Signal Transduction Proteins in Tumors From Puerto Rican and Caucasian Gastric Adenocarcinoma Patients: Expression Differences With Potential for Specific Targeted Therapies

Abstract

Gastric cancer is the second cause of cancer death with approximately 800,000 annual new cases reported worldwide. The incidence of gastric adenocarcinoma has progressively increased, while 5-year survival rates of 20% have remained unchanged for several decades. New strategies for early detection and treatment remain a significant unmet medical need. Advances in our understanding of signal transduction mechanisms have led to novel treatment approaches in a variety of tumors. Over-expression of the HER2/NEU gene is associated with aggressive behavior and poor prognosis in breast cancer, and this has made the Her2/neu protein a target for directed therapy. Several reports indicate that there are ethnic differences in the clinical behavior of gastric cancer, but the reasons for this observation are not clearly understood. We have investigated potential differences in the expression of selected signal transduction proteins (Her2/neu, EGF-R, Cyclin D1 and p-Stat3) in gastric cancers from 100 Puerto Rican and 95 Caucasian patients. Puerto Rican patients had higher disease stages at presentation (Stage IV disease was observed in 44% of Puerto Ricans and in 18% of Caucasians). The majority of tumors in both populations showed over-expression of p-Stat3 but there were no statistical significant differences between the two groups. Her2/neu was over-expressed in the tumors of both patient populations but at higher HHS Public Access

Association between Helicobacter pylori infection, mismatch repair, HER2 and tumor-infiltrating lymphocytes in gastric cancer

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