To investigate this, fibroblasts from XP or CS patients defective for individual proteins involved in GG-NER and/or TC-NER, and from a healthy control, were treated with increasing doses of cisplatin for 24 h, lysed, and probed for MK2 pathway activation by immunoblotting for the active, phosphorylated form of MK214. Here, MAPKAPK2 is linked to Cowden syndrome 1.