CST3 and squamous cell lung carcinoma: Lung squamous cell carcinoma has a clear causal relationship with creatinine (β: 0.021, P: 1.16×10-5, FDR: 1.05×10-3*), Cystatin C (β: 0.028, P: 0.004, FDR: 0.036*), potential positive causal relationships with urate (β: 0.012, P: 0.020, FDR: 0.180), urea (β: 0.010, P: 0.046, FDR: 0.141), and Glycated Haemoglobin HbA1c (β: 0.019, P: 0.049, FDR: 0.098), and a clear negative causal relationship with eGFR (β: -0.022, P: 9.58×10-6*, FDR: 8.62×10-5*), and a potential negative causal relationship with SHBG (β: -0.020, P: 0.036, FDR: 0.108).