TF and trichoblastoma: To investigate whether or not nuclear β-catenin and VDR expression correlated with tumour type in human skin tumours, we examined a panel of 59 human tumours, which were categorised as basal cell carcinomas or having elements of HF differentiation (trichofolliculomas (TF), trichoepithelioma (TE), or sebaceous TF (STF) (Table S4).