Extent Of Angiogenesis Research Articles

Comparison of Decellularized Human Dermal Scaffolds versus Bovine Collagen/Elastin Matrices for Engineering of Soft-Tissue Flaps.

Free flap-based soft-tissue reconstruction comes at the price of donor-site morbidity. The arteriovenous loop (AVL) technique can overcome this issue by allowing for the de novo generation of axially vascularized soft-tissue flaps from vein grafts embedded into different matrices. Application of the AVL technique has been limited by insufficient long-term volume retention and poor tissue stability. The authors investigated the suitability of a novel human dermal scaffold to improve volume retention and tissue stability. AVLs were created in 28 immunocompetent rats and embedded in either decellularized human dermal scaffolds (experimental group, n = 14) (Epiflex) or bovine collagen/elastin matrices (control group, n = 14) (MatriDerm) in subcutaneous polytetrafluoroethylene chambers. The weight and volume of engineered tissues, the extent of angiogenesis, and the proportion of proliferating cells were compared between groups on postoperative days (PODs) 21 and 28 by means of immunohistochemistry and micro-computed tomography. On POD 28, both groups displayed homogeneous microvascular networks on histopathology and micro-computed tomography. Mean microvessel counts and surface areas and the percentage of proliferating cells did not differ between the groups. However, the experimental human scaffold group displayed significantly smaller volume loss and significantly less tissue degradation compared with bovine matrix controls (volume retention, 102% ± 5% versus 27% ± 7% on POD 21, and 79% ± 12% versus 12% ± 7% on POD 28, respectively; P < 0.0001). Compared with bovine matrices, decellularized human scaffolds allow for superior volume retention and tissue stability of de novo engineered soft-tissue AVL flaps in rats. AVLs allow for the de novo generation of vascularized soft-tissue flaps. However, insufficient long-term volume retention is still an issue. The authors' study shows that decellularized human matrices guarantee superior volume stability of de novo grown soft-tissue flaps in rats.

Effects of the Hydnophytum formicarum plant extract on collagen density, angiogenesis, wound length, and re-epithelialization in wound healing: Experimental study on rats.

The formation of scar tissue in the wound healing process is associated with fibroblasts that are produced during the proliferation phase (3-14 days after surgery/injury). One of the strategies to suppress the formation of excessive scar tissue is to use wound care material. The use of herbal extracts is currently being investigated by researchers, as it allows avoiding the side effects of synthetic drugs. The Hydnophytum formicarum extract has antioxidant and anti-inflammatory potential. The aim of the study was to analyze the effects of the Hydnophytum formicarum plant extract on collagen density, angiogenesis, wound length, and re-epithelialization in wound healing. Twenty-four Sprague-Dawley rats were divided into 2 groups: the control group; and the treatment group. Skin wounds were made on the dorsum of the rats, using the biopsy punch technique. Four rats from each group were sacrificed on days 4, 7 and 14 after injury. Collagen density, angiogenesis, wound length, and re-epithelialization were analyzed using hematoxylin and eosin (H&E) staining and Masson's trichrome staining. There were significant differences in the results of the angiogenesis analysis, wound length and re-epithelialization between the treatment and control groups. When considering angiogenesis, there were fewer vessels in the treatment group, but they were more mature as compared to the control group. There was also a meaningful interaction between the application of the Hydnophytum formicarum extract and the necropsy day with regard to collagen density and the re-epithelialization rate. No secondary infection was found in either group. The topical use of the Hydnophytum formicarum extract affected the formation of scar tissue, as indicated by the positive area of collagen, the extent of angiogenesis, wound length, and the re-epithelialization rate in the early, middle and final granulation phases. The inhibition of angiogenesis through the application of Hydnophytum formicarum was probably related to the formation of scar tissue in the wound.

Effect of snail mucus on angiogenesis during wound healing

Background: Angiogenesis is the process through which new blood vessels are formed from existing ones. This process plays an important role in supplying the oxygen and nutrients needed for cellular metabolism and eliminating cell debris during wound healing. Snail mucus can bind to several factors that stimulate angiogenesis, including vascular endothelial growth factor, platelet-derived growth factor, and fibroblast growth factor. The aim of this study is to observe changes in angiogenesis during the healing of wounds topically applied with snail mucus. Methods: Punch biopsy was performed on the back of male Wistar rats to obtain four wounds, and different concentrations of snail mucus were applied to each of these wounds. The animals were sacrificed on days 2, 4, and 7 to observe the extent of angiogenesis during wound healing by microscopy. Results: Two-way ANOVA showed differences in number of blood vessels formed (p = 0.00) and day of observation (p = 0.00) between groups. Post hoc Tukey’s HSD test showed that 24% snail mucus treatment does not significantly affect wound healing (p = 0.488); by contrast, treatment with 48% and 96% snail mucus demonstrated significant effects on angiogenesis (p = 0.01). Spearman’s test showed interactive effects between snail mucus concentration and day of observation on the extent of angiogenesis (p = 0.001, R = 0.946). Conclusion: Topical application of snail mucus gel can increase angiogenesis during wound healing in Wistar rat skin.

