Effects Of Tissue Inhibitor Of Metalloproteinase-1 Combined With Matrix Metalloproteinase-7、Matrix Metalloproteinase-9 Expressions On Prognostic Evaluation Of Gastric Cancer

Gastric cancer（GC）is the fifth most common malignant tumour and third leading cause of cancer death worldwide.Despite advances in the diagnosis and treatment of gastrointestinal cancer in recent decades,the prognosis for gastric cancer patients is still poor,with a 5-year survival rate of 35.9%.Invasion and metastasis account for most patients mortality related to solid tumours,which indicated that identifying invasion and metastasis-associated prognostic markers is greatly significant to improve the well-targeted treatment,extend survival and quality of life in GC patients.The proteolytic degradation of the extracellular matrix（ECM）is an essential step in tumour invasion and metastasis.This degradation is mainly dependent on the activities of both matrix metalloproteinases（MMPs）and tissue inhibitors of metalloproteinases（TIMPs）.Among all the TIMPs members,tissue inhibitor of metalloproteinase-1（TIMP-1）not only can degrade the extracellular matrix,but also can be independent of MMPs in its roles in tumorigenesis and progression,which has been recognized as a promising prognostic biomarker.Previous studies have showed that the balance and changes of TIMP-1 combined with MMP-7 and MMP-9expressions may play more important role in tumorigenesis and prognosis compared with the expression of MMPs or TIMPs alone,therefore,co-expression of TIMP-1、MMP-7 and MMP-9 could serve as more promising prognostic biomarkers and guide clinical practice and explain the variability of survival.Objectives:The study conducts a meta-analysis restricted to gastrointestinal cancer to quantitatively appraise the prognostic value of TIMP-1 expression and reach a conclusion about the association between TIMP-1 and the survival of gastrointestinal cancer patients with different clinical characteristics.Furthermore,The GC cohort study in China focused on the prognostic value of TIMP-1 expression,matrix metalloproteinase-7（MMP-7）expression,and matrix metalloproteinase-9（MMP-9）expression alone or in combination.The study aimed to provide epidemiological evidences for screening and identificating the biomarkers associated with the prognosis of GC patients.Methods:（1）Meta Analysis:Pub Med,Cochrane Library and Embase databases were electronically searched for literatures which detected TIMP-1 expression in gastrointestinal cancer tissues by immunohistochemistry（IHC）and enzyme-linked immunosorbent assay（ELISA）,and analyzed the relationship between TIMP-1expression and clinicopathological features and prognosis of gastrointestinal cancer patients.The search time was from the establishment of the database to March 2020.According to the inclusion and exclusion criteria,literatures were screened and data were extracted.The quality of the included studies was evaluated by Newcastle Ottawa scale（NOS）.Stata 12.0 software was used to analyze the correlation between TIMP-1expression and clinicopathological features and prognosis.The final effect indicators were odds ratio（OR）and its 95%confidence interval（CI）,risk ratio（HR）and its 95%CI.（2）Prospective Cohort Study:A total of 273 GC patients who received radical gastrectomy with negative surgical margin and no distant metastasis were included in this study from 2010 to 2020.The follow-up of the patients was conducted after the surgery at 3 months,6 months,1 year and every 1 year until the death of the patients or lost to follow-up.The MMP-7、MMP-9 and TIMP-1 expressions were evaluated through immunohistochemistry（IHC）.c~2 test or Fisher exact test was used to analyze the relationship between MMP-7、MMP-9 and TIMP-1 expressions and clinicopathological features.Kaplan Meier method was used to draw the survival curves,and Log rank test was used to compare whether the survival curve was statistically different.Multivariate Cox regression model was used to analyze the prognostic value of the expression of MMP-7、MMP-9 and TIMP-1 alone or in combination for GC patients,and to calculate HR and 95%CI.Results:（1）Meta Analysis:A total of 3958 patients from twenty-two studies were included in the meta-analysis.Elevated TIMP-1 levels were significantly associated with poor survival in gastrointestinal cancer（TIMP-1-IHC staining:HR=2.04,95%CI:1.59-2.61,I~2=35.7%,P_Q=0.16;pretreatment serum/plasma TIMP-1 levels:HR=2.02,95%CI:1.80-2.28,I~2=0%,P_Q=0.63）.Moreover,clinicopathological parameter data analysis showed that elevated TIMP-1 levels were significantly associated with lymph node metastasis（N1/N2/N3 vs N0:OR=2.92,95%CI:1.95-4.38）and higher TNM stages（III/IV vs I/II:OR=2.73,95%CI:1.23-6.04）.（2）Prospective Cohort Study:A total of 273 subjects were included in the survival analysis.The average age was 63.26±10.33 years old,including 208 males（76.2%）,228 patients（83.5%）with N1/N2/N3 stage,the median follow-up time was 79.5 months,and the 5-year overall survival（OS）rate was 38%.Univariate analysis results showed that gastric cancer patients with T3/T4 stage,N1/N2/N3 stage,high histological grade,neurofascicular infiltration,vascular infiltration,no postoperative chemotherapy had shorter survival time,differences were of statistical significance（Log rank P<0.05）.Furthermore,gastric cancer patients with MMP-7⁺/TIMP-1⁺and MMP-9^-/TIMP-1⁺expressions exhibited worse survival（Log rank P<0.05）.Multivariate Cox regression analysis models adjusted for the characteristics,including T stage,N stage,age,gender,tumor size,tumor types,histological grade,neurofascicular infiltration,vascular infiltration and chemotherapy.In the expression pattern of MMP-7 and TIMP-1,patients with MMP-7⁺/TIMP-1⁺had a significantly increased risk of death compared with patients with other patterns of expression（HR=1.583,95%CI:1.001-2.504）.In the expression pattern of MMP-9 and TIMP-1,patients with MMP-9^-/TIMP-1⁺had a significantly increased risk of death compared with patients with other patterns of expression（HR=1.712,95%CI:1.186-2.471）.Furthermore,N1/N2/N3 stage,neurofascicular infiltration and non-chemotherapy could be the independent poor prognostic factors for GC patients.Conclusions:Both TIMP-1-positive IHC staining and high serum/plasma TIMP-1 levels were poor prognostic factors for the survival of gastrointestinal cancer patients.In GC patients without distant metastasis,no association was found between the expressions of TIMP-1,MMP-7,MMP-9 and the survival of GC patients.When analyzed jointly,MMP-7⁺/TIMP-1⁺expression and MMP-9^-/TIMP-1⁺expression could be the independent poor prognostic factors for gastric cancer patients.