NT5E and gastric cancer: Overexpression of CD73 promotes the malignant properties of cancers, such as proliferation, invasion, migration, adhesion, and metastasis, and it is associated with specific clinical characteristics and worse prognosis in many types of human cancers, including melanoma, leukemia, pancreatic cancer, triple-negative breast cancer, thyroid cancer, gastric cancer, prostate cancer, colon cancer, and ovarian cancer [26,27,28,29,30,31,32,33,34,35].