SIRT1表达水平与肿瘤患者预后关系的研究
2018-05-29王一涵李龙浩方文姬重庆医科大学附属第一医院肿瘤科重庆400016
王一涵,赵 斌,李龙浩,方文姬,陈 英,张 涛(重庆医科大学附属第一医院肿瘤科,重庆400016)
恶性肿瘤是全球主要死亡原因之一,每年新发例数与死亡例数分别达到1 410万和820万[1-2],因此,寻找潜在的肿瘤生物标志物用以指导临床决策有重要意义。沉默信息调节因子1(SIRT1)是一种依赖于烟酰胺腺嘌呤二核苷酸的脱乙酰酶[3]。有研究表明,SIRT1主要通过修饰组蛋白参与细胞生长、代谢、凋亡、肿瘤发生及耐药等多种过程[4]。SIRT1 在肺癌[5]、肝癌[6]、结直肠癌[7]、淋巴瘤等多种恶性肿瘤组织中高表达[8]。SIRT1表达水平与肿瘤患者的预后有一定关联,但各研究报道结果并不完全一致。本研究拟通过meta分析评价
SIRT1在肿瘤患者预后评估中的价值。
1 材料与方法
1.1 资料
1.1.1 文献检索策略 利用计算机检索PubMed、EMBASE、Cochrane library数据库中从建库至2017年12月31日公开发表的关于SIRT1与肿瘤预后相关性的英文文献。检索词包括:sirtuin1、SIRT1、cancer、carcinoma、neoplasm、tumor、prognosis、outcome、survival。对相关参考文献进行扩展检索。
1.1.2 纳入与排除标准 纳入标准:(1)研究对象为病理确诊的肿瘤患者;(2)描述了SIRT1表达水平与肿瘤患者临床结局的关系。排除标准:(1)综述、案例报道、动物或细胞系研究;(2)无法获取相关临床结局指标的风险比(HR)及 95% 置信区间(CI);(3)非英文文献。如果一篇文献内包括2个及以上试验,并且报道了不同结局,将作为独立研究进行数据提取。
1.2 方法
1.2.1 资料提取 数据由2名研究者独立提取,包括:(1)文献基本信息;(2)临床信息(肿瘤类型、样本量、随访时间);(3)SIRT1 检测方法及临界值;(4)临床结局指标的HR及95%CI。
1.2.2 文献质量评价 采用纽卡斯尔-渥太华量表对纳入文献进行质量评价。总分为9分。
1.3 统计学处理 本研究所有分析均采用Stata 12.0软件。效应量选取HR及95%CI,若文献未直接提供,按TIERNEY[9]推荐的方法计算。分析各研究间的异质性采用χ2检验,若各研究结果间存在明显异质性,则需采用亚组分析或敏感度分析探索其异质性的来源。通过漏斗图、Begg′s检验评估发表偏倚。以P<0.05为差异有统计学意义。
2 结果
2.1 文献检索结果 初步检索获得相关文献578篇。仔细阅读题目及摘要后,得到初筛文献52篇。进一步阅读全文,最终纳入英文文献[10-43]34篇,共7 311例患者。其中,文献[21,39]均可再分为2个独立研究进行数据提取及分析。文献检索流程及结果,见图1。34篇纳入文献发表于2009—2017年,均采用免疫组织化学测定SIRT1的表达。质量评分为6~8分。见表1。
图1 文献筛选流程及结果
表1 纳入研究的基本特征
续表1 纳入研究的基本特征
2.2 meta分析结果 纳入文献中,33篇文献(包含6 874例患者)报道了SIRT1表达水平与OS的关系。分析结果显示,与SIRT1低表达比较,SIRT1高表达的肿瘤患者 OS 时间缩短(HR=1.66,95%CI为 1.36~2.02,P=0.000),见图2。亚组分析结果显示,按照肿瘤类型分组,消化道肿瘤与非消化道肿瘤均显示SIRT1高表达患者 OS时间缩短(消化道肿瘤HR=1.46,95%CI为1.17~1.82,I2=75.2%;非消化道肿瘤HR=2.04,95%CI为1.38~3.00,I2=79.2%);按照 HR 计算方法分组,单变量分析组异质性明显下降(HR=1.75,95%CI为 1.33~2.29,I2=47.7%),多变量分析组仍存在明显异质性(HR=1.62,95%CI为 1.26~2.08,I2=82.4%)。
图2 SIRT1高表达与肿瘤患者OS关系的meta分析森林图
