Non-Invasive Diagnostics of Renal Cell Carcinoma Using Ultrasensitive Immunodetection of Cancer-Retina Antigens

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Yuri M. Shlyapnikov^1,a*, Ekaterina A. Malakhova^1,b, Natalia V. Potoldykova^2,c, Yana A. Svetocheva^2,d, Andrei Z. Vinarov^2,e, Dmitry V. Zinchenko^3,f, Evgeni Yu. Zernii^4,g, Andrey A. Zamyatnin, Jr.^4,5,6,7,h, and Elena A. Shlyapnikova^1,i

¹Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia

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

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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.

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KEY WORDS: cancer-retina antigens, renal cell carcinoma, immunoassay, magnetic particles

DOI: 10.1134/S0006297922070070

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