Osteopontin expression correlates with prognostic variables and survival in clear cell renal cell carcinoma

✍ Scribed by Koviljka Matusan; Gordana Dordevic; Darko Stipic; Vladimir Mozetic; Ksenija Lucin

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 289 KB
• Volume: 94
• Category: Article
• ISSN: 0022-4790
• DOI: 10.1002/jso.20447

✦ Synopsis

Abstract

Background and Objectives

Osteopontin (OPN) is a phosphorylated glycoprotein with diverse functions including tumorigenesis and tumor cell metastasis. Recently, it has been detected in a growing number of human tumors, and assessed as a potential prognostic marker. The aim of this study was to analyze the expression of OPN in normal renal tissue and clear cell renal cell carcinomas (CRCCs), and to assess its prognostic significance.

Methods

The expression of OPN protein was immunohistochemically analyzed in 171 CRCCs and compared to usual clinicopathological parameters such as tumor size, nuclear grade, pathological stage, Ki‐67 proliferation index, and cancer‐specific survival.

Results

In normal renal parenchyma, the expression of OPN was seen in distal tubular epithelial cells, calcifications, and some stromal cells. The upregulation of OPN was observed in 61 CRCCs (35.7%) in the form of cytoplasmic granular staining of various intensities. Statistical analysis showed correlation of the OPN expression with tumor size (P < 0.001), Fuhrman nuclear grade (P < 0.001), pathological stage (P = 0.011), and Ki‐67 proliferation index (P < 0.001). Moreover, patients with OPN‐positive tumors had significantly worse prognosis in comparison to patients with tumors lacking OPN protein (P = 0.004).

Conclusion

Our results suggest that overexpression of OPN is involved in the progression of CRCC. J. Surg. Oncol. 2006;94:325–331. © 2006 Wiley‐Liss, Inc.