Autotaxin (ATX) is an exoenzyme that potently induces tumor cell motility, and enhances experimental metastasis and angiogenesis. ATX was shown recently to be identical to serum lysophospholipase D activity, producing lysophosphatidic acid (LPA) from lyso-glycerophospholipids. LPA, itself a strong chemoattractant for tumor cells, may mediate the actions of ATX.
View Article and Find Full Text PDFColon and ovarian cancers can be difficult to distinguish in the abdomen, and the distinction is important because it determines which drugs will be used for therapy. To identify molecular markers for that differential diagnosis, we developed a multistep protocol starting with the 60 human cancer cell lines used by the National Cancer Institute to screen for new anticancer agents. The steps included: (a) identification of candidate markers using cDNA microarrays; (b) verification of clone identities by resequencing; (c) corroboration of transcript levels using Affymetrix oligonucleotide chips; (d) quantitation of protein expression by "reverse-phase" protein microarray; and (e) prospective validation of candidate markers on clinical tumor sections in tissue microarrays.
View Article and Find Full Text PDFLaser capture microdissection was combined with reverse phase protein lysate arrays to quantitatively analyze the ratios of mitochondrial encoded cytochrome c oxidase subunits to nuclear encoded cytochrome c oxidase subunits, and to correlate the ratios with malignant progression in human prostate tissue specimens. Cytochrome c oxidase subunits I-III comprise the catalytic core of the enzyme and are all synthesized from mitochondrial DNA. The remaining subunits (IV-VIII) are synthesized from cellular nuclear DNA.
View Article and Find Full Text PDFThe field of proteomics holds promise for the discovery of new biomarkers for the early detection and diagnosis of disease, molecular targets for therapy and markers for therapeutic efficacy and toxicity. A variety of proteomics approaches may be used to address these goals. Two-dimensional gel electrophoresis (2D-PAGE) is the cornerstone of many discovery-based proteomics studies.
View Article and Find Full Text PDFJ Mammary Gland Biol Neoplasia
October 2002
Clinical proteomics is an exciting new subdiscipline of proteomics that involves bedside application of proteomic technologies. A new and potentially revolutionary technology and approach for early disease detection, surveillance, and monitoring is proteomic pattern diagnostics. Using this approach, high throughput mass spectrometry generates a proteomic fingerprint of a given body fluid, such as serum or nipple fluid aspirants (NAF), in less than 30 s.
View Article and Find Full Text PDFThe advent of proteomics has brought with it the hope of discovering novel biomarkers that can be used to diagnose diseases, predict susceptibility and monitor progression. Much of this effort has focused upon the mass spectral identification of the thousands of proteins that populate complex biosystems such as serum and tissues. A revolutionary approach in proteomic pattern analysis has emerged as an effective method for the early diagnosis of diseases such as ovarian cancer.
View Article and Find Full Text PDFVessel wall extracellular matrix, which underlies the endothelium, is a potent stimulator of platelet adhesion and activation. Exposure of this matrix can result from damage incurred by vascular interventions, such as saphenous vein bypass grafting and angioplasty. Fibrillar collagens are an important component of the thrombogenic extracellular matrix.
View Article and Find Full Text PDFProteomics, the systematic evaluation of changes in the protein constituency of a cell, is more than just the generation of lists of proteins that increase or decrease in expression as a cause or consequence of disease. The ultimate goal is to characterize the information flow through protein pathways that interconnect the extracellular microenvironment with the control of gene transcription. The nature of this information can be a cause or a consequence of disease processes.
View Article and Find Full Text PDFThe exo-enzyme autotaxin/NPP2 (ATX/NPP2) is a potent stimulator of cell migration, invasion, metastasis, and angiogenesis. Recently, ATX/NPP2 was found to possess lysophospholipase D (lyso-LPD) activity, generating the bioactive mediator lysophosphatidic acid from precursors. In the present study, we used site-directed mutagenesis to delineate the active domain of lysophospholipid catalytic activity and to examine potential overlap with the nucleotide phosphodiesterase domain.
View Article and Find Full Text PDFProtein microarrays, one emerging class of proteomic technologies, have broad applications for discovery and quantitative analysis. A rapidly expanding use of this technology is the acquisition of information about the posttranslational modifications of proteins reflecting the activity state of signal pathways and networks, and is now employed for the analysis of biopsy samples in clinical trial research.
