Cancer Stem Cells: A Review of Potential Clinical Applications

Abstract

Context.-Cancer stem cells (CSCs) comprise a minor cell population in a tumor; however, they possess selfrenewal capacity and are responsible for tumor recurrence and the emerging issue of tumor resistance. Despite recent advances in the study of pathogenesis and mechanisms of CSC-mediated disease recurrence and multidrug resistance, many questions remain unanswered.Objectives.-To provide an overview of CSC theory and to describe major methods of CSC detection and isolation, with the emphasis on those techniques that are potentially relevant in clinical laboratory practice. Particular attention is given to CSC markers, such as cancer testis antigens, which could become promising targets in the development of immunotherapy in settings of minimal residual disease.Data Sources.-The review is based on analysis of peerreviewed literature cited in PubMed, as well as preliminary results of studies conducted in our laboratory.Conclusions.-Despite a lack of consensus in the scientific community on research methodology, CSCs have demonstrated significant potential as therapeutic targets in the treatment of cancer. Further research of CSC biology and markers will eventually lead to the development of novel therapeutic approaches for targeting these cells to treat resistant and recurrent tumors and minimal residual disease.

Translational potential of cancer stem cells: A review of the detection of cancer stem cells and their roles in cancer recurrence and cancer treatment

“…Different analytical methods and techniques have been used to detect the traits of CSCs. Commonly used methodologies for detection and isolation of CSCs include functional, image-based, molecular, cytological sorting, filtration approaches and xenotransplantation [21][22][23][24]. These approaches have been developed on the basis of unique features of CSCs.…”

Cancer-Initiating Cells from Colorectal Cancer Patients Escape from T Cell–Mediated Immunosurveillance In Vitro through Membrane-Bound IL-4

“…Moreover, a preferential induction in vitro of Th2-type responses occurred following the coculture of CICs with autologous PBMCs (10). Cancer-testis Ags have been found to be expressed by mesenchymal stem cells and to regulate the epithelial-to-mesenchymal transition, a process involved in development of metastases; thus these Ags may possibly have a role in the stemness properties of cancer cells and could represent target molecules for immunotherapy (11). Nevertheless, antitumor immunity could be attenuated by tumor-related immunosuppressive mechanisms that have been described in association with CICs isolated from melanoma or GBM (12)(13)(14).…”

Cancer Stem-Like Cells in Glioblastoma

“…Other methods such as affinity chromatography, panning, and aptamers also use the immunological recognition principle (44,47,48). In GBM, some of the most useful markers are SOX2, OCT4, NANOG, CD133, and ABCG2 (44,45,53). However, no single marker can be considered a gold standard, and, therefore, a series of markers is mandatory to validate the stemness status.…”