Pharmacokinetics and Early Tumor Response to Conventional Transarterial Chemoembolization with Sorafenib and Doxorubicin in a VX2 Rabbit Tumor Model.

PURPOSE: To investigate the pharmacokinetics (PK) and early effects of conventional transarterial chemoembolization (TACE) using sorafenib and doxorubicin on tumor necrosis, hypoxia markers, and angiogenesis in a rabbit VX2 liver tumor model. MATERIALS AND METHODS: VX2 tumor-laden New Zealand White rabbits (N = 16) were divided into 2 groups: 1 group was treated with hepatic arterial administration of ethiodized oil and doxorubicin emulsion (DOX-TACE), and the other group was treated with ethiodized oil, sorafenib, and doxorubicin emulsion (SORA-DOX-TACE). Animals were killed within 3 days of the procedure. Levels of sorafenib and doxorubicin were measured in blood, tumor, and adjacent liver using mass spectrometry. Tumor necrosis was determined by histopathological examination. Intratumoral hypoxia-inducible factor (HIF) 1α, vascular endothelial growth factor (VEGF), and microvessel density (MVD) were determined by immunohistochemistry. RESULTS: The median intratumoral concentration of sorafenib in the SORA-DOX-TACE group was 17.7 µg/mL (interquartile range [IQR], 7.42-33.5 µg/mL), and its maximal plasma concentration (Cmax) was 0.164 µg/mL (IQR, 0.0798-0.528 µg/mL). The intratumoral concentration and Cmax of doxorubicin were similar between the groups: 4.08 µg/mL (IQR, 3.18-4.79 µg/mL) and 0.677 µg/mL (IQR, 0.315-1.23 µg/mL), respectively, in the DOX-TACE group and 1.68 µg/mL (IQR, 0.795-4.08 µg/mL) and 0.298 µg/mL (IQR, 0.241-0.64 µg/mL), respectively, in the SORA-DOX-TACE group. HIF-1α expression was increased in the SORA-DOX-TACE group than in the DOX-TACE group. Tumor volume, tumor necrosis, VEGF expression, and MVD were similar between the 2 groups. CONCLUSIONS: The addition of sorafenib to DOX-TACE delivered to VX2 liver tumors resulted in high intratumoral and low systemic concentrations of sorafenib without altering the PK of doxorubicin.

Conventional versus drug-eluting embolic transarterial chemoembolization with doxorubicin: comparative drug delivery, pharmacokinetics, and treatment response in a rabbit VX2 tumor model.

The purpose of this study was to compare intra-tumoral drug delivery, pharmacokinetics, and treatment response after doxorubicin (DOX) conventional (c-) versus drug-eluting embolic (DEE-) transarterial chemoembolization (TACE) in a rabbit VX2 liver tumor model. Twenty-four rabbits with solitary liver tumors underwent c-TACE (n = 12) (1:2 water-in-oil emulsion, 0.6 mL volume, 2 mg DOX) or DEE-TACE (n = 12) (130,000 70-150 µm 2 mg DOX-loaded microspheres). Systemic, intra-tumoral, and liver DOX levels were measured using mass spectrometry up to 7-day post-procedure. Intra-tumoral DOX distribution was quantified using fluorescence imaging. Percent tumor necrosis was quantified by a pathologist blinded to treatment group. Lobar TACE was successfully performed in all cases. Peak concentration (CMAX, µg/mL) for plasma, tumor tissue, and liver were 0.666, 4.232, and 0.270 for c-TACE versus 0.103, 8.988, and 0.610 for DEE-TACE. Area under the concentration versus time curve (AUC, µg/mL ∗ min) for plasma, tumor tissue, and liver were 18.3, 27,078.8, and 1339.1 for c-TACE versus 16.4, 26,204.8, and 1969.6 for DEE-TACE. A single dose of intra-tumoral DOX maintained cytotoxic levels through 7-day post-procedure for both TACE varieties, with a half-life of 1.8 (c-TACE) and 0.8 (DEE-TACE) days. Tumor-to-normal liver DOX ratio was high (c-TACE, 20.2; DEE-TACE, 13.3). c-TACE achieved significantly higher DOX coverage of tumor vs. DEE-TACE (10.8% vs. 2.3%; P = 0.003). Percent tumor necrosis was similar (39% vs. 37%; P = 0.806). In conclusion, in a rabbit VX2 liver tumor model, both c-TACE and DEE-TACE achieved tumoricidal intra-tumoral DOX levels and high tumor-to-normal liver drug ratios, though c-TACE resulted in significantly greater tumor coverage.

