Is the cancer process caused by deletion of one or more differentiation genes normally activated by steroid hormones?

The hypothesis is proposed that: 1. Aflatoxin B1 and polycyclic hydrocarbon carcinogens cause the deletion of genes necessary for the production of a substance required for differentiation of the cell and activated by a steroid hormone possibly a corticosteroid. 2. Such genes could include genes for production of: glutamine transaminase, glutamine synthetase, genes involving vitamin A metabolism. 3. Deletion of any of these genes could cause the cell to remain in an undifferentiated and replicating state.