肿瘤内胶原纤维丰度和假包膜状态与肾透明细胞癌患者预后的相关性

The correlation of intratumoral fibrosis with the prognosis of clear cell renal cell carcinoma

目的探讨肾透明细胞癌(ccRCC)肿瘤内胶原纤维丰度和纤维性假包膜状态与患者预后的关系。方法检索癌症基因组图谱(TCGA)数据库中530例ccRCC患者的资料。男344例,女186例。年龄≤60岁264例,>60岁266例;G_(1-2)级241例,G_(3-4)级281例,未确定分级8例;2017年美国癌症联合委员会(AJCC)分期Ⅰ~Ⅱ期322例,Ⅲ~Ⅳ期205例,未确定分期3例;M0期420例,M1期78例,无法评估远处转移情况32例。采用R语言和RStudio软件,分析ccRCC中编码Ⅰ型胶原的COL1A1 mRNA水平与患者预后的相关性。回顾性分析北京大学人民医院2005年11月至2017年11月病理证实的158例非囊性ccRCC患者的资料。男112例,女46例;年龄≤60岁100例,>60岁58例;G_(1-2)级111例,G_(3-4)级47例;AJCC分期Ⅰ~Ⅱ期144例,Ⅲ~Ⅳ期14例。取患者石蜡切片进行Masson染色、天狼星红染色和多色免疫荧光染色,评估肿瘤组织内及假包膜的胶原纤维丰度,采用HE染色评估ccRCC纤维性假包膜状态。Kaplan-Meier生存曲线分析肿瘤内胶原纤维丰度和纤维性假包膜状态与ccRCC患者总生存率的关系。结果TCGA数据库的转录组学结果提示,ccRCC肿瘤组织COL1A1 mRNA表达水平高于癌旁正常组织(P<0.001);COL1A1 mRNA高表达组患者总生存率显著低于低表达组(HR=1.165,P=0.002);高COL1A1/COL3A1 mRNA比值患者的总生存率低于低COL1A1/COL3A1 mRNA比值者(HR=1.901,P<0.001)。对本中心30例肿瘤组织及癌旁正常组织行Masson染色,结果显示肿瘤组织胶原纤维丰度高于癌旁组织[41.0(14.0~75.0)与15.0(3.0~57.0),P<0.001];天狼星红染色结果也显示肿瘤组织胶原纤维丰度高于癌旁组织[42.5(10.0~90.0)与10.0(2.5~60.0),P<0.001]。高胶原纤维组ccRCC患者的病理分级G_(3-4)级比例高于低胶原纤维组[38.5%(30/78)与21.3%(17/80),OR=2.316,95%CI 1.146~4.681,P=0.023]。158例中位随访时间73.5(4~135)个月。Kaplan-Meier生存曲线分析结果显示,低胶原纤维组5年总生存率显著高于高胶原纤维组(88.75%与74.36%,HR=2.630,P=0.007)。纤维性假包膜不完整者5年总生存率显著低于纤维性假包膜完整者(52.94%与85.11%,HR=11.140,P<0.001)。结论ccRCC肿瘤内胶原纤维水平呈现过度表达,肿瘤内胶原纤维富集、纤维性假包膜不完整可能提示较差的生存预后。

Objective To investigate the correlation of intratumoral fibrosis with the prognosis of clear cell renal cell carcinoma(ccRCC).Methods The correlation of the transcriptional expression of the primary collagen with the prognosis in ccRCC was evaluated using the Cancer Genome Atlas(TCGA)database,including 530 ccRCC patients with complete information.Of them,344 cases were male,186 cases were female.The age of 264 cases was≤60 years,and the age of 266 cases was>60 years.The pathology grade of 241 patients was G_(1-2) grade,and the pathology of 281 cases were G_(3-4) grade,8 cases were undetermined grade.There were 322 cases with AJCC stageⅠ-Ⅱand 205 cases with AJCC stageⅢ-Ⅳ,and 3 cases with undetermined stage.There were 420 cases in M0 and 78 cases in M1,and 32 cases without distant metastases information.Furthermore,the paraffin sections of 158 non-cystic ccRCC patients confirmed by pathology from November 2005 to November 2017 were further used to evaluate the level of collagen of ccRCC and the status of the pseudocapsule by the Masson staining,Sirius red staining and multicolor immunofluorescence staining of collagenⅠand collagenⅢ.Of them,112 cases were male,46 cases were female.There were 100 cases with age≤60 years,and 58 cases with age>60 years.The pathology grade of 111 cases were G_(1-2),and the pathology grade of 47 cases were G_(3-4).There were 144 cases with AJCC stageⅠ-Ⅱ,14 cases with AJCC stageⅢ-Ⅳ.Kaplan-Meier survival curve were used to analyze the relationship between tumor collagen parameters and the overall survival prognosis of patients with ccRCC.Results The transcriptome results of the TCGA database indicated that the expression level of COL1A1 in ccRCC tissues was significantly higher than that in adjacent normal tissues(P<0.001).The high expression of collagen suggested a worse overall survival prognosis(HR=1.165,P=0.002).In addition,the high ratio of COL1A1/COL3A1 indicated a worse overall survival prognosis(HR=1.901,P<0.001)compared with the low ratio.We further confirmed that the abundance of collagen in tumor was significantly increased compared with the normal adjacent tissues by the Masson staining[41.0(14.0-75.0)vs.15.0(3.0-57.0),P<0.001]and the Sirius red staining[42.5(10.0-90.0)vs.10.0(2.5-60.0),P<0.001]on 30 ccRCC tissues and adjacent normal tissues.Based on the Masson staining,we found that high collagen abundance in tumor tissue was associated with more G_(3-4) grade of tumor compared with low collagen abundance(38.5%vs.21.3%,OR=2.316,95%CI 1.146-4.681,P=0.023).Kaplan-Meier survival curve showed that higher collagen abundance was associated with a worse overall survival prognosis in ccRCC(HR=2.630,P=0.007).However,incomplete fibrous pseudocapsule was associated with a worse overall survival prognosis(HR=11.140,P<0.001).Conclusions In ccRCC,intratumoral collagen fiber level was overexpressed.High intratumoral collagen level and incomplete fibrous pseudocapsule may indicate a poor overall survival prognosis.