, vascular cell adhesion molecule 1, and E-selectin. Further, rhAPC modulated several genes in the endothelial apoptosis pathway, including the Bcl-2 homologue protein and inhibitor of apoptosis protein. These pathway changes resulted in the ability of rhAPC to inhibit the induction of apoptosis by the potent inducer, staurosporine. This new mechanistic understanding of endothelial regulation and the modulation of tumor necrosis factor-induced endothelial dysfunction creates a novel link between coagulation, inflammation, and cell death and provides insight into the molecular basis for the efficacy of APC in systemic inflammation and sepsis.
 ...
PMID:Gene expression profile of antithrombotic protein c defines new mechanisms modulating inflammation and apoptosis. 1127 52

Observations support the theory that development of left- and right-sided colorectal cancers may involve different mechanisms. This study investigated different genes involved in oncogenesis of colon and rectal cancers and analysed their prognostic value. The study group comprised 35 colon and 42 rectal cancers. Rectal cancer patients had been treated with standardized surgery performed by an experienced rectal cancer surgeon. Mutation analysis was performed for p53 in eight colon cancers and for APC and p53 in 22 rectal cancers. MLH1, MSH2, Bcl-2, p53, E-cadherin and beta-catenin were investigated by immunohistochemistry in all colorectal tumours. APC mutation analysis of the MCR showed truncating mutations in 18 of 22 rectal tumours (82%), but the presence of an APC mutation was not related to nuclear beta-catenin expression (p=0.75). Rectal cancers showed significantly more nuclear beta-catenin than colon cancers (65% versus 40%, p=0.04). p53 mutation analysis corresponded well with p53 immunohistochemistry (p<0.001). Rectal cancers showed significantly more immunohistochemical expression of p53 than colon cancers (64% versus 29%, p=0.003). In rectal cancers, a significant correlation was found between positive p53 expression and worse disease-free survival (p=0.008), but not in colon cancers. Cox regression showed that p53-expression (p=0.03) was an independent predictor for disease-free survival in rectal cancers. This study concluded that rectal cancer may involve more nuclear beta-catenin in the APC/beta-catenin pathway than colon cancer and/or nuclear beta-catenin may have another role in rectal cancer independently of APC. The p53-pathway seems to be more important in rectal cancer, in which it also has independent prognostic value. When prognostic markers are investigated in larger series, differences in biological behaviour between colon and rectal cancer should be considered.
 ...
PMID:Mechanisms of oncogenesis in colon versus rectal cancer. 1159 95

Colon cancer is the third most common cancer globally. The risk of developing colon cancer is influenced by a number of factors that include age and diet, but is primarily a genetic disease, resulting from oncogene over-expression and tumour suppressor gene inactivation. The induction and progression of the disease is briefly outlined, as are the cellular changes that occur in its progression. While colon cancer is uniformly amenable to surgery if detected at the early stages, advanced carcinomas are usually lethal, with metastases to the liver being the most common cause of death. Oncogenes and genetic mutations that occur in colon cancer are featured. The molecules and signals that act to eradicate or initiate the apoptosis cascade in cancer cells, are elucidated, and these include caspases, Fas, Bax, Bid, APC, antisense hTERT, PUMA, 15-LOX-1, ceramide, butyrate, tributyrin and PPARgamma, whereas the molecules which promote colon cancer cell survival are p53 mutants, Bcl-2, Neu3 and COX-2. Cancer therapies aimed at controlling colon cancer are reviewed briefly.
 ...
PMID:Colon cancer: genomics and apoptotic events. 1525 76

Familial adenomatous polyposis patients, who have a germline APC mutation, develop adenomas in normal-appearing colonic mucosa, and in the process usually acquire a mutation in the other APC allele as well. Nonetheless, the cellular mechanisms that link these initiating genetic changes with the earliest tissue changes (upward shift in the labeling index) in colon tumorigenesis are unclear. Based on the tenet that colorectal cancer originates from crypt stem cells (SCs) and on our kinetic modeling, we hypothesized that overpopulation of mutant colonic SCs is the missing link. Directly testing this hypothesis requires measuring changes in the size of the SC population, but specific markers for human colonic SCs are lacking. Hence, we used immunohistochemical mapping to study crypt base cells, of which SCs are a subset. Using colectomy specimens from 16 familial adenomatous polyposis and 11 control cases, we determined the topographic profiles of various cell populations along the crypt axis and the proportions of each cell type. In the formation of adenomatous crypts, the distribution of cells expressing crypt base cell markers (MSH2, Bcl-2, survivin) expanded toward the crypt surface and showed the greatest proportional increase (fivefold to eightfold). Cells expressing a marker for the upper crypt (p27(kip1)) shifted to the crypt bottom and showed the smallest increase. This suggests that: 1) during adenoma development, APC mutations cause expansion of the crypt base cell population, including crypt SCs; 2) SC overpopulation can explain the shifts in pattern of proliferative crypt cell populations in early colon tumorigenesis, and 3) mutant crypt SCs clonally expand to form colonic adenomas and carcinomas.
 ...
PMID:Colonic crypt changes during adenoma development in familial adenomatous polyposis: immunohistochemical evidence for expansion of the crypt base cell population. 1550 20

