Emodin suppresses alkali burn-induced corneal inflammation and neovascularization by the vascular endothelial growth factor receptor 2 signaling pathway.

OBJECTIVE: To investigate the effects of emodin on alkali burn-induced corneal inflammation and neovascularization. METHODS: The ability of emodin to target vascular endothelial growth factor receptor 2 (VEGFR2) was predicted by molecular docking. The effects of emodin on the invasion, migration, and proliferation of human umbilical vein endothelial cells (HUVEC) were determined by cell counting kit-8, Transwell, and tube formation assays. Analysis of apoptosis was performed by flow cytometry. CD31 levels were examined by immunofluorescence. The abundance and phosphorylation state of VEGFR2, protein kinase B (Akt), signal transducer and activator of transcription 3 (STAT3), and P38 were examined by immunoblot analysis. Corneal alkali burn was performed on 40 mice. Animals were divided randomly into two groups, and the alkali-burned eyes were then treated with drops of either 10 µM emodin or phosphate buffered saline (PBS) four times a day. Slit-lamp microscopy was used to evaluate inflammation and corneal neovascularization (CNV) in all eyes on Days 0, 7, 10, and 14. The mice were killed humanely 14 d after the alkali burn, and their corneas were removed and preserved at －80 ℃ until histological study or protein extraction. RESULTS: Molecular docking confirmed that emodin was able to target VEGFR2. The findings revealed that emodin decreased the invasion, migration, angiogenesis, and proliferation of HUVEC in a dose-dependent manner. In mice, emodin suppressed corneal inflammatory cell infiltration and inhibited the development of corneal neovascularization induced by alkali burn. Compared to those of the PBS-treated group, lower VEGFR2 expression and CD31 levels were found in the emodin-treated group. Emodin dramatically decreased the expression of VEGFR2, p-VEGFR2, p-Akt, p-STAT3, and p-P38 in VEGF-treated HUVEC. CONCLUSION: This study provides a new avenue for evaluating the molecular mechanisms underlying corneal inflammation and neovascularization. Emodin might be a promising new therapeutic option for corneal alkali burns.

Evaluation of Microwave Ablation in 4T1 Breast Tumor by a Novel VEFGR2 Targeted Ultrasound Contrast Agents.

OBJECTIVES: A novel ultrasound contrast agent (UCA) VEGFR2-targeting iron-doped silica (SiO2) hollow nanoparticles (VEGFR2-PEG-HSNs-Fe NPs) was prepared and applied in microwave ablation for breast cancer to investigate its value in the evaluation of effectiveness after tumor ablation. METHODS: VEGFR2-PEG-HSNs-Fe NPs were prepared by using nano-SiO2, which was regarded as a substrate and etched by ferrous acetate, and then modified with anti-VEGFR2 antibody. Laser confocal microscope and flow cytometry were used to observe its main physicochemical properties, and biological safety was also investigated. After the xenograft tumor was treated with microwave ablation, the extent of perfusion defect was evaluated by ultrasound by injecting VEGFR2-PEG-HSNs-Fe NPs. RESULTS: The average particle size of VEGFR2-PEG-HSNs-Fe was 276.64 ± 30.31 nm, and the surface potential was -13.46 ± 2.83 mV. In vitro, the intensity of ultrasound signal increased with UCA concentration. Good biosafety was performed in in vivo and in vitro experiments. The enhanced ultrasound signal was detected in tumors after injection of VEGFR2-PEG-HSNs-Fe NPs, covering the whole tumor. The lesions, which were incompletely ablated, presented as contrast agent perfusion at the periphery of the tumor, and contrast enhanced ultrasound (CEUS) was performed again after complementary ablation. It was confirmed that all the lesions were completely ablated. CONCLUSION: Nano-targeted UCAs VEGFR2-PEG-HSNs-Fe NPs had good biosafety and ability of specific imaging, which might be used as a contrast agent in CEUS to evaluate the efficacy of tumor ablation.

Apatinib combined with concurrent chemoradiotherapy in patients with subglottic small cell carcinoma: a case report.

