CD19 and gastric cancer: In summary, we identified that certain abnormal proportions of miRNAs (hsa-miR-1306-5p, hsa-miR-3173-5p, hsa-miR-296-5p) and lymphocyte subsets (the absolute numbers of CD3+ T cells, CD4+ T cells, CD8+ T cells, CD19+ B cells, total lymphocytes) are strongly associated with the diagnosis and prognosis of GC, making them potential biomarkers for this disease.