The significance of plasma and urinary vesicular miRNAs and PD-L1 in predicting the response to immunotherapy in advanced renal cell carcinoma

Immunotherapy with checkpoint inhibitors (Cl) is also the standard treatment in advanced renal cell carcinoma (RCC) ( 1 ). The Cls are monoclonal antibodies that target immune checkpoint proteins on cancer and immune cells ( 1,2). In cancer immune cells lose the ability to recognize cancer cells and destroy them (3). Some patients treated with Cls have durable responses, on the other hand some don ·t respond at all. As of now many predictive biomarkers are being studied, which would predict response to Cls. Due to the stability, presence in different body fluids and expression independent of age and sex. extracellular esicle microR A (EV-miR A) is potentially promising biomarker. Most patients with advanced RCC have high concentration of circulating plasma EVs, which indicates their direct involvement with cancer progression (7). EV-miRNA can affect posttranscriptional and posttranslational expression of genes. Different miRNAs were studied in patients with RCC. In these studies expression of miRNA was compared between patients with RCC and healthy controls and preoperatively and postoperatively in patients with RCC. No studies evaluated changes in expression of miRNA in relation to the response to treatment ( 4). In patients with advanced RCC, expression of PD-Ll in tumour isn't reliable predictive marker for response to the treatment with Cls. According to the recent research malignant cells secrete EVs with PD-LI expressed on their membrane (EV-PD-LI). Therefore, EV­PD-L 1 could be potential liquid biomarker in RCC (5,6), The purpose of our research is to discover the association between the expression of miRNA and PD-LI in plasma and urine and radiological objective response to treatment of patients with advanced RCC in the intermediate-risk and poor-risk disease group in first 16. weeks of treatment, treated in first or second line with Cls.