Subglottic small cell carcinoma (SSMCC) is a rare type of neoplasm, meaning that laryngeal cancer guidelines in several countries, including the National Comprehensive Cancer Network (NCCN) guidelines, do not include treatment principles for SSMCC. Angiogenesis is an established factor in tumor initiation, growth, and dissemination. Apatinib mesylate, an orally administered drug, is a novel inhibitor of vascular endothelial growth factor receptor-2, a key mediator of angiogenesis, and has been shown to be safe and efficacious in the treatment of certain types of malignant tumors. To the best of our knowledge, there are few reports on the treatment of SSMCC with apatinib combined with concurrent chemoradiotherapy. In the present report of SSMCC in a 64-year-old woman, oral apatinib was given daily at a dose of 250 mg in combination with concurrent chemoradiotherapy; the only toxicities reported were mild leukopenia and finger numbness. Clear and rapid efficacy was observed with the disappearance of the tumor mass. Our findings indicate that apatinib combined with concurrent chemoradiotherapy may be effective in patients with SSMCC, with adverse reactions within the manageable range, thus representing an additional treatment option for this type of malignancy.

Development of small-molecule tropomyosin receptor kinase (TRK) inhibitors for NTRK fusion cancers.

Tropomyosin receptor kinase A, B and C (TRKA, TRKB and TRKC), which are well-known members of the cell surface receptor tyrosine kinase (RTK) family, are encoded by the neurotrophic receptor tyrosine kinase 1, 2 and 3 (NTRK1, NTRK2 and NTRK3) genes, respectively. TRKs can regulate cell proliferation, differentiation and even apoptosis through the RAS/MAPKs, PI3K/AKT and PLCγ pathways. Gene fusions involving NTRK act as oncogenic drivers of a broad diversity of adult and pediatric tumors, and TRKs have become promising antitumor targets. Therefore, achieving a comprehensive understanding of TRKs and relevant TRK inhibitors should be urgently pursued for the further development of novel TRK inhibitors for potential clinical applications. This review focuses on summarizing the biological functions of TRKs and NTRK fusion proteins, the development of small-molecule TRK inhibitors with different chemotypes and their activity and selectivity, and the potential therapeutic applications of these inhibitors for future cancer drug discovery efforts.

PD-L1 and VEGFR-2 expression in synchronous metastatic renal cell carcinoma treated with targeted therapy following cytoreductive nephrectomy.

OBJECTIVES: Few studies have independently investigated the population of patients with synchronous metastatic renal cell carcinoma (smRCC). In this study, we evaluated programmed death protein-ligand 1 (PD-L1) and vascular endothelial growth factor receptor 2 (VEGFR-2) expression in primary tumor tissue of smRCC. METHODS: A total of 96 patients with smRCC who were treated with cytoreductive nephrectomy followed by targeted therapy from January 2006 to January 2013 were identified. PD-L1 and VEGFR-2 expression were evaluated by immunohistochemistry. Kaplan-Meier and Cox methods were used for analysis. RESULTS: PD-L1 and VEGFR-2 protein immunopositivity were observed in 39.6% (38 of 96) and 58.3% (56 of 96) of patients, respectively. A significant correlation was detected between VEGFR-2 and PD-L1 expression (P = 0.030). Based on PD-L1 and VEGFR-2 expression, patients with intermediate-risk disease (n = 63) were divided into 4 subgroups including patients who were PD-L1 (+) VEGFR-2 (+) (n = 21), PD-L1 (+) VEGFR-2 (-) (n = 11), PD-L1 (-) VEGFR-2 (+) (n = 15) and PD-L1 (-) VEGFR-2 (-) (n = 16). Compared to the PD-L1 (-) VEGFR-2 (+), PD-L1 (+) VEGFR-2 (+) and PD-L1 (-) VEGFR-2 (-) groups, patients in the PD-L1 (+) VEGFR-2 (-) group had shorter progression-free survival (median, 9.0 vs. 20.0, 16.0 and 15.5 months, P < 0.05) and overall survival (median, 14.0 vs. 33.0, 24.0 and 26.5 months, P < 0.05). CONCLUSIONS: Intermediate-risk smRCC patients with PD-L1-positive and VEGFR-2-negative expression who were treated with targeted therapy following cytoreductive nephrectomy had poor prognoses. We suggest that other treatments beyond sunitinib or sorafenib may be explored in this subgroup.

