Attributes of Oct4 in stem cell biology: Perspectives on cancer stem cells of the ovary

Journal of Ovarian Research (Impact Factor: 2.43). 11/2012; 5(1):37. DOI: 10.1186/1757-2215-5-37
Source: PubMed


Epithelial ovarian cancer (EOC) remains the most lethal of all the gynaecological malignancies with drug resistance and recurrence remaining the major therapeutic barrier in the management of the disease. Although several studies have been undertaken to understand the mechanisms responsible for chemoresistance and subsequent recurrence in EOC, the exact mechanisms associated with chemoresistance/recurrence continue to remain elusive. Recent studies have shown that the parallel characteristics commonly seen between embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSC) are also shared by a relatively rare population of cells within tumors that display stem cell-like features. These cells, termed 'cancer initiating cells' or 'cancer stem cells (CSCs)' have been shown not only to display increased self renewal and pluripotent abilities as seen in ESCs and iPSCs, but are also highly tumorigenic in in vivo mouse models. Additionally, these CSCs have been implicated in tumor recurrence and chemoresistance, and when isolated have consistently shown to express the master pluripotency and embryonic stem cell regulating gene Oct4. This article reviews the involvement of Oct4 in cancer progression and chemoresistance, with emphasis on ovarian cancer. Overall, we highlight why ovarian cancer patients, who initially respond to conventional chemotherapy subsequently relapse with recurrent chemoresistant disease that is essentially incurable.

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Available from: Nuzhat Ahmed, Feb 17, 2015
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    • "Additionally supporting our thesis about ovarian embryonic stem cells reactivation in SBT and OSC was the expression of Oct-4 embryonic stem cell marker in the early normal ovarian development , as well as in tumorous tissue of SBT and OSC. Our finding of Oct-4 positivity during ovarian embryonic development accords with its pivotal role in the maintenance of self-renewal and pluripotency of embryonic stem cells (Samardzija et al., 2012). Expression of Oct-4 in SBT and OSC reveals the presence of subpopulation of cells which is either dedifferentiated or which silently retained stemness from the period of ovarian developmental. "
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