PSIP1 and prostate cancer: In a previous study we addressed this issue by evaluating 64 human sera that presented a monospecific DFS IIF pattern for the presence of antibodies to DFS70/LEDGF or its interacting partner MeCP2, a protein of approximately 70 kD that also displayed the DFS IIF pattern in HEp-2 cells and in advanced prostate cancer cells, which express high levels of both DFS70/LEDGF and MeCP2 [135].