Nuclear receptor binding protein 1 (NRBP1) is a highly conserved
protein that is ubiquitously expressed across cell types in humans. NRBP1 has been recently identified as an adaptor
protein. It has been suggested that it plays important roles in cellular homeostasis and the pathophysiology of
cancer. To determine whether NRBP1 is involved in the pathophysiology of
breast cancer, we performed a correlation study between the expression level of NRBP1 and the clinicopathological features in 92
breast cancer patients. A strong correlation was detected between NRBP1 expression and advanced histopathology grades,
tumor, node, and
metastasis stage,
tumor diameter, lymph node involvement, as well as the recurrence of
breast cancer in 92 tested patients. The
tumor tissues from patients also expressed lower NRBP1 than did adjacent healthy tissues. Furthermore, we overexpressed NRBP1 in MCF-7 and MDA-MB-231
breast cancer cell lines and found NRBP1 upregulation-inhibited cell proliferation by using
3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Blocking the autocrine Wnt signaling pathway by
LGK974 could remove the NRBP1-overexpression-induced inhibition in
breast cancer cells. The results of this study suggest that NRBP1 plays a
tumor-suppressive role in
breast cancer pathophysiology, which likely acts through the Wnt/β-
catenin signaling pathway.