Slowacting Transforming Retroviruses

Slow-acting transforming retroviruses are as a rule replication-competent and do not transduce oncogenes. Instead, they cause transformation by integrating within or in the vicinity of cellular genes and altering their expression. In this fashion they convert cellular genes from proto-oncogenes into oncogenes in a cis-acting manner. Integration of a slow-acting retrovirus disrupts negative regulatory elements of the targeted gene and or activates its transcription by the transcriptional...

Principles Of Targeted Drug Therapy

One strategy to circumvent the problems associated with conventional chemotherapy ( 22.2) is to develop drugs against more specific targets in the cancer. This is not a fundamentally novel idea. Many drugs in current use interact with highly specific targets such as microtubular proteins or topoisomerase enzymes ( 22.2). Their targets are not specific to cancers, though. Those drugs called 'biological agents' in the previous section come closer to the ideal, since they act on specific receptor...

Cell Protection Mechanisms In Cancer

Exogenous carcinogens and potential mutagens arising from endogenous processes are often prevented from encountering DNA by specific cellular protections mechanisms. These highly diverse mechanisms serve as a further tier of cancer prevention in addition to DNA repair and apoptosis. Often, they protect not only DNA, but cells in general from damage. Some of these mechanisms are very specific and some are very general. In the context of cancer, they are particularly important during two very...

Genes And Proteins Involved In Extracellular Matrix Remodeling During Tumor Invasion

The structure of the extracellular matrix is generated by a backbone of fibrillar proteins and proteoglycans. This matrix is in a dynamic state. Structural proteins are synthesized by fibroblasts and other cells embedded in connective tissue. These same cells, together with cells of the immune system and from blood vessels, are responsible for the turnover of the extracellular material. Turnover and remodeling of the ECM are enhanced during inflammation and wound repair, as they are during...

Wolfgang Arthur Schulz

Department of Urology and Center for Biological and Medical Research, Heinrich Heine University, Dusseldorf, Germany eBook ISBN 1-4020-3186-6 Print ISBN 1-4020-3185-8 2005 Springer Science + Business Media, Inc. No part of this eBook may be reproduced or transmitted in any form or by any means, electronic, mechanical, recording, or otherwise, without written consent from the Publisher Created in the United States of America Visit Springer's eBookstore and the Springer Global Website Online at...

Invasion And Metastasis

The spread of solid cancers beyond the confinements of their tissue compartment into other parts of the same tissue and successively into neighboring tissues (invasion) and distant organs (metastasis) is the defining property of malignancy. Invasion and metastasis are decisive for the clinical course of most cancers. > Invasion and metastasis are complex processes, particularly in carcinomas, since normals epithelia are strongly adherent and are confined by a basement membrane. Before or...

Histology And Etiology Of Bladder Cancer

From the renal pelvis through the urinary bladder into the urethra, the urinary tract is lined by a specialized 'transitional' epithelium called 'urothelium' (Figure 14.1), whose structure is in several respects different from that of squamous epithelia in the skin and other organs. The urothelium forms a low permeability barrier that prevents the components of the urine, even water, from seeping back into the body. In a transitional epithelium, cells from several layers retain contact with the...