Apatinib as an alternative therapy for advanced hepatocellular carcinoma.

Angiogenesis plays an important role in the occurrence and development of tumors. Registered tyrosine kinase inhibitors targeting vascular endothelial growth factor reduce angiogenesis. Apatinib, a tyrosine kinase inhibitor, can specifically inhibit vascular endothelial growth factor receptor 2, showing encouraging anti-tumor effects in a variety of tumors including advanced hepatocellular carcinoma (HCC). This article intends to review the clinical research and application prospects of apatinib in the field of HCC.

Cultivated Orostachys japonicus extract inhibits VEGF-induced angiogenesis via regulation of VEGFR2 signaling pathway in vitro and in vivo.

ETHNOPHARMACOLOGICAL RELEVANCE: Orostachys japonicus A. Berger (O. japonicus), so-called Wa-song in Korea, a traditional food and medicine that grows on mountain rocks and roof tiles. Wa-song containing various phenolic compounds have been reported as a medicinal plant for prevention of fibrosis, cancer, inflammation, and oxidative damage. AIM OF THE STUDY: The present study was designed to examine the anti-angiogenic effects of cultivated Orostachys japonicus 70% ethanol extract (CE) in vascular endothelial growth factor (VEGF)-stimulated human umbilical vein endothelial cells (HUVECs). MATERIALS AND METHODS: CE was prepared with 70% ethanol. HUVECs, rat aortic rings, and matrigel plug in mice were treated with CE (10-20 µg/mL) and VEGF (20-50 ng/mL), and the anti-angiogenic activities of CE were analyzed by SRB, wound healing, trans-well invasion, capillary-like tubule formation, rat aortas, Western blot, and matrigel plug assay. Phenolic compounds in CE were analyzed using a high-performance liquid chromatography (HPLC)-PDA system. RESULTS: Treatment of CE (10-20 µg/mL) markedly suppressed proliferation of HUVECs in the presence (from 136.5% to 112.2%) or absence of VEGF (from 100.0% to 92.1%). The proliferation inhibitory effect of CE was caused by G0/G1 cell cycle arrest, and the decrease of CDK-2, CDK-4, Cyclin D1 and Cyclin E1. Furthermore, CE treatment showed significant angiogenesis inhibitory effects on motility, invasion and micro-vessel formation of HUVECs, rat aortic rings and subcutaneous matrigels under VEGF-stimulation condition. In HUVECs, CE-induced anti-angiogenic effect was regulated by inhibition of the PI3K/AKT/mTOR, MAPK/p38, MAPK/ERK, FAK-Src, and VEGF-VEGFR2 signaling pathways. CONCLUSION: This study demonstrated that CE might be used as a potential natural substance, multi-targeted angiogenesis inhibitor, functional food material.

Effects of Huatan Tongluo decoction on vascular endothelial growth factor receptor 2 expression in synovial tissues of rats with collagen-induced arthritis.

OBJECTIVE: To determine the therapeutic effect and potential mechanism of Huatan Tongluo decoction on rats with collagen-induced arthritis. METHODS: Forty specific pathogen-free Wistar rats were selected, and 10 were randomly selected as the control (group 1). The remaining rats were injected intradermally with emulsified type II bovine collagen at the tail base and back, followed by a booster 7 d post first immunization. After establishing collagen-induced arthritis (CIA), rats were randomly divided into three groups (n = 10). The rats were treated orally for 30 d as follows: group 1, saline; group 2, model (saline); group 3, tripterygium polyglycoside (TP; 7.81 mg/kg, positive control); group 4, Huatan Tongluo decoction (HTTL; 7.5 g/kg). Body weight, ankle swelling and arthritis index were measured over the course of the study. The rats were sacrificed 30 d after treatment. Morphological changes in the synovium were observed by hematoxylin and eosin staining. Pannus formation and synovial thickness in the left ankle were observed by color Doppler ultrasoundVascular endothelial growth factor (VEGF) and VEGFR2 protein levels were measured by immunohistochemistry. VEGF/VEGFR2 mRNA levels were measured by real-time quantitative polymerase chain reaction. RESULTS: Compared with the model group, a significantly lower arthritis index was observed in the positive control group (P < 0.05) and HTTL group (P < 0.01), after treatment. Both positive control and HTTL reduced intra-articular pannus formation and synovial thickening. Furthermore, VEGF mRNA, and VEGFR2 protein and mRNA levels were significantly downregulated (P < 0.05) in the treatment groups. CONCLUSION: Inhibition of the expression of VEGF and VEGFR2 in synovial tissues and the formation of pannus and synovial hyperplasia may be part of the mechanism of HTTL for relieving the symptoms of rheumatoid arthritis in CIA rats.

