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Introduction

B4GALT7 is one of seven beta-1,4-galactosyltransferase (beta4GalT) genes, which encode type II membrane-bound glycoproteins that appear to have exclusive specificity for the donor substrate UDP-galactose. According to previous studies aberrant B4GALT7 expression has distinct functions in different tumors. Here, we evaluate the association of B4GALT7 expression with oncologic outcomes in patients with localized clear cell renal cell carcinoma (ccRCC) managed by surgery.

Methods

A retrospective analysis of 207 and 231 patients with localized ccRCC undergoing RN or NSS at two academic medical centers respectively between 2005 and 2009 was performed. The first cohort with 207 patients was treated as training set and the other as validation set. Tissue microarrays (TMAs) were created in triplicate from formalin-fixed, paraffin embedded specimens. Immunohistochemistry with a commercially available monoclonal B4GALT7 antibody was performed with the intensity (0 to 3) and percentage (0 of 100) of staining recorded. The association of B4GALT7 expression with standard pathologic features and prognosis were evaluated.

Results

B4GALT7 expression was significantly associated with tumor T stage (P<0.001 and P<0.001, respectively), Fuhrman grade (P<0.001 and P<0.001, respectively) and necrosis (P=0.021 and P=0.002, respectively) in both training and validation sets. Moreover, high B4GALT7 expression indicated poor overall survival (OS) (P<0.001 and P<0.001, respectively) in the two sets. The incorporation of B4GALT7 into T stage and Fuhrman grade would help to refine individual risk stratification. Furthermore, B4GALT7 expression was identified as an independent adverse prognostic factor for survival.

Conclusions

Increased B4GALT7 expression is a potential independent adverse prognostic factor for overall survival in patients with localized ccRCC. Inhibiting B4GALT7 pathway might be a promising target of postoperative adjuvant therapy for these ccRCC patients.

Funding

none