Angiogenic property of silk fibroin scaffolds with adipose-derived stem cells on chick chorioallantoic membrane.

Angiogenesis is a crucial step in tissue regeneration and repair. Biomaterials that allow or promote angiogenesis are thus beneficial. In this study, angiogenic properties of salt-leached silk fibroin (SF) scaffolds seeded with human adipose stem cells (hADSCs) were studied using chick chorioallantoic membrane (CAM) as a model. The hADSC-seeded SF scaffolds (SF-hADSC) with the porosity of 77.34 ± 6.96% and the pore diameter of 513.95 ± 4.99 µm were implanted on the CAM of chick embryos that were on an embryonic day 8 (E8) of development. The SF-hADSC scaffolds induced a spoke-wheel pattern of capillary network indicative of angiogenesis, which was evident since E11. Moreover, the ingrowth of blood vessels into the scaffolds was seen in histological sections. The unseeded scaffolds induced the same extent of angiogenesis later on E14. By contrast, the control group could not induce the same extent of angiogenesis. In vitro cytotoxicity tests and in vivo angioirritative study reaffirmed the biocompatibility of the scaffolds. This work highlighted that the biocompatible SF-hADSC scaffolds accelerate angiogenesis, and hence they can be a promising biomaterial for the regeneration of tissues that require angiogenesis.

Inflammation-driven vascular dysregulation in chronic rhinosinusitis.

Altered neovascularity is typically observed in chronic inflammatory diseases with overlapping pathophysiology to that observed in chronic rhinosinusitis (CRS). However, characterization of these inflammatory-induced vascular-mediated changes in CRS is limited. Understanding the underlying vascular changes in CRS will allow for strategic design and development of new drug-delivery technologies that exploit vascular permeability for increased extravasation into the target sinonasal tissues. Patients with CRS with nasal polyps (CRSwNP) and without nasal polyps (CRSsNP) and non-CRS controls were enrolled in this prospective, observational study. The extent of angiogenesis in tissue was characterized using immunohistochemical and multiplex gene expression analyses. Vascular permeability, interendothelial junction structures, and endothelial barrier morphology were evaluated using transmission electron microscopy. Sinonasal vascularity was increased significantly in CRSsNP and CRSwNP (p < 0.05) when compared with controls, as assessed by enumerating the platelet endothelial cell adhesion molecule (PECAM-1)-positive blood vessels. Pro-angiogenic gene expression, including PECAM1 and platelet-activating factor receptor, was elevated significantly in patients with CRSwNP when compared with controls (p < 0.05). The fenestration sizes between endothelial cells (17-280 nm) were larger in CRSwNP compared with CRSsNP (10-33 nm) patients and controls (4-12 nm). Global thinning of the endothelial cell lining was observed in CRS patients but not in controls. Significant increases in vascularity, the pro-angiogenic gene, and protein expression and blood vessel morphogenesis were observed in CRS patients compared with controls. In addition, fenestration sizes between interendothelial junction structures were larger in CRS patients than in controls, suggesting inflammation-driven vascular dysregulation in CRS pathology.

Allogeneic adipose-derived mesenchymal stem cell sheet that produces neurological improvement with angiogenesis and neurogenesis in a rat stroke model.

Stem cell therapy is a promising strategy for the treatment of severe cerebral ischemia. However, targeting sufficient grafted cells to the affected area remains challenging. Choosing an adequate transplantation method for the CNS appears crucial for this therapy to become a clinical reality. The authors used a scaffold-free cell sheet as a translational intervention. This method involves the use of cell sheet layers and allows the transplantation of a large number of cells, locally and noninvasively. The authors evaluated the effectiveness of allogeneic adipose tissue-derived mesenchymal stem cell sheets in a rat model of stroke. The animals, subjected to middle cerebral artery occlusion, were randomly divided in two groups: one in which a cell sheet was transplanted and the other in which a vehicle was used (n = 10/group). Over a period of 14 days after transplantation, the animals' behavior was evaluated, after which brain tissue samples were removed and fixed, and the extent of angiogenesis and infarct areas was evaluated histologically. Compared to the vehicle group, in the cell sheet group functional angiogenesis and neurogenesis were significantly increased, which resulted in behavioral improvement. Transplanted cells were identified within newly formed perivascular walls as pericytes, a proportion of which were functional. Newly formed blood vessels were found within the cell sheet that had anastomosed to the cerebral blood vessels in the host. The transplantation approach described here is expected to provide not only a paracrine effect but also a direct cell effect resulting in cell replacement that protects the damaged neurovascular unit. The behavioral improvement seen with this transplantation approach provides the basis for further research on cell sheet-based regenerative treatment as a translational treatment for patients with stroke.

