Anai Satoshi, Tanaka Motoyoshi, Shiverick Kathleen T, Kim Wanju, Takada Satoshi, Boehlein Susan, Goodison Steve, Mizokami Atushi, Rosser Charles J
Division of Urology, University of Florida, Jacksonville, Florida 32209, USA.
J Urol. 2007 May;177(5):1913-7. doi: 10.1016/j.juro.2007.01.019.
Cyclooxygenase-2 functions as a survival factor by protecting cells from apoptosis. We analyzed cyclooxygenase-2 expression in LNCaP-COX-2 and LNCaP-Neo cell lines treated with irradiation.
LNCaP-COX-2 and LNCaP-Neo cells were treated with 0 to 500 microM celecoxib and a dose response curve was generated. A clonogenic assay was performed in which cells were subjected to irradiation (0 to 6 Gy) with or without celecoxib. Cyclooxygenase-2 protein and other relevant proteins were measured by immunohistochemistry Western blot analysis after irradiation and celecoxib treatment.
The 2 studied cell lines experienced cytotoxic effects of celecoxib in a dose related manner. Clonogenic assays demonstrated that LNCaP-COX-2 cells were significantly more resistant to radiation therapy than LNCaP-Neo cells. Furthermore, the addition of celecoxib sensitized LNCaP-Neo and LNCaP-COX-2 cells to the cytocidal effects of radiation. Moreover, cyclooxygenase-2 over expression was associated with the over expression of pAkt and carbonic anhydrase. In this cell line irradiation alone was associated with increased expression of cyclooxygenase-2 and carbonic anhydrase. Combination therapy with irradiation and celecoxib down-regulated cyclooxygenase-2, pAKT and carbonic anhydrase. LNCaP-Neo cells expressed carbonic anhydrase and pAkt. Irradiation of these cells increased carbonic anhydrase and pAkt expression. Combination therapy with irradiation and celecoxib down-regulated carbonic anhydrase and pAkt.
Cyclooxygenase-2 expression is also associated with pAkt and carbonic anhydrase expression. Down-regulation of cyclooxygenase-2 by celecoxib is associated with decreased expression of cyclooxygenase-2, pAkt and carbonic anhydrase, and eventual radiation sensitization, which is a phenomenon that may have clinical usefulness.
环氧化酶-2通过保护细胞免于凋亡而发挥生存因子的作用。我们分析了用辐射处理的LNCaP-COX-2和LNCaP-Neo细胞系中环氧化酶-2的表达。
用0至500微摩尔的塞来昔布处理LNCaP-COX-2和LNCaP-Neo细胞，并绘制剂量反应曲线。进行克隆形成试验，其中细胞在有或没有塞来昔布的情况下接受辐射（0至6 Gy）。在辐射和塞来昔布处理后，通过免疫组织化学和蛋白质印迹分析测量环氧化酶-2蛋白和其他相关蛋白。
所研究的两种细胞系对塞来昔布的细胞毒性作用呈剂量相关方式。克隆形成试验表明，LNCaP-COX-2细胞比LNCaP-Neo细胞对放射治疗的抗性明显更强。此外，添加塞来昔布使LNCaP-Neo和LNCaP-COX-2细胞对辐射的杀伤作用敏感。而且，环氧化酶-2的过表达与pAkt和碳酸酐酶的过表达相关。在该细胞系中，单独辐射与环氧化酶-2和碳酸酐酶的表达增加相关。辐射与塞来昔布联合治疗下调了环氧化酶-2、pAKT和碳酸酐酶。LNCaP-Neo细胞表达碳酸酐酶和pAkt。对这些细胞进行辐射增加了碳酸酐酶和pAkt的表达。辐射与塞来昔布联合治疗下调了碳酸酐酶和pAkt。
环氧化酶-2的表达也与pAkt和碳酸酐酶的表达相关。塞来昔布下调环氧化酶-2与环氧化酶-2、pAkt和碳酸酐酶表达的降低以及最终的放射增敏相关，这是一种可能具有临床应用价值的现象。
