Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aberrant methylation of the CpG island promoter regions acquired by tumor cells is one mechanism for loss of gene function. The high methylation rate for RB1 and death-associated protein-kinase gene (DAP-kinase) (60 and 90%, respectively) previously found in brain metastases suggests this mechanism could be non-randomly associated to tumor progression and metastasis. Thus, in addition to these two genes, we determined the methylation status of the genes p16INK4a, glutathione S-transferase P1 (GSTP1), O6-methylguanine DNA methyltransferase (MGMT), thrombospondin-1 (THBS1), p14ARF, TP53, p73, and tissue inhibitor of metalloproteinase 3 (TIMP-3), in 18 brain metastases of solid tumors, with methylation specific PCR. The metastases were derived from malignant melanoma (three cases), lung carcinoma (six cases), breast carcinoma (three cases), ovarian carcinoma (two cases) and one each from colon, kidney, bladder and undifferentiated carcinoma. We detected methylation levels in the tumor samples of 83% in p16INK4a, 72% in DAP-kinase, 56% in THBS1, 50% in RB1, 39% in MGMT, 33% in GSTP1 and p14ARF each, 22% in p73 and TIMP-3 each, and 11% in TP53. The methylation index (number of genes methylated/number of genes tested) varied between 0.1 and 0.6, with an average of 0.42, indicating that a high grade of gene methylation accumulates parallel to the tumor metastasis process. Our data suggest an important role for gene methylation in the development of brain metastases, primarily involving epigenetic silencing of DAP-kinase, THBS1 and the cell-cycle regulators RB1/p16INK4a.
Int J Mol Med 2004 Jan
PMID:Promoter methylation status of multiple genes in brain metastases of solid tumors. 1465 77

We have investigated gene expression profiles of human ovarian carcinomas in vivo during Taxol(R) (paclitaxel) treatment and observed a difference in expression. Nude mice bearing 1A9 or 1A9PTX22 xenografts were given 60 mg/kg of paclitaxel. Therapeutic efficacy was achieved for 1A9, while 1A9PTX22 did not respond. Tumor tissues harvested 4 and 24 h after treatment were evaluated by cDNA microarray against untreated tumors. Paclitaxel caused the modulation of more genes in 1A9 than in 1A9PTX22 tumors, in accordance to their therapeutic response. Most gene expression alterations were detected 24 h after paclitaxel administration and affected genes involved in various biological functions including cell cycle regulation and cell proliferation (CDC2, CDKN1A, PLAB, and TOP2A), apoptosis (BNIP3 and PIG8), signal transduction and transcriptional regulation (ARF1, ATF2, FOS, GNA11, HDAC3, MADH2, SLUG, and SPRY4), fatty acid biosynthesis and sterol metabolism (FDPS, IDI1, LIPA, and SC5D), and IFN-mediated signaling (G1P3, IFI16, IFI27, IFITM1, and ISG15). The modulation of two representative genes, CDKN1A and TOP2A, was validated by Northern analyses on a panel of seven ovarian carcinoma xenograft models undergoing treatment with paclitaxel. We found that the changes in expression level of these genes was strictly associated with the responsiveness to paclitaxel. Our study shows the feasibility of obtaining gene expression profiles of xenografted tumor models as a result of drug exposure. This in turn might provide insights related to the drugs' action in vivo that will anticipate the response to treatment manifested by tumors and could be the basis for novel approaches to molecular pharmacodynamics.
Mol Cancer Ther 2004 Feb
PMID:Gene expression correlating with response to paclitaxel in ovarian carcinoma xenografts. 1498 51

