Prognostic value of TERF1 expression in prostate cancer

Abstract

Background Telomere dysfunction is one of the hallmarks of cancer and is crucial to prostate carcinogenesis. TERF1 is a gene essential to telomere maintenance, and its dysfunction has already been associates with several cancers. TERF1 is a target of miR-155, and this microRNA can inhibit its expression and promotes carcinogenesis in breast cancer. We aim to analyze TERF1, in gene and mRNA level, involvement in prostate cancer progression. Results Alterations in TERF1 DNA were evaluated using datasets of primary tumor and castration-resistant tumors (CRPC) deposited in cBioportal. The expression of TERF1 mRNA levels was assessed utilizing TCGA datasets, clinical specimens, and metastatic prostate cancer cell lines (LNCaP, DU145, and PC3). Six percent of localized prostate cancer presents alterations in TERF1 (the majority of that was amplifications). In the CRPC cohort, 26% of samples had TERF1 amplification. Patients with TERF1 alterations had the worst overall survival only on localized cancer cohort (p = 0.0027). In the TCGA cohort, mRNA levels of TERF1 were downregulated in comparison with normal tissue (p = 0.0013) and upregulated in tumors that invade lymph nodes (p = 0.0059). The upregulation of TERF1 is also associated with worst overall survival (p = 0.0028) and disease-free survival (p = 0.0023). There is a positive correlation between TERF1 and androgen receptor expression in cancer tissue (r = 0.53, p < 0.00001) but not on normal tissue (r = − 0.16, p = 0.12). In the clinical specimens, there is no detectable expression of TERF1 and upregulation of miR-155 (p = 0.0348). In cell lines, TERF1 expression was higher in LNCaP and was progressively lower in DU145 and PC3 (p = 0.0327) with no differences in miR-155 expression. Conclusion Amplification/upregulation of TERF1 was associated with the worst prognostic in localized prostate cancer. Our results corroborate that miR-155 regulates TERF1 expression in prostate cancer. TERF1 has the potential to become a biomarker in prostate cancer.

MicroRNAs: a crossroad that connects obesity to immunity and aging

“…Studies have reported that the TP53 gene was targeted by miR-125b and miR-504 in various cell lines [ 177 , 178 ]. Specifically, miR-155 targets the telomere repeat-binding factor 1 (trf1) gene, which is a component of the protein responsible for telomere maintenance [ 179 , 180 ]. Another report has shown that miR-155 is mostly downregulated in vascular aging and restoration of miR-155 rescues the phenotype related to vascular aging [ 181 ].…”