Amidst initiatives for medical research of cancer, researchers are striving to improve a new generation of anticancer drugs for specifically targeting low-oxygen environment of solid tumors. Until now, in preliminary experiments, the new drug has been tested for human tumors transplanted into healthy adult mice.
For clinical purposes, low oxygen levels among tightly packed cells of solid tumors serves as a convenient indicator to distinguish them from healthy cells. In such a structure, the low-oxygen environments are aimed to be directly targeted to avoid the side effects of radiation treatments and chemotherapy, explain researchers.
In a bid for this, a team of researchers at the Research Center for Advanced Science and Technology has developed a new drug known as oligomerized nucleosides. Structurally, the new drug has a short chain of molecules that is of the shape of genetic material DNA and RNA. The nucleosides used in the manufacture of drug contain floxuridine residues, which, currently are used in the manufacture of some standard chemotherapy drugs.
“During clinical trials, when the new drug was added to lung tumor cells in humans, it showed anticancer activity albeit under low-oxygen concentration conditions. And, by simple intravenous injection, the drug effectively defeated the growth of solid tumors,” stated the lead researcher.
In fact, the new short-chain floxuridine oligomers act only in low oxygen areas. This is because they are encircled by protective molecules that work as oxygen-responsive packaging. On the other hand, for healthy cells, the protective packaging remains intact with no effect of the drug. Meanwhile, for cells with low oxygen levels, the drug degrades the packaging, frees the floxuridine oligomers to initiate enzymatic reactions for the cell to die.