Barrington et al. examined the effect of four human diets (American, Mediterranean, Japanese, and Maasai/ketogenic) on metabolic health across four mouse...

ABSTRACT. Fertility traits, such as heifer pregnancy, are economically important in cattle production systems, and are therefore, used in genetic selection programs. The aim of this study was to identify single nucleotide polymorphisms (SNPs) using RNA-sequencing (RNA-Seq) data from ovary, uterus, endometrium, pituitary gland, hypothalamus, liver, longissimus dorsi muscle, and adipose tissue in 62 candidate genes associated with heifer puberty in cattle. RNA-Seq reads were assembled to the bovine reference genome (UMD 3.1.1) and analyzed in five cattle breeds; Brangus, Brahman, Nellore, Angus, and Holstein. Two approaches used the Brangus data for SNP discovery 1) pooling all samples, and 2) within each individual sample. These approaches revealed 1157 SNPs. These were compared with those identified in the pooled samples of the other breeds. Overall, 172 SNPs within 13 genes (CPNE5, FAM19A4, FOXN4, KLF1, LOC777593, MGC157266, NEBL, NRXN3, PEPT-1, PPP3CA, SCG5, TSG101, and TSHR) were concordant in the five breeds. Using Ensembl's Variant Effector Predictor, we determined that 12% of SNPs were in exons (71% synonymous, 29% nonsynonymous), 1% were in untranslated regions (UTRs), 86% were in introns, and 1% were in intergenic regions. Since these SNPs were discovered in RNA, the variants were predicted to be within exons or UTRs. Overall, 160 novel transcripts in 42 candidate genes and five novel genes overlapping five candidate genes were observed. In conclusion, 1157 SNPs were identified in 62 candidate genes associated with puberty in Brangus cattle, of which, 172 were concordant in the five cattle breeds. Novel transcripts and genes were also identified.

ObjectiveThe Collaborative Cross (CC) is a mouse population model with diverse and reproducible genetic backgrounds used to identify novel disease models and genes that contribute to human disease. Since spontaneous tumour susceptibility in CC mice remains unexplored, we assessed tumour incidence and spectrum.DesignWe monitored 293 mice from 18 CC strains for tumour development. Genetic association analysis and RNA sequencing were used to identify susceptibility loci and candidate genes. We analysed genomes of patients with gastric cancer to evaluate the relevance of genes identified in the CC mouse model and measured the expression levels of ISG15 by immunohistochemical staining using a gastric adenocarcinoma tissue microarray. Association of gene expression with overall survival (OS) was assessed by Kaplan-Meier analysis.ResultsCC mice displayed a wide range in the incidence and types of spontaneous tumours. More than 40% of CC036 mice developed gastric tumours within 1 year. Genetic association analysis identified Nfκb1 as a candidate susceptibility gene, while RNA sequencing analysis of non-tumour gastric tissues from CC036 mice showed significantly higher expression of inflammatory response genes. In human gastric cancers, the majority of human orthologues of the 166 mouse genes were preferentially altered by amplification or deletion and were significantly associated with OS. Higher expression of the CC036 inflammatory response gene signature is associated with poor OS. Finally, ISG15 protein is elevated in gastric adenocarcinomas and correlated with shortened patient OS.ConclusionsCC strains exhibit tremendous variation in tumour susceptibility, and we present CC036 as a spontaneous laboratory mouse model for studying human gastric tumourigenesis.

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Introducción: el virus de la Hepatitis E (VHE), transmitido por la ruta fecal-oral, causa enfermedad hepática aguda. En Colombia se han realizado algunos estudios en pacientes con diagnóstico de hepatitis viral, en trabajadores de fincas porcícolas, en población porcina y en muestras ambientales. Objetivo: evaluar la presencia de anticuerpos anti-VHE en muestras de donantes de sangre del municipio de Yarumal, departa- mento de Antioquia. Metodología: se obtuvieron muestras de suero de donantes de sangre colectadas por la Cruz Roja Colombiana en una campaña de donación voluntaria en el municipio de Yarumal. En las muestras se determinó la presencia de anticuerpos anti-VHE tipo IgM e IgG mediante estuche comercial de ELISA. Resultados: se analizaron 42 muestras de suero, 19 de las cuales (45,2%) fueron positivas para anticuerpos anti-VHE IgG. Ninguna de las muestras fue positiva para anticuerpos anti-VHE tipo IgM. Conclusiones: este es el primer reporte de anticuerpos anti-VHE en donantes de sangre en Colombia. La frecuencia de anti-VHE (45,2%) es mayor a lo reportado previamente en otros estudios realizados en el país y a lo reportado en do- nantes de sangre en otros países de América Latina. Esta frecuencia podría estar relacionada con el contacto con cerdos infectados, así como con la exposición a agua contaminada con el virus. Sin embargo, estudios adicionales deben ser realizados en otras poblaciones similares en el país para confirmar este hallazgo.

