Blood protein might indicate early-stage lung cancer
Researchers have identified a protein in blood taken from lung cancer patients that appears to be absent in blood from people who do not have the disease.
The protein, human aspartyl (asparaginyl) beta-hydroxylase (HAAH), is usually found inside healthy cells. But in cancer cells, the protein is found on the cells' outer surface and, as a result, gets into the person's bloodstream.
Researchers at Panacea Pharmaceuticals in Maryland, US, suggest that HAAH appears on the cell surface during the early stages of lung cancer.
This could mean that detecting the protein in the blood may enable early diagnosis of the disease, even before symptoms become apparent.
"A positive test for this protein marker, followed by CT scanning, may help identify individuals with lung cancer at a stage in which treatment is more effective, possibly even curative," said research scientist Mark Semenuk, who presented the team's findings at the American Association for Cancer Research's second International Conference on Molecular Diagnostics in Cancer Therapeutic Development in Atlanta, Georgia.
The researchers carried out tests on 160 patients with various stages and types of lung cancer and found that 99 per cent had high levels of HAAH in their blood compared to just nine per cent of 93 non-smokers who appeared to be free from cancer.
Dr Semenuk commented: "These results are very encouraging, because it points to those patients who are most likely to need further testing.
"Elevated levels of HAAH cannot confirm whether a person has lung cancer, but can be used as a routine screening test for recommending further diagnostic evaluation." he claimed.
The researchers noted that HAAH may also provide a screening target for other types of cancer, as the protein was found to be expressed in a wide range of cancers.
Dr Kat Arney, senior science information officer at Cancer Research UK, said: "As well as encouraging people to quit smoking to prevent lung cancer in the future, we urgently need to find ways to diagnose the disease earlier."
She added: "Although larger studies will show if HAAH is suitable as a screening test for lung cancer, these early results are certainly interesting."