Skin cancer, especially squamous cell carcinoma (SCC) is a frequent complication in patients with recessive dystrophic EB (RDEB) at sites of recurrent wound healing and scarring. These SCCs often have a poor prognosis due to their rapid invasive properties and the tendency to spread to other parts of the body. At present, very little is known about the molecular mechanisms responsible for this distressing situation.

SCC arises in keratinocytes, i.e. cells in the upper part of the skin. When keratinocytes become cancerous they invade through the lower layers of the skin to capillaries and lymph nodes. The group has noted that SCC cells specifically produce a substance called collagenase-13 (MMP-13), which is not found in normal keratinocytes. Dr Kähäri’s group has also shown that MMP-13 is responsible for the ability of SCC cells to invade through the lower layers of the skin and affect other body parts. They have found that by inhibiting the expression of MMP-13 by SCC cells in a mouse model, they can potentially inhibit SCC cell invasion and the growth of SCCs. Additionally, they have found that another substance produced in keratinocytes, matrix metalloproteinase-19 (MMP-19) is shut down when keratinocytes turn into cancer cells. It is believed that these two substances, MMP-13 and MMP-19, can be used both as diagnostic markers and as targets for treatment of SCCs in RDEB.