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Background Woodchucks (Marmota monax) are a well-accepted animal model for the investigation of spontaneous hepatocellular carcinoma (HCC). As HCC tumors obtain nutrient blood supply exclusively from the hepatic artery, hepatic artery infusion (HAI) has been applied to HCC. However, there is a scarcity of experimental animal models to standardize drug regimens and examine novel agents. The purpose of this study was to establish an HAI model in woodchucks. Materials and methods HAI ports were placed in the gastroduodenal artery (GDA) of 11 woodchucks. The ports were infused with either a vehicle (dextrose 5% in water) or an experimental drug, CBL0137, once a week for 3 wk. Technical success rates, anatomical variation, morbidity and mortality, and tumor responses between groups were analyzed. Results The GDA access was feasible and reproducible in all woodchucks (11/11). The average operation time was 95 ± 20 min with no increase in the levels of liver enzymes detected from either infusate. The most common morbidity of CBL0137 therapy was anorexia after surgery. One woodchuck died due to hemorrhage at the gallbladder removal site from hepatic coagulopathy. Significantly higher CBL0137 concentrations were measured in the liver compared with blood after each HAI. Tumor growth was suppressed after multiple CBL0137 HAI treatments which corresponded to greater T cell infiltration and increased tumor cell apoptosis. Conclusions HAI via GDA was a feasible and reproducible approach with low morbidity and mortality in woodchucks. The described techniques serve as a reliable platform for the identification and characterization of therapeutics for HCC.

The effects of TEMPO-mediated oxidized cellulose nanofibril (TOCN) on the viscoelastic behavior and phase of cellulose nanocrystal (CNC) in suspension and film were investigated using polarized optical microscopy, rotational rheometry, and dynamic mechanical analysis. The sodium cation from TOCN changed the electrostatic state of CNC by screening the CNC surface charge. The volume inflation of TOCN locally increased the CNC concentration in the suspension. In turn, the CNC-CNC interactions increased the viscosity and the yield stress. Based on the experimental observation, the changing mechanisms of electrostatic state and particular interaction in the TOCN/CNC suspensions were suggested. In the hybrid film, the time dependency of complex moduli was changed owing to the different networking between CNCs and TOCNs. The CNC-CNC contacts easily collapsed by strain, while the TOCN-TOCN entanglements were slowly altered. This study provides a fundamental understanding of CNC behavior for optimizing processes and composite properties.

BACKGROUND: The liver has unique anatomy in that most blood flow to normal hepatocytes is derived from the portal venous system, while liver tumors obtain their nutrient blood supply exclusively from the hepatic artery. The focused arterial delivery of anticancer agents to liver tumors has been performed for decades; however, preclinical models to standardize drug regimens and examine novel agents have been lacking. The purpose of this study was to establish preclinical hepatic artery infusion (HAI) models in a mouse, and to evaluate the safety and delivery capability of the models. MATERIAL AND METHODS: Female C57BL/6 and BALB/c mice aged 8–12 wk were used to develop models of HAI via the hepatic artery (HA), superior pancreaticoduodenal artery (SPDA), or lienogastric artery (LGA). Success rates, distribution of perfusion, and associated morbidity and mortality were analyzed between groups. RESULTS: All three models were feasible and reproducible in mice, and there was no statistical difference on body weight change between models. The HA model had a 13.3% mortality from acute liver failure, and the SPDA model demonstrated significant duodenal and pancreatic toxicity. SPDA and LGA routes had the highest success rates (96.7% and 91.4%, respectively) with low mortality, better drug delivery, and preserved physiologic liver function compared to the HA model. CONCLUSIONS: The optimal route of HAI was mouse breed-specific; SPDA access in BALB/c mice, and the LGA access in C57BL/6 mice. The described techniques serve as a reproducible platform for the identification and characterization of therapeutics for diverse metastatic liver tumors.

Background Water lavage (WL) during gastrointestinal cancer surgery has osmotically mediated lytic effects on tumor cells. We investigated the safety and efficacy of WL with CRS-HIPEC. Methods This is a retrospective review, 1/2003-7/2014, of a single institution experience with CRS-HIPEC comparing patients who had WL (WL+) to those who did not (WL−). Results Of 157 CRS-HIPECs, 16 (10.2%) were WL+. WL+ had more PCI scores >20 compared to WL− (56.3% vs 19.4%, respectively, p = 0.003); however, the completeness of cytoreduction (CC) was similar. There were no differences in hospital length of stay or post-operative complications. The average POD 1 sodium (Na) level was statistically lower in the WL+ group (133.6 ± 2.5 vs 135.5 ± 3.2 mEq/L, p = 0.023); however, the average Na at discharge for each group was 140 mEq/L. There were no differences in 3-year OS (3WL+:0.63 vs WL−:0.68, p = 0.97) or RFS (WL+:0.32 vs WL−:0.39, p = 0.47). A subset analysis for patients with PCI >20 showed no difference between groups. Conclusions WL offers a low cost, safe and theoretically efficacious method of tumor cell lysis for peritoneal malignancy.

