Conjugate (MTC-220) of muramyl dipeptide analogue and paclitaxel prevents both tumor growth and metastasis in mice.

1 (MTC-220), a conjugate of paclitaxel and a muramyl dipeptide analogue, has been synthesized as a novel agent of dual antitumor growth and metastasis activities. In vitro and in vivo tests show that 1 retains its ability to inhibit tumor growth. It is superior to paclitaxel in its ability to prevent tumor metastasis in Lewis lung carcinoma and 4T1-tumor-bearing mice. The present studies indicate that 1 suppresses myeloid derived suppressor cell accumulation in the spleen and bone marrow of tumor-bearing mice and also represses inflammatory cytokines in tumor tissue. These results demonstrated that 1 could be a potential therapeutic and preventive agent for cancer growth and metastasis.