Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038362 (stomatitis)
 8,852 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have studied the role of a previously described tubulovesicular compartment near the cis-Golgi apparatus in endoplasmic reticulum (ER)-to-Golgi protein transport by light and immunoelectron microscopy in Vero cells. The compartment is defined by a 53-kDa transmembrane protein designated p53. When transport of the vesicular stomatitis virus strain ts045 G protein was arrested at 39.5 degrees C, the G protein accumulated in the ER but had access to the p53 compartment. At 15 degrees C, the G protein was exported from the ER into the p53 compartment which formed a compact structure composed of vesicular and tubular profiles in close proximity to the Golgi. Upon raising the temperature to 32 degrees C, the G protein migrated through the Golgi apparatus while the p53 compartment resumed its normal structure again. These results establish the p53 compartment as the 15 degrees C intermediate of the ER-to-Golgi protein transport pathway.
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PMID:Identification of an intermediate compartment involved in protein transport from endoplasmic reticulum to Golgi apparatus. 196 13

Microinjection of antibodies against a synthetic peptide of a non-clathrin-coated vesicle-associated coat protein, beta-COP, blocks transport of a temperature-sensitive vesicular stomatitis virus glycoprotein (ts-O45-G) to the cell surface. Transport is inhibited upon release of the viral glycoprotein from temperature blocks at 39.5 degrees C (endoplasmic reticulum [ER]) and 15 degrees C (intermediate compartment), but not at 20 degrees C (trans-Golgi network). Ts-O45-G is arrested in tubular membrane structures containing p53 at the interface of the ER and the Golgi stack. This is consistent with inhibition of acquisition of endoglycosidase H resistance of ts-O45-G in injected cells. Secretion of endogenous proteins and maturation of cathepsin D are also inhibited. These data provide in vivo evidence that beta-COP has an important function in biosynthetic membrane traffic in mammalian cells.
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PMID:Beta-COP is essential for biosynthetic membrane transport from the endoplasmic reticulum to the Golgi complex in vivo. 833 7

p53/58 is a transmembrane protein that continuously recycles between the ER and pre-Golgi intermediates composed of vesicular-tubular clusters (VTCs) found in the cell periphery and at the cis face of the Golgi complex. We have generated an antibody that uniquely recognizes the p53/58 cytoplasmic tail. Here we present evidence that this antibody arrests the anterograde transport of vesicular stomatitis virus glycoprotein and leads to the accumulation of p58 in pre-Golgi intermediates. Consistent with a role for the KKXX retrieval motif found at the cytoplasmic carboxyl terminus of p53/58 in retrograde traffic, inhibition of transport through VTCs correlates with the ability of the antibody to block recruitment of COPI coats to the p53/58 cytoplasmic tail and to p53/58-containing membranes. We suggest that p53/58 function may be required for the coupled exchange of COPII for COPI coats during segregation of anterograde and retrograde transported proteins.
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PMID:p53/58 binds COPI and is required for selective transport through the early secretory pathway. 915 66

Rab2 immunolocalizes to pre-Golgi intermediates (vesicular-tubular clusters [VTCs]) that are the first site of segregation of anterograde- and retrograde-transported proteins and a major peripheral site for COPI recruitment. Our previous work showed that Rab2 Q65L (equivalent to Ras Q61L) inhibited endoplasmic reticulum (ER)-to-Golgi transport in vivo. In this study, the biochemical properties of Rab2 Q65L were analyzed. The mutant protein binds GDP and GTP and has a low GTP hydrolysis rate that suggests that Rab2 Q65L is predominantly in the GTP-bound-activated form. The purified protein arrests vesicular stomatitis virus glycoprotein transport from VTCs in an assay that reconstitutes ER-to-Golgi traffic. A quantitative binding assay was used to measure membrane binding of beta-COP when incubated with the mutant. Unlike Rab2 that stimulates recruitment, Rab2 Q65L showed a dose-dependent decrease in membrane-associated beta-COP when incubated with rapidly sedimenting membranes (ER, pre-Golgi, and Golgi). The mutant protein does not interfere with beta-COP binding but stimulates the release of slowly sedimenting vesicles containing Rab2, beta-COP, and p53/gp58 but lacking anterograde grade-directed cargo. To complement the biochemical results, we observed in a morphological assay that Rab2 Q65L caused vesiculation of VTCs that accumulated at 15 degrees C. These data suggest that the Rab2 protein plays a role in the low-temperature-sensitive step that regulates membrane flow from VTCs to the Golgi complex and back to the ER.
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PMID:A Rab2 mutant with impaired GTPase activity stimulates vesicle formation from pre-Golgi intermediates. 1035

