MMP7 and lung cancer: Further subgroup analysis based on MMP-7 detection methods revealed that MMP-7 protein expression in lung cancer patients with TNM stage III-IV expressed higher than the patients with TNM stage I-II by using SP (OR = 2.52, 95% CI: 1.57 to 4.03, P <0.001), while the difference of MMP-7 protein expression between lung cancer patients with TNM stage III-IV and patients with TNM stage I-II showed no statistical significance by using Non-SP (P = 0.519), as shown in Figure 3.