FES null mice demonstrate a reduction in neutrophil dependent pancreatic cancer metastatic burden.

Patients with pancreatic ductal adenocarcinoma (PDAC) have a dismal 5-year survival rate of less than 10%, predominantly due to delayed diagnosis and a lack of effective treatment options. In the PDAC tumor microenvironment (TME), neutrophils are among the immune cell types that are most prevalent and are linked to a poor clinical prognosis. However, treatments that target tumor-associated neutrophils are limited despite recent developments in our understanding of neutrophil function in cancer. The feline sarcoma oncogene (FES) is a nonreceptor tyrosine kinase previously associated with leukemia and hematopoietic homeostasis. Here we describe a newly derived FES null mouse with no distinct phenotype and no defects in hematopoietic homeostasis including neutrophil viability. The immune cell composition and neutrophil population were analyzed with flow cytometry, colony-forming unit (CFU) assay, and a neutrophil viability assay, while the response to PDAC was examined with an in vivo cancer model. In an experimental metastasis model, the FES null model displayed a reduced PDAC hepatic metastatic burden and a reduction in neutrophils granulocytes. Accordingly, our results indicate FES as a potential target for PDAC TME modulation.

In vivo effect of rFVIII and rFVIIa in hemophilia A rats evaluated by the Tail Vein Transection Bleeding Model.

BACKGROUND: Preclinical bleeding models increase current hemophilia A (HA) knowledge and aid the development of new pharmacological treatments. There are several well-established mouse bleeding models, but limited options are available for rat models despite their high resemblance to human disease process. OBJECTIVE: To provide a comprehensive description of the tail vein transection (TVT) bleeding model in HA rats and examine the correlation between in vivo pharmacological efficacy and global hemostatic assays. METHODS: The TVT bleeding model was implemented in HA rats and used to perform dose-response studies with recombinant coagulation factors VIIa (rFVIIa) and VIII (rFVIII). After the TVT bleeding model, whole blood and plasma were collected from rats and evaluated with thrombin generation test (TGT) and rotational thromboelastometry (ROTEM). RESULTS: Using the TVT bleeding model, the potency of rFVIII and rFVIIa treatments in HA rats were assessed, and the pharmacological windows established for rFVIII (≤15 U/kg) and rFVIIa (≤2.7 mg/kg). ED50 was estimated to be 1.75 U/kg for rFVIII and 0.37 mg/kg for rFVIIa, whereas complete normalization was observed with 15 U/kg and 2.7 mg/kg respectively. Furthermore, responses to rFVIII and rFVIIa in the TGT and ROTEM assays strongly correlated to in vivo pharmacological efficacy. CONCLUSION: The TVT bleeding model in HA rats is a useful tool to assess the pharmacodynamic effects of hemostatic compounds in vivo, and strongly correlates to results obtained with TGT and ROTEM in HA rats, adding further value to the HA rat model in preclinical research.

Exercise suppresses tumor growth independent of high fat food intake and associated immune dysfunction.

Epidemiological data suggest that exercise training protects from cancer independent of BMI. Here, we aimed to elucidate mechanisms involved in voluntary wheel running-dependent control of tumor growth across chow and high-fat diets. Access to running wheels decreased tumor growth in B16F10 tumor-bearing on chow (- 50%) or high-fat diets (- 75%, p < 0.001), however, tumor growth was augmented in high-fat fed mice (+ 53%, p < 0.001). Tumor growth correlated with serum glucose (p < 0.01), leptin (p < 0.01), and ghrelin levels (p < 0.01), but not with serum insulin levels. Voluntary wheel running increased immune recognition of tumors as determined by microarray analysis and gene expression analysis of markers of macrophages, NK and T cells, but the induction of markers of macrophages and NK cells was attenuated with high-fat feeding. Moreover, we found that the regulator of innate immunity, ZBP1, was induced by wheel running, attenuated by high-fat feeding and associated with innate immune recognition in the B16F10 tumors. We observed no effects of ZBP1 on cell cycle arrest, or exercise-regulated necrosis in the tumors of running mice. Taken together, our data support epidemiological findings showing that exercise suppresses tumor growth independent of BMI, however, our data suggest that high-fat feeding attenuates exercise-mediated immune recognition of tumors.

Voluntary wheel running can lead to modulation of immune checkpoint molecule expression.

BACKGROUND: Exercise and physical activity (PA) are associated with reduced tumor growth and enhanced intra-tumoral immune cell infiltration in mice. We aimed to investigate the role of PA achieved by voluntary wheel running in promoting the immunogenic profile across several murine tumor models, and to explore the potential of checkpoint blockade and PA in the form of voluntary wheel running as combination therapy. MATERIAL AND METHODS: The experiments were performed with C57BL/6 mice bearing subcutaneous tumors while having access to running wheels in their cages, where key immunoregulatory molecules expressed in the tumor tissue were measured by qPCR. Furthermore, we tested the hypothesis that wheel running combined with PD-L1 -or PD-1 inhibitor treatment could lead to an additive effect on tumor growth in mice bearing B16 melanoma tumors. RESULTS: Wheel running increased immune checkpoint expression (PD-1, PD-L1, PD-L2, CD28, B7.1 and B7.2) in B16 tumor-bearing mice, while induction of only PD-L2 was found in E0771 breast cancer and Lewis Lung Cancer. In studies combining voluntary wheel running with PD-1 -and PD-L1 inhibitors we found significant effects of wheel running on attenuating B16 melanoma tumor growth, in line with previous studies. We did, however, not find an additive effect of combining either of the two immunotherapeutic treatments with access to running wheels. CONCLUSION: B16 tumors displayed upregulated expression of immune regulatory molecules and decreased tumor growth in response to PA. However, combining PA with PD-1 or PD-L1 blockade did not lead to a further augmented inhibition of tumor growth.

Absence of functional compensation between coagulation factor VIII and plasminogen in double-knockout mice.

Plasminogen deficiency is associated with severely compromised fibrinolysis and extravascular deposition of fibrin. In contrast, coagulation factor VIII (FVIII) deficiency leads to prolonged and excessive bleeding. Based on opposing biological functions of plasminogen and FVIII deficiencies, we hypothesized that genetic elimination of FVIII would alleviate the systemic formation of fibrin deposits associated with plasminogen deficiency and, in turn, elimination of plasminogen would limit bleeding symptoms associated with FVIII deficiency. Mice with single and combined deficiencies of FVIII (F8-/-) and plasminogen (Plg-/-) were evaluated for phenotypic characteristics of plasminogen deficiency, including wasting disease, shortened lifespan, rectal prolapse, and multiorgan fibrin deposition. Conversely, to specifically examine the role of plasmin-mediated fibrinolysis on bleeding caused by FVIII deficiency, F8-/- and F8-/-/Plg-/- mice were subjected to a bleeding challenge. Mice with a combined deficiency in FVIII and plasminogen displayed no phenotypic differences relative to mice with single FVIII or plasminogen deficiency. Plg-/- and F8-/-/Plg-/- mice exhibited the same penetrance and severity of wasting disease, rectal prolapse, extravascular fibrin deposits, and reduced viability. Furthermore, following a tail vein-bleeding challenge, no significant differences in bleeding times or total blood loss could be detected between F8-/- and F8-/-/Plg-/- mice. Moreover, F8-/- and F8-/-/Plg-/- mice responded similarly to recombinant FVIII (rFVIII) therapy. In summary, the pathological phenotype of Plg-/- mice developed independently of FVIII-dependent coagulation, and elimination of plasmin-driven fibrinolysis did not play a significant role in a nonmucosal bleeding model in hemophilia A mice.