MCAM and digestive system cancer: The significant correlation was also spotted between CD146 overexpression and poor OS in patients with lung cancer (OS: pooled HR = 2.172, 95% CI = 1.453–3.246, P < 0.001) and digestive system cancer (pooled HR = 2.661, 95% CI = 2.149–3.295, P < 0.001).