In a new study entitled “AKAP4 is a circulating biomarker for non-small cell lung cancer,” researchers at The Wistar Institute discovered the protein AKAP4 as a potential new biomarker for non-small cell lung cancer that can be easily detected in patients’ blood. The study was published in the journal Oncotarget.
Lung cancer is a leading cause of death in both men and women cancer patients in the United States. However, if the disease is diagnosed in its early stages and patients receive prompt treatment, their five-year survival rate significantly increases.
In this study, researchers at The Wistar Institute set out to discover new biomarkers for lung cancer that would improve diagnostics at early stages. They focused on cancer testis antigens (CTAs), a large family of tumor-associated antigens expressed in different types of human tumors but not in normal tissue. More importantly, CTAs are also widely expressed in circulating tumor cells (CTCs), cells that have travelled from the primary tumor into the bloodstream.
To test if tumor derived CTA mRNAs could be detected from blood samples, the team analyzed the expression of 116 CTAs from the blood of non-small cell lung cancer (NSCLC) patients. They found one protein, AKAP4, as a potential NSCLC biomarker, which would allow distinguishing between patients with and without NSCLC. To validate the role of AKAP4 as a biomarker, researchers analyzed a larger set of new samples, specifically 264 blood samples from patients with NSCLC and 135 from healthy controls. From the 264 NSCLC blood samples, 136 of patients were diagnosed with stage I NSCLC. The effectiveness of AKAP4 as a biomarker was analyzed by a method that calculates if the molecule in question can distinguish between positive and negative carriers of disease. The test result is a number where a value of 1 indicates a perfect distinction between patients who have a particular disease or not. In this case, when the team compared the 264 NSCLC samples with the 135 control samples, they obtained a value of 0.9714. When analyzing solely the 136 samples of patients’ diagnosed with stage I, the test value was 0.9795.
As Qihong Huang, M.D., Ph.D., associate professor in the Tumor Microenvironment and Metastasis Program at The Wistar Institute and study lead author noted, “The results of this study exceeded our expectations. AKAP4 appears to be a highly effective biomarker for the detection of non-small cell lung cancer. If we are able to confirm these results in a more robust study, then we have the potential for a new, more accurate screening method that could help save many, many lives.”
The team now plans to conduct a larger study and analyze at least 800 samples retrieved from different hospitals to further validate their findings.
Dario C. Altieri, M.D., President and CEO of The Wistar Institute and director of Wistar’s Cancer Center commented, “Qihong and his colleagues have found a target that could result in a more accurate test than any method that’s been used to screen for non-small cell lung cancer to date. With the government recommending annual screening for high-risk populations, the identification of a promising target like AKAP4 comes at a critical time. Early detection is needed in order to have a meaningful impact on this devastating disease.”