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http://dx.doi.org/10.5352/JLS.2019.29.4.499

Characteristics of Cancer Stem Cells and Immune Checkpoint Inhibition  

Choi, Sang-Hun (Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University)
Kim, Hyunggee (Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University)
Publication Information
Journal of Life Science / v.29, no.4, 2019 , pp. 499-508 More about this Journal
Abstract
Cancer stem cells (CSCs), which are primarily responsible for metastasis and recurrence, have self-renewal, differentiation, therapeutic resistance, and tumor formation abilities. Numerous studies have demonstrated the signaling pathways essential for the acquisition and maintenance of CSC characteristics, such as WNT/${\beta}$-catenin, Hedgehog, Notch, B lymphoma Mo-MLV insertion region 1 homolog (BMI1), Bone morphogenetic protein (BMP), and TGF-${\beta}$ signals. However, few therapeutic strategies have been developed that can selectively eliminate CSCs. Recently, neutralizing antibodies against Cytotoxic T-lymphocyte associated protein 4 (CTLA-4) and Programmed cell death protein 1 (PD-1)/Programmed death-ligand 1 (PD-L1), immune checkpoint inhibitors (ICIs), have shown promising outcomes in clinical trials of melanoma, lung cancer, and pancreatic cancer, as well as in hematologic malignancies. ICIs are considered to outperform conventional anticancer drugs by maintaining long-lasting anti-cancer effects, with less severe side effects. Several studies reported that ICIs successfully blocked CSC properties in head and neck squamous carcinomas, melanomas, and breast cancer. Together, these findings suggest that novel and effective anticancer therapeutic modalities using ICIs for selective elimination of CSCs may be developed in the near future. In this review, we highlight the origin and characteristics of CSCs, together with critical signaling pathways. We also describe progress in ICI-mediated anticancer treatment to date and present perspectives on the development of CSC-targeting ICIs.
Keywords
Cancer stem cell; CTLA-4; Immune checkpoint inhibitor; PD-1; PD-L1;
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