Loss of heterozygosity at cylindromatosis gene locus, CYLD, in sporadic skin adnexal tumours

Aim-The gene for familial cylindromatosis (CYLD) has been localised to chro mosome 16q, and has recently been cloned. Loss of heterozygosity (LOH) at 1 6q has also been demonstrated in sporadic cylindromas. The aim of this stud y was to investigate whether CYLD plays a role in the development of other skin appendage tumours. Methods-A total of 55 cases of skin adnexal tumours, comprising 12 differen t types, and a control group of 14 squamous cell carcinomas (SCCs) and basa l cell carcinomas (BCCs) were studied. Three microsatellites (D16S407 (16p) , D16S304 (16q), and D16S308 (16q)) were analysed for LOH after microdissec tion from paraffin wax embedded sections using laser capture microdissectio n. Results-In keeping with previous data, a proportion of cylindromas exhibite d LOH at markers on 16q, but not at 16p. The skin adnexal tumours showing a similar pattern included apocrine hydrocystomas, eccrine spiradenomas, and sebaceous adenoma. One case of syringoma showed LOH at 16q, and a further case at 16p, but not 16q. One case of eccrine hydrocystoma showed loss at 1 6p, but not 16q. The remaining tumours were either negative or non-informat ive. All tumours in the control group were either negative or non-informati ve, except for a single case of BCC showing LOH at 16q. Conclusion-CYLD may be involved in the development of skin adnexal tumours other than cylindromas.