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Ovarian Stem Cell Biology and the Emergence of Ovarian Cancer Stem Cells ANJALI KUSUMBE and SHARMILA BAPAT
6.1 INTRODUCTION Ovarian cancer is widely recognized as an asymptomatic disease and progresses rapidly, delaying the diagnosis to an advanced stage when prognosis is extremely poor.[1;2] Survival rates at the early stage of ovarian carcinoma range from 70 to 90%, compared with 20 to 25% at the advanced stage of the disease.[3] Recently, cancer has been viewed as being propagated by a minority of cells that display stem cell–like characteristics and are termed cancer stem cells (CSCs). Unfortunately, research in this facet of ovarian cancer is at present limited, due to the paucity of understanding of the stem cell population residing within normal ovarian tissue. Unlike the hematopoietic system or organs such as breast and brain, where normal stem cell populations have been identified and their commitment and differentiation along various lineages dissected out precisely, ovarian stem cell lineages and markers for their identification remain unrevealed.
6.2 OVERVIEW OF THE HUMAN OVARY 6.2.1 Histological Landmarks The surface of the adult ovary is covered by a layer of epithelium termed ovarian surface epithelium (OSE) and is continuous with the mesothelium of the ovarian ligament (mesovarium) and peritoneum. The OSE proliferates under the influence of pituitary gonadotrophins, ovarian steroids, and other growth factors to repair the postovulation trauma. Beneath the OSE lies the dense connective tissue capsule termed the ovarian cortical interstitium or tunica albuginea. As in many other organs, ovarian tissue is also organized into an outer cortex and an inner medulla. Cancer Stem Cells: Identification and Targets, Edited by Sharmila Bapat Copyright ď›™ 2009 John Wiley & Sons, Inc.
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