Stem cells in human breast cancer

Department of Pathology, Ribeirão Preto Medical School, University of São Paulo, Campus Universitário Monte Alegre, Ribeirão Preto, SP, Brazil.
Histology and histopathology (Impact Factor: 2.1). 03/2010; 25(3):371-85.
Source: PubMed


Increasing data support cancer as a stem cell-based disease. Cancer stem cells (CSCs) have been found in different human cancers, and recent evidence indicates that breast cancer originates from and is maintained by its own CSCs, as well as the normal mammary gland. Mammary stem cells and breast CSCs have been identified and purified in in vitro culture systems, transplantation assays and/or by cell surface antigen identification. Cell surface markers enable the functional isolation of stem cells that can initiate and propagate tumorigenesis in mammary gland. These observations have dramatic biological and clinical significance due to increasing evidence suggesting that the recurrence of human cancer and treatment failure may reflect the intrinsic quiescence and drug resistance of CSCs. Thus, the CSC hypothesis provides fundamental implications for understanding breast carcinogenesis and for developing new strategies for breast cancer prevention and therapy for advanced disease. Further strategies to isolate breast CSCs, to find additional trustworthy surface markers, and to compare gene expression pathways profiles with their normal stem cells counterparts are necessary to more accurately define putative breast cell-lineage markers for the different cell types present in the mature mammary gland and to identify potential therapeutical targets in breast cancer. This review discusses the current knowledge about stem cells and CSCs, focusing on mammary stem cells and breast CSCs, and their consequences for breast tumorigenesis and implications for breast cancer susceptibility, prognosis, and treatment.

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Available from: Lucinei Roberto Oliveira
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    • "Accumulating experimental and clinical evidence indicate that breast cancer arises from mammary stem/progenitor cell populations [41]–[43]. Although the possible involvement of breast cancer stem/progenitor cells in TAM resistance has been proposed [44] and demonstrated [45], the exact function and the underlying mechanism of breast cancer stem/progenitor cells in TAM resistance remain largely unknown. "
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    • "CSCs are thought to play a role in recurrence and metastasis of TNBC [25]. CSCs are predicted to be the cell origin of the tumor and responsible for tumor progression, relapse and metastasis due to their self-renewal capacity and limitless proliferative potential, as well as invasion and migration capacity [43]. Although CSCs comprise a small amount of the cells within a tumor, they can be resistant to radiotherapy and chemo-therapeutic agents, probably because of their quiescence. "
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    • "The risk with respect to old age is already well known due to the duration allowing for the accumulation of mutations in the cells, mainly in the pool of stem cells, which multiply slowly. Over time, these cells acquire the necessary mutations to maintain a balance between them and the organ microenvironment [22]. Another significant prognostic factor was a history of DM 2 (p=0.014) and chronic pancreatitis (p=0.02), which demonstrated that they may be risk factors for pancreatic cancer. "
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