Contributed by William Angelos| 14 March, 2005  21:12 GMT
 Because ON01910 is highly effective in combination with other chemotherapies and appears to be nontoxic, it may be beneficial for treatment of some advanced cancers that are resistant to conventional therapies.
A newly developed drug known as "ON01910" has been found to inhibit the development of polo-like kinase1 (Plk1), a molecule that plays a key role in the formation of many cancerous tumors, according to research published in the March issue of the journal
Cancer Cell.
The compound is a potent inhibitor of human tumors in a mouse model system, has low toxicity, and could lead to a new avenue for targeted cancer therapy, the researchers say.
The results of their study have led to clinical evaluation of ON01910 in phase I clinical trials.
Stops Cell Division in 'Notoriously Resistant' Cancers
The Plk1 molecule plays an important role in cell division. High levels of Plk1 have been observed in many human tumors, and studies using various laboratory techniques have shown that inhibition of Plk1 activity leads to cell death.
"Because all signaling pathways that have gone awry in a cancer cell ultimately affect cell proliferation, a reasonable approach to cancer therapy is to develop inhibitors that block the function of a critical molecule that is required by a tumor cell to complete cell division," explains lead author Dr. E. Premkumar Reddy from Temple University School of Medicine. "One such molecule appears to be Plk1."
Dr. Reddy and colleagues examined the effects of Plk1 inhibitor ON01910 on tumor growth in several animal models. The researchers found that ON01910 arrests cell division in a variety of human cancer cells, including cells that are notoriously resistant to commonly used chemotherapeutic agents.
May Be Effective in Treating Liver, Breast, Pancreatic Cancers
The compound significantly inhibited a wide variety of human tumors, including liver, breast and pancreatic cancers that were grown in mice. ON01910 also was highly effective -- and, in many cases, strongly synergistic -- when tested in combination with other chemotherapeutic agents.
Studies examining normal human cells show that they are not influenced by ON01910.
The authors suggest that because ON01910 is highly effective in combination with other chemotherapies and appears to be nontoxic, it may be beneficial for treatment of some advanced cancers that are resistant to conventional therapies.
"Clinical studies, which are currently in progress, should reveal the best way to utilize ON01910 in human cancer therapy," writes Dr. Reddy. |