2008 Volume 9 Issue 1 Pages 13-19
Hypoxia is a hallmark of malignant tumors. Although more than half a century has passed since it was suggested that tumor hypoxia caused bad treatment outcomes and contributed to the recurrence of tumors, no fundamental solution to this problem has been found yet. Since the hypoxia-inducible transcription factor HIF-1 was reported in 1992, research on hypoxic tumor cells has progressed with increasing speed, and it was found that the function of various genes, the expression of which is induced in hypoxic tumor cells by HIF-1, is strongly associated with the malignant alteration of the whole tumor. Therefore, HIF-1-active hypoxic cells in solid tumors are extremely important therapeutic targets of cancer therapy, particularly in the therapy of refractory cancers. Furthermore, HIF-1-active cells are considered crucial to obtain information on the hypoxic fraction of solid tumors, and to conduct therapies that act specifically at these cells for achieving a greater anticancer effect and preventing the recurrence and malignant alteration of cancers. We have been developing PTD-ODD fusion proteins, which are specific to HIF-1-active tumor cells, to target and image them for treating and diagnosing the malignant tumors, respectively.