纳入文献中,6篇文献(包含1 492例患者)报道了SIRT1表达水平与RFS的关系。分析结果显示,SIRT1高表达的肿瘤患者RFS时间缩短,差异有统计学意义(HR=1.71,95%CI为 1.03~2.83,P=0.039),见图 3。
图3 SIRT1高表达与肿瘤患者RFS关系的meta分析森林图
纳入文献中,6篇文献(包含1570个患者)报道了SIRT1表达水平与DFS的关系。分析结果显示,SIRT1不同表达水平的肿瘤患者DFS差异无统计学意义(HR=1.23,95%CI为 0.75~2.02,P=0.419),见图 4。
图4 SIRT1高表达与肿瘤患者DFS关系的meta分析森林图
2.3 发表偏倚 33篇文献报道了SIRT1表达水平与OS的关系,漏斗图显示存在发表偏倚(Begg′s test,P=0.002),见图5。采用剪补法将估计缺失的研究纳入后得到校正的合并效应量HR=1.29,95%CI为1.05~1.58,P=0.016。
图5 漏斗图检验发表偏倚
2.4 敏感度分析 SIRT1高表达与肿瘤患者OS的敏感度分析结果,见图6。分析结果显示,每个单独的研究结果对总体合并效应量并无明显影响。
图6 SIRT1高表达与肿瘤患者OS的敏感度分析
3 讨论
SIRT1通过赖氨酸去乙酰化作用调节靶蛋白活性,在胚胎发育、分化及维持自身平衡中发挥重要作用[44]。研究发现,SIRT1同时具有抑制肿瘤及促进肿瘤的双重作用。一方面,SIRT1可以通过维持基因稳定性从而抑制肿瘤发生[45];另一方面,SIRT1也可通过去乙酰化调节相关蛋白的活性,调控上皮间质转化,维持肿瘤干细胞存活,促进肿瘤增殖、侵袭和转移[46]。此外,SIRT1还参与肿瘤细胞获得性耐药[47]。本研究通过meta分析探讨SIRT1表达与肿瘤患者预后的关系。本研究结果显示,与SIRT1低表达肿瘤患者比较,SIRT1高表达患者OS、RFS缩短。SIRT1高表达是肿瘤预后的一个危险因素。本研究结果提示,SIRT1可能作为判断肿瘤预后的标志物及潜在的肿瘤治疗靶点,与其他抗肿瘤药物联合应用可提高治疗效果。
分析发现,研究SIRT1表达水平与肿瘤患者OS的各文献结果存在明显异质性(P=0.000,I2=77.9%)。作者展开了敏感度分析,结果显示,单一研究对总合并效应量并无明显影响。亚组分析显示肿瘤类型、HR计算方法都可能导致异质性的产生。其他因素如患者基线特征(包括年龄、肿瘤分期、分化程度等)、临界值、随访时间等方面的差异也可能是各研究异质性产生的原因。针对纳入研究存在的发表偏倚,作者采用剪补法分析得到校正的合并效应量HR=1.289,95%CI为 1.05~1.58,证实了本研究结果的可靠性。此外,meta分析结果显示,SIRT1高表达与肿瘤患者低 RFS相关(P=0.039),与 DFS无关(P=0.419)。进一步分析发现,研究SIRT1与RFS相关性的文献纳入肿瘤类型包括乳腺癌(39.0%)、头颈部肿瘤(29.3%)、消化道肿瘤(18.3%)及肾癌(13.4%),其中报道的肿瘤分期Ⅲ~Ⅳ期患者所占比例达到52.5%;而SIRT1与DFS相关性的文献纳入肿瘤类型包括乳腺癌(58.5%)及消化道肿瘤(41.5%),Ⅲ~Ⅳ期患者占38.9%。结果提示,RFS、DFS与SIRT1相关性的差异可能是由肿瘤类型及分期的不同所导致。目前,仍需更多临床研究的相关数据,进一步分析SIRT1在不同肿瘤类型及不同肿瘤期别中的预后价值。
本研究仍存在一定局限性:(1)各文献中SIRT1表达水平的临界值不统一;(2)部分研究未直接提供HR值,需要通过生存曲线计算提取估计值,未能获取HR值的文献被排除;(3)报道阳性结果的研究更容易发表;(4)本研究结果可能受到某些混杂因素的影响。因此,对本研究结果的解读应更加谨慎。
综上所述,SIRT1高表达与肿瘤患者的不良预后有一定关系。随着对SIRT1作用机制的深入研究,以及更多高质量临床研究的设计及开展,SIRT1有望作为肿瘤预后标志物及潜在治疗靶点,为临床治疗提供新的思路和方法。
[1]FERLAY J,SOERJOMATARAM I,DIKSHIT R,et al.Cancer incidence and mortality worldwide:sources,methods and major patterns in GLOBOCAN 2012[J].Int J Cancer,2015,136(5):e359-386.
