RESEARCH ARTICLE Attenuated XPC Expression Is Not Associated with Impaired DNA Repair in Bladder Cancer

Bladder cancer has a high incidence with significant morbidity and mortality. Attenuated ex-pression of the DNA damage response protein Xeroderma Pigmentosum complementation group C (XPC) has been described in bladder cancer. XPC plays an essential role as the main initiator and damage-detector in global genome nucleotide excision repair (NER) of UV-induced lesions, bulky DNA adducts and intrastrand crosslinks, such as those made by the chemotherapeutic agent Cisplatin. Hence, XPC protein might be an informative bio-marker to guide personalized therapy strategies in a subset of bladder cancer cases. There-fore, we measured the XPC protein expression level and functional NER activity of 36 bladder tumors in a standardized manner. We optimized conditions for dissociation and in vitro culture of primary bladder cancer cells and confirmed attenuated XPC expression in approximately 40 % of the tumors. However, NER activity was similar to co-cultured wild type cells in all but one of 36 bladder tumors. We conclude, that (i) functional NER deficien-cy is a relatively rare phenomenon in bladder cancer and (ii) XPC protein levels are not use-ful as biomarker for NER activity in these tumors