Sylvatic Canine Morbillivirus in Captive Panthera Highlights Viral Promiscuity and the Need for Better Prevention Strategies.

Canine Distemper Virus (CDV) is a multi-host morbillivirus that infects virtually all Carnivora and a few non-human primates. Here we describe a CDV outbreak in an exotic felid rescue center that led to the death of eight felids in the genus Panthera. Similar to domestic dogs and in contrast to previously described CDV cases in Panthera, severe pneumonia was the primary lesion and no viral antigens or CDV-like lesions were detected in the central nervous system. Four tigers succumbed to opportunistic infections. Viral hemagglutinin (H)-gene sequence was up to 99% similar to strains circulating contemporaneously in regional wildlife. CDV lesions in raccoons and skunk were primarily encephalitis. A few affected felids had at least one previous vaccination for CDV, while most felids at the center were vaccinated during the outbreak. Panthera sharing a fence or enclosure with infected conspecifics had significantly higher chances of getting sick or dying, suggesting tiger-tiger spread was more likely than recurrent spillover. Prior vaccination was incomplete and likely not protective. This outbreak highlights the need for further understanding of CDV epidemiology for species conservation and public health.

Development and comprehensive characterization of porcine hepatocellular carcinoma for translational liver cancer investigation.

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death worldwide. New animal models that faithfully recapitulate human HCC phenotypes are required to address unmet clinical needs and advance standard-of-care therapeutics. This study utilized the Oncopig Cancer Model to develop a translational porcine HCC model which can serve as a bridge between murine studies and human clinical practice. Reliable development of Oncopig HCC cell lines was demonstrated through hepatocyte isolation and Cre recombinase exposure across 15 Oncopigs. Oncopig and human HCC cell lines displayed similar cell cycle lengths, alpha-fetoprotein production, arginase-1 staining, chemosusceptibility, and drug metabolizing enzyme expression. The ability of Oncopig HCC cells to consistently produce tumors in vivo was confirmed via subcutaneous (SQ) injection into immunodeficient mice and Oncopigs. Reproducible development of intrahepatic tumors in an alcohol-induced fibrotic microenvironment was achieved via engraftment of SQ tumors into fibrotic Oncopig livers. Whole-genome sequencing demontrated intrahepatic tumor tissue resembled human HCC at the genomic level. Finally, Oncopig HCC cells are amenable to gene editing for development of personalized HCC tumors. This study provides a novel, clinically-relevant porcine HCC model which holds great promise for improving HCC outcomes through testing of novel therapeutic approaches to accelerate and enhance clinical trials.

Metastatic myxosarcoma in a Quarter Horse gelding.

A 22-y-old Quarter Horse gelding was presented to the University of Illinois Veterinary Teaching Hospital for evaluation of increased heart rate and mild colic signs. Rectal examination revealed a large left perirenal mass. Abdominal ultrasonography further confirmed this finding. Thoracic ultrasonography indicated multifocal irregularities on the pleural surface suggestive of consolidation and possibly masses in the lungs. The animal was euthanized. Autopsy findings included a large, firm, expansile, gelatinous retroperitoneal mass that surrounded both kidneys, as well as nodules with similar morphology in the lungs, liver, intestinal mesentery, cecum, and caudal mesenteric artery. Histologically, the masses were composed of neoplastic stellate-to-spindloid cells in abundant mucinous stroma. Neoplastic cells exhibited strong immunoreactivity for vimentin and were negative for pancytokeratin (A1/A3), CD3, CD20, melan A, and synaptophysin. Mucinous stroma was strongly positive with alcian blue and weakly positive with periodic acid-Schiff histochemical staining. These findings are consistent with metastatic myxosarcoma. Myxosarcoma is a rare neoplasm in horses, and metastasis to tissues other than sentinel lymph nodes has not been described previously to our knowledge.

