结直肠癌中钙离子钙调蛋白依赖性蛋白激酶Ⅱδ的表达及其意义

The research on expression and mechanism of Ca^(2+)/calmodulin-dependent protein kinaseδ in colorectal cancer

目的分析钙离子钙调蛋白依赖性蛋白激酶Ⅱδ体内外的表达情况并探讨其机制,为临床诊断治疗提供新的靶点。方法采用半定量RT-PCR技术检测3种人结直肠癌细胞系、20对结直肠癌组织及其配对癌旁组织中CAMKⅡδmRNA的表达水平;利用Western Blot技术及免疫组化SP技术检测结直肠癌组织及癌旁正常组织中CAMKⅡδ蛋白的表达情况,并结合患者的临床病理参数进行分析。结果CAMKⅡδmRNA水平在3种结直肠癌细胞系中均有较高的表达,其中SW620表达最高,依次为HT-29、RKO。20对结直肠癌组织,有16对癌组织中CAMKⅡδmRNNA表达高于癌旁组织,其值分别是0.48±0.31和0.25±0.16,两者之间有统计学差异(P=0.002)。1 Western Blot的检测结果与RT-PCR的检测结果相一致,同样可以观察到CAMKⅡδ在配对的癌组织中的表达强于癌旁组织(P<0.05)。免疫组化提示CAMKⅡδ在结直肠癌组织中免疫反应强阳性,而癌旁正常组织中表达明显减弱。20例结直肠癌组织标本中,CAMKⅡδ的阳性表达率为55%(11/20),明显高于癌旁正常组织的表达率20%(4/20)。(P=0.022)结论 CAMKⅡδ在结直肠癌细胞系及结直肠癌组织中高表达,提示可能促进肿瘤细胞的不断增殖,与直肠癌的发生发展密切相关。

Objective To investigate the expression and significance of Ca 2＋/calmodulin-dependent Protein kinaseδ（CaMKⅡδ）on colorectal cancer （CRC）. Method The mRNA levels of CaMKⅡδin 3 CRC cell lines,tumor tissues and matched adjacent tissues from 20 CRC patients were examined by RT-PCRby RT-PCR, and identified by immunohistochemistry and Western blotting. Results CaMKⅡδmRNA was high expressed in the 3 colorectal cancer cell lines. SW620 expressed the highest, followed by HT-29, RKO. Sixteen of the 20 tissues had higher expressions of CaMKⅡδ than the adjacent non-tumor tissues. The value was 0.48 ± 0.31, 0.25±0.16 respectively, and there was great significant differences （P=0.002）. The results of Western Blot and RT-PCR were consistent. The expression of CaMKⅡδwas significantly higher in tumor tissues than that in the matched adjacent tissues （ P〈0.05）. The expression of CaMKⅡδ in tumor tissues and adjacent tissues were stained by immunohistochemistry, which response to strongger positive in colorectal cancer tissues than that in the matched adjacent tissues. In 20 cases of colorectal cancer tissues, the positive staining rate of CaMKⅡδwas 55%（11/20）which was significantly higher than that in normal tissue 20% （4/20, P=0.022）. Conclusion The higher expressions of CaMKⅡδin colorectal cancer tissues indicated that CAMKⅡδcan effectively promote the growth of the tumor cells.