Abstract
Objective
In this review, several interlinking issues related to cancer stem cells (CSCs) in malignant solid tumors are sequentially discussed.
Methods
A literature search was performed using PubMed, Web of Science and the Cochrane library, combining the words CSCs, solid tumor, isolation, identification, origination, therapy, target and epithelial–mesenchymal transition.
Results
Because a primary problem is the isolation of CSCs, we first analyzed the advantages and disadvantages of recently used methods, which were mostly based on the physical or immunochemical characteristics of CSCs. Once CSCs are isolated, they should be identified by their stem cell properties. Here, we suggest how to establish a standard identification strategy. We also focused on the origination hypotheses of CSCs. The supporting molecular mechanisms for each theory were thoroughly analyzed and integrated. Especially, epithelial– mesenchymal transition is an increasingly recognized mechanism to generate CSCs that are endowed with a more invasive and metastatic phenotype. Finally, we discuss putative strategies of eliminating CSCs as effective cancer therapies.
Conclusion
After several interlocking issues of CSCs are thoroughly clarified, these CSCs in solid malignant tumors may specifically be targeted, which raises a new hope for eliminating these tumors.
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Abbreviations
- CSCs:
-
Cancer stem cells
- DGC:
-
Density-gradient centrifugation
- EMT:
-
Epithelial to mesenchymal transition
- FACS:
-
Fluorescent activated cells sorting
- HCSCs:
-
Hepatic cancer stem cells
- HNSCs:
-
Hepatic normal stem cells
- NOD/SCID:
-
Non-obese diabetic/severe combined immunodeficiency
- NSCs:
-
Normal stem cells
- NSP:
-
Non side population
- SP:
-
Side population
- SP-HNCs:
-
Side population of hepatic normal cells
- SP-HCCs:
-
Side population of hepatic cancer cells
- TDDS:
-
Targeting drug delivery systems
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Acknowledgments
Sincere thanks go to Fu-qin Zhang (the Fourth Military Medical University, China) for data collection. This study was supported by the National Natural Science Foundation of China (No. 81170419, 81172061, 81000309, 81272648, 81001695). The funders had no role in study design, data collection and analysis, or preparation of the manuscript.
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Wei-hui Liu, Nan You, Ning Zhang, Hong-tao Yan, Tao Wang, Zhu Huang equally contributed to this work. Hong-bao Liu, Li-jun Tang were co-corresponding authors.
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Liu, Wh., You, N., Zhang, N. et al. Interpretation of interlocking key issues of cancer stem cells in malignant solid tumors. Cell Oncol. 35, 397–409 (2012). https://doi.org/10.1007/s13402-012-0110-8
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DOI: https://doi.org/10.1007/s13402-012-0110-8