The molecular mechanism and regulatory pathways of cancer stem cells

Malignant cancer is among the top of the life-threatening conditions, challenging humanity for a long time. Traditional methods of cancer therapy include surgery, chemotherapy, and radiotherapy, which aim to remove/destroy cancer cells. Although theoretically very promising, none of these methods can effectively eradicate cancer, the reason for which can be attributed to our incomplete understanding of the mechanism of cancer metastasis and recurrence. In recent years, researchers have proposed the theory of cancer stem cell (CSC). CSC is a small population of tumor cells that have unlimited self-renewal ability, exhibit a strong resistance to chemotherapy and radiotherapy, and have been proved to be the core reason of cancer metastasis and recurrence. CSC theory provides a deep insight into malignant tumorigenesis that brings new hope for tumor therapy. In this paper, we intend to discuss the development of CSC theory and summarize the regulatory pathways involved in CSC origin and self-renewal, which might be of assistance in the future development of malignant cancer therapy.