Jacob, Francis, Ukegjini, Kristjan, Fink, Daniel A., Hacker, Neville F., Heinzelmann-Schwarz, Viola A., Nixdorf, Sheri, Ford, Caroline E., Olivier, Jake, Caduff, Rosmarie, Scurry, James P., Guertler, Rea, Hornung, Daniela, Mueller, Renato. Public Library of Science; 2012. Loss of secreted frizzled-related protein 4 correlates with an aggressive phenotype and predicts poor outcome in ovarian cancer patients.