Abstract
The ERCC1 protein (excision repair cross-complementing rodent repair deficiency, complementation group 1) forms a heterodimer with the Xeroderma pigmentosum group F (XPF) endonuclease (also known as ERCC4), and the heterodimeric endonuclease catalyzes the 5′ incision in the process of excising the DNA lesion. The ERCC1–XPF heterodimer has an important role in genome maintenance. While most of the DNA repair proteins function only in a specific repair pathway, ERCC1–XPF is involved in multiple DNA repair pathways and telomere maintenance, making this heterodimer not only an attractive therapeutic target, but also a biomarker to predict treatment outcome (Fig. 2.3).