HLA-G expression in basal cell carcinomas of the skin recurring after radiotherapy.
Basal cell carcinoma (BCC) of the skin represents the most common malignancy in the fair-skinned population worldwide. HLA-G is one of the molecules implicated in immunotolerance. To investigate the role of HLA-G in recurring BCCs, we constructed a tissue microarray containing 38 primary BCCs that underwent radiotherapy and 14 secondary BCCs recurring on the primary site after radiotherapy, and evaluated the HLA-G protein expression by immunohistochemistry. The HLA-G protein was most frequently expressed in aggressive sclerosing BCCs. Nodular BCC demonstrated the strongest HLA-G expression. Interestingly, tumor infiltrating mononuclear cells (TIMC) expressed the HLA-G molecule in BCCs that showed no recurrence. After comparing primary BCCs and BCCs relapsed after radiotherapy, we observed decreased HLA-G expression on tumor cells and the loss of HLA-G expression on TIMC in relapsed BCCs. After radiotherapy, immunobiology of BCC may change resulting in the down-regulation of HLA-G expression on tumor and on tumor-infiltrating cells.
Urosevic
M
M
Department of Dermatology, University Hospital Zurich, Switzerland. mirjana.urosevic@usz.ch
Kempf
W
W
Zagrodnik
B
B
Panizzon
R
R
Burg
G
G
Dummer
R
R
D002280:Basal Cell Carcinoma / Q000276:immunology* / Q000532:radiotherapy; D005500:Follow-Up Studies; D006680:HLA Antigens / Q000378:metabolism*; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I / Q000378:metabolism*; D006801:Humans; D007108:Immune Tolerance; D007124:Immunoenzyme Techniques; D009364:Neoplasm Recurrence, Local / Q000276:immunology*; D012189:Retrospective Studies; D012878:Skin Neoplasms / Q000276:immunology* / Q000532:radiotherapy
D006680:HLA Antigens; D059951:HLA-G Antigens; D015395:Histocompatibility Antigens Class I