Antisense strategy in hematological malignancies

Standard cytotoxic chemotherapy for neoplastic disease is fraught with systemic toxicity. The ratio of the toxic dose to the therapeutic dose is relatively low, which reflects the large number of cellular targets affected by the chemotherapeutic agent as well as its inability to distinguish between normal and malignant cells. The discovery of oncogenes and tumor suppressor genes involved in the process of transformation of normal cells into malignant cells has opened new areas of research in oncology, aimed at discovering drugs that could selectively inhibit their biological effects. This therapeutic modality, called an antisense strategy, has become a powerful tool for selectively reducing the expression of target genes in vitro, and there is increasing interest in the possibility of using the same technology in vivo for therapeutic purposes. In oncohematology, a number of trials have been initiated with antisense oligonucleotides directed against molecular targets, including the bcl-2, c-myc, bcr-abl, c-myb or p53 oncogenes and tumor suppressor genes. The experience gained from these studies will be applicable to the next generation of antisense compounds, which may include oligonucleotides with novel backbones or other structural modifications, as well as for expansion of the use of antisense oligonucleotides in combination approaches for the treatment of hematological malignancies.