To further explore the differential protein intensity in cancer progression and invasion, we analyzed the metastatic and nonmetastatic groups, focusing on the above trend proteins, and found that EMILIN2 is a critical protein in LCNEC, while NUDT3 and NME4 are key players in cSCLC-LCNEC. Here, NME4 is linked to large cell neuroendocrine carcinoma.