直肠癌新辅助放化疗前后LGR5基因表达的变化及其与疗效的关系

doi:10.3969/j.issn.1004-616x.2017.01.012

摘要/Abstract

摘要：

目的：探讨肿瘤干细胞标记基因LGR5在局部晚期直肠癌新辅助放化疗（放疗同时口服卡培他滨）前后表达的变化，及其对新辅助放化疗效果预测的作用。方法：收集2014年1月-2016年2月在新疆医科大学附属肿瘤医院接受新辅助放化疗并手术治疗的94例局部晚期直肠癌患者临床资料，对其新辅助放化疗前肠镜活检组织及新辅助放化疗后手术切除组织标本采用荧光定量PCR（qPCR）法检测LGR5 mRNA的表达，分析其在新辅助放化疗前后表达水平的变化及其与疗效的关系，采用Kaplan-Meier法进行生存分析，Log-rank法进行单因素预后分析和Cox回归进行多因素预后分析。结果：直肠癌患者接受新辅助放化疗后肿瘤病理退缩反应良好，肿瘤退缩有效率达87.2%，其中病理完全缓解率为18.1%。直肠癌癌组织中LGR5 mRNA的相对表达水平从新辅助放化疗前的14.396±9.924减少到手术后的8.847±6.664，总体表达水平显著下降（P < 0.05）。放化疗后LGR5 mRNA表达上调者27例，表达下调者67例，表达下调组肿瘤病理退缩程度（TRG）和1、2年生存率均明显优于表达上调组（P < 0.05）。单因素生存分析结果显示放化疗前血清CA19-9水平、临床分期、TRG分级和LGR5 mRNA表达差异为直肠癌预后的影响因素（P均 < 0.05）；多因素分析表明放化疗前CA19-9水平和放化疗前后LGR5 mRNA表达差异是直肠癌预后的影响因素（P分别为0.013和0.015）。结论：新辅助放化疗可以诱导LGR5 mRNA表达的改变，检测其表达对于判断直肠癌预后及指导治疗具有参考价值，新辅助放化疗前后LGR5 mRNA表达变化和放化疗前CA19-9水平有可能成为预测局部晚期直肠癌新辅助放化疗效果的参考指标。

关键词: 直肠癌, 新辅助放化疗, LGR5 mRNA, 肿瘤退缩, 疗效

Abstract:

OBJECTIVE: To investigate changes in expression of the tumor stem cell marker LGR5 gene before and after neoadjuvant chemoradiotherapy and its predictive effect on neoadjuvant chemoradiation. METHODS: Ninety-four rectal cancer patients with preoperative chemoradiotherapy were enrolled in the Affiliated Tumor Hospital of Xinjiang Medical University between January 2014 and February 2016. Quantitative real-time PCR(qRT-PCR) method was used to determine the expression of LGR5 mRNA before and after neoadjuvant chemoradiotherapy. Overall survival(OS) rates were estimated by the Kaplan-Meier method and compared using the Log-rank test for univariate analysis. Cox regression analysis was performed to provide multivariate analysis. RESULTS: Tumor pathological regression reaction of rectal cancer after neoadjuvant chemoradiothepy was good. The efficiency was at 87.2%,and 18.1% patients achieved pathological complete response rate (pCR) after neoadjuvant chemoradiothepy. The expression level of LGR5 mRNA in rectal carcinoma tissues after chemoradiothepy (8.847±6.664) was significantly less than that before chemoradiothepy (14.396±9.924;P < 0.05). The expression level of LGR5 mRNA after chemoradiothepy was up-regulated in 27 patients and down-regulated in 67 patients. Among them,the down-regulated group had significantly better tumor regression degree and 1,2 year-survival rates than that of the up-regulated group. Univariate analysis showed that several factors such as the CA19-9 levels before chemoradiothepy, clinical stage,grade of TRG and expression changes of LGR5 mRNA were significant prognostic factor for OS. CA19-9 levels before chemoradiothepy and expression changes of LGR5 mRNA showed significant differences in multivariate analysis. CONCLUSION: Neoadjuvant chemoradiotherapy caused changes in the expression of LGR5 mRNA. Our study shows that LGR5 mRNA expression changes before and after neoadjuvant chemoradiation and levels before chemoradiothepy had the prognostic potential on the effect of neoadjuvant chemoradiation for locally advanced rectal cancer.