Bone marrow stromal cells transplantation promotes the resolution and recanalization of deep vein thrombosis in rabbits through regulating macrophage infiltration and angiogenesis.

This study aims to validate whether bone marrow stromal cells (BMSCs) transplantation could promote the resolution and recanalization of deep vein thrombosis (DVT) and to explore the underlying mechanism. The right hind femoral vein was embolized to establish the DVT rabbit model. BMSCs from New Zealand white rabbits were isolated and identified, and then injected into DVT rabbits. After that, the extent of angiogenesis was determined by the amount of capillaries that were positive for antibody against vWF. Macrophage infiltration was measured by immunohistochemistry with F4/80 antibody. M1 or M2 macrophages were identified as F4/80 + CD11c + or F4/80 + CD206 + cells by using flow cytometry analysis, respectively. BMSCs were successfully isolated and identified. BMSCs transplantation promotes macrophage infiltration and angiogenesis in DVT rabbits. BMSCs transplantation causes M1/M2 polarization, altered cytokine production and increased monocyte chemotactic protein 1 (MCP-1) protein expression in DVT rabbits. However, injection of MCP-1 protein not only reversed the effects of BMSCs transplantation on macrophage infiltration and angiogenesis, but also reversed the effects of BMSCs transplantation on M1/M2 polarization and cytokine production in DVT rabbits. BMSCs transplantation promotes the resolution and recanalization of DVT in rabbits through regulating macrophage infiltration and angiogenesis, the underlying mechanism is associated with MCP-1 expression.

Reactive Ductules Are Associated With Angiogenesis and Tumor Cell Proliferation in Pediatric Liver Cancer.

While reactive ductules (RDs) have been observed in viral hepatitis, biliary atresia, nonalcoholic fatty liver disease, and adult hepatocellular carcinoma (HCC), RDs in pediatric liver cancer remain uncharacterized. This study investigated the relationship of RDs with angiogenic paracrine factors, the extent of angiogenesis, and tumor cell proliferation in pediatric hepatoblastoma (HBL)/HCC livers. We quantified the extent of RDs and their expression of paracrine factors that include vascular endothelial growth factor (VEGF), vascular endothelial growth factor D (VEGFD), platelet‐derived growth factor C, and angiopoietin 1 (ANGPT1). In addition, we performed immunohistochemical detection of the endothelial marker clusters of differentiation (CD)34 and the proliferation marker Ki67 followed by correlation analyses. In HBL, we found the percentage of RDs with Ki67 expression (% Ki67+ RDs) significantly correlated with intratumoral Ki67+ areas (r = 0.5138, P = 0.0349) and % ANGPT1+ RDs positively correlated with % Ki67+ RDs (r = 0.5851, P = 0.0136). In HCC, the high ANGPT1+ RDs group (i.e., cases with % ANGPT1+ RDs ≥50) exhibited high intratumoral Ki67+ areas compared to the low ANGPT1+ RDs group. In the combined HBL and HCC liver tumor group, there was a positive association between % platelet‐derived growth factor C+ RDs and intratumoral Ki67+ areas (r = 0.4712, P = 0.0099) and the high VEGFD+ RDs group (≥50%) exhibited a high number of peritumoral CD34+ vessels compared to the low VEGFD+ RDs group. Conclusion: Paracrine factor‐expressing RDs are associated with angiogenesis and proliferation of pediatric liver tumors.

Histopathological growth patterns as a candidate biomarker for immunomodulatory therapy.

The encroachment of a growing tumor upon the cells and structures of surrounding normal tissue results in a series of histopathological growth patterns (HGPs). These morphological changes can be assessed in hematoxylin-and-eosin (H&E) stained tissue sections from primary and metastatic tumors and have been characterized in a range of tissue types including liver, lung, lymph node and skin. HGPs in different tissues share certain general characteristics like the extent of angiogenesis, but also appropriate tissue-specific mechanisms which ultimately determine differences in the biology of HGP subtypes. For instance, in the well-characterized HGPs of liver metastases, the two main subtypes, replacement and desmoplastic, recapitulate two responses of the normal liver to injury: regeneration and fibrosis. HGP subtypes have distinct cytokine profiles and differing levels of lymphocytic infiltration which suggests that they are indicative of immune status in the tumor microenvironment. HGPs predict response to bevacizumab and are associated with overall survival (OS) after surgery for liver metastases in colorectal cancer (CRC). In addition, HGPs can change over time in response to therapy. With standard scoring methods being developed, HGPs represent an easily accessible, dynamic biomarker to consider when determining strategies for treatment using anti-VEGF and immunomodulatory drugs.

