CASP4 and lung carcinoma: We found that the circulating caspase-4 was three-fold increased (95% CI, 1.331–1.94 ng/ml) compared to healthy subjects (95% CI, 0.3947–0.6197 ng/ml), although at lower levels than in lung cancer patients (95% CI, 2.603–3.372 ng/ml) (Figure 3A).