Abstract 855: Analysis of canonical uveal melanoma mutations reveals novel signaling effects

Uveal Melanoma (UM) is the most common primary ocular cancer in adults. Virtually all UM have activating mutations in the Gq signaling pathway. Metastatic risk in patients correlates with additional secondary mutations, where the lowest metastatic risk (class 1) is associated with EIF1AX and SF3B1, and the highest metastatic risk (class 2) is associated with BAP1 mutations. The interplay between the initiating Gq pathway mutations, and the secondary mutations found in all UM has not been well understood yet. Here, we utilize a multi-omics approach, to describe gene expression changes, the proteome, and phosphatome, following GNAQ mutation and BAP1 knockout in primary human uveal melanocytes. We generated human uveal melanocyte cell lines with inducible and specific mutations and analyzed via RNAseq, ATACseq, and mass spectrometry. Results reveal significant changes in pathways related to p53, chromatin regulation/modification, gene expression, and RNA processing with noted dysregulation of genes JUN, HDAC4, YAP, and SOX10, which cause senescence in melanocytes following GNAQ mutation, and are relieved through additional mutation in BAP1.

Citation Format: Dawn Alexandra Owens, Stefan Kurtenbach, Jeffim N. Kuznetsoff, Daniel A. Rodriguez, Anthony Cruz, J. Harbour. Analysis of canonical uveal melanoma mutations reveals novel signaling effects [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 855.

Agronomic Factors Associated with Bacterial Leaf Streak Development Caused by Xanthomonas vasicola pv. vasculorum in Corn

In 2016, the bacterium Xanthomonas vasicola pv. vasculorum was reported causing bacterial leaf streak on Nebraska corn. Prior to this report, the pathogen was reported on corn only in South Africa. Hence, there was a lack of information about the effects of corn production practices on bacterial leaf streak development. A survey of growers, crop consultants, extension agents, and others in the field of agriculture was initiated during the 2016 and 2017 corn growing seasons to examine agronomic factors that may affect the disease. Survey respondents were asked to submit a symptomatic leaf sample for pathogen confirmation via polymerase chain reaction, along with a completed survey on corn production practices. Analyses of 325 survey responses via random forest analysis indicated that irrigation, planting date, and crop rotation were the three most important predictors of corn samples testing positive for X. vasicola pv. vasculorum. According to a classification and regression tree analysis, irrigation use, the V7-R2 range of crop stages, multiple years of corn in a crop rotation or a corn-sorghum rotation, and planting dates after 2 May, were most closely associated with corn samples testing positive for X. vasicola pv. vasculorum. χ² tests of independence indicated that applications of nitrogen fertilizer and glyphosate herbicide use may also be related to bacterial leaf streak development.

Alternative Hosts in the Families Poaceae and Cyperaceae for Xanthomonas vasicola pv. vasculorum, Causal Agent of Bacterial Leaf Streak of Corn

The bacterial pathogen Xanthomonas vasicola pv. vasculorum was first reported in the United States causing bacterial leaf streak on Nebraska corn (Zea mays) in 2016. The bacterium is also known to cause disease in sugarcane, grain sorghum, broom bamboo, and various palm species. The objective of this study was to identify alternative hosts for X. vasicola pv. vasculorum among plants commonly found in corn growing areas of the United States. In repeated greenhouse experiments, 53 species of plants found in the United States that had not been tested previously for susceptibility to X. vasicola pv. vasculorum were inoculated with the pathogen and monitored for symptom development. Eleven species in the family Poaceae exhibited symptoms: oat (Avena sativa), rice (Oryza sativa), orchardgrass (Dactylis glomerata), indiangrass (Sorghastrum nutans), big bluestem (Andropogon gerardii), little bluestem (Schizachyrium scoparium), timothy (Phleum pratense), sand bluestem (Andropogon hallii), green foxtail (Setaria viridis), bristly foxtail (Setaria verticillata), and johnsongrass (Sorghum halepense). Yellow nutsedge (Cyperus esculentus) in the Cyperaceae also was a symptomatic host. In addition, endophytic colonization by X. vasicola pv. vasculorum was found in three asymptomatic alternative hosts: downy brome (Bromus tectorum), tall fescue (Festuca arundinacea), and western wheatgrass (Pascopyum smithii). Experiments were also conducted in the field to determine the potential for alternative hosts to become infected by natural inoculum. Symptoms developed only in big bluestem and bristly foxtail in field experiments. These results suggest that infection of alternative hosts by X. vasicola pv. vasculorum can occur, but infection rates might be limited by environmental conditions.