Freeze-dried and irradiated allograft bone combined with fresh autologous coagula promotes angiogenesis in an ectopic bone allograft implantation model

ABSTRACTBackground: Freeze-dried and irradiated allograft bone (FIAB) is more easily impacted than fresh-frozen allograft bone (FAB), but has weaker incorporation efficiency. We combined FIAB with fresh autologous coagula to enhance donor-host incorporation after impaction during hip revision. Methods: Thirty adult male Sprague–Dawley (SD) rats were sacrificed for bone allograft harvesting, and nine male rats were subjected to ectopic bone allograft implantation. For each rat, the container on the left (study) side was filled with freeze-dried allograft bone powder and fresh autologous blood coagula, whereas the right (control) side was filled with freeze-dried allograft bone powder and physiological saline. The extent of angiogenesis (VEGFα) was investigated at postoperative weeks 1, 4, and 8. The deformability of the material was evaluated by performing a confined-impaction mechanical test. Results: At postoperative weeks 4 and 8, angiogenesis within FIAB on the left side was more pronounced than that on the right side. At postoperative week 1, the left side showed significantly higher VEGFα expression than that on the right side. The delta ratios of compression of the allografts were found to be influenced by bone height and impaction frequency, but not by stiffness or elastic modulus (EM). Conclusion: Supplementation with fresh autologous coagula promoted angiogenesis within the FIABs. Moreover, FIABs were equivalent to FABs in terms of deformability.

The relationship between fractional anisotropy value and tumor microarchitecture in late-stage rat glioma.

To explore the magnetic resonance diffusion tensor imaging (MR-DTI) features of in the late stage of Wistar rat C6 brain glioma, and the relationship between fractional anisotropy value and tumor microarchitecture. The concentration of more than 1.0×106/10μL glioma cells and complete medium were injected stereotactically into the right caudate nucleus of the experimental group (n=35) and control group (n=10), respectively. Conventional MRI, DTI, and enhanced T1WI scans were Performed using the GE Signa HD×3.0T MRI scanner about 3-4 weeks after implantation for the rats. Postprocessing was done using the DTI specific software Function Tool to gain FA image. Many ROIs were drawn avoiding hemorrhage, necrosis areas in tumor parenchyma, the value of FA was recorded. Each surviving rat brain was examined histologically using HE and immunohistochemical staining for VEGF and CD34. Pearson correlation analysis was used to determine the relationships between FA values and VEGF, MVD, cell density, respectively. A total of 35 tumor-bearing rats were confirmed the tumor formation by the subsequent MRI and pathological examination. The mean FA values of the tumor and the contralateral brain tissue were 0.17±0.03 and 0.31±0.05 respectively, and the difference was statistically significant (t=12.80, P<0.05). The mean FA value of grade III glioma (n=12) was 0.16±0.03, and the average FA value of grade IV glioma (n=23) was about 0.18±0.04. There was no significant difference between the two groups (t=1.92, P>0.05). FA value in the late stage of Wistar rat C6 brain glioma has significant positive correlation to VEGF, MVD, cell density. The correlation coefficients between FA and VEGF, MVD, and cell density were 0.67, 0.65 and 0.71 (P<0.05), respectively. The FA value of rat glioma tumor in the late stage can preoperatively provide an accurate, reliable and noninvasive imaging monitoring method to evaluate the microstructure of glioma (cell density, the extent of angiogenesis, fiber bundle integrity and tumor cell infiltration and so on), predict the biological behavior of the tumor and make out surgical plan.

Imaging angiogenesis using 68Ga-NOTA-PRGD2 positron emission tomography/computed tomography in patients with severe intracranial atherosclerotic disease

Angiogenesis is a critical compensation route, which has been demonstrated in the brain following ischemic stroke; however, few studies have investigated angiogenesis in chronic intracranial atherosclerosis disease (ICAD). We used 68Ga-NOTA-PRGD2 positron emission tomography/computed tomography based imaging to detect angiogenesis in chronic ICAD and to explore the factors that may have affected it. A total of 21 participants with unilateral severe chronic ICAD were included in the study. Of the 21 participants, 19 were men; the mean (SD) age was 52 (15) years. In 18 participants, we observed elevated 68Ga-NOTA-PRGD2 uptake in the peri-infarct, subcortical, and periventricular regions of the lesioned side, with a higher 68Ga-NOTA-PRGD2 SUVmax compared to that in the contralateral hemisphere (0.15 vs. 0.06, p=0.001). The 18F-FDG PET SUVmax was significantly lower on the lesioned side (11.28 vs. 13.92, p=0.001). Subgroup analyses revealed that the recent group (<6 months) had a higher lesion-to-contralateral region ratio SUVmax than the remote group (>6 months) (6.73 vs. 2.36, p<0.05). Our results provide molecular imaging evidence of angiogenesis in patients with severe chronic ICAD. Furthermore, the extent of angiogenesis in chronic ICAD may be affected by the post-qualified event time interval, and not by infarction itself or the severity of the arterial lesion.

