Bacteria-derived minicells for cancer therapy

Bacteria are always a considerable tool for the cancer therapy. The bacteria-derived minicells are re-emerged as a promising drug delivery system for cancer therapy. The minicells are nano-sized, anucleated, non-dividing, and metabolically active cells produced by abnormal bacterial cell division that are able to transcribe and translate the gene of interest. Minicells encapsulate a wide range of chemotherapeutic and molecular drugs, si/shRNA, antigens and therapeutic toxins to precisely deliver them to the cancer cells through the easy modification of minicell surface with bi-specific antibodies against receptor-targeted cancer cells. Minicell-mediated chemotherapy may inhibit the growth of drug-resistant tumors and exhibits the potential to successfully deliver the chemotherapeutics into hypoxic and necrotic region in solid tumors. This novel approach significantly overcomes drug leakage and severe toxicity by enhancing targeting specificity and therapeutic index of drugs in cancer therapy. Many antibody-conjugated drug-loaded minicells are being investigated in clinical trials for cancer therapy. This review summarizes the advantages of bacteria-derived minicells as delivery systems for anti-cancer drugs or agents and the recent advances and emerging future in cancer therapy.