DNA repair systems operate in all living cells to manage a variety of DNA lesions. Nucleotide excision repair (NER) is implemented in cases where bulky helix-distorting lesions occur, such as those brought about by UV and certain chemicals. Excision Repair Cross Complementing 1 (ERCC1) forms a complex with ERCC4/XPF, which acts as the 5’ endonuclease required to excise the lesion. ERCC1-XPF is also required for repair of DNA interstrand crosslinks (ICLs) and involved in repair of double strand breaks. Research studies have shown that expression of ERCC1 is related to survival rate and response to chemotherapeutic drugs in several human cancers including non-small cell lung cancer (NSCLC).