Study On The Relationship Between Expression Of DLL4, YKL-40, MMP-9and Prognosis For Patients With Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is one of the most destructive tumors, forwhich surgical resection is the only potentially curative therapeutic option. However, the5-year survival of operated cases is not more than20percent. It's beneficial for clinicalmanagement to explore the factors associated with early recurrence and metastasis aftercurative resection, which may lead to the prognostic improvement for pancreatic cancerpatients.Stromal remodeling and angiogenesis have a significant role in the process ofrecurrence and metastasis of pancreatic cancer for operated cases. Vascular endothelialgrowth factor (VEGF) signal is one of the most important pathways for cancer cells growthand vessels reconstruction in PDAC. It has been demonstrated that one of the Notchligands, delta-like ligand4(DLL4), which is induced by VEGF and acts downstream ofVEGF as a "brake" on VEGF receptor2(VEGFR-2) expression, forming an autoregulatorynegative feedback loop inactivating VEGF-induced vessel growth. Consistent with thisrole, blockade of DLL4results in excessive, nonproductive angiogenesis and then resultsin decreased tumor growth, even for tumors that are resistant to anti-VEGF therapy. Recentevidence has shown that DLL4was expressed highly in several human malignancies, suchas lung cancer, and so on, which was correlated with poor prognosis. Therefore,DLL4-Notch signaling may be involved in pancreatic cancer development and predict poorprognosis for patients.Both YKL-40, also named human cartilage glycoprotein-39(HC-gp39), and matrixmetalloproteinase9(MMP-9) are synthesized and secreted by cancer cells andcancer-associated stromal cells. Previous studies have shown that MMP-9participates indegradation of the vascular basement membrane and remodeling of the ECM to stimulateangiogenesis and enhance VEGF pathway. On the other, it has been indicated that YKL-40can promote neovascularization by boosting VEGFR-2expression in a series of researches.Thus, both YKL-40and MMP-9may promote invasion and metastasis of pancreaticcancer.Our study was designed to investigate the levels of DLL4, YKL-40and MMP-9proteins in pancreatic cancer by immunohistochemistry and assess their prognostic valuesfor patients.1. A study of the relationship between expression of DLL4in cancer tissue andprognosis for patients with pancreatic cancer OBJECTIVE: To determine whether high DLL4expression is correlated with poorprognosis after curative resection for pancreatic ductal adenocarcinoma (PDAC) and assessthe relationship between DLL4expression and VEGF receptor2(VEGFR-2) expressionfor patients with PDAC.METHODS: The project was managed by ambispective cohort study statisticalmethod. From January1,2005, to December31,2009, the consecutive patients with aconfrmed histologic diagnosis of primary PDAC aged18years or older, who underwentmacroscopically curative resection in Changhai Hospital, were recruited in this study. Allmembers had no history of adjuvant therapy before operation. We reviewed all valuablemedical information during their hospitalization, which consisted of demologycharacteristics, private habits, medical history, clinical manifestation, laboratory results,surgical records, postoperative complications, and so on. After being discharged from thehospital, all cells received regular follow-up by phone or clinic recheck which was closedon September26,2010. The content included overall survival (OS), progression-freesurvival (PFS), adjuvant therapy and so on. On the other, surgical specimens obtained from89patients with PDAC were immunohistochemically assessed for DLL4and vascularendothelial growth factor receptor2(VEGFR-2) levels. Prognostic signifcance of DLL4expression was evaluated by Kaplan–Meier method and Cox proportional hazards modelswith backward step wise selection. The correlations of DLL4expression with VEGFR-2expression, tumor stage, and lymph node metastasis were examined by chi-square test andmultivariate logistic regression. We performed all statistical analyses by using SPSS,version18.0.RESULTS: During the study period,89eligible patients received regular follow-up.Their median age (minimum, maximum) was58years (35years,78years), and61.8%were men. The median follow-up time was12months (range,2–49months), and21patients (23.6%) were censored. Those patients who died within30days after surgery wereexcluded from the survival analyses. The median OS and PFS of82patients were12months (95%confdence interval [CI],10.2–13.8months) and6months (95%CI,4.3–7.7months), respectively. High DLL4expression and high VEGFR-2expression wereobserved in38(42.7%) and64(71.9%) patients, respectively.(1) Prognostic Signifcance of DLL4ExpressionIn univariate survival analyses, both OS and PFS were associated with DLL4expression, VEGFR-2expression, CA19-9, PLR, history of diabetes mellitus, resection margin status, tumor size, tumor stage, tumor differentiation, postoperative chemotherapy,postoperative radiotherapy, and postoperative complication (P<0.25). Kaplan–Meier curvesshowed that patients with low DLL4or VEGFR-2expression had a signifcantly bettersurvival than those with high DLL4or VEGFR-2expression, respectively (P<0.05).Patients with low DLL4but high VEGFR-2expression behave like those with low DLL4and low VEGFR-2expression and had better prognosis than those with high DLL4andhigh VEGFR-2expression (P<0.001).In multivariate survival analyses, high DLL4expression, R1resection, nopostoperative radiotherapy, and postoperative complication were shown to be poorindependent prognostic factors for both OS and PFS (P<0.05).