Lieber C.M. et al. were the first to detect protein and single virus particles with the use of a Si-NW-sensor: a multiplex analysis was conducted of a prostate-specific antigen (PSA), a carcinoembryonic antigen (CEA) and mucin-1, a transmembrane glycoprotein associated with bladder cancer [15,28]. The gene discussed is CEACAM5; the disease is urinary bladder carcinoma.