Biomedical subjects
Publications and source records attributed to Joseph L Lasky.
Parameningeal rhabdomyosarcoma in children has a lower survival than rhabdomyosarcoma at other more favorable sites. This report describes the case of a 14-year-old girl who was successfully treated with multimodal therapy including chemotherapy, radiation, and endoscopic surgery.
Stem cells are commonly defined as undifferentiated cells capable of self-renewing and giving rise to a large number of differentiated progeny. It is becoming increasingly apparent that there exist cancer stem cells (CSCs) from which the cells of any given malignancy arise, whereby only a few cells out of a population of cancer cells are able to initiate tumor formation. These CSCs, like their normal counterparts, are characterized by self-renewal and the ability to "differentiate" into all of the cell types in the original tumor. Current chemotherapeutic strategies involve using non-specific cytotoxic agents that target rapidly cycling cells. Although this may reduce disease burden in many cases, these therapies may miss the rare, self-renewing population that truly gives rise to the malignancy (the CSC). This review will focus on the recent discovery of stem cell-like cells in human brain tumors, putative "brain cancer stem cells," which exhibit the properties of self-renewal and the ability to recapitulate the original tumor heterogeneity. Dissecting the molecular mechanisms that underlie the ability of these cells to self-renew and maintain quiescence may allow the development of novel therapeutic strategies that will allow for more efficacious and less toxic therapies for these devastating malignancies.
Cancer stem cells (CSC) are recently proposed to be the cancer initiating cells responsible for tumorigenesis and contribute to cancer resistance. Advances have been made in identifying and enriching CSC in leukemia and several solid tumors, including breast, brain and lung cancers. These studies suggest that, like normal stem cells, CSCs should be rare, quiescent, and capable of self-renewing and maintaining tumor growth and heterogeneity. Although the concept of CSC originates from that of normal stem cells, CSCs are not necessarily aberrant counterparts of normal stem cells. In fact, they may arise from stem cells or committed progenitors of corresponding tissues, and even cells from other tissues. At the molecular level, the alteration of stem cell self-renewal pathway(s) has been recognized as an essential step for CSC transformation. Better understanding of CSC will no doubt lead to a new era of both basic and clinical cancer research, re-classification of human tumors and development of novel therapeutic strategies specifically targeting CSC.
The Notch signaling pathway is central to a wide array of developmental processes in a number of organ systems, including hematopoiesis, somitogenesis, vasculogenesis, and neurogenesis. These processes involve maintenance of stem cell self-renewal, proliferation, specification of cell fate or differentiation, and apoptosis. Recent studies have led to the recognition of the role of the Notch pathway in early neurodevelopment, learning, and memory, as well as late-life neurodegeneration. This review summarizes what is currently known about the role of the Notch pathway in neural stem cells, gliogenesis, learning and memory, and neurologic disease.