Methods using chemotherapy drugs promote targeting of S. typhimurium A1-R of melanoma, thereby enhancing efficacy against the melanoma PDOX. A metastatic melanoma obtained from the right chest wall of a patient was previously established orthotopically in the right chest wall of nude mice as a patient-derived orthotopic xenograft (PDOX) model. We previously showed that the combination of tumor targeting Salmonella typhimurium A1-R (S. typhimurium A1-R) and chemotherapy was highly effective against the melanoma PDOX. In the present study, we investigated the mechanism of the high efficacy of this combination. Combination therapy significantly increases S. typhimurium A1-R tumor targeting alone (S. typhimurium A1-R+TEM: p<；0.01, S. typhimurium A1-R+VEM: p<；0.01).
