TP53 and cancer: Nanobodies containing only a heavy chain variable region (VHH) but still retain antigen specificity and high affinity523 have proven their value in cancer therapy and diagnosis in recent years.524–526 Two p53-binding nanobodies, Nb3 and Nb139, were obtained by immunization and panning procedures.527 Nb3 binds to the “structural mutations” R175H and R282W, and Nb139 binds to both wild-type and mutant p53, inhibiting the transcriptional capacity of p53.