Although IL-10 acts as an inhibitory cytokine for APC and CD4(+) T cell function, its effects on CD8(+) T cells are unclear. Additionally, little is known about whether initial priming in the presence of IL-10 can have long-lasting effects and influence subsequent CD8(+) T cell responses that occur in the absence of the cytokine. In the present study, we clarified the role of IL-10 during primary responses and examined whether exposure to IL-10 during initial priming of CD8(+) T cells impacted secondary responses. To determine the effect of IL-10 on Ag-specific T cell responses, peptide-pulsed IL-10R2(-/-) splenic dendritic cells were used to prime T cells from OT-I CD8(+) TCR transgenic mice. During the primary response, the presence of IL-10 resulted in enhancement of CD8(+) T cell numbers without detectable alterations in the kinetics or percentage of cells that underwent proliferation. A modest increase in survival, not attributable to Bcl-2 or Bcl-x(L), was also observed with IL-10 treatment. Other parameters of CD8(+) T cell function, including IL-2, IFN-gamma, TNF-alpha, and granzyme production, were unaltered. In contrast, initial exposure to IL-10 during the primary response resulted in decreased OT-I expansion during secondary stimulation. This was accompanied by lowered IL-2 levels and reduced percentages of proliferating BrdU(+) cells and OT-I cells that were CD25(high). IFN-gamma, TNF-alpha, and granzyme production were unaltered. These data suggest that initial exposure of CD8(+) T cells to IL-10 may be temporarily stimulatory; however, programming of the cells may be altered, resulting in diminished overall responses.
 ...
PMID:Priming in the presence of IL-10 results in direct enhancement of CD8+ T cell primary responses and inhibition of secondary responses. 1584 36

Research on developing molecular diagnostics for hereditary cancers resulted in establishing diagnostic services for familiar polyposis and non-polyposis patients (mutation determination of APC, MYH, STK11, SMAD4, MLH1, MSH2). In familiar testicular cancers the role of gr/gr gene on Y chromosome was identified. Molecular diagnostic tool was established to monitor the progression of follicular lymphoma using Bcl-2/IgH fusion sequences. Molecular diagnostic tools were developed to monitor circulating endothelial precursor cells (CEP) as well and the technique was tested in lung cancer patients. In malignant melanoma we have tested several potential novel markers among which ryanodine receptor seems to be a promising one, while the functional P2X7 receptor may serve as a therapeutic target. We have determined the tyrosine kinase "kinome" profile of HER-2-amplified breast cancers. Furthermore, the "kinome" profile was found to be characteristic for head and neck cancers of various anatomical location. Based on previous studies on the anti-migratory and antimetastatic potential of low-molecular-weight heparins, we have identified short heparin-derived oligosaccharides with maintained antimetastatic- but non-anticoagulant potentials. Pharmacogenomic studies on the role of polymorphism of the serine-hydroxymethyl-transferase (SHMT) gene in the efficacy of 5-FU and FOLFIRI protocols of colorectal cancer patients revealed a significant effect resulting in altered overall survival as well.
 ...
PMID:[Developments in cancer management by innovative genomics. 2006 report of the National Cancer Consortium]. 1721 11

The intracellular signaling pathways mediating the neurotrophic actions of pituitary adenylate cyclase-activating polypeptide (PACAP) were investigated in human neuroblastoma SH-SY5Y cells. Previously, we showed that SH-SY5Y cells express the PAC(1) and VIP/PACAP receptor type 2 (VPAC(2)) receptors, and that the robust cAMP production in response to PACAP and vasoactive intestinal peptide (VIP) was mediated by PAC(1) receptors (Lutz et al. 2006). Here, we investigated the ability of PACAP-38 to differentiate SH-SY5Y cells by measuring morphological changes and the expression of neuronal markers. PACAP-38 caused a concentration-dependent increase in the number of neurite-bearing cells and an up-regulation in the expression of the neuronal proteins Bcl-2, growth-associated protein-43 (GAP-43) and choline acetyltransferase: VIP was less effective than PACAP-38 and the VPAC(2) receptor-specific agonist, Ro 25-1553, had no effect. The effects of PACAP-38 and VIP were blocked by the PAC(1) receptor antagonist, PACAP6-38. As observed with PACAP-38, the adenylyl cyclase activator, forskolin, also induced an increase in the number of neurite-bearing cells and an up-regulation in the expression of Bcl-2 and GAP-43. PACAP-induced differentiation was prevented by the adenylyl cyclase inhibitor, 2',5'-dideoxyadenosine (DDA), but not the protein kinase A (PKA) inhibitor, H89, or by siRNA-mediated knock-down of the PKA catalytic subunit. PACAP-38 and forskolin stimulated the activation of extracellular signal-regulated kinase (ERK), mitogen-activated protein kinase (MAP; p38 MAP kinase) and c-Jun N-terminal kinase (JNK). PACAP-induced neuritogenesis was blocked by the MEK1 inhibitor PD98059 and partially by the p38 MAP kinase inhibitor SB203580. Activation of exchange protein directly activated by cAMP (Epac) partially mimicked the effects of PACAP-38, and led to the phosphorylation of ERK but not p38 MAP kinase. These results provide evidence that the neurotrophic effects of PACAP-38 on human SH-SY5Y neuroblastoma cells are mediated by the PAC(1) receptor through a cAMP-dependent but PKA-independent mechanism, and furthermore suggest that this involves Epac-dependent activation of ERK as well as activation of the p38 MAP kinase signaling pathway.
 ...
PMID:PACAP-38 induces neuronal differentiation of human SH-SY5Y neuroblastoma cells via cAMP-mediated activation of ERK and p38 MAP kinases. 1799 38


1 2 3 4 Next >>