[2]SIEGEL RL,MILLER KD,JEMAL A.Cancer statistics,2016[J].CA Cancer J Clin,2016,66(1):7-30.
[3]郭淑芹,朱春英,张云良.SIRT1与肿瘤[J].国际肿瘤学杂志,2011,38(8):596-572.
[4]SAUNDERS LR,VERDIN E.Sirtuins:critical regulators at the crossroads between cancer and aging[J].Oncogene,2007,26(37):5489-5504.
[5]GRBESA I,PAJARES MJ,MARTINEZ-TERROBA E,et al.Expression of sirtuin 1 and 2 is associated with poor prognosis in non-small cell lung cancer patients[J].PLoS ONE,2015,10(4):e0124670.
[6]CHEN J,ZHANG B,WONG N,et al.Sirtuin 1 is upregulated in a subset of hepatocellular carcinomas where it is essential for telomere maintenance and tumor cell growth[J].Cancer Res,2011,71(12):4138-4149.
[7]KRIEGL L,VIETH M,KIRCHNER T,et al.Up-regulation of c-MYC and SIRT1 expression correlates with malignant transformation in the serrated route to colorectal cancer[J].Oncotarget,2012,3(10):1182-1193.
[8]NIHAL M,AHMAD N,WOOD GS.SIRT1 is upregulated in cutaneous T-cell lymphoma,and its inhibition induces growth arrest and apoptosis[J].Cell Cycle,2014,13(4):632-640.
[9]TIERNEY JF,STEWART LA,GHERSI D,et al.Practical methods for incorporating summary time-to-event data into meta-analysis[J].Trials,2007,8(1):16.
[10]QIU G,LI X,WEI C,et al.The Prognostic Role of SIRT1-Autophagy Axis in Gastric Cancer[J].Dis Markers,2016,2016(6):6869415.
[11]CHEN HC,JENG YM,YUAN RH,et al.SIRT1 promotes tumorigenesis and resistance to chemotherapy in hepatocellular carcinoma and its expression predicts poor prognosis[J].Ann Surg Oncol,2012,19(6):2011-2019.
[12]CHENG F,SU L,YAO C,et al.SIRT1 promotes epithelial-mesenchymal transition and metastasis in colorectal cancer by regulating Fra-1 expression[J].Cancer Lett,2016,375(2):274-283.
