Expression of ERp29, an endoplasmic reticulum secretion factor in basal-cell carcinoma.

The role of endoplasmic reticulum (ER)-stress proteins in the pathogenesis of neoplasia remains obscure. ERp29 encodes for an ER protein that is thought to facilitate the transport of secretory proteins in the early secretory pathway. ERp29 is expressed at varying levels in virtually every tissue tested, yet its precise role remains obscure. To test if ERp29 is associated with the pathogenesis of skin cancer, in the present study we have assessed the expression of ERp29 in basal-cell carcinoma of the skin. A bank of 104 basal skin carcinoma, including 50 nodular, 29 infiltrating, 15 superficial, 7 sclerosing, 2 fibroepithelial, and 1 pigmented cell carcinoma, were assessed by immunohistochemistry for ERp29 expression. Thirty-nine (37.5%) of the samples tested expressed ERp29 with the infiltrating carcinomas displaying more intense (++,+++) immunoreactivity (6/29, P < 0.05) and the superficial carcinomas exhibiting the less intense anti-ERp29 staining (1/15, P < 0.05). Collectively our results suggest that ERp29 is expressed in a subset of basal-cell carcinoma of the skin with the infiltrating carcinomas exhibiting the highest incidence of immunopositivity. The role of ERp29 in the pathogenesis of the disease and its potential diagnostic value should be explored in future investigations.