Key words: rectal cancer, neoadjuvant chemoradiotherapy, LGR5 mRNA, tumor regression grade, effect

中图分类号:

730.5

阿衣古丽·哈热, 陆艳荣, 伊斯刊达·阿不力米提, 张瑾熔. 直肠癌新辅助放化疗前后LGR5基因表达的变化及其与疗效的关系[J]. 癌变·畸变·突变, 2017, 29(1): 60-64,69.

AYIGULI·Hare, LU Yanrong, YISIKANDA·Abulimiti, ZHANG Jinrong. Expression of the LGR5 gene in rectal cancer in response to neoadjuvant chemoradiotherapy[J]. Carcinogenesis, Teratogenesis & Mutagenesis, 2017, 29(1): 60-64,69.

参考文献

[1] JEMAL A,SIEGEL R,WARD E,et al. Cancer statistics[J]. CA Cancer J Clin,2008,58(2):71-96.

[2] CHEN Q,LIU Z C,CHENG L P,et al. An analysis of incidence and mortality of colorectal cancer in China[J]. China Cancer,2012,21(3):179-182.

[3] VAN GIJN W,MARIJNEN C A M,NAGTEGAAL I D,et al. Preoperative radiotherapy combined with total mesorectal excision for resectable rectal cancer:12-year follow-up of the multicentre,randomised controlled TME trial[J]. Lancet Oncol, 2011,12(6):575-582.

[4] SAUER R,LIERSCH T,MERKEL S,et al. Preoperative versus postoperative chemoradiotherapy for locally advanced rectal cancer:results of the German CAO/ARO/AIO-94 randomized phase Ⅲ trial after ramedian follow-up of 11 years[J].J Clin Oncol,2012,30(16):1926-1933.

[5] DE CAMPOS-LOBATO L F,STOCEHI L,DA LUZ MOREIRA A,et al. Pathologic complete response after neoadjuvant treatment for rectal cancer decreases distant recurrence and could eradicate local recurrence[J]. Ann Surg Oncol,2011,18(6):1590-1598.

[6] MASS M,NELEMANS P J,VALENTINI V,et al. Long-term outcome in patients with a pathological complete response after chemoradiation for rectal cancer:a pooled analysis of individual patient data[J]. Lancet Oncol,2010,11(9):835-844.

[7] MERLOS-SUAREZ A,BARRIGA FM,JUNG P,et al. The intestinal stem cell signature identifies colorectal cancer stem cells and predicts disease relapse[J]. Cell Stem Cell,2011, 8(5):511-524.

[8] WALKER F,ZHANG HH,ODORIZZI A,et al. LGR5 is a negative regulator of tumourigenicity,antagonizes Wnt signalling and regulates cell adhesion in colorectal cancer cell lines[J]. PLoS One,2011,6(7):e22733.

[9] 孙艳,盛春华,文大成,等. 人结直肠癌干细胞标志物富含亮氨酸重复单位的G蛋白偶联受体5基因的表达及意义[J]. 中华消化杂志,2013,33(3):187-190.

[10] REYA T,MORRISON SJ,CIARKE MF,et al. Stem cells, cancer,and cancer stem cells[J]. Nature,2001, 414(6859):105-111.

[11] VISVADER J E,LINDEMAN G J. Cancer stem cells in solid tumours:accumulating evidence and unresolved questions[J]. Nat Rev Cancer,2008,8(10) 755-768.