Abstract OT2-02-03: Pilot study of zirconium-89 bevacizumab positron emission tomography for imaging angiogenesis in patients with inflammatory breast carcinoma receiving preoperative chemotherapy

Abstract Background: Inflammatory breast cancer (IBC) continues to have a poor prognosis despite standard tri-modality treatment with chemotherapy, mastectomy and radiation. Current methods of assessing primary tumor response (i.e., clinical exam and breast magnetic resonance imaging [MRI]) are limited for distinguishing residual tumor from responsive disease because of persistent morphologic changes in the breast. Therefore, the inability to accurately assess tumor response during treatment often results in the continuation of ineffective systemic chemotherapy until definitive pathologic evaluation at mastectomy. IBC has a highly angiogenic phenotype which is believed to play a role in this tumor's aggressiveness. The novel radiotracer Zirconium-89 (89Zr)-bevacizumab was developed for imaging tumor angiogenesis with PET. We hypothesize that, as an imaging biomarker of angiogenesis, 89Zr-bevacizumab-PET/CT is a more specific noninvasive functional imaging modality for detecting the presence of tumor angiogenesis compared to current diagnostic methods and will serve as a predictor of response to therapy in patients (pts) with IBC. Methods: Pts with newly diagnosed HER2neg IBC who will receive preoperative chemotherapy are eligible for this pilot study. 89Zr-bevacizumab-PET/CT, breast MRI and FDG-PET/CT are performed before, after 2 cycles, and at the completion of preoperative therapy. Biopsies of primary IBC tumors are obtained prior to and after 2 cycles of preoperative therapy. At the completion of preoperative therapy, pts proceed to mastectomy or biopsy if ineligible to proceed to mastectomy based on current standards for assessing primary tumor response, i.e., clinical exam, breast MRI and lack of systemic progression. At the time of mastectomy, standard evaluation of the surgical specimen will determine pathologic response of IBC to preoperative chemotherapy. A research sample will be collected if residual cancer is present at the time of mastectomy for histologic evaluation of tumor angiogenesis. Objectives/Correlatives: The primary objective is to determine feasibility of 89Zr-bevacizumab-PET/CT imaging in pts with IBC. The primary endpoint is assessment of radiolabeling of chelated bevacizumab and number of successfully acquired 89Zr-bevacizumab-PET/CT scans. Correlative studies will be performed on IBC tissue to assess extent of angiogenesis including microvessel density, vessel diameter, vascular pericyte coverage and tumor VEGF levels. Secondary objectives are: 1) To determine if 89Zr-bevacizumab accumulation in primary IBC tumors correlates with the extent of angiogenesis determined by correlative analysis on IBC tissue; 2) To assess the predictive value of 89Zr-bevacizumab-PET/CT after 2 cycles and at the end of preoperative therapy for determining pathologic response at mastectomy as given by residual cancer burden. Statistics: This is an accrual, not statistical based, feasibility justification. Planned sample size is 10 in order to make a preliminary statement about feasibility and ability for 89Zr-bevacizumab-PET/CT to serve as a surrogate in vivo biomarker of tumor angiogenesis and response to preoperative chemotherapy. Clinical Trial Information: NCT01894451. Citation Format: Jacene HA, Overmoyer B, Schlosnagle EJ, Abbott A, Yeh E, Paolino J, Goel S, Culhane A, Bellon JR, Nakhlis F, Hirshfield-Bartek J, Van den Abbeele A. Pilot study of zirconium-89 bevacizumab positron emission tomography for imaging angiogenesis in patients with inflammatory breast carcinoma receiving preoperative chemotherapy [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr OT2-02-03.

Abstract A33: The implication of patient derived tumor cell (PDTC) tested/screened with novel microtube array membrane (MTAM)-based hollow fiber assay (HFA).

