Detecting expression of keratins 8/18 in human HaCaT keratinocytes

Differences in treatment solution affect the efficiency of keratin extraction in cultured human squamous cell carcinomas, malignant melanomas, and melanocytes. Using an aqueous solution that is excellent for cultured cells, we focused this study on the expression of keratin subunits in the spontaneously immortalized human keratinocyte cell line HaCaT. We extracted several keratin (K) subunits, namely K4, K7, K8, K15, K17, and K18, and ATP synthase alpha-chain, in addition to those previously reported by Boukamp et al. (J Cell Biol 1988;106:761-771) in human HaCaT keratinocytes. In particular, K8 and K18 subunits, which are related to tumorigenesis, may be very important subunits within the specificities of immortalized HaCaT cells. Vimentin, which is frequently co-expressed in cultured epithelial cell lines, was not expressed.