Coactivation of Estrogen Receptor and IKKß Induces a Dormant Metastatic Phenotype in ER-Positive Breast Cancer.

A growing body of evidence suggests that the inflammatory NFκB pathway is associated with the progression of ER+ tumors to more aggressive stages. However, it is unknown whether NFκB is a driver or a consequence of aggressive ER+ disease. To investigate this question, we developed breast cancer cell lines expressing an inducible, constitutively active form of IκB kinase ß (CA-IKKß), a key kinase in the canonical NFκB pathway. We found that CA-IKKß blocked E2-dependent cell proliferation in vitro and tumor growth in vivo in a reversible manner, suggesting that IKKß may contribute to tumor dormancy and recurrence of ER+ disease. Moreover, coactivation of ER and IKKß promoted cell migration and invasion in vitro and drove experimental metastasis in vivo Gene expression profiling revealed a strong association between ER and CA-IKKß-driven gene expression and clinically relevant invasion and metastasis gene signatures. Mechanistically, the invasive phenotype appeared to be driven by an expansion of a basal/stem-like cell population rather than EMT. Taken together, our findings suggest that coactivation of ER and the canonical NFκB pathway promotes a dormant, metastatic phenotype in ER+ breast cancer and implicates IKKß as a driver of certain features of aggressive ER+ breast cancer.Significance: The canonical NFκB pathway promotes expansion of stem/basal-like cells and a dormant, metastatic phenotype in ER+ breast cancer cells. Cancer Res; 78(4); 974-84. ©2017 AACR.

Veterinary Curriculum Transformation at the University of Illinois, 2006-2016.

The organization and delivery of a curriculum is the responsibility of the faculty in educational institutions. Curricular revision is often a hotly debated topic in any college faculty. At the University of Illinois, a 2006 mandate for curriculum modernization from the American Veterinary Medical Association Council on Education provided impetus for a long-discussed curricular revision. After two iterations and a lengthy development process, a new curriculum was gradually implemented at Illinois with the August 2009 matriculation of the Class of 2013. The goals of the revision included earlier clinical exposure for veterinary students through introductions to clinical rotations in years 1 to 3 and an integrated body systems approach in lecture/laboratory courses. A new Clinical Skills Learning Center facilitates development of clinical skills earlier in the curriculum and promotes the development of those skills throughout all 4 years of the curriculum. New outcomes assessments include comprehensive written examinations and Objective Structured Clinical Examinations (OSCEs) in years 2 and 3. Curriculum management, including grading of clinical rotations in all 4 years, is achieved through a commercially available software package. For the past 5 years, when candidates were asked why they chose to apply to Illinois, the new curriculum (27.4%) was the most common answer given during interviews. The Illinois revision has resulted in measurably increased veterinary student self-confidence (p<.001) at graduation.

Hyperelastic "bone": A highly versatile, growth factor-free, osteoregenerative, scalable, and surgically friendly biomaterial.

Despite substantial attention given to the development of osteoregenerative biomaterials, severe deficiencies remain in current products. These limitations include an inability to adequately, rapidly, and reproducibly regenerate new bone; high costs and limited manufacturing capacity; and lack of surgical ease of handling. To address these shortcomings, we generated a new, synthetic osteoregenerative biomaterial, hyperelastic "bone" (HB). HB, which is composed of 90 weight % (wt %) hydroxyapatite and 10 wt % polycaprolactone or poly(lactic-co-glycolic acid), could be rapidly three-dimensionally (3D) printed (up to 275 cm(3)/hour) from room temperature extruded liquid inks. The resulting 3D-printed HB exhibited elastic mechanical properties (~32 to 67% strain to failure, ~4 to 11 MPa elastic modulus), was highly absorbent (50% material porosity), supported cell viability and proliferation, and induced osteogenic differentiation of bone marrow-derived human mesenchymal stem cells cultured in vitro over 4 weeks without any osteo-inducing factors in the medium. We evaluated HB in vivo in a mouse subcutaneous implant model for material biocompatibility (7 and 35 days), in a rat posterolateral spinal fusion model for new bone formation (8 weeks), and in a large, non-human primate calvarial defect case study (4 weeks). HB did not elicit a negative immune response, became vascularized, quickly integrated with surrounding tissues, and rapidly ossified and supported new bone growth without the need for added biological factors.

