And co‐analysed COL3A1 and 184 KEGG pathways, heatmap plot (Figure 5B) showed the top four KEGG pathways were ECM receptor interaction (R = 0.21, P < 0.001), N‐glycan biosynthesis (R = 0.19, P < 0.001), small cell lung cancer (R = 0.18, P < 0.001) and glycosaminoglycan degradation (R = 0.18, P < 0.001). Here, COL3A1 is linked to small cell lung carcinoma.