(2) Correlations between DLL4Expression and Clinicopathological FeaturesDLL4expression was signifcantly correlated with clinicopathological factors,including VEGFR-2expression, tumor size, tumor stage, local invasion, lymph nodemetastasis, distant metastasis, and disease recurrence (P<0.05).(3) Relationship between DLL4Expression and Tumor StageIn univariate analysis, fve variables, including DLL4expression, VEGFR-2expression, PLR, NLR, and tumor site, were associated with tumor stage (P<0.25).In the multivariate logistic regression model, high DLL4expression and low PLRwere shown to be signifcantly and independently associated with advanced tumor stage(P<0.01).(4) Relationship between DLL4Expression and Lymph Node MetastasisUnivariate analysis showed that lymph node metastasis was associated with sex,DLL4expression, VEGFR-2expression, history of diabetes mellitus, and biochemicalindex (P<0.25).In the multivariate logistic regression model, high DLL4expression and high score ofbiochemical index were shown to be signifcantly and independently associated withlymph node metastasis (P<0.05).CONCLUSION: High DLL4expression is signifcantly associated with poorprognosis for surgically resected PDAC, advanced tumor stage, and lymph node metastasis.Application of adjuvant therapy targeting DLL4-Notch signaling may improve prognosisfor patients with PDAC.2. A study of the relationship between levels of YKL-40and MMP-9in cancertissue and prognosis for patients with pancreatic cancer OBJECTIVE: To evaluate whether high YKL-40expression or high MMP-9expression is associated with poor prognosis after curative resection for pancreatic ductaladenocarcinoma (PDAC) respectively and assess the relationship between YKL-40expression and tumor stage or lymph node metastasis for patients with PDAC.METHODS: The project was managed by ambispective cohort study statisticalmethod. From January1,2005, to December31,2009, the consecutive patients with aconfrmed histologic diagnosis of primary PDAC aged18years or older, who underwentmacroscopically curative resection in Changhai Hospital, were recruited in this study. Allmembers had no history of adjuvant therapy before operation. We reviewed all valuablemedical information during their hospitalization, which consisted of demologycharacteristics, private habits, medical history, clinical manifestation, laboratory results,surgical records, postoperative complications, and so on. After being discharged from thehospital, all patients received regular follow-up by phone or clinic recheck which wasclosed on December31,2011. The content included overall survival (OS), progression-freesurvival (PFS), adjuvant therapy and so on. For another, surgical specimens obtained from229patients with PDAC were immunohistochemically assessed for YKL-40, DLL4andmatrix metalloproteinase9(MMP-9) levels. Prognostic signifcance of YKL-40, DLL4andMMP-9expression were evaluated by Kaplan–Meier method and Cox regression. Thecorrelations of YKL-40expression with tumor stage, and lymph node metastasis wereexamined by chi-square test and multivariate logistic regression. We performed allstatistical analyses by using SPSS, version18.0.RESULT:229eligible patients completed their follow-up reports at the endpoint.Their median age (minimum, maximum) was59years (35years,81years), and62.0%were men. The median follow-up time was11months (range,2-51months), and8patients(3.5%) were censored. The median OS and PFS of eligible patients were11months (95%confdence interval [CI],10.1–11.9months) and6months (95%CI,5.2–6.8months),respectively. High DLL4expression, high MMP-9expression and high DLL4expressionwere observed in156(68.1%),152(66.4%) and139(60.7%) patients, respectively.(1) Prognostic Signifcance of YKL-40ExpressionIn univariate survival analyses, OS was associated with YKL-40expression, MMP-9expression, DLL4expression, CA19-9, CEA, resection margin status, tumor size, tumorstage, tumor differentiation, postoperative chemotherapy, postoperative radiotherapy, andsex (P<0.20). PFS was associated with YKL-40expression, MMP-9expression, DLL4 expression, CA19-9, CEA, resection margin status, tumor size, tumor stage, postoperativechemotherapy, postoperative radiotherapy, postoperative complication and sex (P<0.20).In multivariate survival analyses, OS was significantly correlated with YKL-40expression, DLL4expression, CEA, tumor size, tumor stage, tumor differentiation andpostoperative radiotherapy (P<0.05). And PFS was significantly correlated with YKL-40expression, CEA, resection margin status, tumor stage, postoperative radiotherapy andpostoperative complication (P<0.01).(2) Relationship between DLL4Expression and Tumor StageIn univariate analysis, eight variables, including YKL-40expression, MMP-9expression, DLL4expression, tumor size, tumor site, biochemical index, PLR and NLRwere associated with tumor stage (P<0.20).In the multivariate logistic regression model, tumor size and tumor site were shown tobe signifcantly and independently associated with tumor stage (P<0.05).(3) Relationship between DLL4Expression and Lymph Node MetastasisUnivariate analysis showed that lymph node status was associated with YKL-40expression, MMP-9expression, DLL4expression, CA19-9, tumor size and tumor site(P<0.20).In the multivariate logistic regression model, YKL-40expression and tumor site wereshown to be signifcantly and independently associated with lymph node status (P<0.01).CONCLUSION: High YKL-40expression is signifcantly associated with lymphnode metastasis and poor prognosis for surgically resected PDAC. Application of adjuvanttherapy targeting YKL-40may improve prognosis for patients with PDAC. Meanwhile, thecorrelations of survival with MMP-9and DLL4levels suggest that those two proteins mayact in the process of tumor aggravation.