We investigated the role of endogenous AP-1 in human tumor cell lines by introducing SupJunD-1, a dominant-negative mutant of AP-1, using vesicular stomatitis virus G protein (VSV-G)-pseudotyped retrovirus vectors. Single inoculation of six human tumor cell lines, originating from osteosarcomas, non-small cell lung carcinomas or cervical carcinomas, with recombinant SupJunD-1 virus at a high multiplicity of infection readily inhibited colony formation in soft agar. We detected no significant changes in expression levels of AP-1 components c-Jun or Fra-1, adhesion molecules CD44 or E-cadherin, or cell cycle regulator p53, which are encoded by genes previously reported to be under the control of AP-1 in some mouse or human cell lines. By varying the dosage of VSV-G-pseudotyped retrovirus, we were able to change the proviral copy number of supjunD-1 from 1 to approximately 10 and monitor suppression of endogenous AP-1 function as assessed by growth characteristics of the tumor cell lines, we found a SupJunD-1 dosage which significantly suppressed anchorage-independent growth without affecting the cellular growth in monolayer cultures at all. We conclude that endogenous AP-1 levels necessary for oncogenic activity are much higher than those sufficient to support normal growth.
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PMID:Endogenous AP-1 levels necessary for oncogenic activity are higher than those sufficient to support normal growth. 1107 61

We have recently shown that vesicular stomatitis virus (VSV) exhibits potent oncolytic activity both in vitro and in vivo (S. Balachandran and G. N. Barber, IUBMB Life 50:135-138, 2000). In this study, we further demonstrated, in vivo, the efficacy of VSV antitumor action by showing that tumors that are defective in p53 function or transformed with myc or activated ras are also susceptible to viral cytolysis. The mechanism of viral oncolytic activity involved the induction of multiple caspase-dependent apoptotic pathways was effective in the absence of any significant cytotoxic T-lymphocyte response, and occurred despite normal PKR activity and eIF2alpha phosphorylation. In addition, VSV caused significant inhibition of tumor growth when administered intravenously in immunocompetent hosts. Our data indicate that VSV shows significant promise as an effective oncolytic agent against a wide variety of malignant diseases that harbor a diversity of genetic defects.
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PMID:Oncolytic activity of vesicular stomatitis virus is effective against tumors exhibiting aberrant p53, Ras, or myc function and involves the induction of apoptosis. 1123 74

The human homolog of KET, p63, bears strong homology to the tumor suppressor p53 and plays an essential role in epithelial development. CUSP, the most abundant cutaneous product of p63, has been identified as an autoantigen in chronic ulcerative stomatitis (CUS). The original report of KET expression at least partially contradicts p63 expression subsequently reported by many different groups. We have examined p63 expression by Northern analysis of RNA from multiple human tissues and by indirect immunofluorescence of rat tissue with CUS patient sera. Northern analysis reveals p63 RNA in skin, thymus, placenta, skeletal muscle, kidney, and lung, with non-transactivating p63 RNA in skin, thymus, and placenta. Reverse transcriptase polymerase chain reaction (rtPCR) assays show abundant non-transactivating p63 RNA, and little to no transactivating p63 RNA, in human basal cell carcinoma as well as in normal skin adjacent to the tumors. p63 RNA expression was not detected in brain, heart, colon, spleen, liver, or small intestine. Immunofluorescence reveals p63 expression in skin, oral epithelium, tongue, kidney, and trachea, but not in liver, large intestine, testis, skeletal muscle, or heart. Focal p63 expression within tissues, the complex array of isoforms encoded by the gene, and the specificity of the probes and antibodies utilized, may all contribute to contradictory accounts of CUSP/p63 expression.
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PMID:CUSP/p63 expression in rat and human tissues. 1153 71

