Die Expression von MAGE Tumor assoziierten Antigenen in gut differenzierten, nicht kleinzelligen Lungenkarzinomen korreliert mit geringerem Überleben

Abstract

Introduction: MAGE tumor associated antigens (TAA) belong to the so called cancer/testis TAA family characterized by expression in different types of cancer including non-small cell lung cancer (NSCLC). Recently developed tissue microarray technology (TMA) allows rapid visualization of molecular targets in hundreds of tissue samples at the DNA, RNA or protein level. We have studied the expression of MAGE proteins in a lung cancer tumor array and analyzed the correlation of TAA expression with histological and survival data. Materials and Methods: The expression of MAGE-A4 protein was evaluated with immunohistochemistry by using a monoclonal antibody, 57B [1], in a NSCLC tissue microarray. Clinical data were obtained from clinical and pathology records. Chi square tests and Kaplan-Meier plots were used for statistical analysis. Results: 57B staining was observed in 130 out of 301 (43.2%) NSCLC biopsies. With regards to histological classification, 97 out of 178 (55.1%) squamous cell and 12 out of 65 (18.4%) adenocarcinomas were 57B positive. MAGE-A4 protein was expressed in 19 out of 76 (25%) highly/moderately differentiated and in 110 out of 223 (49.3%) poorly differentiated carcinomas. The 5 years overall survival of patients bearing squamous cell carcinomas was 70% for 57B negative tumors vs. 45% (p = 0.027) for 57B positive tumors. For patients suffering a 57B positive highly/moderately differentiated squamous cell carcinoma 5 year overall survival was 42% vs. 80% for 57B negative tumors (p = 0.046). Conclusions: Correlation with poor survival suggests that MAGE-A4 expression represents a prognostic indicator in NSCLC.