View Article and Find Full Text PDFThe ability of physicians to effectively treat and cure cancer is directly dependent on their ability to detect cancers at their earliest stages. Proteomic analyses of early-stage cancers have provided new insights into the changes that occur in the early phases of tumorigenesis and represent a new resource of candidate biomarkers for early-stage disease. Studies that profile proteomic patterns in body fluids also present new opportunities for the development of novel, highly sensitive diagnostic tools for the early detection of cancer.
View Article and Find Full Text PDFTechnol Cancer Res Treat
August 2002
As we emerge into the post-genome era, proteomics finds itself as the driving force field as we translate the nucleic acid information archive into understanding how the cell actually works and how disease processes operate. Even so, the traditionally held view of proteomics as simply cataloging and developing lists of the cellular protein repertoire of a cell are now changing, especially in the sub-discipline of clinical proteomics. The most relevant information archive to clinical applications and drug development involves the elucidation of the information flow of the cell; the "software" of protein pathway networks and circuitry.
View Article and Find Full Text PDFJ Synchrotron Radiat
March 2003
Time-resolved X-ray diffraction experiments carried out at the beamline BM08-GILDA of ESRF allowed a study of the structural modifications taking place in a Pt/ceria-zirconia catalyst while the CO oxidation reaction was in progress. The capillary tube in which the sample is stored acts effectively as a chemical microreactor that ensures homogeneity of the sample treatments and minimization of diffusion effects. During the flowing of the reactant CO/He mixture, the investigated catalyst undergoes a fast Ce(IV)-Ce(III) partial reduction that involves the release of one O atom for every two reduced Ce cations.
View Article and Find Full Text PDFProteomic technologies promise to accelerate rapidly a new era in molecular medicine, especially in the detection and discovery of disease-related biomarkers. These technologies have no bigger impact than in the field of human cancer research. Beyond lifestyle-associated prevention strategies, early detection of cancer has the most profound impact on the ultimate course of the disease: the earlier the cancer is detected, the better the prognosis.
View Article and Find Full Text PDFNow that the human genome has been mapped, a new challenge has emerged: deciphering the various products of individual genes. Consequently, new proteomic technologies are being developed to monitor and identify protein function and interactions responsible for the total activities of the cell. The application of these new proteomic technologies to study cellular activities, will lead to a faster sample throughput and increased sensitivity for the detection of individual proteins, thus providing major opportunities for the discovery of new biomarkers for the early detection of protein alterations associated with the progression of the disease state.
View Article and Find Full Text PDFPurpose: The role of growth factors in ovarian cancer development and progression is complex and multifactorial. We hypothesized that new growth factors may be identified through the molecular analysis of ovarian tumors as they exist in their native environment.
Experimental Design: RNA extracted from microdissected serous low malignant potential (LMP) and invasive ovarian tumors was used to construct cDNA libraries.
Proteomic studies of cells via surface-enhanced laser desorption/ionization spectrometry (SELDI) analysis have enabled rapid, reproducible protein profiling directly from crude samples. We applied this technique to archival cytology material to determine whether distinct, reproducible protein fingerprints could be identifiedfor potential diagnostic purposes in blinded specimens. Rapid Romanowsky-stained cytocentrifuged specimens from fine-needle aspirates of metastatic malignant melanoma (with both known cutaneous primary and unknown primary sites), clear cell sarcoma, and renal cell carcinoma and reactive effusions were examined using the SELDI technology.
View Article and Find Full Text PDFDNA microarrays are powerful tools for high throughput analysis of gene expression; however, they do not measure protein expression. Current methods for producing protein arrays require sophisticated equipment or extensive protein modification. We developed a low overhead, customizable assay platform called frozen protein arrays that can detect native proteins in protein lysates.
View Article and Find Full Text PDFAdvances in molecular biology over the past decade have helped to enhance our understanding of the complex interplay between genetic, transcriptional and translational alterations in human cancers. These molecular changes are the basis for an evolving field of high-throughput cancer discovery techniques using microscopic amounts of patient-based materials. Laser capture microdissection allows pure populations of cells to be isolated from both the tumor and stroma in order to identify subtle differences in RNA and protein expression.
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