Potentiation of 5-fluorouracil/leucovorin (FUra/LV) cytotoxicity by IFN-gamma in colon carcinoma cells is dependent on FUra-induced DNA damage, the Fas death receptor, and independent of p53 and RNA-mediated FUra toxicity, which occurs in normal gastrointestinal tissues. This provides a rationale for enhancing the selective action of FUra/LV by IFN-gamma in the treatment of colorectal carcinoma. Based on results from our preclinical studies we designed a Phase I trial combining FUra (370 mg/m2) and LV (200 mg/m2), i.v. bolus daily x 5 days, with escalating doses of IFN-gamma (10-100 micro g/m2) s.c. on days 1, 3, and 5, every 28 days. Twenty-five patients with carcinomas were enrolled; 6 patients received IFN-gamma on days 1 and 3 only. The dose-limiting toxicity, stomatitis, occurred most frequently at 100 micro g/m2 IFN-gamma. Minor response or SD was observed in 2 of 9 patients and in 4 of 12 patients at dose levels of < or =50 micro g/m2 and > or =75 micro g/m2 IFN-gamma, respectively. Three evaluable chemonaive patients demonstrated partial response (2) or complete response (1). Serial plasma samples revealed peak FUra concentrations of >100 micro M; at 100 micro g/m2 IFN-gamma plasma concentrations >5 units/ml persisted for 6.5 h and >1 unit/ml for 28.5 h. The pharmacokinetic parameters of IFN-gamma correlated with a 2-3-fold up-regulation of Fas expression at 24 h in CD15+ cells in peripheral blood samples. Furthermore, clinically relevant IFN-gamma concentrations up-regulated Fas expression and sensitized HT29 colon carcinoma cells in vitro to FUra/LV cytotoxicity. On the basis of the modulation of Fas signaling, FUra/LV combined with IFN-gamma has shown activity in a Phase I trial in colorectal carcinoma and warrants additional evaluation in Phase II.
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PMID:Modulation of the Fas signaling pathway by IFN-gamma in therapy of colon cancer: phase I trial and correlative studies of IFN-gamma, 5-fluorouracil, and leucovorin. 1217 74

The small GTPase Rab2 requires atypical protein kinase C iota/lambda (PKCiota/lambda) kinase activity to promote vesicle budding from normal rat kidney cell microsomes (Tisdale, E. J. (2000) Traffic 1, 702-712). The released vesicles lack anterograde-directed cargo but contain coat protein I (COPI) and the recycling protein p53/p58, suggesting that the vesicles traffic in the retrograde pathway. In this study, we have directly characterized the role of PKCiota/lambda in the early secretory pathway. A peptide corresponding to the unique PKCiota/lambda pseudosubstrate domain was introduced into an in vitro assay that efficiently reconstitutes transport of vesicular stomatitis virus glycoprotein from the endoplasmic reticulum to the cis-medial Golgi compartments. This peptide blocked transport in a dose-dependent manner. Moreover, normal rat kidney cells incubated with Rab2 and the pseudosubstrate peptide displayed abundant swollen or dilated vesicles that contained Rab2, PKCiota/lambda, beta-COP, and p53/p58. Because Rab2, beta-COP, and p53/p58 are marker proteins for pre-Golgi intermediates (vesicular tubular clusters,VTCs), most probably the swollen vesicles are derived from VTCs. Similar results were obtained when the assays were supplemented with kinase-dead PKCiota/lambda (W274K). Both the pseudosubstrate peptide and kinase-dead PKCiota/lambda in tandem with Rab2 caused sustained membrane association of PKCiota/lambda, suggesting that reverse translocation was inhibited. Importantly, the inhibitory phenotype of kinase-dead PKCiota/lambda was reversed by PKCiota/lambda wild type. These combined results indicate that PKCiota/lambda is essential for protein transport in the early secretory pathway and suggest that PKCiota/lambda kinase activity is required to promote Rab2-mediated vesicle budding at a VTC subcompartment enriched in recycling cargo.
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PMID:Atypical protein kinase C plays a critical role in protein transport from pre-Golgi intermediates. 1287 60

Recent findings showed that type I interferons (IFN-alpha/beta) induce the transcription of tumor suppressor p53 and sensitize primary mouse embryonic fibroblasts (MEFs) to p53-mediated apoptosis by oncolytic viruses. However, the ability of RNA viruses to induce a p53-mediated apoptotic response may differ between primary and tumor cells and may be dependent upon the virus type. We have investigated this hypothesis by analyzing the apoptotic effects of various oncolytic viruses on the human colon carcinoma HCT116 cells and their derivatives lacking either p53 or bax gene. We show that HCT116 cells are resistant to the apoptotic effects of vesicular stomatitis virus, reovirus or poliovirus but activate the p53/Bax apoptotic pathway after infection with Sendai virus. These data substantiate the role of p53 in virus-mediated apoptosis and show that, unlike primary cells, tumor cells may be more selective in the activation of p53 pathway in response to the infection with specific types of viruses.
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PMID:Induction of p53-dependent apoptosis in HCT116 tumor cells by RNA viruses and possible implications in virus-mediated oncolysis. 1525 3


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