[13]JIN MS,HYUN CL,PARK IA,et al.SIRT1 induces tumor invasion by targeting epithelial mesenchymal transition-related pathway and is a prognostic marker in triple negative breast cancer[J].Tumour Biol,2016,37(4):4743-4753.
[14]NOSHO K,SHIMA K,IRAHARA N,et al.SIRT1 histone deacetylase expression is associated with microsatellite instability and CpG island methylator phenotype in colorectal cancer[J].Mod Pathol,2009,22(7):922-932.
[15]ZHANG T,RONG N,CHEN J,et al.SIRT1 expression is associated with the chemotherapy response and prognosis of patients with advanced NSCLC[J].PLoS One,2013,8(11):e79162.
[16]LI C,WANG L,ZHENG L,et al.SIRT1 expression is associated with poor prognosis of lung adenocarcinoma[J].Onco Targets Ther,2015,8(1):977-984.
[17]NOGUCHI A,LI X,KUBOTA A,et al.SIRT1 expression is associated with good prognosis for head and neck squamous cell carcinoma patients[J].Oral Surg Oral Med Oral Pathol Oral Radiol,2013,115(3):385-392.
[18]NOGUCHI A,KIKUCHI K,ZHENG H,et al.SIRT1 expression is associated with a poor prognosis,whereas DBC1 is associated with favorable outcomes in gastric cancer[J].Cancer Med,2014,3(6):1553-1561.
[19]JANG KY,NOH SJ,LEHWALD N,et al.SIRT1 and c-Myc promote liver tumor cell survival and predict poor survival of human hepatocellular carcinomas[J].PLoS One,2012,7(9):e45119.
[20]JUNG W,HONG KD,JUNG WY,et al.SIRT1 Expression Is Associated with Good Prognosis in Colorectal Cancer[J].Korean J Pathol,2013,47(4):332-339.
[21]SONG S,LUO M,SONG Y,et al.Prognostic role of SIRT1 in hepatocellular carcinoma[J].J Coll Physicians Surg Pak,2014,24(11):849-854.
[22]WANG J,WANG C.Prognostic and Predictive Role of Sirtuin1 Expression in Lung Adenocarcinoma[J].Clin Lab,2016,62(10):1989-1994.
[23]HE Z,YI J,JIN L,et al.Overexpression of Sirtuin-1 is associated with poor clinical outcome in esophageal squamous cell carcinoma[J].Tumour Biol,2016,37(6):7139-7148.
[24]HAO C,ZHU PX,YANG X,et al.Overexpression of SIRT1 promotes metastasis through epithelial-mesenchymal transition in hepatocellular carcinoma[J].BMC Cancer,2014,14(1):978.
[25]MVUNTA DH,MIYAMOTO T,ASAKA R,et al.Overexpression of SIRT1 is Associated With Poor Outcomes in Patients With Ovarian Carcinoma[J].Appl Immunohistochem Mol Morphol,2017,25(6):415-421.
[26]SHUANG T,WANG M,ZHOU Y,et al.Over-expression of Sirt1 contributes to chemoresistance and indicates poor prognosis in serous epithelial ovarian cancer(EOC)[J].Med Oncol,2015,32(12):260.
[27]CHUNG SY,JUNG YY,PARK IA,et al.Oncogenic role of SIRT1 associated with tumor invasion,lymph node metastasis,and poor disease-free survival in triple negative breast cancer[J].Clin Exp metastasis,2016,33(2):179-185.
[28]BENARD A,GOOSSENS-BEUMER IJ,HOESEL AQ,et al.Nuclear expression of histone deacetylases and their histone modifications predicts clinical outcome in colorectal cancer[J].Histopathology,2015,66(2):270-282.
[29]JANG SH,MIN KW,PAIK SS,et al.Loss of SIRT1 histone deacetylase expression associates with tumour progression in colorectal adenocarcinoma[J].J Clin Pathol,2012,65(8):735-739.
