Squamous epithelial proliferation induced by walleye dermal sarcoma retrovirus cyclin in transgenic mice

The study investigated the role of the Walleye dermal sarcoma virus (WDSV) cyclin in cell proliferation by generating transgenic mice expressing the retroviral cyclin in squamous epithelia. These mice exhibited smaller size, reduced hair follicles, and impaired lactation in females. Upon injury, they developed severe squamous epithelial hyperplasia and dysplasia, with characteristics of neoplastic squamous epithelium. The hyperplastic epithelium showed abnormal differentiation and stained positive for cytokeratin, with the rv-cyclin protein present in the thickened basal cell layers. This research provided the first evidence that the WDSV rv-cyclin is a potent stimulator of eukaryotic cell proliferation and can induce hyperplastic skin lesions.