| Gastric cancer is the most commonly-observed malignance in Asian and Pacific regions, positioning the 3rd place among cancer killers. The fact that most gastric cancer patients are asymptomatic, plus the insufficient sensitivities of the current diagnostic techniques like gastroscopy and pathology, gives a hard time for an early diagnosis of gastric cancer. The biomarker is one of the possible ways out from the situation, but the both sensitive and specific gastric cancer biomarker is still waiting to be discovered. With its superior stomach specificity, gastric fluid proteome might become a gold mine for ready-to-use early diagnostic gastric cancer biomarkers in the future.OBJECTIVE: To find out the affection upon electrophoresis band patterns by the physiological and chemical properties like initial acidity and color of the gastric fluid, and the possible connection between the affection and gastric cancer, so as to lay a foundation for future gastric biomarker mining using MS and LC, etc..METHODS: 1. to collect and process the gastric fluid samples, and analyze their information; 2. to find out the underlining relations between the initial pH value and gastric cancer, and the possible factors functioning in pH alteration.RESULTS & DISCUSSION: 1. the structure of gender and age of the collected gastric cancer samples is in accordance with the reported data; 2. the anatomic location of carcinogenesis might have some effect on the initial pH value of the sample; 3. electrophoresis band patterns are affected by initial pH values: pH1~2 samples display fewer bands and are better resolved when compared to pH≥6 samples. The probable cause is that the generation and activity of pepsin are suppressed under neutral or alkalic environment, which consequently leads to a preservation of some proteins with low abundances. The genetic changes of the cancer cells or cells with precancerous lesions might bring some differences to the composition of the gastric fluid proteome. |
