Urine was collected into 50ml falcon tubes and kept on ice during transport. Cells were pelleted by centrifugation (400g for 10 minutes at RT). Supernatant was aspirated and cells were resuspended in 500l PBS and 1.5ml of lysis buffer (DNeasy Blood and Tissue kit (Qiagen) per each 50ml falcon tube. 100l of Proteinase K were added to each tube, vortexed and incubated at 56°C for 25 min. 10l of RNAse A were added to each sample and incubated for 5 minutes. DNA was extracted using the DNeasy Blood and Tissue kit (Qiagen).