EPCAM and cancer: Through a similarapproach, substituting ssDNA with a peptide as the linker, SERS imagingof caspase 3 in live cells and tissues was obtained. Guo et al. designed the tetrahedron probe to detect telomerase(TE) and epithelial cell-adhesion molecule (EpCAM) simultaneouslyin living cells and differentiated the cancer cell lines HeLa, MCF-7,and normal primary uterine fibroblast cells. Assembled by DNA frames, the tetrahedron probe consisted of three15 nm AuNPs and two 30 nm AuNPs.