Expressions of matrix metalloproteinase-7 and -9 and their prognostic significances in rectal cancer

Effects of radiation on the metastatic process

Radiotherapy remains one of the corner stones in the treatment of various malignancies and often leads to an improvement in overall survival. Nonetheless, pre-clinical evidence indicates that radiation can entail pro-metastatic effects via multiple pathways. Via direct actions on cancer cells and indirect actions on the tumor microenvironment, radiation has the potential to enhance epithelial-to-mesenchymal transition, invasion, migration, angiogenesis and metastasis. However, the data remains ambiguous and clinical observations that unequivocally prove these findings are lacking. In this review we discuss the pre-clinical and clinical data on the local and systemic effect of irradiation on the metastatic process with an emphasis on the molecular pathways involved.

Prognostic significance of MMP-7 expression in colorectal cancer: a meta-analysis

OBJECTIVE

Matrix metalloproteinase-7 (MMP-7) is a member of the family of matrix metalloproteinases (MMPs); it is associated with invasive tumor growth and distant metastasis in colorectal cancer (CRC). However, the prognostic value of MMP-7 in CRC remains controversial. Thus, we conducted a meta-analysis to investigate the prognostic value of MMP-7 expression in CRC.

METHODS

We systematically searched for studies evaluating the relationship between MMP-7 expression and the outcome of CRC patients in PubMed, the Cochrane library, Embase, Google Scholar, and Wanfang databases updated to August 2014. Studies were assessed for quality using REMARK (REporting recommendations for tumor MARKer prognostic studies). Hazard ratios (HRs) with 95% confidence intervals (95%CIs) were pooled to estimate the hazard for overall survival (OS) and disease-free survival (DFS), and odds ratios (ORs) with 95%CIs were pooled to estimate the impact of MMP-7 on the 5-year survival rate.

RESULTS

In total, 2985 patients from 17 studies were included in this meta-analysis. Our results showed that MMP-7 over-expression predicted poor OS (HR=3.57, 95%CI 2.21-5.75, P=0.000, random-effect model), poor DFS (HR=2.49, 95%CI 1.73-3.57, P=0.000, fixed-effect model), and decreased 5-year survival rate (OR=0.26, 95%CI 0.19-0.37, P=0.000, fixed-effect model). Therefore, MMP-7 is an indicator of poor survival and high recurrence rate in CRC patients.

CONCLUSION

MMP-7 can serve as a prognostic indicator and a potential novel target for treatment in CRC patients. More well-designed prospective studies with better methodology for MMP-7 assessment are required to clarify the prognostic significance of MMP-7 expression in CRC patients.

Matrix metalloproteinase 9 expression and prognosis in colorectal cancer: a meta-analysis. Tumour Biol. 2013;34:735-741. [PMID: 23269605 DOI: 10.1007/s13277-012-0601-2]

Matrix metalloproteinase-9 (MMP-9) is an important member of the matrix metalloproteinase family and is considered to be involved in the invasion and metastasis of cancer cells. Many studies were published to assess the prognostic role of MMP-9 overexpression in patients with colorectal cancer, but the findings from those studies were inconsistent. We searched eligible studies in Pubmed, Embase, and Web of Science databases. Thirteen studies with a total of 2, 390 CRC patients were finally included into the meta-analysis. The pooled hazard ratios (HRs) with the corresponding 95 % confidence interval (95 % CIs) for overall and progression-free survival were calculated by using meta-analysis. There were nine studies with a total of 1,674 colorectal cancer patients relating the progression-free survival, and eight studies with a total of 1,379 colorectal cancer patients relating the overall survival. Overall, MMP-9 overexpression was associated with poorer progression-free survival in patients with colorectal cancer (fixed-effects HR 1.81, 95 % CI 1.48-2.20, P < 0.001; random-effects HR 1.92, 95 % CI 1.46-2.53, P < 0.001). In addition, MMP-9 overexpression was also associated with poorer overall survival in patients with colorectal cancer (fixed-effects HR 1.74, 95 % CI 1.39-2.19, P < 0.001; random-effects HR 1.78, 95 % CI 1.31-2.41, P < 0.001). MMP-9 expression is associated with the prognosis of patients with colorectal cancer, and patients with higher MMP-9 expression have poorer survival.