For example, upregulated and active Notch1 has been found in basal and suprabasal cells in sebaceous glands during the early stage of epidermal stratification; a reduction in the number of HFs occurs in the absence of Notch1 signalling; and Notch1-3 have been identified in differentiating HF cells [94–96]. This evidence concerns the gene NOTCH1 and Hand-foot syndrome.