2Institute for Urology and Reproductive Health, Sechenov First Moscow State Medical University, 119991 Moscow, Russia
3Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, 117997 Pushchino, Moscow Region, Russia
4Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119991 Moscow, Russia
5Institute of Molecular Medicine, Sechenov First Moscow State Medical University, 119991 Moscow, Russia
6Department of Biotechnology, Sirius University of Science and Technology, 354340 Sochi, Russia
7Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7XH, Surrey, UK
* To whom correspondence should be addressed.
Received April 28, 2022; Revised June 6, 2022; Accepted June 15, 2022
Renal cell carcinoma (RCC) is the most common urological malignancy with a high mortality and low detection rate. One of the approaches to improving its diagnostics may be the search for new non-invasive biomarkers in liquid biopsy and development of more sensitive methods for their detection. Cancer-retina antigens, which are known to be aberrantly expressed in malignant tumors, are present in liquid biopsy at extremely low concentrations. Using the developed multiplex immunoassay with a detection limit of 0.1 pg/ml, urine and serum samples of 89 patients with RCC and 50 non-cancer patients were examined for the presence of cancer-retina antigens (arrestin, recoverin, rhodopsin kinase, and transducin); the difference between the RCC and control groups was evaluated with the χ2 test. The results showed high diagnostic efficiency of a combination of arrestin and recoverin: at a threshold of 0.1 pg/ml, the sensitivity was 96%, specificity 92%, and AUC = 0.96 (95% confidence interval, 0.93-0.99). Seven days after nephrectomy, the concentration of the antigens returned to the level characteristic of the control group. Therefore, arrestin in a combination with recoverin can serve as a diagnostic non-invasive urinary biomarker of RCC.
KEY WORDS: cancer-retina antigens, renal cell carcinoma, immunoassay, magnetic particles