CD44 and gastric cancer: Obviously, P53 (n = 39), CD44 (n = 35), androgen receptor (n = 31), srsf3 (n = 24), and esrp1 (n = 16) were several molecular keywords with the highest frequency; apoptosis (n = 94), EMT (n = 61), metastasis (n = 55), angiogenesis (n = 40), proliferation (n = 34), and epigenetics (n = 23) were several pathological process keywords with the highest frequency; and breast cancer (n = 115), colorectal cancer (n = 82), prostate cancer (n = 76), hepatocellular carcinoma (n = 76), and gastric cancer (n = 41) were several disease keywords with the highest frequency in AS of cancer studies.