May 28, 2005

Blood Breakthrough Might Improve Cancer Care

Safe method of increasing tissues' oxygen supply may bring many benefits

Boosting the supply of oxygen to tissues in need could help improve wound healing, lead to better blood substitutes, and even help with cancer treatments. Now a team of Duke University researchers believe they've found a safe way of doing just that.

Adding the compound nitric oxide to the blood's hemoglobin -- the component of blood that carries oxygen to cells -- can help hemoglobin deliver more oxygen to tissues without increasing heart rate or constricting blood vessels, the researchers say.

The study appears in the May 27 issue of the journal Circulation Research.

"Hemoglobin needs its natural partner in the blood, nitric oxide, to do its job of delivering oxygen to tissues, but current treatments deliver hemoglobin without nitric oxide," study leader Mark Dewhirst, professor of radiation oncology, said in a prepared statement.

"Hemoglobin by itself actually reduces oxygenation to tissue because it constricts blood vessels, reducing blood flow," Dewhirst explained.

That means when hemoglobin is delivered alone, it may cause potentially fatal side effects, reducing the effectiveness of radiation treatment and chemotherapy.

But tumors are often low in oxygen, which makes them more resistant to chemotherapy or radiation treatment, the researchers noted. A method that used hemoglobin to safely deliver oxygen to tumor tissues might improve treatment

In their studies with animals, the Duke team found that pure oxygen, breathed in naturally, increased the level of circulating oxygen but not oxygen levels in arteries feeding tumors. In contrast, hemoglobin containing nitric oxide raised oxygen levels in tumors.

More information

Duke University

The U.S. National Library of Medicine has more about hemoglobin.