Recent studies have reported conflicting results regarding the role of ARF6 in dendritic spine development, but no clear answer for the controversy has been suggested. We found that ADP-ribosylation factor 6 (ARF6) either positively or negatively regulates dendritic spine formation depending on neuronal maturation and activity. ARF6 activation increased the spine formation in developing neurons, whereas it decreased spine density in mature neurons. Genome-wide microarray analysis revealed that ARF6 activation in each stage leads to opposite patterns of expression of a subset of genes that are involved in neuronal morphology. ARF6-mediated Rac1 activation via the phospholipase D pathway is the coincident factor in both stages, but the antagonistic RhoA pathway becomes involved in the mature stage. Furthermore, blocking neuronal activity in developing neurons using tetrodotoxin or enhancing the activity in mature neurons using picrotoxin or chemical long term potentiation reversed the effect of ARF6 on each stage. Thus, activity-dependent dynamic changes in ARF6-mediated spine structures may play a role in structural plasticity of mature neurons.

Solid-pseudopapillary neoplasm is an uncommon pancreatic tumor with distinct clinicopathologic features. Solid-pseudopapillary neoplasms are characterized by mutations in exon 3 of CTNNB1. However, little is known about the gene and microRNA expression profiles of solid-pseudopapillary neoplasms. Thus, we sought to characterize solid-pseudopapillary neoplasm-specific gene expression and identify the signaling pathways activated in these tumors. Comparisons of gene expression in solid-pseudopapillary neoplasm to pancreatic ductal carcinomas, neuroendocrine tumors, and non-neoplastic pancreatic tissues identified solid-pseudopapillary neoplasm-specific mRNA and microRNA profiles. By analyzing 1686 (1119 upregulated and 567 downregulated) genes differentially expressed in solid-pseudopapillary neoplasm, we found that the Wnt/β-catenin, Hedgehog, and androgen receptor signaling pathways, as well as genes involved in epithelial mesenchymal transition, are activated in solid-pseudopapillary neoplasms. We validated these results experimentally by assessing the expression of β-catenin, WIF-1, GLI2, androgen receptor, and epithelial-mesenchymal transition-related markers with western blotting and immunohistochemistry. Our analysis also revealed 17 microRNAs, especially the miR-200 family and miR-192/215, closely associated with the upregulated genes associated with the three pathways activated in solid-pseudopapillary neoplasm and epithelial mesenchymal transition. Our results provide insight into the molecular mechanisms underlying solid-pseudopapillary neoplasm tumorigenesis and its characteristic less epithelial cell differentiation than the other common pancreatic tumors.

Background Isolated limb perfusion (ILP) for extremity melanoma has been used clinically for over half a century. Mouse modeling of ILP may offer significant experimental advantages compared with existing models. We propose a novel mouse model and report our initial experience. Methods We injected female C57BL/6 mice (22–25 g) with 1 × 106 B16 melanoma cells subcutaneously in the distal right thigh. After 7 d of tumor establishment, we cannulated the superficial femoral artery (inflow) and vein (outflow) of anesthetized mice and placed a proximal tourniquet. Non-oxygenated perfusate included low-dose or high-dose melphalan and saline (control). We analyzed endpoints of cannulation time, procedural complications, morbidity, toxicity, and tumor response. Results We performed 11 superficial femoral vessel cannulations. Median cannulation time was 19 min (range, 15–32 min). Intact perfusion models were obtained in 10 of 11 cases (91%); one case failed owing to superficial femoral vein dissection. Morbidity rate was 20% (one wound dehiscence and one hematoma). Both high- and low-dose melphalan perfusion groups (4 mice/group) trended to growth delay and regression compared with saline-perfused groups. Toxicity was greater in the high-dose melphalan-treated mice. Conclusions We have established the first reproducible mouse model of ILP for melanoma. Future experiments will take advantage of the large number of established mouse knockout models and reagents to dissect the precise mechanisms of tumor control after ILP, and examine to novel agents.

Homeobox (HOX) family genes, major transcription factors for embryonic development, have been also implicated in vascular development and angiogenesis, particularly with regulation of genes involved in cell-cell or cell-extracellular matrix (ECM) interactions. However, the cellular and molecular functions of HOXD1 in endothelial cells (ECs) are yet to be explored. We here report that HOXD1 is prominently expressed in human ECs and regulates angiogenic activities. Knockdown of HOXD1 in ECs resulted in significant inhibition of migration and adhesion as well as tube like structure formation. These effects were correlated with the reduced expression of integrin β1 (ITGB1), an important signaling component of angiogenesis. Consistently, ITGB1 promoter activity was decreased by HOXD1 knockdown in ECs. Furthermore, we identified the putative HOXD1-binding sites in the promoter region of ITGB1. Together, these findings suggest that HOXD1 plays a significant role in EC functions by regulating the expression of ITGB1.

Mel-18 is a mammalian homolog of Polycomb group (PcG) genes. Microarray analysis revealed that Mel-18 expression was induced during endothelial progenitor cell (EPC) differentiation and correlates with the expression of EC-specific protein markers. Overexpression of Mel-18 promoted EPC differentiation and angiogenic activity of ECs. Accordingly, silencing Mel-18 inhibited EC migration and tube formation in vitro. Gene expression profiling showed that Mel-18 regulates angiogenic genes including kinase insert domain receptor (KDR), claudin 5, and angiopoietin-like 2. Our findings demonstrate, for the first time, that Mel-18 plays a significant role in the angiogenic function of ECs by regulating endothelial gene expression.