New perspectives for cancer chemotherapy by genetic protection of haematopoietic cells

The effectiveness of anti-cancer chemotherapy can be limited by acute suppression of the bone marrow (myelosuppression). There is also a risk of therapy-related secondary haematopoietic malignancy as well as acute and longer term effects in other tissues. Clinical strategies have been established to address some of these problems, particularly toxic effects on the bone marrow (acute myelotoxicity); however, there is still substantial scope for improving the management of chronic toxicity and mutagenicity to haematopoietic cells and collateral damage to non-haematopoietic cells during chemotherapy. In this review, we have discussed a novel strategy that involves the transfer and expression of drug-resistance functions into haematopoietic stem cells and more-mature blood progenitor cells, to overcome both the acute and long-term deleterious effects of anti-tumour treatment in bone marrow. The potential advantages of this approach include: (1) the in vivo selection of protected cell populations, which offers the possibility of intensification or escalation of chemotherapeutic drug doses; (2) a reduction in the frequency of therapy-related leukaemia and (3) tumour sensitisation to chemotherapy at the same time as haematopoietic protection.