William B. Coley developed bacterial
therapy of
cancer more than 100 years ago and had clinical success. James Ewing, a very famous
cancer pathologist for whom the
Ewing sarcoma is named, was Coley's boss at Memorial Hospital in New York and terminated Coley's bacterial
therapy of
cancer. A
tumor from a patient with soft-tissue
Ewing's sarcoma, who failed
doxorubicin (DOX)
therapy, was previously implanted in nude mice to establish a patient-derived orthotopic xenograft (PDOX) model. In the present study, the
Ewing's sarcoma PDOX was treated with
tumor-targeting S. typhimurium A1-R expressing green fluorescent (GFP), alone and in combination with DOX. S. typhimurium A1-R-GFP was detected in the
tumors after intratumor (i.t.) or intravenous (i.v.) injection. The combination of S. typhimurium A1-R and DOX significantly reduced
tumor weight (37.8 ± 15.6 mg) compared to the untreated control (73.8 ± 10.1 mg, P < 0.01). S. typhimurium A1-R monotherapy-treated
tumors tended to be smaller (50.9 ± 17.8 mg, P = 0.051). DOX monotherapy did not show efficacy (66.3 ± 26.4 mg, P = 0.82), as was the case with the patient. The PDOX model faithfully replicated the DOX resistance the
Ewing's sarcoma had in the patient. S. typhimurium A1-R converted the
Ewing's sarcoma from DOX resistant to sensitive. One can only wonder how bacterial
therapy and
immunotherapy of
cancer would have developed over the past 80 years if Ewing did not stop Coley.