Abstract Background: Previously we have demonstrated the novel microtube array membrane (MTAM) can serves as an excellent substrate for a rapid, in vivo anti-cancer drug screening assay based on the hollow fiber assay (HFA), with higher cell-drug sensitivity, cell-host interaction, plus the clear angiogenesis, owing to its unique structural characteristics. In current study, the patient derived tumor cells (PDTC) were subjected to MTAM/X based screening platform. Patient derived colon cancer sample was treated and loaded into MTAM, studied first in cell growth and characterization, and later the cell toxicity by several representative cancer drugs, both in vitro and in vivo. The goal of this study is to explore the potential of utilizing MTAM/X with PDX for rapid, reliable, lower cost personalized anti-cancer drug selection platform. Materials and Methods: Nano-porous PLLA MTAMs (npMTAM) were fabricated via a co-axial electrospinning and characterized morphologically first, then mechanical and permeation properties were determined. The nano-porous microstructure was also characterized by porosimeter. PTDC (colon cancer, 0.5 cm3) was obtained surgically and treated with enzyme-containing medium, homogenized before loaded into npMTAM at 105-106 cell per sample. The subcutaneous implantation of these MTAMs were conducted with 4 MTAMs per model (BALB/c) one day before the drug treatment. Regiments used according to the recommended dosage were cisplatin, 5 FU and Erbitux. In vitro and in vivo PDTC growth within MTAM were determined via MTT assay. The in vivo drug cytotoxicity towards PDTC was then determined by MTT in a 9-day period, in the meantime, the supportive results of angiogenesis was characterized via imaging process. Results: Nano-porous PLLA MTAMs were successfully prepared with a tube wall thickness of 2-3 microns and pore size of 100-200 nm. PDTC (colon cancer) was loaded into npMTAM within 2 hours after surgical collection. The in vitro and in vivo growth of PDTC in npMTAM was observed clearly in a two weeks period. Upon the administration of 5 FU, Cisplatin and Erbitux to the test model, cell growth was altered, however in different fashion. 5FU show early cell cytotoxicity, however, loss its inhibition capability afterwards. Erbitux showed no sign of inhibition. Finally greatest inhibition of this particular patient tumor was found with cisplatin. Extent of angiogenesis was found to be in consist with MTT data. The overall time needed to generate the final results is within 2 weeks. Conclusions: Testing PDTC in vivo within npMTAM based assay (PDXiMTAM), we demonstrated the feasibility of in vivo personalized cancer drug selection platform can be achieved in a reasonable time periods of 2 weeks. Selection from a group of four regiments, cisplatin demonstrated its highest cytotoxicity towards this specific tumor. This will be a very practical assay in clinical setting to identify most effective drug at personal level. Our results therefore suggest that such assay could be further developed in timely treatment selection. A double blind, cohort clinical trial of 60 patients with colon cancer is currently ongoing to validate PDXiMTAM. Citation Format: Po-Li Wei, Chia-Shiuan Tseng, Chien-Chung Chen, Chien-Jin Chiu, George Hsiao. The implication of patient derived tumor cell (PDTC) tested/screened with novel microtube array membrane (MTAM)-based hollow fiber assay (HFA).. [abstract]. In: Proceedings of the AACR Special Conference: Patient-Derived Cancer Models: Present and Future Applications from Basic Science to the Clinic; Feb 11-14, 2016; New Orleans, LA. Philadelphia (PA): AACR; Clin Cancer Res 2016;22(16_Suppl):Abstract nr A33.

Macrophage Recruitment and Polarization During Collateral Vessel Remodeling in Murine Adipose Tissue.

During autologous flap transplantation for reconstructive surgeries, plastic surgeons use a surgical pre-treatment strategy called "flap delay," which entails ligating a feeding artery into an adipose tissue flap 10-14 days prior to transfer. It is believed that this blood flow alteration leads to vascular remodeling in the flap, resulting in better flap survival following transfer; however, the structural changes in the microvascular network are poorly understood. Here, we evaluate microvascular adaptations within adipose tissue in a murine model of flap delay. We used a murine flap delay model in which we ligated an artery supplying the inguinal fat pad. Although the extent of angiogenesis appeared minimal, significant diameter expansion of pre-existing collateral arterioles was observed. There was a 5-fold increase in recruitment of CX3CR1(+) monocytes to ligated tissue, a threefold increase in CD68(+) /CD206(+) macrophages in ligated tissue, a 40% increase in collateral vessel diameters supplying ligated tissue, and a 6-fold increase in the number of proliferating cells in ligated tissue. Our study describes microvascular adaptations in adipose in response to altered blood flow and underscores the importance of macrophages. Our data supports the development of therapies that target macrophages in order to enhance vascular remodeling in flaps.

