Cancer Stem Cells: Targets for treatment of malignancies to overcome drug resistance

Context: In spite of all advancements in anticancer drugs, most tumors have been found to relapse and metastasize to other organs, causing resistance to therapy. It is believed that cancer stem cells (CSCs), due to their special properties like self-renewal and differentiation into heterogeneous cancer cells, could be involved in cancer recurrence and anticancer treatment resistance. Evidence Acquisition: Studies indicate that different molecular mechanisms like signaling pathways, cell surface markers, tumor microenvironment and miRNAs are responsible for drug resistance property of cancer stem cells. Hence, detailed knowledge of these mechanisms could be of help in finding an effective therapeutic strategy to target this group of cells in order to overcome the issue of tumor relapse and drug resistance Results: Taken together, cancer stem cells use various mechanisms to escape from immune system and other defensive obstacles like apoptosis to survive and induce drug resistance. This fact emphasizes the need for combination therapies in addition to targeting each aspect of these cells. Conclusions: It seems reasonable to conclude that finding effective ways to eliminate chemotherapy resistance needs more research and clinical trials in different cancers using various strategies targeting cancer stem cells’ properties.