ERCC1 - Relevance in Chemotherapy

Relevance in Chemotherapy

Measuring ERCC1 activity may have utility in clinical cancer medicine because one mechanism of resistance to platinum chemotherapy drugs correlates with high ERCC1 activity. Nucleotide excision repair (NER) is the primary DNA repair mechanism that removes the therapeutic platinum-DNA adducts from the tumor DNA. ERCC1 activity levels, being an important part of the NER common final pathway, may serve as a marker of general NER throughput. This has been suggested for patients with gastric, ovarian, colorectal and bladder cancers. In Non-small cell lung carcinoma (NSCLC), surgically removed tumors that receive no further therapy have a better survival if ERCC1-positive than if ERCC1-negative. Thus ERCC1 positivity is a favorable prognostic marker, referring to how the disease will proceed if not further treated. ERCC1-positive NSCLC tumors do not benefit from adjuvant platinum chemotherapy. However, ERCC1-negative NSCLC tumors, prognostically worse without treatment, derive substantial benefit from adjuvant cisplatin-based chemotherapy. High ERCC1 is thus a negative predictive marker, referring to how it will respond to a specific type of treatment.

ERCC1 genotyping in humans has shown significant polymorphism at codon 118. These polymorphisms may have differential effects on platinum and mitomycin damage.