Tumor Stem Cells (tumor + stem_cell)

Distribution by Scientific Domains


Selected Abstracts


Liver stem cells and hepatocellular carcinoma,

HEPATOLOGY, Issue 1 2009
Lopa Mishra
Although the existence of cancer stem cells (CSCs) was first proposed over 40 years ago, only in the past decade have these cells been identified in hematological malignancies, and more recently in solid tumors that include liver, breast, prostate, brain, and colon. Constant proliferation of stem cells is a vital component in liver tissues. In these renewing tissues, mutations will most likely result in expansion of the altered stem cells, perpetuating and increasing the chances of additional mutations and tumor progression. However, many details about hepatocellular cancer stem cells that are important for early detection remain poorly understood, including the precise cell(s) of origin, molecular genetics, and the mechanisms responsible for the highly aggressive clinical picture of hepatocellular carcinoma (HCC). Exploration of the difference between CSCs from normal stem cells is crucial not only for the understanding of tumor biology but also for the development of specific therapies that effectively target these cells in patients. These ideas have drawn attention to control of stem cell proliferation by the transforming growth factor beta (TGF-,), Notch, Wnt, and Hedgehog pathways. Recent evidence also suggests a key role for the TGF-, signaling pathway in both hepatocellular cancer suppression and endoderm formation, suggesting a dual role for this pathway in tumor suppression as well as progression of differentiation from a stem or progenitor stage. This review provides a rationale for detecting and analyzing tumor stem cells as one of the most effective ways to treat cancers such as HCC. (HEPATOLOGY 2009;49:318,329.) [source]


Melanoma stem cells: targets for successful therapy?

JOURNAL DER DEUTSCHEN DERMATOLOGISCHEN GESELLSCHAFT, Issue 7 2008
Roland Houben
Summary Increasing evidence suggests that cancer is a disease in which the persistence of the tumor relies on a small population of tumor-initiating cells, the so called tumor stem cells (TSC). Only these cells are capable of self-renewal and thereby possess the ability for unlimited proliferation. One reason for the inability of conventional tumor treatments to achieve long-term cures seems to be that TSC are resistant to many therapeutic approaches. A detailed characterization of TSC should have a substantial impact on the optimization of therapeutic protocols. While TSC in hematopoietic malignancies have been most intensively studied, subpopulations with stem cell properties have been identified in some solid tumors including breast carcinomas, gliomas and melanomas. In case of melanoma, however, a clear-cut molecular characterization is still pending. Considerable research is needed to establish standard procedures for the isolation of melanoma stem cells to facilitate determining how these cells, critical for tumor persistence and progression, can be effectively eliminated. A pressing question is if melanoma stem cells are in principle sensitive to immunotherapy. [source]


Neoplastic stem cells: A novel therapeutic target in clinical oncology

CANCER, Issue 10 2006
Axel Schulenburg MD
Abstract Cancer is among the leading causes of morbidity and mortality in the Western world. Despite recent advances, most therapeutic approaches fail to eradicate the entire neoplastic clone. The remaining cells often develop metastasis and/or recurrences and therefore may represent attractive targets of therapy. A new exciting concept in this regard suggests that each neoplasm represents a heterogeneous population of cells that pertain to long-term tumor growth both in vivo in the natural host and in experimental animals. This concept postulates the existence of small fractions of ,tumor stem cells' that exhibit a capacity for self-renewal and unlimited growth and therefore are distinct from their progeny. Based on these hypotheses, the targeting of neoplastic stem cells is considered indispensable for eradication of the entire clone and for the development of curative treatment approaches. However, tumor stem cells often may be quiescent cells and may express a different profile of targets compared with ,more mature' tumor cells. Therefore, current efforts have attempted to characterize target expression profiles in cancer stem cells in various malignancies. In the this review, the authors have provided a brief summary of the current knowledge of neoplastic stem cells and the application of respective concepts in translational oncology with the ultimate objective of improving anticancer therapy. Cancer 2006. © 2006 American Cancer Society. [source]