[12] SIMON E,PETKE D,BOGER C,et al. The spatial distribution of LGR5⁺ cells correlates with gastric cancer progression[J]. PLoS One,2012,7(4):e35486.

[13] WANG D,ZHOU J,FAN C,et al. Knockdown of LGR5 suppresses the proliferation of glioma cells in vitro and in vivo[J]. Oncol Rep,2014,31(1):41-49.

[14] SCANNELL C,PEDERSEN E,MOSHER J,et al. LGR5 is expressed by Ewing sarcoma and potentiates Wnt/β-catenin signaling[J]. Front Oncol,2013,doi:10.3389/fonc.2013. 00081.

[15] WU X S,XI H Q,CHEN L. LGR5 is a potential marker of colorectal carcinoma stem cells that correlates with patient survival[J]. World J Surg Oncol,2012,10(1):244.

[16] NAKATA S,CAMPOS B,BAGERITZ J,et al. LGR5 is a marker of poor prognosis in glioblastoma and is required for survival of brain cancer stem-like cells[J]. Brain Pathol, 2013,23(1):60-72.

[17] LIU Z,DAI W,JIANG L,et al. Over-expression of LGR5 correlates with poor survival of colon cancer in mice as well as in patients[J]. Neoplasma,2014,61(2):177-185.

[18] SAIGUSA S,INOUE Y,TANAKA K,et al. Significant correlation between LKB1 and LGR5 gene expression and the association with poor recurrence-free survival in rectal cancer after preoperative chemoradiotherapy[J]. J Cancer Res Clin Oncol,2013,139(1):131-138.

[19] VON RAHDEN BH,KIRCHER S,LAZARIOTOU M,et al. LgR5 expression and cancer stem cell hypothesis:clue to define the true origin of esophageal adenocarcinomas with and without Barrett's esophagus[J]. J Exp Clin Cancer Res,2011,30(1):23.

[20] 彭亮,梁纯,梁燕,等. 结直肠癌Lgr5表达对患者预后的影响[J]. 现代消化及介入诊疗,2010,15(5):284-287.

[21] WALKER F,ZHANG H H,ODORIZZI A,et al. LGR5 is a negative regulator of tumourigenicity,antagonizes Wm signalling and regulates cell adhesion in colorectal cancer cell lines[J]. PLoS One,2011,6(7):e22733.

[22] ZISKIN J L,DUNLAP D,YAYLAOGLU M,et al. In situ validation of an intestinal stem cell signature in colorectal cancer[J]. Gut,2013,62(7):1012-1023.

[23] 孙艳武,池畔,徐本华,等. 直肠癌新辅助放化疗后病理完全缓解预测因素分析[J]. 中华胃肠外科杂志,2014,17(6):556-560.

[24] SAIGUSA S,INOUE Y,TANAKA K,et al. Significant correlation between LKB1 and LGR5 gene expression and the association with poor recurrence-free survival in rectal cancer after preoperative chemoradiotherapy[J]. Cancer Res Clin Oncol,2013,139(1):131-138.

[25] HSU H C,LIU Y S,TSENG K C,et al.Overexpression of Lgr5 correlates with resistance to 5-FU-based chemotherapy in colorectal cancer[J]. Int J Colorectal Dis,2013,28(11):1535-1546.

[26] KOBAYASHI S,YAMADA-OKABE H,SUZUKI M,et al. LGR5-positive colon cancer stem cells interconvert with drug-resistant LGR5-negative cells and are capable of tumor reconsti-tution[J]. Stem Cells,2012,30(12):2631-2644.

[27] 任俊丽,樊卫平,韩存芝,等. 局部晚期直肠癌新辅助治疗中CEA、CA199的变化及临床意义[J]. 中国当代医药,2015, 22(20):50-56.

[28] 韩潞,江勇,谭卫林. CEA和CA19-9在结直肠癌组织中的表达及临床意义[J]. 实用癌症杂志,2015,30(1):25-27.