The biphasic nature of a human amelanotic melanoma tumour line HT-18

The morphological features of a human amelanotic melanoma tumour line, HT-18 was studied in vitro. Primary cultures show that the tumour cells are biphasic with respect to their differentiation as revealed by light microscopy, SEM and TEM. Most of the cells show numerous processes resembling neuronal dendrites. The cytoplasm contains stage I and II melanosomes, occasionally melanosomes showing irregular pigmentation. According to these observations it appears that the HT-18 cells are at an earlier phase of differentiation showing both melanogenic and neurogenic activity.