NUCLEOLIN and cancer: For in vivo use, DNA aptamers (anti-nucleolin, anti-MUC1, anti-EGFRvIII, anti-cancer cell-type-specific aptamers) and RNA aptamers (anti-PSMA aptamer) show perform well for cancer-specific detection using various imaging techniques (e.g., fluorescence, PET, SPECT, MRI, CT, and US) at the preclinical stage.