The effect of combination therapy of radiation and Z-100, an arabinomannan on tumor growth in mice.

The effect of radiation combined with intraperitoneal administration of Z-100, an immunomodulatory arabinomannan extracted from Mycobacterium tuberculosis, was studied using Meth A fibrosarcoma in BALB/c mice and metastasis of Lewis lung carcinoma, 3LL, in C57BL/6 mice. In mice bearing Meth A fibrosarcoma, a moderate degree of growth inhibition was observed in the group of single therapy with Z-100 or radiation (10 Gy). When radiation was combined with Z-100, the tumor growth was significantly inhibited. In mice bearing 3LL, slight inhibition of pulmonary metastasis was observed in the group of single therapy, while significant degrees of inhibition of primary tumor growth and pulmonary metastasis were observed in the combination group. This suggests the usefulness of combined use of Z-100 in radiation therapy.