Relationship of Baseline Tumor Angiogenesis with Kinetics of Inflammatory Markers in DLBCL

IntroductionAngiogenesis is one of the central dogmas in growth and progression of a malignant tumor including malignant lymphoma. Lymphoma is a tumor originating from immune cells and lymphoid malignancies and it can alter normal immune function. However, nature of the immune dysfunction is not well defined. Inflammatory mediators acting through Th1/Th2 cytokines and growth factors secreted by the infiltrating inflammatory cells are known to have both direct and indirect angiogenic effects on endothelial cells.Whether tumor angiogenesis in lymphoma patients is associated with alteration in inflammatory cytokines is an unexplored area.Whether extent of angiogenesis at baseline and elevation of levels of biomarkers in the serum have any bearing on chemotherapy response in a patient of B-NHL remains an unanswered question.MethodsForty nine cases of de novo DLBCL with available formalin fixed paraffin embedded (FFPE) block, serum (stored at -80˚C)and IPI were reviewed using the diagnostic criteria defined in the Revised European-American Classification of Lymphoid Neoplasm's.BD Pharmigen™cytometric bead analysis (CBA) Human Th1/Th2 Cytokine Kit II (Catalog No. 560484) was used to quantitateInterleukin-2 (IL-2), Interleukin-4 (IL-4), Interleukin-6 (IL-6), Interleukin-10 (IL-10), Tumor Necrosis Factor (TNF-α), and Interferon-γ (IFN-γ) protein levels against internal standard controls. BD FCAP ArrayTM software was used to analyze all the cytokines levels respectively. Baseline angiogenesis in tumor was assessed by histopathologic examination for micro vessel density. Microvessel density was examined using CD34 antibody (clone QBEnd 10, Dako, Denmark), an endothelial cell marker. Vascular "Hot Spots" were identified at low power and the visual analog system was used for counting at 40X in at least five independent microscopic fields per tissue section. The mean of five fields was calculated and divided by the field area (1 HPF=0.19 mm2) to obtain the density count in mm2. Precautions were taken to count vessels at the center of the tumor and to avoid the periphery of the tumor to obtain true representation of tumor vasculature. Median value was calculated for the continuous data and CD34, IL-6, IL-10, IL-4, IL-2, IL-17, TNF-α, IFN-γ divided into categorical variables based on median value. Kaplan-Meier method was used to estimate event-free survival (EFS) distribution.Cytokine profile and microvessel density were correlated with EFS for identification of prognostic marker. Informed consent was taken from all the patients enrolled in the study in accordance with IEC, PGIMER guidelines.ResultsForty nine DLBCL cases in the study included thirty (61%) males and nineteen (39%) females (male/female, 1.6:1). The median age of patients was 56 years (range, 17 - 80 years). Stage I/II were seen in 40% patients while stage III/IV were seen in 60% patients. Fifty-four patients had extranodal disease. Forty five, 15 and 40% patients had low, intermediate and high risk IPI respectively. All but 3 patients were treated with RCHOP based regimen. Remaining 3 patients 2 received bendamustine with rituximab while one recevied only CHOP. CR rate was 58.8% while ORR was 70%. At the time of analysis three patients had died. On univariate analysis, IL-10, a cytokine of TH2 response, was identified as a promising prognostic factor for EFS (p<0.05). However, association of levels of IL-6, IL-2, IL-4, TNF-α, IFN-γ, and IL-17 with EFS was not statistically significant. There was no statistically significant relation between any of the tested cytokine levels and chemotherapy response rates. Median EFS for patients with high IL10 level was 8.2 months. While median value of EFS for patients with low IL2 levels was not reached till the time of data analysis. Microvessel density was an independent predictor of EFS (p=0.024).ConclusionWe conclude that high micro vessel density and high IL10 levels are associated with poorer event free survival in DLBCL patients. [Display omitted] [Display omitted] [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Chitosan leads to downregulation of YKL‐40 and inflammasome activation in human macrophages

Chitosan, the deacetylated derivative of chitin, is used as biomaterial in diverse settings. It is also found on pathogens and can be proinflammatory. Shorter derivatives of chitosan can be generated chemically or enzymatically, chitosan oligosaccharides (ChOS). There is variation in the chemical composition of ChOS, including size distribution, but in general, they have been described as inert or anti-inflammatory. Active human chitinases can cleave chitin and chitosan, while inactive chitinases bind both but do not cleave. Both active and inactive chitinases have important roles in the immune response. The inactive chitinase YKL-40 is expressed highly during inflammation and has been proposed as a marker of poor prognosis. YKL-40 acts as a negative regulator of the inflammasome and as a positive regulator of angiogenesis. Levels of YKL-40 can therefore regulate levels of inflammation, the extent of angiogenesis, and the process of inflammation resolution. This study shows that chitosan leads to reduced secretion of YKL-40 by primary human macrophages and that this is concomitant with inflammasome activation. This was most pronounced with a highly deacetylated ChOS. No effect on the secretion of the active chitinase Chit-1 was detected. Smaller and more acetylated ChOS did not affect YKL-40 levels nor inflammasome activation. We conclude that this effect on the levels of YKL-40 is a part of the proinflammatory mechanisms of chitosan and its derivatives.

