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Weber, J. D.

Publications and source records attributed to Weber, J. D..

2 recordsLinked to original sources

ARF suppresses 5'-terminal oligopyrimidine mRNA translation

Tumor cells require nominal increases in protein synthesis in order to maintain high proliferation rates. As such, tumor cells must acquire enhanced ribosome production. How many of the mutations in tumor cells ultimately achieve this aberrant production is largely unknown. The gene encoding ARF is the most commonly deleted gene in human cancer. ARF plays a significant role in regulating ribosomal RNA synthesis and processing, ribosome export into the cytoplasm, and global protein synthesis. Utilizing ribosome profiling, we show that ARF is a major suppressor of 5-terminal oligopyrimidine mRNA translation. Genes with increased translational efficiency following loss of ARF include many ribosomal proteins and translation factors. Knockout of p53 caused a similar increase in 5-TOP mRNA translation. The 5-TOP regulators mTORC1, eIF4G1 and LARP1 are dysregulated in ARF and p53 null cells.

cell biology

ADAR1 editing dependency in triple-negative breast cancer

Triple-negative breast cancer (TNBC) is the deadliest form of breast cancer. Unlike other types of breast cancer that can be effectively treated by targeted therapies, no such targeted therapy exists for all TNBC patients. The ADAR1 enzyme carries out A-to-I editing of RNA to prevent sensing of cellular double-stranded RNAs (dsRNA). ADAR1 is highly expressed in breast cancer including TNBC. Here, we demonstrate that ADAR1 expression and editing activity is required in TNBC cell lines but not in ER+ and/or Her2+ cells. In TNBC cells, knockdown of ADAR1 attenuates proliferation and tumorigenesis. PKR expression is elevated in TNBC and its activity is induced upon ADAR1-knockdown, which correlates with a decrease in translation. ADAR1-dependent TNBC cell lines also exhibit elevated IFN stimulated gene expression. IFNAR1 reduction significantly rescues the proliferative defects of ADAR1 loss. These findings establish ADAR1 as a novel therapeutic target for TNBC tumors.

cancer biology