p150(Sal2), a vertebrate homologue of the Drosophila melanogaster homeotic transcription factor Spalt, has previously been shown to be a binding target of the polyomavirus large T antigen. p150(Sal2) acts as an inhibitor of viral DNA synthesis, and the binding of p150(Sal2) by large T overcomes this inhibition. The present study focuses on the effects of p150(Sal2) on the growth and survival of ovarian carcinoma (OVCA) cells that are deficient in expression of p150(Sal2) and of normal established human ovarian surface epithelial (HOSE) cells which abundantly express the protein. Transient expression of exogenous p150(Sal2) in OVCA cells that show little or no endogenous expression resulted in inhibition of DNA synthesis and colony formation and in increased apoptosis. OVCA cells stably transfected and expressing physiological levels of p150(Sal2) showed reduced tumorigenicity accompanied by increased expression of p21(WAF1/CIP1) (p21) and BAX. Conversely, reduction of endogenous levels of p150(Sal2) in HOSE resulted in reduced p21 expression and increased DNA synthesis. p150(Sal2) bound to the p21 promoter adjacent to the known p53 binding sites and stimulated transcription in the absence of p53. We propose that p150(Sal2), acting in part as a p53-independent regulator of p21 and BAX, can function in some cell types as a regulator of cell growth and survival.
Mol Cell Biol 2004 May
PMID:p150(Sal2) is a p53-independent regulator of p21(WAF1/CIP). 1508 82

The aim of this study was to compare the prognostic value of fluorine-18 fluorodeoxyglucose positron emission tomography (FDG PET) with that of second-look laparotomy (SLL) in patients with advanced ovarian carcinoma following primary chemotherapy. Fifty-five patients who had undergone cytoreductive surgery and adjuvant chemotherapy for advanced ovarian carcinoma were enrolled in the study. Thirty patients underwent SLL after primary treatment (SLL group), while 25 underwent FDG PET after primary treatment without SLL (PET group) We retrospectively reviewed the medical records of the 55 patients for comparison of progression-free interval and disease-free interval between the two groups. Ovarian carcinomas recurred in 37 of the 55 patients. When the progression-free interval and the disease-free interval in patients in the PET group were compared with those in the SLL group, no significant differences were observed. The progression-free interval in the PET and SLL groups were 28.8 +/- 12.7 months and 30.6 +/- 13.7 months, respectively (P = 0.29). The disease-free interval in the negative PET group was 40.5 +/- 11.6 months, and that in the negative SLL group was 48.6 +/- 12.1 months (P = 0.12). In conclusion, FDG PET has a similar prognostic value to SLL, and can substitute for SLL in the follow-up of patients who have had ovarian carcinoma, especially when there is a high risk for recurrence.
Eur J Nucl Med Mol Imaging 2004 Feb
PMID:[18F]FDG PET as a substitute for second-look laparotomy in patients with advanced ovarian carcinoma. 1512 1

Cells selected for resistance to cisplatin are often cross-resistant to copper and vice versa, and the major copper influx transporter copper transport protein 1 (CTR1) has been shown to regulate the uptake of cisplatin, carboplatin, and oxaliplatin in yeast. To further define the role of hCTR1 in human tumor cells, the ovarian carcinoma cell line A2780 was molecularly engineered to increase expression of hCTR1 by a factor of 20-fold. Enhanced expression of hCTR1 in the A2780/hCTR1 cells was associated with a 6.5-fold increase in basal steady-state copper content and a 13.7-fold increase in initial copper influx, demonstrating that the exogenously expressed hCTR1 was functional in altering copper homeostasis. The A2780/hCTR1 cells accumulated 46% more platinum after a 1-h exposure to 2 microM cisplatin, and 55% more after a 24 h exposure, than the control A2780/empty vector cells. The initial uptake of cisplatin was 81% higher in the A2780/hCTR1 cells when measured at 5 min. Thus, increased expression of hCTR1 had a substantially larger effect on the cellular pharmacology of copper than cisplatin. Interestingly, the increased uptake of copper and cisplatin was accompanied by only a marginal increase in sensitivity to the cytotoxic effect of copper and cisplatin, and there was no increase in the extent of cisplatin-DNA adduct formation. Thus, although increased expression of hCTR1 mediates greater cellular accumulation of copper and cisplatin, hCTR1 delivers these compounds into intracellular compartments from which they do not have ready access to their key cytotoxic targets.
Mol Pharmacol 2004 Oct
PMID:The copper influx transporter human copper transport protein 1 regulates the uptake of cisplatin in human ovarian carcinoma cells. 1522 96