Canine pre-iridal fibrovascular membranes: morphologic and immunohistochemical investigations.

OBJECTIVE: Pathologic intraocular neovascularization is a key component of many canine ophthalmic diseases such as uveitis, retinal detachment, intraocular neoplasms, and corneal perforation. The purpose of this study was to evaluate the structure of pre-iridal fibrovascular membranes (PIFMs) associated with several different disease processes and to identify specific factors associated with their development in the canine eye. PROCEDURE: This study examined 36 enucleated canine eyes with the diagnosis of PIFM and one of the following: lens-induced uveitis, retinal detachment, iridociliary adenoma, corneal perforation, severe hyphema, or vitreal gliovascular membranes (canine ocular gliovascular syndrome, COGS). Three histologic stains and six immunohistochemical stains were performed in all 36 PIFM eyes and four histologically normal eyes, including: hematoxylin and eosin, alcian blue periodic acid schiff (PAS), Masson's trichrome, platelet endothelial cell adhesion molecule-1 (CD31), smooth muscle actin, vimentin, laminin, vascular endothelial growth factor (VEGF), and cyclooxygenase-2 (COX-2). RESULTS: Pre-iridal fibrovascular membrane extracellular matrix staining was consistent with collagen and mucins in all cases and positive for laminin in most cases. All PIFMs contained CD31-positive vessels and predominantly lymphoplasmacytic inflammation. Both PIFM vessels and spindle cells were positive for laminin, vimentin, smooth muscle actin, VEGF, and COX-2. Secondary intraocular pathology and immunohistochemical staining of other intraocular structures are also reported. CONCLUSIONS: Pre-iridal fibrovascular membrane morphology and immunohistochemical characteristics were similar across six canine disease processes, suggesting analogous pathophysiologic mechanisms. COX-2 and VEGF were identified using immunohistochemistry and may play a role in PIFM development.

Preliminary analysis of azoxymethane induced colon tumors in inbred mice commonly used as transgenic/knockout progenitors.

Azoxymethane (AOM) is a colon carcinogen that is used to study the pathogenesis of sporadic colorectal cancer. We have evaluated differential susceptibility to AOM in inbred mice used as progenitors of recombinant/transgenic lines. In experiment 1, male FVB/N, 129/SvJ, C57Bl/6J mice were treated i.p. with 10 mg/kg AOM once per week for 4 weeks and sacrificed after 20 weeks. Only AOM-treated FVB/N mice developed tumors (3.6 tumors/mouse) in distal colon. In experiment 2, A/J, AKR/J, Balb/CJ mice were treated with AOM for 6 weeks and sacrificed after 24 weeks. AOM-treated A/J and Balb/CJ mice developed 9.2 and 1 tumor/mouse, respectively. Despite these differences, tumors had similar morphology regardless of strain. Immunohistochemistry with beta-catenin resulted in marked nuclear and cytoplasmic staining of tumor cells in FVB/N. However, fainter and heterogeneous beta-catenin staining was observed in A/J tumors, suggesting distinct pathways of tumorigenesis in different strains. Irrespective of cytological features of malignancy, tumor cells rarely breached the muscularis mucosa and showed no evidence of distant metastasis. Lack of invasiveness and metastasis in even the most sensitive strains provides a model system for studying the potential role of 'metastasis genes' in imparting a malignant phenotype.

Protection against acetaminophen hepatotoxicity by clofibrate pretreatment: role of catalase induction.