Abstract 9409: Aging Inhibits Angiogenic Response in a Rat Model of Hindlimb Ischemia: A HUR-VEGF Dependent Mechanism

Introduction: Human antigen R (HUR) is a RNA stablilizer and its expression decressed in aging organism, however, its downstream signal pathways remain modest clarified. Here, we examined whether HUR plays a role in angiogenic response using an aging rat model of hindlimb ischemia. Methods and Results: Male Sprague-Dawley rats were divided into 2 groups: the young group (12 week-old) and the aging group (96 week-old). The left femoral artery of all rats were excised, and the extent of angiogenesis and collateral vessels in the ischemic limb were examined for 2 weeks. At postoperative day 14, aging rats exhibited impaired angiogenic action (skin temperature, capillary density and angiography) and decreased angiogenic factor expressions (vascular endothelial growth factor [VEGF], hypoxic inducible factor-1α and nitric oxide [NO]) in ischemic muscles. The protein expression of HUR as well as endothelial nitric oxide synthetase (eNOS) phosphorylation were significantly inhibited in aging rats as well. In vitro, we applied anti-HUR small interfering RNA to transfect human umbilical vein endothelial cells (HUVECs). The results showed that transfected HUVECs exhibited decreased the capacities of VEGF/NO production, tube formation and apoptotic resistence compared with control. Conclusions: Our results domenstrated that the down-regulation of HUR plays a key role in aging-related poor angiogenic response.

Exploration of the Angiogenic Potential of Honey

Aims: The present study was conducted to confirm the angiogenic potential of honey using Chick Chorioallantoic Membrane (CAM), an in ovo model and to study its effect on Vascular Endothelial Growth Factor (VEGF) expression in the CAM tissue. Attempts were also made to identify the probable active constituents present in honey that contributed to its angiogenic potential. Methodology: Honey was evaluated over concentrations ranging from 0.015 to 25% v/v and the extent of angiogenesis was quantified using stereomicroscopy. VEGF expression at transcript level was determined by RT-PCR. Erythropoietin and Heparin were used as positive and negative controls respectively. Four known constituents of honey viz., Glucose, Proline, Vitamin C and Hydrogen peroxide were tested by biochemical methods. Results: New blood formation was seen at all the concentrations tested, however the proangiogenic effect was greater at lower concentrations. These results were significantly greater than that seen with erythropoietin, the positive control. VEGF mRNA expression in CAM tissue also demonstrated similar findings. Among the constituents tested, Vitamin C and Hydrogen peroxide were observed to be associated with the angiogenic effect of honey. Conclusion: The study thus confirms the pro-angiogenic potential of honey at low Original Research Article British Journal of Pharmaceutical Research, 4(4): 477-489, 2014 478 concentrations. This effect is probably due to the presence of Hydrogen peroxide and Vitamin C and is mediated via alteration in VEGF expression. .

IL-17A Stimulates the Progression of Giant Cell Tumors of Bone

Giant cell tumors of bone (GCTB) exhibit aggressive bone lytic behavior. Studies have shown that interleukin 17A (IL-17A) is involved pathologic bone resorption in various skeletal disorders. Thus, we have investigated the role of IL-17A in GCTBs. We evaluated the progression of GCTBs using Campanacci grading and Enneking staging systems in 74 patients with GCTB. The expression of IL-17A and the IL-17A receptor A (IL-17RA) was assessed in GCTB tissues and in both multinucleated giant cells (MNGC) and stromal cells cultured in vitro using immunostaining and reverse transcription PCR (RT-PCR). The effects of IL-17A on the osteolytic activity of the MNGCs and the proliferation of the stromal cells were investigated using the "pit" formation and MTT assays, respectively. The effects of IL-17A on the expression of proosteolytic factors were examined in primary cultured MNGCs and stromal cells using RT-PCR, Western blotting, and gene expression microarrays. In GCTBs, we detected abundant levels of IL-17A, which were associated with tumor extension and grade. IL-17A is predominantly produced by MNGCs, whereas IL-17RA is expressed by both MNGCs and stromal cells in GCTBs. In the MNGCs, the IL-17A increased the mRNA expression of IL-17A and proosteolytic enzymes, and also enhanced osteolytic ability. In the stromal cells, the IL-17A stimulated cellular proliferation and the expression of proosteolytic factors, including RANKL through myc and STAT3, respectively. In addition, IL-17A stimulated in vivo tumor growth and the extent of angiogenesis in GCTBs. IL-17A stimulates the progression of GCTBs and might represent a useful candidate marker for progression and as a therapeutic target for GCTBs.