Laboratory of Experimental Biomedicine, University of Tarapaca, Campus Esmeralda, Iquique, Chile.
Oncol Rep. 2013 Oct;30(4):1936-42. doi: 10.3892/or.2013.2637. Epub 2013 Jul 24.
Cisplatin is one of the most effective and widely used chemotherapeutic agents against several types of human cancers. However, the underlying mechanisms of action are not fully understood. We aimed to investigate the possible molecular mechanism(s) of acquired chemoresistance observed in prostate cancer cells treated with cisplatin. Human LNCaP cells (bearing wild-type p53) and PC-3 cells (lacking p53) were used. The expression levels of protein were determined by western blotting, and the mRNA levels were determined by reverse transcription-polymerase chain reaction (RT-PCR). Cell viability was measured by MTT assay, and the transcriptional effect of small interfering RNA (siRNA) was measured by luciferase reporter gene. We showed that cisplatin treatment increased JNK-1 and JNK-2 activity and expression in both LNCaP and PC-3 cells. In addition, the knockdown of JNK-1 expression by siRNA-JNK-1 or siRNA-JNK-2 significantly impaired the upregulation of AP-1 luciferase reporter gene, but failed to decrease the levels of AP-1 reporter gene expression induced by TPA treatment. Our observations indicate that JNK-1 and JNK-2 may be involved in the chemoresistance observed in prostate cancer cells treated with cisplatin and that blocking the stimulation of Jun kinase (JNK) signaling may be important for regulating the susceptibility to cisplatin of prostate cancer.
顺铂是一种针对多种人类癌症最有效和最广泛使用的化疗药物之一。然而，其作用的潜在机制尚不完全清楚。我们旨在研究顺铂处理的前列腺癌细胞中观察到的获得性耐药的可能分子机制。使用了人 LNCaP 细胞（携带野生型 p53）和 PC-3 细胞（缺乏 p53）。通过 Western 印迹测定蛋白表达水平，通过逆转录-聚合酶链反应（RT-PCR）测定 mRNA 水平。通过 MTT 测定细胞活力，通过荧光素酶报告基因测定小干扰 RNA（siRNA）的转录效应。我们表明，顺铂处理增加了 LNCaP 和 PC-3 细胞中 JNK-1 和 JNK-2 的活性和表达。此外，siRNA-JNK-1 或 siRNA-JNK-2 敲低 JNK-1 表达显著削弱了 AP-1 荧光素酶报告基因的上调，但未能降低 TPA 处理诱导的 AP-1 报告基因表达水平。我们的观察表明，JNK-1 和 JNK-2 可能参与了顺铂处理的前列腺癌细胞中的耐药性，阻断 Jun 激酶（JNK）信号的刺激对于调节前列腺癌细胞对顺铂的敏感性可能很重要。
