Gross cystic disease fluid protein-15

Gross cystic disease fluid protein 15 (GCDFP-15), also known as "prolactin-induced protein" or PIP, is a protein produced by salivary sweat and tear glands. PIP binds to aquaporin-5 in salivary and lacrimal glands. This process leads to the transport of aquaporin-5 into the apical membrane. PIP has binding sites for actin. The production of PIP is stimulated by prolactin and androgens in the salivary, lacrimal and sweat glands and slowed down by estrogens.
In histological diagnostics, antibodies directed against GCDFP-15 are used as immunohistochemical diagnostic markers for apocrine and eccrine sweat glands, accessory salivary glands and mammary glands.

1. Hantschke M et al (2016) Immunohistological techniques. In: L. Cerroni et al. histopathology of the skin. Springer Publishing House Berlin-Heidelberg p. 30.
2. Hayashi T et al (2015) Low-grade cylindromatous adnexal carcinoma with unusual histopathological features: report of a case with comparative immunohistochemical study and meta-analysis of the literature. J Cutan Pathol doi: 10.1111/cup.12597.
3. Liu F et al (2015) Cutaneous metastases from gastric adenocarcinoma 15 years after curative gastrectomy. An Bras Dermatol 90(3 Suppl 1):46-50.
4. McClain CM et al (2015) Hidradenoma papilliferum associated with pregnancy: a case report. J Cutan Pathol doi: 10.1111/cup.12586.