Purpose: Fas-Fas ligand (FasL)-mediated death pathway is important in the life and death of immune cells and, therefore, influences immune surveillance of carcinogenesis. This study examined the association between functional variants of Fas (-1377G-->A and -670A-->G), FasL (-844T-->C), and caspase-8 (CASP8) six-nucleotide deletion polymorphism (-652 6N ins-->del) and risk of pancreatic cancer.
Experimental Design: Genotypes were determined in 397 cases with pancreatic cancer and 907 controls.
Purpose: The excision repair cross-complementation group 1 (ERCC1) plays a pivotal role in DNA repair and has been linked to protection against carcinogenesis and resistance to platinum-based anticancer drugs. We tested whether genetic variants in the ERCC1 gene are associated with susceptibility to lung cancer and efficacy of platinum-chemotherapy in patients with small cell lung cancer (SCLC).
Experimental Design: Thirty individual DNA samples were sequenced to search for single-nucleotide polymorphisms, and the functions of the variants were investigated by a series of biochemical assays.
Curr Protoc Protein Sci
February 2004
This unit discusses the issues that must be considered in the design, production, and characterization of polyclonal and monoclonal sequence-specific anti-phosphoamino acid antibodies. Protocols are provided for generating and purifying such antibodies, and methods are also provided for producing useful polyclonal antibodies in a non-purified form. Support protocols describe coupling of peptides or phosphotyrosine to a solid support for use in affinity chromatography.
View Article and Find Full Text PDFWe previously demonstrated that liposome-incorporated antisense oligodeoxynucleotide specific for the grb2 mRNA (L-Grb2) inhibited Grb2 protein expression and the proliferation of bcr-abl-positive leukemia cell lines. To determine whether L-Grb2 has the potential of being a therapeutic modality against bcr-abl-positive leukemia, we studied the tissue distribution of L-Grb2 in normal mice before studying its effects in mice bearing bcr-abl-positive leukemia xenografts. L-Grb2 was widely distributed in the body.
View Article and Find Full Text PDFThe P53 tumor suppressor pathway plays an important role in cancer development. The auto-regulatory feedback mechanism of the P53 and MDM2 expression is critical in keeping proper tumor suppressor function of this pathway. This study examined the effect of P53 Arg72Pro variants on transactivation of polymorphic MDM2 promoter (T309G) and their associations with risk of developing gastric cardia adenocarcinoma (GCA) in a Chinese population.
View Article and Find Full Text PDFAn oncogenic D842V mutation in the platelet-derived growth factor (PDGF) alpha-receptor (Pdgfra) has recently been described in patients with gastrointestinal stromal tumors. In order to test if the same mutation would confer oncogenic properties to the homologous PDGF beta-receptor (Pdgfrb), the corresponding aspartic acid residue at position 849 of Pdgfrb was changed into valine (D849V) using a knock-in strategy. This mutation turned out to be dominantly lethal and caused death even in chimeras (from 345 transferred chimeric blastocysts, no living coat chimeras were detected).
View Article and Find Full Text PDFBackground: Aberrant arachidonic acid metabolism by 12-lipoxygenase (12-LOX) and cyclooxygenase-2 (COX-2) has been implicated in human carcinogenesis. Inherited polymorphisms in 12-LOX and COX-2 contributed to differential expression or activity of these enzymes might confer interindividual susceptibility to cancer.
Objective: To examine the functional significance of 12-LOX 261 Arg> Gln polymorphism and its association, alone and in combination with COX-2 -1195G > A and -765G > C polymorphisms, with risk of developing esophageal squamous cell carcinoma (ESCC).
Caspases are important in the life and death of immune cells and therefore influence immune surveillance of malignancies. We tested whether genetic variants in CASP8, CASP10 and CFLAR, three genes important for death receptor-induced cell killing residing in tandem order on chromosome 2q33, are associated with cancer susceptibility. Using a haplotype-tagging SNP approach, we identified a six-nucleotide deletion (-652 6N del) variant in the CASP8 promoter associated with decreased risk of lung cancer.