Cisplatin is a DNA damaging agent widely used as a chemotherapeutic agent. A major limitation of the use of this agent is the development of drug resistance within tumors. Several in vitro models exist which enable the investigation of resistance mechanisms, including 2008/C13* ovarian carcinoma cells. C13* cells are variants of 2008 cells, displaying cisplatin resistance following 13 consecutive cisplatin treatments. This model system has led to the identification of several mechanisms that play parts in the multifactorial nature of cisplatin resistance. In this study, we have examined the contribution of a transcription factor, Ets-1, to the cisplatin resistance of C13* cells. Ets-1 is up-regulated in C13* cells as compared with the cisplatin-sensitive 2008 cells and overexpression of this protein in 2008 cells led to a 7-fold increase in resistance. Further studies on a colorectal carcinoma cell line overexpressing Ets-1 indicated that this phenomenon is not cell specific-increased cisplatin resistance correlated to Ets-1 expression. The mechanism of cisplatin resistance elicited by Ets-1 is potentially via transcriptional activation of genes whose products have well-described functions in reducing cisplatin toxicity. Examples, identified via microarray analysis, include metallothioneins and DNA repair enzymes. This is the first report to our knowledge associating expression of Ets-1, a transcription factor whose expression often signals poor prognosis in various cancer types, to cisplatin resistance.
Mol Cancer Ther 2004 Jul
PMID:Role of the transcription factor Ets-1 in cisplatin resistance. 1525 43

Platinum agents and paclitaxel (taxol) are among the most effective drugs currently available for treatment of ovarian cancer. One of the hurdles with taxol and platinum- based therapy is the clinical development of resistance to these agents. To investigate the mechanism of drug resistance in human ovarian cancer, we developed and characterized 5 cell models for chemoresistance studies of cisplatin, carboplatin and taxol. We report in this study that these human ovarian carcinoma cell model systems include 2 models for cisplatin resistance, 2 models for carboplatin resistance, and 1 model for taxol resistance. The biological and biochemical characteristics of the models showed that (i), the IC50 values of the drugs for all these resistant cell models were 3 times (or more) higher than those for the parental tumor cells. There also exist varying degrees of cross-resistance to several other chemotherapeutic agents in these systems. Moreover, the intracellular drug accumulations in these cells were significantly reduced as compared to those in the parental cells. (ii), The proliferation rates of these resistant cells were markedly decreased. However, there were no obvious changes in cell cycle distribution in these model systems. (iii), Our results for the expression of a few major drug resistance-related genes revealed that the expression of p53, lrp-1 and mrp-1 was decreased, while the expression of pkc, topo I and topo II beta was increased in the resistant tumor cells as compared with the parental cells. In contrast, no significant alterations in gst-pi and topo II alpha expression were found. Interestingly, the levels of mdr-1 expression were elevated in some models, but were reduced in others, thus suggesting that different pathways are involved in the formation of drug resistance in different cell model systems, and that different mechanisms are responsible for the development of different drug resistances in tumor cells. Taken together, our findings indicate that these models may be potentially used to assess the biochemical and genetic mechanisms of drug resistance in human ovarian cancer and to identify new drug resistance-related genes.
Int J Mol Med 2004 Aug
PMID:Development and characterization of five cell models for chemoresistance studies of human ovarian carcinoma. 1525 75

CD24 is a molecule that recently has raised considerable attention in tumour biology. It is involved in cell adhesion and metastatic tumour spread. It has also been described as a new diagnostic marker of tumours, of neuroendocrine differentiation and, possibly most intriguing of all, of patient prognosis. High rates of CD24 expression detected by immunohistochemistry have been found in epithelial ovarian cancer (83%), breast cancer (85%), non-small cell lung cancer (45%), prostate cancer (48%) and pancreatic cancer (72%). With the exception of pancreatic cancer, high rates of CD24 are significantly associated with a more aggressive course of the disease, a finding that remains significant in a multivariate analysis. The aim of this review is to summarize relevant work covering these aspects of CD24.
J Mol Histol 2004 Mar
PMID:Tumour biological aspects of CD24, a mucin-like adhesion molecule. 1533 45

