The Study On Clinical Revelance Of Tumor Budding In Early-stage Cervical Cancer And Its Molecular Mechanisms

Part ?High-grade tumor budding stratifies early-stage cervical cancer with recurrence riskObjectivesThis study investigated prognostic significance of tumor budding in early-stage cervical cancer(ECC)following radical surgery and its contribution to improve the stratification of patients with recurrence risk.MethodsWe reviewed the archival medical records and hematoxylin and eosin(H&E)-stained slides of cervical cancer patients at Union Hospital,Tongji Medical College,Huazhong University of Science and Technology.ECC(FIGO stage IA2-?A)patients who had undergone primary radical surgery between January 2008 and December 2014 were enrolled.Tumor budding is morphologically defined as the presence of single tumor cells or isolated small clusters of tumor cells(up to 5 tumor cells)scattered in the stroma at the invasive front.The number of buds was counted in a field that measured 0.95 mm2 using a×20 objective lens in the areas with the most intense buds.Associations between the number of buds and the categorical clinicopathological parameters were examined using the Wilcoxon signed-rank test.A receiver operating characteristic(ROC)curve analysis was performed to assess the performance of bud counts to discriminate recurrences from non-recurrences and to determine a valid cut-off value to divide patients into a high-grade tumor budding(HTB)group and a low-grade tumor budding(LTB)group.Kaplan-Meier survival analyses were used to estimate the disease-free survival(DFS)function;log-rank tests were used to identify the statistical significance of the differences between the subgroups.We established nine models that included HTB and the classic risk factors to stratify the ECC patients with recurrence risk;the performance was compared between the novel prediction models and classic criteria via log-rank test and receiver operating characteristic(ROC)analysis.ResultsSix hundred forty-three cases satisfied the eligibility criteria and were enrolled in the present study.Tumor budding was significantly associated with poor differentiation,high FIGO stage,deep stromal invasion,lymph node metastasis and lymphovascular space invasion(LVSI).The ROC curve analysis indicated that the number of buds offered an area under the curve(AUC)of 0.780 to distinguish the patients with recurrences from the patients with non-recurrences.Five was selected as the cut-off value to divide the patients because 5 buds exhibited the highest accuracy with a sensitivity of 65.1%and a specificity LTB group(0-4 buds,N = 445,69.2%)and HTB group(5 or more buds,N = 198,30.8%).Tumors with HTB exhibited a substantially increased risk of recurrence(hazard ratio =4.711,95%CI:3.051-7.275,P<0.001).Nine predictive models for recurrence were established,in which HTB was combined with recognized risk factors.The model using of at least two risk factors of HTB,tumor size ? 4 cm,deep stromal invasion(outer 1/3),and LVSI to stratify patients with an intermediate-risk was most predictive of recurrence with improved sensitivity and specificity compared with the classic criteria.ConclusionsTumor budding is an independent,unfavorable,prognostic factor for patients with ECC following radical surgery and holds promise for improved recurrence risk stratification.Part ?SATB1 promotes tumor budding in early-stage cervical cancer via epithelial-mesenchymal transitionObjectivesTo investigate the SATB1 expression in early-stage cervical cancer and clarify its role in tumor budding of cervical cancer.MethodsFIGO stage IB1 patients who had undergone primary radical surgery between January 2008 and December 2012 were enrolled.Immunohistochemical staining was employed to examine the SATB1 expression in cervical cancer.Associations between the score of SATB1 expression and the number of tumor buds were examined using the Spearman's rank correlation analysis.Kaplan-Meier survival analysis was used to estimate the prognostic relevance of SATB1 and the difference between groups was assessed by the log-rank test.The mRNA levels of SATB1 in cervical cancer cell lines were examined by TagMan real-time quantitative PCR.To explore the role of SATB1 in maintaining malignant phenotype of the cell,the study was carried out by silencing SATB1 expression.We then performed Transwell assays and EdU to investigate the effects of down-regulation SATB1 expression on migration and invasion and proliferation of cervical cancer cells in vitro,respectively.The mRNA and protein levels of several epithelial-mesenchymal transition(EMT)related genes were also examined by real-time quantitative PCR and western blot,respectively.Using immunohistochemical staining,E-cadherin expression was detected in early-stage cervical cancer tissue specimens;relationships between SATB1 and E-cadherin were analyzed by Spearman's rank correlation analysis.Subcutaneous Siha xenografts athymic mouse models were established and the effects of down-regulation SATB1 expression on growth and invasion of Siha in vivo were investigated.ResultsTwo hundred cases satisfied the eligibility criteria and were enrolled in the present study.Immunohistochemical staining showed over-expression of SATB1 was positively ccorrelated with the number of tumor buds in early-stage cervical cancer.In addition,SATB1 staining score was correlated poor clinical outcomes in early-stage cervical cancer.After down-regulating the expression of SATB1,the invasion and migration of cervical cancer cells were significantly depressed;the proliferation of cervical cancer cells was significantly decreased.We also found that knockdown of SATB1 dramatically altered several EMT related gene expressions on both mRNA level and protein level in vitro.In cervical cancer tissue specimens,significantly inverse correlations were observed between SATB1 level and expressions of E-cadherin.In subcutaneous Siha xenografts athymic mouse models,the down-regulation of SATB1 dramatically inhibited the growth and invasion of Siha cells.ConclusionsThis findings indicate that upregulation of SATB1 may play critical role in the acquisition of an aggressive phenotype and promote tumor budding in early-stage cervical cancer by induction of EMT.SATB1 is a promising biomarker and novel therapeutic target of cervical cancer.