Figure 9 shows that thereis a linear dependence between the normalized Raman intensity of tyrosinevibration at 1618 cm–1 on the surface of the normaland cancer cells and the HER2 and EGFR statuses determined by conventionalbiological methods. It indicates that the HER2 expression evaluatedby the Raman method in the cells correlates in an excellent way withthe conventional biological methods of HER2 determination.28 Here, ERBB2 is linked to cancer.