However, the levels of secreted TFF3 proteins in the serum of lung cancer patients (squamous cell lung carcinoma, 592.2±110.2; adenocarcinoma, 665.8±118.6; SCLC, 983.4±229.5) are significantly higher when compared with the levels in healthy individuals (230.7±46.9). Here, TFF3 is linked to small cell lung carcinoma.