[30]DERR RS,HOESEL AQ,BENARD A,et al.High nuclear expression levels of histone-modifying enzymes LSD1,HDAC2 and SIRT1 in tumor cells correlate with decreased survival and increased relapse in breast cancer patients[J].BMC Cancer,2014,14(1):604.
[31]CHEN X,SUN K,JIAO S,et al.High levels of SIRT1 expression enhance tumorigenesis and associate with a poor prognosis of colorectal carcinoma patients[J].Sci Rep,2014,4(1):7481.
[32]STENZINGER A,ENDRIS V,KLAUSCHEN F,et al.High SIRT1 expression is a negative prognosticator in pancreatic ductal adenocarcino-ma[J].BMC Cancer,2013,13(1):450.
[33]WU M,WEI W,XIAO X,et al.Expression of SIRT1 is associated with lymph node metastasis and poor prognosis in both operable triple-negative and non-triple-negative breast cancer[J].Med Oncol,2012,29(5):3240-3249.
[34]KIM JR,MOON YJ,KWON KS,et al.Expression of SIRT1 and DBC1 is associated with poor prognosis of soft tissue sarcomas[J].PLoS One,2013,8(9):e74738.
[35]FENG H,GUO P,WANG J,et al.Expression of Leptin and Sirtuin-1 is associated with poor prognosis in patients with osteosarcoma[J].Pathol Res Pract,2016,212(4):319-324.
[36]CHA EJ,NOH SJ,KWON KS,et al.Expression of DBC1 and SIRT1 is associated with poor prognosis of gastric carcinoma[J].Clin Cancer Res,2009,15(13):4453-4459.
[37]LEE H,KIM KR,NOH SJ,et al.Expression of DBC1 and SIRT1 is associated with poor prognosis for breast carcinoma[J].Hum Pathol,2011,42(2):204-213.
[38]CAO YW,LI WQ,WAN GX,et al.Correlation and prognostic value of SIRT1 and Notch1 signaling in breast cancer[J].J Exp Clin Cancer Res,2014,33(1):97.
[39]ZHANG S,HUANG S,DENG C,et al.Co-ordinated overexpression of SIRT1 and STAT3 is associated with poor survival outcome in gastric cancer patients[J].Oncotarget,2017,8(12):18848-18860.
[40]LV L,SHEN Z,ZHANG J,et al.Clinicopathological significance of SIRT1 expression in colorectal adenocarcinoma[J].Med Oncol,2014,31(6):965.
[41]ZHANG LH,HUANG Q,FAN XS,et al.Clinicopathological significance of SIRT1 and p300/CBP expression in gastroesophageal junction(GEJ)cancer and the correlation with E-cadherin and MLH1[J].Pathol Res Pract,2013,209(10):611-617.
[42]ZHANG W,LUO J,YANG F,et al.BRCA1 inhibits AR-mediated proliferation of breast cancer cells through the activation of SIRT1[J].Sci Rep,2016,6(1):22034.
[43]NOH SJ,KANG MJ,KIM KM,et al.Acetylation status of P53 and the expression of DBC1,SIRT1,and androgen receptor are associated with survival in clear cell renal cell carcinoma patients[J].Pathology,2013,45(6):574-580.
[44]王鑫鑫,吴梦,周思欣,等.SIRT1与代谢及肿瘤的关系[J].山东医药,2013,53(8):90-93.
[45]马威,卢颖,毛俊,等.SIRT1基因在肿瘤中的作用机制[J].国际肿瘤学杂志,2015,42(1):40-42.
[46]陈厚早,张祝琴,韦玉生,等.去乙酰化酶SIRT1的研究进展[J].中国医学科学院学报,2007,29(3):441-447.
[47]周琰,姚阳.沉默信息调节因子1与肿瘤耐药相关研究进展[J].癌症进展,2013,11(4):345-350.