Blood group antigen A type 3 expression is a favorable prognostic factor in advanced NSCLC

Schmidt LH, Kuemmel A, Schliemann C, Schulze A, Humberg J, Mohr M, Görlich D, Hartmann W, Bröckling S, Marra A, Hillejan L, Goletz S, Karsten U, Berdel WE, Spieker T, Wiewrodt R

Abstract

Objectives: Several blood group-related carbohydrate antigens are prognosis-relevant markers of tumortissues. A type 3 (repetitive A) is a blood group antigen specific for A1erythrocytes. Its potential expressionin tumor tissues has so far not been examined.Material and methods: We have evaluated its expression in normal lung and in lung cancer using a novelantibody (A69-A/E8). For comparison an anti-A antibody specific to A types 1 and 2 was used, becauseits expression on lung cancer tissue has been previously reported to be of prognostic relevance. Resectedtissue samples of 398 NSCLC patients were analyzed in immunohistochemistry using tissue microarrays.Results and conclusions: Expression of A type 3 was not observed in non-malignant lung tissues. A type3 was expressed on tumor cells of around half of NSCLC patients of blood group A1(p < 0.001). Whereasno prognostic effect for A type 1/2 antigen was observed (p = 0.562), the expression of A type 3 by tumorcells indicated a highly significant favorable prognosis among advanced NSCLC patients (p = 0.011) andin NSCLC patients with lymphatic spread (p = 0.014). Univariate prognostic results were confirmed in aCox proportional hazards model. In this study we present for the first time prognostic data for A type3 antigen expression in lung cancer patients. Prospective studies should be performed to confirm theprognostic value of A type 3 expression for an improved risk stratification in NSCLC patients.