Antiarthritic Effects of Sorafenib in Rats with Adjuvant-Induced Arthritis.

Rheumatoid arthritis (RA) is a chronic inflammatory disease affecting the synovial membrane of joints. In this study, we aimed to investigate whether sorafenib exerts antiarthritic effects on RA in vivo. Adjuvant arthritis (AA) was induced (day 0) in male Sprague-Dawley rats by intradermal injection of 0.1 mL of complete Freund's complete adjuvant into the left hind paw. Sorafenib (10, 20, or 40 mg/kg/day) was administered intragastrically from day 10 to 24. Body weight, paw volume, synovial inflammation, and tumor necrosis factor alpha (TNF-α), interleukin-1ß (IL-1ß), IL-10, and IL-17 serum levels were detected. In addition, microvascular density (MVD) and the expression of vascular endothelial growth factor receptor 2 (VEGFR-2) and fibroblast growth factor receptor 1 (FGFR-1) in synovial tissues were analyzed. Our data revealed that sorafenib administration led to significant body weight gain in AA rats but suppressed paw swelling, synovial hyperplasia, and inflammatory infiltration. Furthermore, it decreased TNF-α, IL-1ß, and IL-17 serum levels and upregulated IL-10. MVD and VEGFR-2 and FGFR-1 expression in synovial tissues were significantly reduced. Thus, this study shows that sorafenib exerts anti-arthritic effects in AA rats and therefore has potential in RA treatment. Anat Rec, 301:1519-1526, 2018. © 2018 Wiley Periodicals, Inc.

Ramucirumab as second-line treatment in patients with advanced hepatocellular carcinoma: Japanese subgroup analysis of the REACH trial.

BACKGROUND: REACH evaluated ramucirumab in the second-line treatment of patients with advanced hepatocellular carcinoma. In the intent-to-treat population (n = 565), a significant improvement in overall survival (OS) was not observed. In patients with an elevated baseline α-fetoprotein (AFP) level (400 ng/mL or greater), an improvement in OS was demonstrated. An analysis of the Japanese patients in REACH was performed. METHODS: An analysis was performed with the subset of the intent-to-treat population enrolled in Japan (n = 93). RESULTS: The median OS was 12.9 months for the ramucirumab arm (n = 45) and 8.0 months for the placebo arm (n = 48) [hazard ratio (HR) 0.621 (95 % confidence interval (CI) 0.391-0.986); P = 0.0416]. The median progression-free survival was 4.1 months for the ramucirumab arm and 1.7 months for the placebo arm [HR 0.449 (95 % CI 0.285-0.706); P = 0.0004]. The objective response rates were 11 % for the ramucirumab arm and 2 % for the placebo arm (P = 0.0817). The grade 3 or higher treatment-emergent adverse events occurring in more than 5 % of patients with a higher incidence for the ramucirumab arm (n = 44) than for the placebo arm (n = 47) were ascites (7% vs 2 %), hypertension (7 % vs 2 %), and cholangitis (7 % vs 0 %). In patients with a baseline AFP level of 400 ng/mL or greater, the median OS was 12.9 months for the ramucirumab arm (n = 20) and 4.3 months for the placebo arm (n = 22) [HR 0.464 (95 % CI 0.232-0.926); P = 0.0263]. CONCLUSIONS: In the Japanese patients in REACH, ramucirumab treatment improved OS, including in patients with a baseline AFP level of 400 ng/mL or greater; improvements in progression-free survival and objective response rate were also demonstrated. The safety profile of ramucirumab was acceptable and well tolerated in Japanese patients. ClinicalTrials.gov identifier NCT01140347.

