结直肠癌原发灶中CXCR6的表达与临床意义

目的: 明确趋化因子受体CXCR6在结直肠癌原发灶中的表达特点及临床意义。方法: 收集2004年8月至2008年12月中山大学附属第一医院手术切除的143例结直肠癌标本及29例癌旁组织,应用免疫组化方法检测CXCR6的表达,采用Image-Pro Plus 6.0 软件分析图片的平均累积吸光度(mIA),分析CXCR6与同时性肝转移及预后的关系。结果: CXCR6在结直肠癌组织中呈不同程度的阳性表达,在癌旁正常组织中弱表达或不表达。结直肠癌原发灶中CXCR6的mIA在0.41~2.84之间,平均为1.54±0.04,其中同时性肝转移病例为1.63±0.05,无肝转移病例为1.41±0.08,两组比较差异有统计学意义(P<0.05)。以mIA值1.54为界,将病例划分为CXCR6低表达组(mIA<1.54)和CXCR6高表达组(mIA≥1.54)。CXCR6高表达患者的总生存率显著较低表达组差,两组差异有统计学意义(P<0.05)。多因素Cox回归分析发现年龄(P<0.05)、淋巴结转移(P<0.05)和同时性肝转移(P<0.01)为结直肠癌患者预后的独立危险因素,CXCR6为非独立危险因素。CXCR6表达与IV期肝转移患者预后无关(P>0.05),与I~III期结直肠癌患者预后呈负相关(P<0.01)。结论: CXCR6与结直肠癌肝转移的发生相关,它有望成为结直肠癌肝转移治疗的一个重要靶点。

Expression and clinical significance of chemokine receptor CXCR6 in primary colorectal cancer

AIM: To investigate the expression of chemokine receptor CXCR6 in primary colorectal cancer and determine the association between CXCR6 expression and synchronous liver metastasis/prognosis.METHODS: The colorectal cancer tissues from 143 patients were collected from August 2004 to December 2008 in the First Affiliated Hospital,Sun Yat-sen University.Twenty-night cases of the adjacent normal colorectal tissues were enrolled as controls.The expression of CXCR6 was detected by immunohistochemistry and the mean intergrated absorbance(mIA) was calculated by Image-Pro Plus 6.0 software.The relationship between CXCR6 expression and synchronous liver metastasis/prognosis was analyzed.RESULTS: The CXCR6 staining was mainly positive in colorectal cancer tissues but not in adjacent normal colorectal tissues.The mIA of CXCR6 in colorectal cancer was 1.54±0.04(range: 0.41~2.84),and was 1.63±0.05 and 1.41±0.08(P<0.05) in the cases with(n=83) or without(n=60) synchronous liver metastasis,respectively.According to the mean mIA of CXCR6(1.54),the cases was divided into high CXCR6 group(mIA≥1.54) and low CXCR6 group(mIA<1.54).The overall survival rate in high CXCR6 group was significantly lower than that in low CXCR6 group(P<0.05).In multivariate Cox regression models,age(P<0.05),lymph node metastasis(P<0.05) and synchronous liver metastasis(P<0.01) but not CXCR6 were identified as independent risk factors for poor outcome.In subgroup analysis,high CXCR6 expression was associated with poorer survival in the patients with stage I~III colorectal cancer(P<0.01) but not those with synchronous liver metastasis(P>0.05). CONCLUSION: CXCR6 in primary colorectal cancer tissues is associated with liver metastasis.It may become a potential target for the treatment of colorectal cancer liver metastasis.