Functional Analysis And Molecular Mechanisms Of Osteopontin In The Progression Of Human Gastric Carcinoma Cells

Osteopontin (OPN) is a secreted, adhesive and calcium-binding phosphoprotein. Previous research found that OPN was involved in physiological and pathological processes in variety of tissues and organs through bindinging with integrins and CD₄₄ receptors. Recently, OPN has also been found that it is a multifunctional matrix protein, and it has been detected in a number of human tumor types, including breast, prostate, liver, colon, oesophageal, glioma and lung cancer. It has been found that OPN protein and mRNA were elevated in malignant vs benign/normal tissues. Several reports indicated that OPN is involved in the processes of tumor cell survival, migration, invasion and angiogenesis. Gastric cancer is very frequent in China and often in advanced stage at first presentation. Unusual expression of many genes including tumor-suppressor genes, oncogenes and tumor metastasis-associated genes were involved in the progression of gastric cancer. Recent studies showed that OPN mRNA was elevated in gastric cancer vs normal tissues. However, the function and the regulation mechanisms of OPN in the progression of gastric cancer were incompletely understood.Here, the expression of OPN, MMP9, HIF-1αand CD34 were detected in non-cancer gastric tissues and gastric cancer tissues by immunohistochemistry analysis. OPN, MMP9 and HIF-1αcould not been deteced in the non-cancer gastric tissues samples. MVD was elevated in human gastric cancer tissues vs normal tissues, and the MVD was higher in the gastric cancer tissues which OPN, MMP9 and HIF-1αoverexpressed. There was statistically significant differences in the expression of OPN, MMP9 and HIF-1αbetween the samples of with and none lymph nodes metastasis or between the high and low differentiation (p<0.05). Correlations existed between OPN and MMP9, and between OPN and HIF-1α(r=0.872, p<0.01 and r=0.878, p<0.01). These data implies that OPN, MMP9 and HIF-1αwere interrelated during the progression of gastric cancer.To understand the function and molecular mechanisms OPN in the gastric...