An infusion of checkpoint blockade immunotherapy (CBI) has revolutionized cancer treatments for some patients, but the majority of patients experience disappointing responses. Because adaptive immune responses are mounted by the concentrated assembly of antigens, immune cells, and mediators in the secluded and protective environment of draining lymph nodes (dLNs), we hypothesize that lymphatic delivery of CBI (αCTLA-4 and αPD-1) to tumor dLNs (tdLNs) improves anti-tumor responses over intravenous (i.v.) administration, and that vaccination against tumor associated antigen (TAA) further enhances these responses. Mono- and combination CBI were administered i.v. or through image-guided intradermal (i.d.) injection to reach tdLNs in vaccinated and unvaccinated animals bearing either primary or orthotopically metastasizing B16F10 melanoma. Vaccination and boost against TAA, Melan-A, was accomplished with virus-like particles (VLP) directed to tdLNs followed by VLP boost after CBI administration. Lymphatic delivery of CBIs reduced primary tumor size and metastatic tumor burden, alleviated the pro-tumorigenic immune environment, and improved survival over systemic administration of CBIs. Animals receiving CBIs lymphatically exhibited significantly enhanced survival over those receiving therapies administered partially or completely through systemic routes. By combining vaccination and CBI for effective T-cell priming in the protected environment of dLNs, anti-tumor responses may be improved.

ERBB3 has gained attention as a potential therapeutic target to treat colorectal and other types of cancers. To confirm a previous study showing intestinal polyps are dependent upon ERBB3, we generated an intestinal epithelia-specific ERBB3 deletion in C57BL/6-ApcMin/+ mice. Contrary to the previous report showing a significant reduction in intestinal polyps with ablation of ERBB3 on a B6;129 mixed genetic background, we observed a significant increase in polyp number with ablation of ERBB3 on C57BL/6J compared to control littermates. We confirmed the genetic background dependency of ERBB3 by also analyzing polyp development on B6129 hybrid and B6;129 advanced intercross mixed genetic backgrounds, which showed that ERBB3 deficiency only reduced polyp number on the mixed background as previously reported. Increased polyp number with ablation of ERBB3 was also observed in C57BL/6J mice treated with azoxymethane showing the effect is model independent. Polyps forming in absence of ERBB3 were generally smaller than those forming in control mice, albeit the effect was greatest in genetic backgrounds with reduced polyp numbers. The mechanism for differential polyp number in the absence of ERBB3 was through altered proliferation. Backgrounds with increased polyp number with loss of ERBB3 showed an increase in cell proliferation even in non-tumor epithelia, while backgrounds showing reduced polyp number with loss of ERBB3 showed reduced cellular proliferation. Increase polyp number caused by loss of ERBB3 was mediated by increased epidermal growth factor receptor (EGFR) expression, which was confirmed by deletion of Egfr. Taken together, this study raises substantial implications on the use of ERBB3 inhibitors against colorectal cancer. The prediction is that some patients may have increased progression with ERBB3 inhibitor therapy, which is consistent with observations reported for ERBB3 inhibitor clinical trials.

Colorectal cancer (CRC) is the third most common cancer and second leading cause of cancer-related death in the United States. Substantial effort has gone into understanding molecular mechanisms governing CRC progression with the goal of developing potent targeted therapies. Epidermal growth factor receptor (EGFR) was one of the first molecular targeted therapies. However clinical trials using EGFR inhibitors are not as efficient, suggesting an alternative and independent EGFR-CRC progression mechanism. In this study, we also evaluated the importance of ERBB3, a related EGF receptor, in EGFR-independent colorectal cancer progression. Using intestine-specific genetic ablation of Egfr in the ApcMin/+ (genetic) and axozymethane (carcinogenic) CRC mouse models, we show that 10% of colonic tumors arise independent of EGFR activity. Molecular analysis confirmed the lack of Egfr in these tumors and the formal proof for the existence of an EGFR-independent pathway. Tumors developing in absence of EGFR are larger in size than those developing under normal EGFR activity suggesting that EGFR independent tumors may have a faster growth rate. We also have evidence that ERBB3 may mediate compensatory pathways. Using intestinal specific ablation of Erbb3 (Erbb3f/f) we previously showed that the number of intestinal tumors in the ApcMin/+ model is greatly reduced. Importantly, polyps forming in absence of ERBB3 are significantly smaller than controls, suggesting that normal levels of ERBB3 signaling is essential for tumor growth in the ApcMin/+ model. More recently, we have generated a combinatorial model that conditionally inactivates both Erbb3 and Egfr in the intestinal epithelia. These models will provide powerful tools to genetically dissect molecular pathways contributing to CRC, and aid in identifying molecular biomarkers that can differentiate EGFR-independent from EGFR-dependent CRC. These studies may advance understanding of ERBB biology during colonic tumorigenesis and help design better therapies in combination with EGFR-targeted agents. Citation Format: Carolina Mantilla-Rojas, Ming Yu, David Threadgill. Genetic dissection of mechanisms underlying epidermal growth factor receptor-independent colorectal cancer development. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr LB-039.