Mice pretreated with the peroxisome proliferator clofibrate (CFB) are highly resistant to acetaminophen (APAP)-induced hepatotoxicity. The objective of the present study was to investigate whether the increase in hepatic catalase activity following CFB pretreatment plays a role in this hepatoprotection. An irreversible inhibitor, 3-amino-1,2,4-triazole (3-AT), was used to modulate catalase activity. Hepatic catalase activity in mice pretreated with CFB (500 mg/kg, i.p., for 10 days) was significantly inhibited by 3-AT (100 or 500 mg/kg, i.p.). In addition, the lower dose of 3-AT (100 mg/kg) had minimal effect on biliary and urinary excretion of APAP metabolites generated from a nontoxic dose, suggesting that APAP metabolism was not modulated by this dose of 3-AT. The mortality rate of corn-oil-pretreated mice challenged with APAP (800 mg/kg, p.o.) was significantly increased by 3-AT (100 mg/kg, i.p.) given 1 h before APAP. As expected, CFB pretreatment conferred full protection against APAP-induced hepatotoxicity. The same 3-AT treatment, however, did not abolish hepatoprotection in CFB-pretreated mice, despite the marked inhibition of hepatic catalase activity. In conclusion, these results indicate that elevated catalase activity in mice exposed to CFB does not appear to mediate the hepatoprotection, suggesting that other cellular defense mechanisms are involved.

Ocular lesions associated with attachment of the copepod Ommatokoita elongata (Lernaeopodidae: Siphonostomatoida) to corneas of Pacific sleeper sharks Somniosus pacificus captured off Alaska in Prince William Sound.

Twenty eyes from 10 Pacific sleeper sharks Somniosus pacificus, infected with the copepod Ommatokoita elongata, were collected in Prince William Sound, Alaska, and the eyes of an additional 18 S. pacificus captured in the same area were inspected for copepods. Prevalence of infection by adult female O. elongata was 97% (n = 28); mean intensity of infection was 1.89 (+/-1SD = 0.32) adult female copepods per infected shark and 1.0 (+/- 1SD = 0.0) adult female copepods per infected eye. Five of the 20 collected eyes were infected by O. elongata chalimi, and 9 of 20 eyes had 1 to several remnants of bullae embedded in the cornea. Bullae were each associated with a corneal opacity, and anchoring plugs of chalimi were associated with pinpoint lesions in the cornea or conjunctiva. All eyes exhibited marked edema and erosion of the bulbar conjunctiva, and this torus-shaped lesion corresponded to each O. elongata adult female's presumed feeding and abrasion radius. Histological examinations revealed lesions in the anterior segment of eyes to be generally similar, but graded, in severity, and in all eyes they involved the conjunctiva, cornea, filtration angle, and iris. Epithelial lesions were characterized by corneal ulceration, dysplasia, hyperplasia, and heterophilic keratitis, and by ulcerative conjunctivitis accompanied by epithelial hyperplasia with rete peg formation. Disorganization of fibers, necrosis, mineralization, minimal heterophilic influx, and perilimbic neovascularization were associated with bullae in the corneal stroma. Within the limbus there was diffuse histiocytic and lymphocytic inflammation and marked lymphofollicular hyperplasia. Heterophilic and mononuclear anterior uveitis affecting the filtration angle and anterior surface of the iris was also observed in most eyes. One eye had a partial transcorneal prolapse of a ruptured lens, with degenerative changes in the ruptured lens and severe keratitis associated with the anchoring devices of an adult copepod and several chalimi. Fourteen eyes exhibited 1 to several, randomly distributed, small, round to irregular, corneal opacities or pits that were not associated with copepods, and it is likely that these opacities represented lesions associated with adult female or larval anchoring devices from past infections. The avascular cornea represents a niche that is somewhat shielded from host immune reactions, and this, and the fact that the general body surface of sleeper sharks is covered by tall and sharp placoid scales, may partially explain the corneal attachment of O. elongata adult females. It was concluded that O. elongata infections can lead to severe vision impairment in Pacific sleeper sharks but that these infections do not significantly debilitate hosts because they probably do not need to rely on acute vision for their survival.