Cytopathic effects in primary epithelial cultures derived from the human prostate.

Normal, benign, and malignant human prostatic tissue was cultivated in vitro. Cytopathic effects in derived epithelial cells were examined. Light microscopy revealed polykaryocyte formation, vacuolation, cytoplasmic bridges and processes, nuclear inclusions, increased acid phosphatase activity at the cell membrane of polykaryocytes as compared to mononuclear cells, and cell rounding and clumping. Electron microscopy of the polykaryocytes showed nuclear membrane proliferation and protrusion, scarlike nuclear inclusions containing microfibrils, and virus-like particles similiar to viral nucleoids and nucleocapsids. The latter were also observed in the cytoplasm. The above alterations are similar to those induced by known herpesviruses. The significance of these changes, the possibility of the presence of a latent herpesvirus in the prostate, and its role in neoplastic disease are postulated.