View Article and Find Full Text PDFPurpose: Genetic variation in CD14 may affect CD14 expression and susceptibility to Helicobacter pylori infection-related cancers. This study examined functional single nucleotide polymorphisms (SNP) in the CD14 promoter and their associations with risk of developing gastric carcinoma in relation to H. pylori infection.
View Article and Find Full Text PDFA novel Er-doped silica fiber, with heavy Er doping, was specially developed for application to a single frequency fiber laser. Two high temperature-sustainable fiber Bragg gratings, written into Bi-Ge codoped photosensitive fiber, were chosen for the application and spliced to the specialist Er doped silica fiber to form a compact, linear cavity, fiber laser. The fiber laser retained single mode oscillation over a wide temperature range, from room temperature to 400 degrees C.
View Article and Find Full Text PDFThe FAS-FASL system plays crucial role in counterattack of cancer cell against immune system. This study examined the effects of FAS (-1377G/A and -670A/G) and FASL (-844T/C and 7896G/C) polymorphisms on breast cancer risk and apoptosis of T lymphocytes. The effect on breast cancer risk was determined by case-control analysis of 840 patients and 840 controls.
View Article and Find Full Text PDFCarboxypeptidase E (CPE) has important functions in processing of endocrine pro-peptides, such as pro-insulin, pro-opiomelanocortin, or pro-gonadotropin-releasing hormone, as evidenced by the hyper-pro-insulinemia, obesity, and sterility of Cpe mutant mice. Down-regulation of Cpe in enlarged placentas of interspecific hybrid (interspecies hybrid placental dysplasia (IHPD)) and cloned mice suggested that reduced CPE enzyme and receptor activity could underlie abnormal placental phenotypes. In this study, we have explored the role of Cpe in murine placentation by determining its expression at various stages of gestation, and by phenotypic analysis of Cpe mutant placentas.
View Article and Find Full Text PDFAberrant arachidonic acid metabolism by cyclooxygenase (COX)-2 and 12-lipoxygenase (LOX) has implicated in carcinogenesis. Genetic polymorphisms in COX-2 and 12-LOX might therefore affect susceptibility to colorectal cancer (CRC). To examine this hypothesis, genotypes of COX-2 -1290A>G, -1195G>A, -765G>C and 12-LOX 261Arg>Gln polymorphisms were determined in 1000 CRC patients and 1300 controls.
View Article and Find Full Text PDFPurpose: Matrix metalloproteinases (MMP) play important roles in cancer development and single nucleotide polymorphisms (SNP) in some MMP genes were shown to confer susceptibility to certain cancers. This study examined the association between genotypes and haplotypes in the MMP1-MMP3-MMP12 gene cluster and risk of lung cancer development and metastasis.
Experimental Design: A two-stage investigation was conducted.
The Bcr-Abl tyrosine kinase is the causative factor in most chronic myelogenous leukemia (CML) patients. We have shown that Bcr-Abl is associated with a cluster of signaling proteins, including Janus kinase (Jak) 2, growth factor receptor binding protein 2-associated binder (Gab) 2, Akt, and glycogen synthase kinase (GSK)-3beta. Treatment of CML cell lines and mouse Bcr-Abl+ 32D cells with either Jak2 short interfering RNA or Jak2 kinase inhibitor AG490 inhibited pTyr Gab2 and pSer Akt formation, inhibited the activation of nuclear factor-kappaB, and caused the activation of GSK-3beta, leading to the reduction of c-Myc.
View Article and Find Full Text PDFZhonghua Zhong Liu Za Zhi
January 2006
Objective: This case-control study was designed to detect the association between STK15 Phe31Ile polymorphism and colorectal cancer.
Methods: Genotypes were determined in 283 patients with colorectal cancer and 283 controls. The adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression model.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao
April 2006
Objective: To examine the genetic polymorphisms in the promoter region of cyclooxygenase-2 ( COX-2) and evaluate their association with the risk of gastric cancer.
Methods: Single-strand conformational polymorphism and DNA sequencing were used to screen the genetic variants of the COX-2 promoter region. Total 323 patients with gastric cancer and 646 frequency-matched controls were genotyped by polymerase chain reaction-restriction fragment length polymorphism method.
