Upregulation of matrix metalloproteinase 14 (MMP14) is associated with poor prognosis in renal clear cell carcinoma-a bioinformatics analysis.

Background: Matrix metalloproteinase 14 (MMP14) has been reported to be upregulated in some types of cancer and to promote cancer cell invasion and metastasis. However, the expression profile and functional role of MMP14 in kidney renal clear cell carcinoma (KIRC) remains unknown. This study investigated the association between MMP14 expression level and prognosis in KIRC.

Methods: The messenger RNA (mRNA) expression profile and clinical data (including T stage, N stage, M stage, pathologic stage, gender, race, age, histologic grade, serum calcium, hemoglobin) were obtained from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) database. Protein expression was evaluated by immunohistochemistry in the Human Protein Atlas (HPA) database. Correlation analyses between MMP14 and all mRNAs in KIRC were batch calculated, and gene set enrichment analyses (GSEA) were then conducted of Disease Ontology (DO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways using R packages. Multivariate logistic regression analysis was used to explore the prognostic factors of KIRC patients.

Results: The gene expression of MMP14 was significantly upregulated in KIRC tissues when compared with the normal tissue (P<0.001). The predictive ability of MMP14 as a variable for predicting tumor and normal outcomes had certain accuracy based on the receiver operating characteristic (ROC) model [area under the curve (AUC) =0.881, confidence interval (CI): 0.844-0.917]. When compared with the normal kidney tissue, the protein expression of MMP14 in KIRC got an increased trend, but due to the limited sample size, the difference is not statistically significant (P>0.05). Survival analysis revealed that MMP14 was significantly associated with overall survival in KIRC (P=0.013). GSEA of DO terms indicated high expression of MMP14 was related to KIRC, and GSEA of KEGG pathways showed that MMP14 and its coexpressed genes were significantly positively correlated with pathways in cancer. Signaling pathway GSEA indicated the upregulation of MMP14 in KIRC may activate cancer pathways.

Conclusions: MMP14 may be associated with poor prognosis in KIRC and may be a potential prognostic marker for KIRC.