Expression And Correlation Of Hla-G And Shla-G As Prognostic Factors In Renal Cell Carcinoma.

e16066 Background: many studies have related HLA-G to increased tumorigenicity. Serum HLA-G (sHLA-G) has been detected in plasma of patients with malignant diseases. Levels of sHLA-G are higher in patients with Renal Cell Carcinoma (RCC) compared to Healthy Controls (HC). Previous studies have found HLA-G expression in 45-60% of the RCC lesions, but not in normal kidney tissue. We determined expression of HLA-G in surgery specimens, levels of sHLA-G in patients and HC, correlation between levels of sHLA-G and clinical parameters (sex, age, subtypes, progression and survival) and between HLA-G/sHLA-G. Methods: histological samples of patients from HCU Lozano Blesa in Zaragoza (Spain) with histologically confirmed RCC by nephrectomy, of every subtypes and stages. Patients who received prior chemotherapy or radiotherapy were excluded. Blood serum is obtained during surgery and in HC. Cytokeratin, vimentin, Ki-67 and HLA-G were analyzed. sHLA-G were determined using ELISA test kits. Results: A sample of 33 patients obtained from Jul-2008 to dec-2009. 67'7% were male (37-85 y). 85% of patients had localized disease at diagnosis with predominant histology of Clear Cell Carcinoma. After 5y follow-up 20% progressed and 10 deaths were observed. Levels of sHLA-G in patients with RCC were higher than the HC (46'6 U/ml vs 18'3 U/ml). Pearson correlation test with a score of 0.41 was made, appreciating a positive relationship between patients and HC. Spearman Rho test was analyzed between sHLA-G and HLA-G in tumor specimen (0'4533 positive relationship). There is a positive relationship between sHLA-G patients with advanced stage and progression (Spearman Rho correlation 0'6589 and 0'255 respectively). The higher value of sHLA-G was, the more advanced tumor stages and progression rates were found. Conclusions: The degree of HLA-G expression in tumor tissue of RCC could influence the evolution of this disease, and may develop as an useful marker in clinical practice. Because of direct relationship between plasma sHLA-G and HLA-G in nephrectomy tissue, an easy determination by blood collection is allowed. From this data, future studies with larger samples are necessary to take into account the role of sHLA-G as a prognostic factor for RCC.