AIM: To develop a prognostic gene set that can predict patient overall survival status based on the whole genome expression analysis. METHODS: Using Illumina HumanWG-6 BeadChip followed by semi-supervised analysis, we analyzed the expression of 47 296 transcripts in two batches of gastric cancer patients who underwent surgical resection. Thirty-nine samples in the first batch were used as the training set to discover candidate markers correlated to overall survival, and thirty-three samples in the second batch were used for validation. RESULTS: A panel of ten genes were identified as prognostic marker in the first batch samples and classified patients into a lowand a high-risk group with significantly different survival times (P = 0.000047). This prognostic marker was then verified in an independent validation sample batch (P = 0.0009). By comparing with the traditional Tumor-node-metastasis (TNM) staging system, this ten-gene prognostic marker showed consistent prognosis results. It was the only independent prognostic value by multivariate Cox regression analysis (P = 0.007). Interestingly, six of these ten genes are ribosomal proteins, suggesting a possible association between the deregulation of ribosome related gene expression and the poor prognosis. CONCLUSION: A ten-gene marker correlated with overall prognosis, including 6 ribosomal proteins, was identified and verified, which may complement the predictive value of TNM staging system.
NCCN即美国癌症综合网(National Comprehensive Cancer Network).是由美国最顶尖的21家美国癌症中心组成的学术联盟。该组织通过文献回顾、专家共识等对常见恶性肿瘤的诊断、治疗进展每年进行更新,“为医生和患者提供当前最佳的治疗建议,改善和提高肿瘤治疗水平”。2007年NCCN首次和中国肿瘤专家合作,推出NCCN中国版,
目的 建立一种SYBR Green Ⅰ荧光定量PCR检测血清miR-21方法,并初步探讨其对乳腺癌诊断的应用价值.方法 用Trizol试剂提取血清总RNA.用茎环引物将miR-16(作为miR-21内参基因)与miR-21分别逆转录成相应cDNA.再用SYBR Green Ⅰ荧光定量RT-PCR对cDNA进行扩增、检测.然后,通过信噪比(signal to noise ratio,SNR)分析试验的准确性;通过熔解曲线评价试验的特异性;通过标准曲线的R2评估试验的精确性;通过批内和批间差异计算试验的稳定性.另外,用自建方法检测33例乳腺癌患者、18例乳腺良性疾病和49名健康人群血清miR-21和miR-16水平,并根据乳腺癌组与健康对照组中miR-21相对表达量确定临界值,以评价其对乳腺癌诊断的敏感度、特异度.结果 通过PCR退火与延伸在温度和时间上的优化,本试验所建立方法SNR≥99.36%;熔解曲线为单峰;标准曲线R3=0.994 8;批内CV< 1.5%,批间CV< 4%.以miR-16为内参,用自建SYBR Green Ⅰ荧光定量PCR检测乳腺癌组、良性疾病组与健康对照组血清miR-21的相对表达量分别为20.83±18.18、20.86±10.11和9.33±4.44,经Kruskal Wallis检验,3组间表达量差异有统计学意义(x2=16.92,P<0.001),且健康对照组与乳腺癌组、健康对照组与良性疾病组间的差异均有统计学意义(Z值分别为-2.58、-4.42,P均≤0.01),而乳腺癌组与良性疾病组血清miR-21表达量差异无统计学意义(Z=-0.51,P=0.608).以miR-21相对表达量18.32为临界值,其对乳腺癌诊断的敏感度为51.5%(17/33),特异度为93.9%(46/49).结论 建立了一种较敏感、特异、稳定的SYBRGreen Ⅰ荧光定量PCR检测血清miR-21方法,该方法对乳腺癌的诊断可能有一定价值.
国际癌症基因组协作组(International Cancer Genome Consortium,ICGC)第一次工作会议于2008年11月15—17日在美国首都华盛顿召开,来自澳大利亚、加拿大、中国(包括香港地区)、法国、德国、印度、13本、荷兰、新加坡、英国、美国(出席国家按照英文名称首字母排列)的一百多位肿瘤与人类基因组专家出席会议。