Researchers measured the blood level of the peptide thymosin‑alpha‑1 in people with lung cancer and found that, on average, it was higher than in healthy folks, but half the patients had normal levels. The amount didn’t track with tumor stage, didn’t fall after the tumor was removed, and higher levels were linked to worse survival, especially if the person also had another cancer. So the peptide might serve as a warning sign rather than a treatment tool.

Prothymosin-alpha, the precursor of thymosin-alpha1, may play a role in cell proliferation, and the plasma level of thymosin-alpha1 may reflect the degree of proliferation of the tumor cells. Recently, a new sandwich immunoradiometric assay for thymosin-alpha1 was developed using monoclonal and polyclonal antibodies. In this investigation, we used this assay to measure plasma and tissue level of thymosin-alpha1 in 131 lung cancer patients. We found that the mean plasma thymosin-alpha1 levels in lung cancer patients were higher than in normal individuals (P < 0.001). However, half of the patients showed normal levels. Thymosin-alpha1 levels correlated neither with the stage nor pathological subtype of the lung cancer, and did not decrease significantly in the 4 weeks after the resection of the tumor. Thymosin-alpha1 levels of lung cancer patients with another cancer were higher than those without evidence of other cancers (P = 0.03). Survival of patients with normal levels of plasma thymosin-alpha1 was significantly better than that with higher levels (P = 0.04). The plasma level of thymosin-alpha1 may be used as a marker for the prognosis of lung cancer patients. Further investigations are warranted to determine its role in the lung cancer.