Regulation of prostate cell collagen receptors by malignant transformation

✍ Scribed by Tuomas Mirtti; Camilla Nylund; Janika Lehtonen; Heikki Hiekkanen; Liisa Nissinen; Markku Kallajoki; Kalle Alanen; Donald Gullberg; Jyrki Heino

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: French
• Weight: 430 KB
• Volume: 118
• Category: Article
• ISSN: 0020-7136
• DOI: 10.1002/ijc.21430

✦ Synopsis

Abstract

Cell adhesion receptors, including the integrin‐type collagen receptors (α~1~β~1~, α~2~β~1~, α~10~β~1~ and α~11~β~1~) participate in cancer progression and invasion. Quantitative RT‐PCR indicated that all 4 receptors are abundantly expressed in sarcoma‐derived cell lines, whereas most carcinoma‐derived cells express α~1~β~1~ and α~2~β~1~ only. This was surprising because α~11~β~1~ has been connected previously to the progression of lung adenocarcinomas. To test the hypothesis that α~11~ expression may not persist in cultured cancer cells we analyzed fresh tissue samples of 104 total prostatectomies, keeping in mind that prostate cancer cell lines showed negligible α~11~ mRNA levels. In prostate α~2~ expression was significantly lower in poorly differentiated carcinomas when compared to benign lesions (p = 0.0331). In immunohistochemistry the protein levels of α~2~ integrin decreased significantly (p = 0.0001) and the protein levels of α~11~ subunit increased significantly (p = 0.029) with the increasing grade of carcinoma. Thus α~11~β~1~ may replace α~2~β~1~ during tumor progression. Our observations support the idea that α~11~β~1~ may be expressed in tumors but the corresponding cell lines may lose the expression of this integrin. Previous studies have shown that in cell culture androgen receptor (AR) controls α~2~β~1~ expression. We measured AR mRNA levels and the number of AR positive nuclei in the prostate samples and the results showed a significant correlation between α~2~β~1~ and AR. Androgen receptors may control the mechanisms regulating integrin expression in prostate. © 2005 Wiley‐Liss, Inc.