Experimental studies of a vaccine formulation of recombinant human VEGF antigen with aluminum phosphate.

CIGB-247 is a cancer vaccine that is a formulation of a recombinant protein antigen representative of the human vascular endothelial growth factor (VEGF) with a bacterially-derived adjuvant (VSSP). The vaccine has shown an excellent safety profile in mice, rats, rabbits, not-human primates and in recent clinical trials in cancer patients. Response to the vaccine is characterized by specific antibody titers that neutralize VEGF/VEGFR2 binding and a cytotoxic tumor-specific response. To expand our present anti-VEGF active immunotherapy strategies, we have now studied in mice and non-human primates the effects of vaccination with a formulation of our recombinant VEGF antigen and aluminum phosphate adjuvant (hereafter denominated CIGB-247-A). Administered bi-weekly, CIGB-247-A produces high titers of anti-VEGF IgG blocking antibodies in 2 mice strains. Particularly in BALB/c, the treatment impaired subcutaneous F3II mammary tumor growth and reduced the number of spontaneous lung macro metastases, increasing animals' survival. Spleen cells from specifically immunized mice directly killed F3II tumor cells in vitro. CIGB-247-A also showed to be immunogenic in non-human primates, which developed anti-VEGF blocking antibodies and the ability for specific direct cell cytotoxic responses, all without impairing the healing of deep skin wounds or other side effect. Our results support consideration of aluminum phosphate as a suitable adjuvant for the development of new vaccine formulations using VEGF as antigen.

Molecular ultrasound imaging using contrast agents targeting endoglin, vascular endothelial growth factor receptor 2 and integrin.

Expression levels of endoglin, αv integrin and vascular endothelial growth factor receptor 2 (VEGFR2) were investigated using targeted, contrast-enhanced ultrasonography in murine melanoma tumor models. Microvasculature and expression levels of biomarkers were investigated using specific contrast agents conjugated with biotinylated monoclonal antibodies. Ultrasound signal intensity from bound contrast agents was evaluated in two groups of mice: control mice and mice treated with sorafenib. Expression levels were analyzed by immunohistochemistry. Endoglin biomarkers were more highly expressed than αv integrin and VEGFR2. Endoglin decreased in the sorafenib group, whereas it tended to increase with time in the control group. Targeted ultrasound contrast agents may be used for non-invasive longitudinal evaluation of tumor angiogenesis during tumor growth or therapeutic treatment in preclinical studies. Endoglin protein, which plays an important role in angiogenesis, seems to be a target of interest for detection of cancer and for prediction of therapeutic efficacy.

Andrographolide inhibits tumor angiogenesis via blocking VEGFA/VEGFR2-MAPKs signaling cascade.

Traditional medicinal herb Andrographis paniculata is known to possess anti-tumor activity, and its potential active compound is the diterpenoid lactone andrographolide (ANGL). In this study, we have found that ANGL inhibits tumor growth in nude mice bearing xenografted Hep3B cancer cells, concomitant with a reduction in tumor vessel counts. ANGL inhibits vascular endothelial growth factor A (VEGFA)-induced angiogenic responses in vitro and neoangiogenesis in vivo. We also found that ANGL inhibits VEGFA-induced phosphorylation of vascular endothelial growth factor receptor 2 (VEGFR2) and its downstream targets such as the mitogen-activated protein kinases (MAPKs). ANGL interferes with the binding of VEGFA to VEGFR2, but has no effect on VEGFR2 kinase activity in vitro. Taken together, our results indicate that ANGL possesses anti-angiogenic activity which is mediated by preventing VEGFA-induced phosphorylation and activation of VEGFR2 and MAPKs. The present study indicates that ANGL can block tumor angiogenesis and therefore represents therapeutic potential for cancer treatment.