Washington: Scientist have revealed that a protein called isocitrate dehydrogenase (IDH1) is available at high levels in lung cancers and can be detected in the blood, making it a noninvasive diagnostic marker for lung cancers.
Jie He , M.D., Ph.D., director of the Laboratory of Thoracic Surgery at the Peking Union Medical College and Chinese Academy of Medical Sciences in Beijing said that they have identified IDH1 as an effective plasma biomarker with high sensitivity and specificity in the diagnosis of NSCLC, especially lung adenocarcinoma.
He and colleagues found that IDH1 could be detected in the blood of lung cancer patients with 76 percent sensitivity and 77 percent specificity.
When they used a mathematical model to combine the detection of IDH1 with the detection of existing markers CEA, Cyfra21-1, and CA125, the sensitivity increased to 86 percent.
He and colleagues used blood samples collected from 943 patients with NSCLC and 479 healthy controls, enrolled between 2007 and 2011 in the Cancer Institute and Hospital of the Chinese Academy of Medical Sciences.
Using methods called ELISA and ECL, they measured the levels of IDH1, CEA, Cyfra21-1, and CA125 in the participants' blood.
The researchers then divided the samples into a training set and a test set to validate the detection efficiency of IDH1. They found the data obtained from the test set were as good as those from the training set, demonstrating the robustness of IDH1 as a biomarker for lung cancer diagnosis.
The median IDH1 levels in patients with two types of lung cancer, adenocarcinoma and squamous cell carcinoma, were 2.7-fold and 2.2-fold higher, respectively, compared with healthy controls.
The study has been published in Clinical Cancer Research.