HMGB1 and gastric cancer: HMGB1 overexpression and or elevated serum HMGB1 levels have been observed in several types of cancer, including nasopharyngeal carcinoma, liver cancer, prostate cancer, pancreatic cancer, melanoma, gastric cancer, esophageal cancer, cervical cancer, breast cancer, malignant pleural mesothelioma, and bladder cancer (15).