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PurposeHow herpes simplex virus (HSV) is transported from the infected neuron cell body to the axon terminal is poorly understood. Several viral proteins are candidates for regulating the process, but the evidence is controversial. We compared the results of Us9 deletions in two HSV strains (F and NS) using a novel quantitative assay to test the hypothesis that the viral protein Us9 regulates the delivery of viral DNA to the distal axon of retinal ganglion cells in vivo. We also deleted a nine-amino acid motif in the Us9 protein of F strain (Us9-30) to define the role of this domain in DNA delivery.MethodsThe vitreous chambers of murine eyes were infected with equivalent amounts of F or NS strains of HSV. At 3, 4, or 5 days post infection (dpi), both optic tracts (OT) were dissected and viral genome was quantified by qPCR.ResultsAt 3 dpi, the F strain Us9- and Us9-30 mutants delivered less than 10% and 1%, respectively, of the viral DNA delivered after infection with the Us9R (control) strain. By 4 and 5 dpi, delivery of viral DNA had only partially recovered. Deletion of Us9 in NS-infected mice has a less obvious effect on delivery of new viral DNA to the distal OT. By 3 dpi the NS Us9-strain delivered 22% of the DNA that was delivered by the NS wt, and by 4 and 5 dpi the amount of Us9-viral DNA was 96% and 81%, respectively.ConclusionsA highly conserved acidic cluster within the Us9 protein plays a critical role for genome transport to the distal axon. The transport is less dependent on Us9 expression in the NS than in the F strain virus. This assay can be used to compare transport efficiency in other neurotropic viral strains.

UnlabelledThe transcription factor ZNF217 is a candidate oncogene in the amplicon on chromosome 20q13 that occurs in 20% to 30% of primary human breast cancers and that correlates with poor prognosis. We show that Znf217 overexpression drives aberrant differentiation and signaling events, promotes increased self-renewal capacity, mesenchymal marker expression, motility, and metastasis, and represses an adult tissue stem cell gene signature downregulated in cancers. By in silico screening, we identified candidate therapeutics that at low concentrations inhibit growth of cancer cells expressing high ZNF217. We show that the nucleoside analogue triciribine inhibits ZNF217-induced tumor growth and chemotherapy resistance and inhibits signaling events [e.g., phospho-AKT, phospho-mitogen-activated protein kinase (MAPK)] in vivo. Our data suggest that ZNF217 is a biomarker of poor prognosis and a therapeutic target in patients with breast cancer and that triciribine may be part of a personalized treatment strategy in patients overexpressing ZNF217. Because ZNF217 is amplified in numerous cancers, these results have implications for other cancers.SignificanceThis study finds that ZNF217 is a poor prognostic indicator and therapeutic target in patients with breast cancer and may be a strong biomarker of triciribine treatment efficacy in patients. Because previous clinical trials for triciribine did not include biomarkers of treatment efficacy, this study provides a rationale for revisiting triciribine in the clinical setting as a therapy for patients with breast cancer who overexpress ZNF217.