Clinical Significance Of Collagen Type â…£ And HA In Gastric Juice And Serum In Diagnosis Of Gastric Carcinoma And Precancerous Lesion And The Correlation With The Expression Of Cath-D

Background Invasion and metastasis are important biocharacteristics of tumor.When tumor cells invade surrounding tissues, they have to break through a serial of biologic barriers. Extracellular matrix(ECM) is the physiologic barrier which have to be broken through in the invasion and metastasis of tumor. Collagen typeâ…£and hyaluronic acid(HA) are the major components of basement membrane(BM) and ECM respectively. Cathepsin D(Cath-D) is an aspartyl lysosomal protease involved in the degradation of the basement membrane and extracellular matrix. However,there is no report about the levels of collagen typeâ…£and HA in gastric juice in gastric cancer and precancerous lesion,and also there is no study concerning the correlation of the levels in gastric juice and serum. The research data on the degrading effect of Cath-D on ECM in the gastric cancer tissue is scarce.Aims The aim of this study was to investigate the clinical significance of collagen typeâ…£and HA in gastric juice and serum for an aid in diagnosis of gastric cancer and precancerous lesion, and the possible degrading effect of cathepsin D on collagen typeâ…£and HA.Methods Fifty gastric cancer patients were enrolled in our study compared with 41 patients with precancerous lesion, 20 patients with gastric ulcer and 30 patients with superficial gastritis. Clinical history was recorded, and the gastric juice, serum and gastric tissue were collected.The pH value of gastric juice is determined by exact pH paper.Collagen typeâ…£and HA in gastric juice and serum were analyzed by radioimmunoassay. Expression of cathepsin D and collagen typeâ…£in gastric tissue were tested by immunohistochemical staining with monoclonal antibodies.Results The pH value of the gastric juice was significantly higher in patients with gastric cancer than that in the patients with precancerous lesion and superficial gastritis (P < 0.01).The contents of collagen typeâ…£and HA in gastric juice were significantly higher in the patients with gastric cancer than those in the patients with precancerous lesion (P < 0.05). And also the concentrations of collagen typeâ…£and HA in gastric juice were significantly higher in the patients with gastric cancer than those in the patients with superficial gastritis (P < 0.01).Serum collagen typeâ…£level was increased in the patients with gastric cancer compared with the patients with precancerous lesion(P < 0.05). The level of serum HA was significantly higher in the patients with gastric cancer than that in the patients with precancerous lesion and superficial gastritis (P < 0.05,P<0.01 ,respectively).The levels of collagen typeâ…£in gastric juice in gastric cancer group, precancerous lesion group and superficial gastritis group were significantly lower than those in serum(P < 0.01). The HA levels in gastric juice in the three groups were respectively higher than those in serum(P < 0.01). The levels of collagen typeâ…£and HA in gastric juice were significantly higher in patients with ulcerated gastric cancer than those in patients with gastric ulcer and superficial gastritis( P < 0.05,P < 0.01,respectively). The HA level in gastric juice was significantly higher in patients with gastric ulcer than that in patients with superficial gastritis(P < 0.05). The content of serum HA was also significantly increased in patients with ulcerated gastric cancer compared with the patients with gastric ulcer and superficial gastritis (P < 0.05,P < 0.01, respectively). Gastric cancer patients with lymph node metastasis had higher levels of collagen typeâ…£and HA in gastric juice than those in the patients without metastasis(P < 0.05). There were significant correlations between concentrations of HA and collagen typeâ…£in the gastric juice and serum (rs = 0.498, 0.323,P < 0.01). The sensitivity of conbined detection of HA and collagen typeâ…£in diagnosis of gastric cancer was higher than that of separate detection of HA and collagen typeâ…£(P < 0.05).The expression of cathepsin D was significantly increased in patients with gastric cancer compared with superficial gastritis (P < 0.01). The expression of cathepsin D was significantly increased in patients with precancerous lesion compared with superficial gastritis(P < 0.01).The continuous expression of collagen typeâ…£in basement membrane in gastric cancer group was lower than that in precancerous lesion group and superficial gastritis group(P < 0.01). In the gastric cancer group, the positive expression of cathepsin D showed a significant negative correlation with the continuity of collagen type IV (r = -0.33,P = 0.015).Conclusions The analysis of collagen typeâ…£and HA in gastric juice and serum may provide a simple aid in diagnosing gastric cancer and evaluating whether metastasis is occurring or not. There is a clinical significance of detecting the levels of HA and collagen typeâ…£in gastric juice and serum in differential diagnosis of benign and malignant ulcer. The sensitivity of conbined detection of HA and collagen typeâ…£in diagnosis of gastric cancer was higher compared with separate detection of HA and collagen typeâ…£. The expression of cath-D in gastric cancer tissue is high, and it is possible involving in the degradation of BM and ECM.