Methylcholanthrene-induced papillomas were established as transplantable lines in immunodepressed isogeneic mice. Primary papillomas gave rise on transplantation to surfacegrowing papillomas, keratinous, sebaceous, and mixed cysts, suggesting multipotentiality of the premalignant epithelium. Cyst linings could be reverted to surface papillomas by transplantation to split-thickness graft beds. Regardless of morphology, various generations of papilloma lines shared antigenic specificities. Increases or decreases of immunogenicity and immunosensitivity were found in different generations of the same papilloma.
The pattern of progression to cancer suggested that transformation and subsequent progression was an individual characteristic not shared equally by all progeny of a particular primary papilloma.
The transplantable papilloma model offers an opportunity for studies of differentiation, tumor progression, and interrelationships with host immunity.
This study was aided by Grant IC-46 from The American Cancer Society.