Expression of growth hormone receptor in benign and malignant cutaneous proliferative entities.

The skin has the necessary elements to respond to growth hormone (GH) and suffers clinical changes in the pathological circumstances of excess and deficiency of GH. The GH has been involved in the development of different types of human neoplasms. Based on these data, we have studied the GH receptor (GHR) expression in acrochordons, seborrheic keratosis, melanocytic nevi, histiocytomas, squamous cell carcinomas, basal cell carcinomas, and malignant melanomas by means of the immunohistochemistry with the monoclonal antibody MAb 263. All the entities showed immunoreactivity for GHR. In the histiocytomas, the expression of GHR in the keratinocytes of the hyperplastic epidermis coating the lesion showed a strong nuclear pattern, but the non-hyperplastic epidermis of the edges of the histiocytomas expressed GHR with a cytoplasmic pattern. In the basal cell carcinoma and squamous cell carcinoma, the immunoreactivity was weaker than in normal skin. In the squamous cell carcinoma, the intensity of immunostaining correlated directly with the grade of cellular differentiation. In conclusion, the GH may be involved in the development of different kinds of cutaneous neoplasms, and the intracellular localization of GHR may imply a functional significance, at least in the histiocytomas.