The CRISPR-Cas9 system: a promising tool for discovering potential approaches to overcome drug resistance in cancer.

The CRISPR-Cas system was identified in bacteria as an immune defense mechanism against threats from the external environment. A common form of this system, called CRISPR-Cas9, is now widely used in gene editing, especially in mammalian cells. Through CRISPR-Cas9, gene knock-ins or knock-outs have become more feasible, thus deepening our understanding of the mechanisms of human diseases, including cancers, and suggesting possible treatment strategies. In this review, we discuss how CRISPR-Cas9 can be used as a tool to discover more about drug-resistance in cancers, including both the underlying mechanisms and ways to overcome them.