OBJECTIVES:AlphaB-crystallin (αB-crystallin), a small heat shock protein, has been reported to be involved in the growth, antiapoptosis, migration, and chemoresistance of human malignancies.
MATERIALS AND METHODS:αB-crystallin expression in normal renal and clear cell renal cell carcinoma (ccRCC) tissues was examined with two-dimensional (2D) gel electrophoresis assays. Immunohistochemistry was conducted to determine the presence of αB-crystallin-positive tumor cells and staining intensity in 50 cases of ccRCC tissue samples. The association of αB-crystallin protein expression, clinicopathogic parameters and prognosis of ccRCC patients was also analyzed with Student's t-test and Kaplan-Meier analysis. Moreover, Western blot assays were performed to detect the protein expression of αB-crystallin in normal and tumor tissues and the alteration of cell cycle regulators in αB-crystallin-overexpressing cells. MTT (3-[4,5-dimethythiazol-2-yl]-2,5-diphenyltetrazolium bromide), BrdU, and transwell assays were performed to demonstrate the effects of αB-crystallin overexpression on cell growth, DNA synthesis and cell migration of ccRCC cells, respectively.
RESULTS:The results showed the up-regulation of αB-crystallin expression in ccRCC tissues. Overall survival of ccRCC patients was significantly correlated with αB-crystallin expression in tumor tissues. We found that αB-crystallin overexpression increased the expression of cyclin A and the incorporation of BrdU, which may be related to the enhancement of cell growth. Transwell analyses demonstrated that presence of αB-crystallin overexpression enhanced cell migration in ccRCC cells. Furthermore, rapamycin-resistance of tumor cells was induced when αB-crystallin was overexpressed.
CONCLUSIONS: Our experimental findings highlight the importance of αB-crystallin in the tumor growth, migration, and target therapy-resistance of ccRCC cells.
Written by:
Ho PY, Chueh SC, Chiou SH, Wang SM, Lin WC, Lee IL, Yang HY, Peng HC, Lai MK. Are you the author?
Graduate Institute of Oncology, National Taiwan University, Taipei, Taiwan.
Reference: Urol Oncol. 2012 Mar 12. Epub ahead of print.
doi: 10.1016/j.urolonc.2012.01.015
PubMed Abstract
PMID: 22417627
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