Comparison of enhanced chemiluminescence and microparticle enzyme immunoassay for the measurement of hepatitis B surface antibody

Two commercially available immunoassays for the quantitative measurement of antibodies to hepatitis B surface antigen (HBsAg) were compared. The Amerlite enhanced chemiluminescence assay (ECL), which utilizes capture antigen obtained from HBsAg-positive donors bound to microtitre wells, was compared with the Abbott Laboratories microparticle enzyme immunoassay (IMx), which uses a recombinant antigen coated on to microparticle carriers. A total of 310 specimens, 116 from naturally infected patients (group A), 93 from patients vaccinated with a human plasma-derived vaccine (group B) and 101 patients vaccinated with a recombinant vaccine (group C), were tested in both assays undiluted and diluted 1:11. Samples that showed discordant results were also tested in a conventional quantitative enzyme immunoassay (Sorin). The results show significant differences in the level of anti-HBsAg in patient sera using the two technologies. In general, IMx gave significantly higher values than ECL for all three patient categories tested. These differences may lead to conflicting reports being issued by laboratories who change their assay system or when a sample from one patient is tested by different laboratories using different assays.

Comparison of ELISA with virus isolation for the diagnosis of genital herpes

An enzyme linked immunosorbent assay (ELISA) system which detects and simultaneously types herpes simplex virus antigens in clinical specimens from patients with genital herpes has been compared with standard tissue culture isolation. Although more sensitive than a similar method previously described and also more sensitive than electron microscopy and immunofluorescence, ELISA did not detect all the viruses isolated in tissue culture. Costs were comparable. The speed of obtaining the result together with knowledge of the type causing infection are useful when antiviral chemotherapy is envisaged and when considering the likelihood of recurrences.

Comparison of a commercial ELISA system with restriction endonuclease analysis for typing herpes simplex virus

Isolates of herpes simplex virus which had previously been typed by restriction enzyme analysis were typed again with a commercial ELISA system using polyclonal antibodies. There was complete correlation between the two techniques. Although restriction is more precise and definitive, when typing only is required the simplicity of ELISA makes it the preferred technique.

Comparison of the continuous cell line 293 with human embryo kidney cells and human embryo fibroblast cells for the cultivation of ocular viruses

The continuous cell line 293 was evaluated as a replacement for primary human embryo kidney (HEK) cells in the cultivation of ocular viruses. The 293 cells were found to be as sensitive as HEK cells and human embryo fibroblast (HEF) cells for the cultivation of adenoviruses and herpes simplex virus (HSV) respectively. As a continuous cell line, 293 cells are preferable to HEK and HEF cells for the routine isolation of ophthalmic viruses.

Acute epiglottitis in adults

Fourteen cases of adult acute epiglottitis with their clinical manifestations are presented. The history, etiology, pathophysiology, and diagnosis of the disease are reviewed. The controversies of management are discussed and a concise management protocol is outlined.

Successful therapy of an ACTH-producing gastric carcinoid APUD tumor: report of a case and review of the literature

A case of a patient with a metastatic ACTH (adrenocorticotrophic hormone)-producing gastric carcinoid APUD (amine precursor uptake and decarboxylation) tumor is presented. The patient presented with Cushing's syndrome and very high levels of ACTH. The Cushing's syndrome was controlled medically, and when the patient deteriorated clinically she received treatment with a combination of BCNU, adriamycin, and ftorafur. She responded dramatically with marked clinical improvement and normalization of plasma ACTH levels. The current status of the APUD cell concept is discussed, with its overall implications for treatment of this group of malignancies.

Excretion of faecal viruses during the first year of life

Four hundred faecal samples, collected at approximately weekly intervals during the first year of life from nine babies, were examined for the presence of viruses. Only nine (2.3%) samples contained a virus detectable by electron microscopy, and on all but one occasion only one type of virus was present and that in small numbers. Thirty (7.5%) of the specimens contained an enterovirus other than poliovirus, and these represetned 10 infections in four of the children. All three types of poliovirus, probably vaccine derived, were excreted by each child, and one or more types were present in 87 (21.8%) of the samples. There was no evidence to suggest that any of the illnesses suffered by the children had been caused by faecal viruses. Infection with these viruses was uncommon in the first three months of life but more than 40% of faecal samples obtained from children between the ages of 3 months and 1 year contained a faecal virus.