Dataset Information

FUN14 domain-containing 1 promotes breast cancer proliferation and migration by activating calcium-NFATC1-BMI1 axis.

ABSTRACT:

Background

FUN14 domain-containing 1 (FUNDC1), as a novel member of mitochondria-associated endoplasmic reticulum (ER) membranes associates with mitochondrial division and mitophagy. However, the expression profile and functional roles of FUNDC1 remain largely unclear in human cancer biology, including breast cancer (BC).

Methods

Immunohistochemistry and western blot analysis were used to determine the expression of FUNDC1 and BMI1 polycomb ring finger oncogene (BMI1). CCK8, cell counting and transwell assays were used to analyze cell proliferation, migration and invasion, respectively. Luciferase reporter and chromatin immunoprecipitation (ChIP) assays were used to detect the transcriptional regulation of Nuclear factor of activated T-cells, cytoplasmic 1 (NFATC1). The prognostic merit of NFATC1 expression was assessed by Kaplan-Meier assay.

Findings

Immunohistochemistry revealed strong immunostaining for FUNDC1 in cytoplasmic and nuclear membrane distribution in BC tissues as compared with normal breast epithelium. Kaplan-Meier survival analysis showed worse outcome for BC patients with high FUNDC1 expression. In vitro assay of gain- and loss-of-function of FUNDC1 suggested that FUNDC1 could stimulate BC cell proliferation, migration and invasion. Furthermore, elevated FUNDC1 level promoted Ca²⁺ cytosol influx from ER and extracellular, as well as NFATC1 nuclear translocation and activity. Nuclear NFATC1 bound to the BMI1 gene promoter and transcriptionally upregulated its expression. Notably, BMI1 overexpression could rescue the loss of function of FUNDC1. Co-expression of FUNDC1 and BMI1 in BC patients predicted worse prognosis than without either expression.

Interpretation

FUNDC1 might promote BC progression by activating the Ca²⁺-NFATC1-BMI1 axis. This pathway may be promising for developing multiple targets for BC therapy.

SUBMITTER: Wu L

PROVIDER: S-EPMC6442990 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:Purpose:Evidence describing TMED3 in the context of breast cancer is scarce, and the effect of TMED3 on Wnt/?-catenin signaling in breast cancer has not been reported. The objective of this study was to determine the potential physiological functions and molecular mechanisms of TMED3 in breast cancer. Materials and Methods:Quantitative real-time PCR and Western blot analysis were used to analyze the expression of TMED3 mRNA and protein in 182 paraffin-embedded primary breast cancer tissues and 60 paired noncancerous tissues and 25 fresh primary breast cancer tissues and surrounding adjacent noncancerous tissues. Associations between TMED3 expression and clinicopathologic factors or overall survival were determined. The effects of overexpression or knockdown of TMED3 on proliferation, migration, invasion, and cell cycle progression in breast cancer cell lines were investigated with the Cell Counting Kit-8, clone formation assay, transwell assay, wound healing assay, and flow cytometry, respectively. Immunofluorescence and Western blot analysis were used to detect the expression of cell cycle, migration-related, and Wnt/?-catenin signaling proteins. Results:The expression of TMED3 mRNA and protein were significantly increased in breast cancer tissues and cell lines compared to normal controls. TMED3 upregulation was significantly correlated with clinicopathologic characteristics and predicted poor prognosis in patients with breast cancer. TMED3 overexpression promoted proliferation, migration, invasion, and cell cycle progression compared to controls in breast cancer cell lines. TMED3 knockdown suppressed proliferation, migration, invasion, and cell cycle progression compared to controls in breast cancer cell lines. TMED3 promoted proliferation and migration of breast cancer cells by a mechanism that involved Wnt/?-catenin signaling. Conclusion:TMED3 behaves as an oncogene that promotes the proliferation and migration of breast cancer cells by a mechanism that involved Wnt/?-catenin signaling. Strategies targeting TMED3 have potential therapeutic implications for patients with breast cancer.