Prostaglandin (PGE) 2 is the most common prostanoid and plays an important role in female reproduction. The aim of this study was to examine the expression and regulation of microsomal (m) PGE synthase (PGES)-1 and cytosolic (c) PGES in the mouse ovary during sexual maturation, gonadotropin treatment and luteal development by in situ hybridization and immunohistochemistry. Both mPGES-1 mRNA signals and immunostaining were localized in the granulosa cells, but not in the thecal cells and oocytes.
View Article and Find Full Text PDFZhongguo Yi Xue Ke Xue Yuan Xue Bao
December 2005
Objective: To investigate the association between methylentetrahydrofolate reductase (MTHFR) polymorphisms and risk of lung cancer.
Methods: Totally 505 cases with lung cancer and 500 frequency-matched controls were genotyped for the MTHFR C677T and A1298C polymorphisms by polymerase chain reaction-restriction fragment length polymorphism methods. The odds ratios (OR) and 95% confidence intervals (CI) were calculated using unconditional logistic regression model.
Zhonghua Yi Xue Za Zhi
August 2005
Objective: The FAS and FASL system plays a key role in regulating apoptotic cell death and corruption of this signaling pathway has been shown to participate in tumorigenesis. We previously have shown that the FAS-1377G/A and FASL-844T/C polymorphisms are associated with esophageal cancer. This case-control study was to examine the contribution of the polymorphisms to susceptibility of colorectal cancer.
View Article and Find Full Text PDFThe tumor suppressor TP53 pathway plays a crucial role in preventing carcinogenesis through its ability to impose cell cycle arrest and apoptosis following DNA damage and oncogene activation. MDM2 is a key negative regulator of the TP53 pathway and is overexpressed in many cancers as oncoprotein. We investigated the association between genetic variation in the promoter region of MDM2 (c.
View Article and Find Full Text PDFDifferent causes, such as maternal diabetes, cloning by nuclear transfer, interspecific hybridization, and deletion of some genes such as Esx1, Ipl, or Cdkn1c, may underlie placental overgrowth. In a previous study, we carried out comparative gene expression analysis in three models of placental hyperplasias, cloning, interspecies hybridization (IHPD), and Esx1 deletion. This study identified a large number of genes that exhibited differential expression between normal and enlarged placentas; however, it remained unclear how altered expression of any specific gene was related to any specific placental phenotype.
View Article and Find Full Text PDFThe FAS receptor-ligand system plays a key role in regulating apoptotic cell death, and corruption of this signaling pathway has been shown to participate in tumor-immune escape and carcinogenesis. We have recently demonstrated (Sun, T., X.
View Article and Find Full Text PDFBackground & Objective: UDP-glucuronosyltransferase 1A7 (UGT1A7) plays an important role in detoxification through catalyzing combination of glucuronic acid and tobacco carcinogens, including benzo [alpha] pyrene, nitrosamine, and heterocyclic amine PhIP, therefore, inactivates the carcinogens. This study was to examine the correlation of polymorphisms of UGT1A7 gene to genetic susceptibility of lung cancer.
Methods: Polymorphisms of UGT1A7 gene at 12-131 and 208 sites in peripheral lymph cells of 312 patients and 317 age- and sex-matched controls were detected by polymerase chain reaction-denaturized high performance liquid chromatography (PCR-DHPLC) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP); the correlation of these polymorphisms to genetic susceptibility of lung cancer was analyzed.
Background: Previous studies have shown that patients with Bcr-Abl-positive acute lymphoblastic leukemia (ALL) either have primary disease that is refractory to imatinib mesylate or develop disease recurrence after an initial response.
Methods: The authors investigated the effects of a newly designed Bcr-Abl inhibitor, AMN107, by comparing its in vitro inhibitory potency on p190 Bcr-Abl ALL cell lines with that of imatinib.
Results: In two Philadelphia (Ph)-positive ALL cell lines, AMN107 was found to be 30-40 times more potent than imatinib in inhibiting cellular proliferation.