These mutants demonstrated considerably reduced induction of host TNF‐α (a key mediator in bacteria‐mediated tumor therapy), yet retained the capacity for tumor multiplication and growth suppression, achieving accumulation in tumors of 109 colony forming units (cfu)/g of tumor, which was 1000 times higher than normal tissues in mice.86, 87 The outcome was followed for tumor growth and mouse survival. The gene discussed is TNF; the disease is neoplasm.