4D label-free quantitative proteomics of primary treatment-naive small cell lung cancer (SCLC) tumors and paired normal adjacent tissues

Proteomic analysis was performed on 12 pairs of treatment-naive primary small cell lung cancer (SCLC) tumors and matched normal adjacent tissues (NATs) using 4D label-free quantitative HPLC-MS/MS. Briefly, proteins were extracted from frozen tissue samples, digested into peptides, and analyzed on a Q Exactive HF-X mass spectrometer coupled with an EASY-nLC 1200 system. Raw data were searched against the UniProt Human database using MaxQuant (v2.2.1.0), and differential proteins were identified using Perseus software with thresholds of |log2FC| > 1 and P < 0.05.