Karyotype and fluorescence in situ hybridization (FISH) analyses previously identified a homogeneously staining region (HSR) derived from chromosome 22 in OV90, an epithelial ovarian cancer (EOC) cell line. Affymetrix expression microarrays in combination with the UniGene and Human Genome Browser databases were used to identify the candidate genes comprising the amplicon of the HSR, based on comparison of expression profiles of OV90, EOC cell lines lacking HSRs and primary cultures of normal ovarian surface epithelial (NOSE) cells. A group of probe sets displaying a minimum 3-fold overexpression with a high reliability score (P-call) in OV90 were identified which represented genes that mapped within a 1-2 Mb interval on chromosome 22. A large number of probe sets, some of which represent the same genes, displayed no evidence of overexpression and/or low reliability scores (A-call). An investigation of the probe set sequences with the Affymetrix and Sanger Institute Chromosome 22 Group databases revealed that some of the probe sets displaying discordant results for the same gene were complementary to intronic sequences and/or the antisense strand. Microarray results were validated by RT-PCR. Genomic analysis suggests that the HSR was derived from the amplification of a 1.1 Mb interval defined by the chromosomal map positions of ZNF74 and Hs.372662, at 22q11.21. The deduced amplicon is derived from a complex region of chromosome 22 that harbors low-copy repeats (LCRs). The amplicon contains 18 genes as likely targets for gene amplification. This study illustrates that large-scale expression microarray analysis in combination with genome databases is sufficient for deducing target genes associated with amplicons and stresses the importance of investigating probe set design before engaging in validation studies.
Mol Carcinog 2004 Sep
PMID:Gene expression microarray analysis and genome databases facilitate the characterization of a chromosome 22 derived homogeneously staining region. 1535 23

Malignant transformation of the ovarian surface epithelium (OSE) accounts for most ovarian carcinoma. Detection of preneoplastic changes in the OSE leading to overt malignancy is important in prevention and management of ovarian cancer. We identified OSE proteins with altered expression derived from women with a family history (FH) of ovarian and/or breast cancer and mutations in the BRCA1 tumor suppressor gene. Proteins from SV-40-transformed FH-OSE cell lines and control OSE lines derived from women without such histories (non-family history) were separated by two-dimensional PAGE. Gels were analyzed, a protein data base was created, and proteins were characterized according to their molecular weight, isoelectric point, and relative abundance. Mass spectrometry was performed on tryptic protein digests, and data bases were searched for known proteins with the same theoretical tryptic peptide masses. Several proteins showed altered expression in the FH-OSE cells. Beta-tubulin and to a lesser extent ubiquitin carboxyl-terminal hydrolase and glyoxalase 1 appeared to be up-regulated. In contrast, proteins suppressed in FH lines include the 27-kDa heat shock protein, translationally controlled tumor protein, and several proteins associated with actin modification such as actin prepeptide, F-actin capping protein alpha subunit, and cofilin. Sequencing of several cofilin gel spots revealed phosphorylation of serine 3, a post-translational modification associated with decreased actin binding and cytoskeletal reorganization. Two-dimensional Western blots probed with cofilin antibody showed multiple protein spots with isoelectric points of 6-9 pH units. Blots of one-dimensional gels showed a significant reduction in cofilin expression in three FH lines when compared with three non-family history lines (p < or = 0.05). Identification of these and other OSE proteins may be useful in detecting changes suggestive of increased risk of developing preneoplastic disease and defining the possible role(s) of the BRCA1 gene in regulation of OSE cell function.
Mol Cell Proteomics 2005 Feb
PMID:Proteome changes in ovarian epithelial cells derived from women with BRCA1 mutations and family histories of cancer. 1559 24


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