Tumoricidal effects of Mycobacterium ulcerans toxin on murine adenocarcinoma (C3HBA)

Fresh homogenized mammary gland adenocarcinoma (C3HBA) material was subcutaneously inoculated in the anterior right thigh of transplant host mice (C3H/HeJ). When tumors were palpable, the mice were separated into three groups. The test group received biweekly intratumoral injections of Mycobacterium ulcerans filtrate containing 40 mg of protein per ml. One control group received intratumoral injections of normal physiological saline, and the remaining group received no treatment at all. The survival rate of toxin-treated animals was 13.5% at 15 weeks when compared with the control groups. Additionally, tumor metastasis was apparently abrogated in test animals when compared to the control animals. Marked necrosis of the tumors in the test animals was noted by histological examination. Controls showed slight to moderate degrees of tumor necrosis. In this model Mycobacterium ulcerans toxin appears to have therapeutic value as an antitumor agent.