Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2021
Erindi/veggspjald / Talk/poster E79
Höfundar / Authors: Arsalan Amirfallah, Hildur Knútsdóttir, Aðalgeir Arason, Bylgja Hilmarsdóttir, Óskar Þór Jóhannsson, Bjarni A. Agnarsson, Rósa B. Barkardóttir, Inga Reynisdóttir
Starfsvettvangur / Affiliations: Landspítali
Kynnir / Presenter: Inga Reynisdóttir
Breast cancer (BC) is the cancer most often diagnosed in women. MIR21 has been shown to be an oncomiR in BC. Most of the effects of miR21 have been attributed to miR21-5p rather than the less studied miR21-3p. The aim of the study was to analyze whether expression of miR21-3p is prognostic for BC. MiR-21-3p association with survival, clinical and pathological characteristics was analyzed in four BC cohorts. Analytical tools were also used to infer miR21-3p function and to identify potential target genes and functional pathways. High miR21-3p levels associated with characteristics that predicted worse prognosis. Specifically, in METABRIC (n=1174), high miR21-3p levels associated with large tumors, high grade, lymph node and HER2 positivity, and shorter breast-cancer-specific survival (HR=1.38, CI 1.13-1.68). This association remained significant after adjusting for confounding factors. The genes with expression levels that correlated with miR21-3p were enriched in pathways such as epithelial-to-mesenchymal transition and proliferation. Among the most significantly downregulated targets were the tumor suppressive genes STARD13 and ZNF132. The results from this study emphasize that both 3p- and 5p-arms from a MIR warrant independent study. The results suggest miR21-3p as a potential biomarker as miR21-3p overexpression in breast tumors predicted worse BC progression and its expression affected genes in pathways that drive BC by down-regulating tumor suppressor genes.