Abstract B57: Sucrose nonfermenting 1-related kinase (SNRK) expression and function in ovarian cancer.
Authors: Erin A. Bishop, Stephanie M. Cossette, Ramani Ramchandran
Journal: Clinical Cancer Research (2016)

Abstract Purpose of study: SNRK is a member of the sucrose nonfermenting (SNF)-related kinase family of serine/threonine kinases with sequence similarity to AMP-activated protein kinase (AMPK). AMPK proteins play a central role in cellular energy regulation. Active AMPK restricts cellular proliferation, growth, and metabolic substrate synthesis, and increases ATP-generating processes, such as glucose and fatty acid oxidation. SNKR has been previously shown to regulate metabolism and to suppress adipocyte inflammation via mTORC1, which is a pathway known to be aberrant in ovarian cancer. SNRK has also been shown to reduce colon cancer cell proliferation and stable knockdown of SNRK increases in vitro colon cancer cell tumorigenicity indicating that SNRK is a regulator of cell proliferation. The goal of this study is to describe the expression and function of SNRK in ovarian cancer and benign cell lines. Experimental Procedures: The ovarian cancer cell line A2780 was used as well as the benign surface epithelial cell line, IOSE, for comparison. Quantitative PCR and western blot analysis were used to compare SNRK mRNA and protein expression between cell lines. SNRK was knocked down in each cell line using lentiviral transduction. Proliferation, migration, and invasion assays were performed to determine the effects of SNRK knockdown on tumorigenicity. Alterations in metabolism as a result of SNRK knockdown were assessed using the XF Extracellular Flux Analyzer (Seahorse Bioscience). Western blot analysis was used to determine changes in active phosphorylated AMPK (pAMPK) and mTOR protein expression. Summary of data: IOSE and A2780 cells have similar levels of SNRK mRNA and protein expression. We observed increased proliferation, migration, and invasion in SNRK knockdown cells compared to controls with significant differences seen in the IOSE cells. A2780 and IOSE SNRK knockdown cells have decreased oxygen consumption rates and decreased spare respiratory capacity in the presence of fatty acids as a substrate compared to controls as well as decreased pAMPK and mTOR expression. Conclusions: Our results show that decreased SNRK levels lead to increased tumorigenicity and impairment in fatty acid oxidation particularly in the benign IOSE cells. Along with these functional changes, a decrease in pAMPK expression is also seen. Our results suggest that SNRK plays a role in regulating growth and metabolism and that this regulation appears to be required in benign ovarian cells, while malignant cells may have the ability to control growth independent of SNRK. Citation Format: Erin A. Bishop, Stephanie M. Cossette, Ramani Ramchandran. Sucrose nonfermenting 1-related kinase (SNRK) expression and function in ovarian cancer. [abstract]. In: Proceedings of the AACR Special Conference on Advances in Ovarian Cancer Research: Exploiting Vulnerabilities; Oct 17-20, 2015; Orlando, FL. Philadelphia (PA): AACR; Clin Cancer Res 2016;22(2 Suppl):Abstract nr B57.