Finally, five genes were found to be pivotal genes in the pathogenesis of GC and COVID-19 pneumonia: BGN (biglycan), UBE2C (ubiquitin-conjugating enzymes 2C), SPP1 (secreted phosphoprotein 1), THBS2 (thrombospondin 2), and COL1A1 (type I collagen alpha 1). Here, SPP1 is linked to gastric cancer.