Human esophageal cancer endothelial cells increase tumor growth by incorporating with mouse endothelium

Inhibition of glycolytic activator PFKFB3 suppresses tumor growth and induces tumor vessel normalization in hepatocellular carcinoma

Glycolysis emerges as a new therapeutic target for malignancies. The inhibition of glycolytic activator, PFKFB3, repairs tumor endothelial cell function, and normalizing the tumor microenvironment. We aimed to investigate the significance of PFKFB3 in HCC, and the effects of the PFKFB3 inhibitor, PFK15, in HCC tumor cells and tumor endothelial cells. Double immunofluorescent staining of PFKFB3 and CD31 in HCC tissues revealed that high PFKFB3 expression in both tumor cells and tumor endothelial cells was significantly correlated with poor prognosis. Multivariate analysis identified PFKFB3 expression as an independent prognostic factor. PFK15 suppressed proliferation of HCC cell line and tumor endothelial cells in vitro. In a subcutaneous tumor model of the HCC cell line with tumor endothelial cells, PFK15 suppressed tumor growth and induced apoptosis. Moreover, PFK15 treatment induced tumor vessel normalization, decreasing vessel diameter with pericyte attachment and improving vessel perfusion. High PFKFB3 expression in both tumor cells and tumor endothelial cells was identified as a novel prognostic marker in HCC. Targeting PFKFB3 via PFK15 might be a promising strategy for suppressing tumor growth and inducing tumor vessel normalization.

Abnormal blood vessels formed by human liver cavernous hemangioma endothelial cells in nude mice are suitable for drug evaluation

Cavernous hemangioma is vascular malformation with developmental aberrations. It was assumed that the abnormality of endothelial cells contributed greatly to the occurrence of cavernous hemangioma. In our previous study, we have found distinct characteristics of endothelial cells derived from human liver cavernous hemangioma (HCHEC). Here, we reported the abnormal vascular vessels formed by primary HCHEC in nude mice and that the drug podophyllotoxin can destroy HCHEC in vitro and in vivo. HCHEC was isolated from a human liver cavernous hemangioma specimen, and the HCHEC generated a red hemangioma-like mass 7 days after subcutaneously co-inoculating HCHEC and human liver cancer cells (Bel-7402) in nude mice. Lentiviral expression of GFP and immunohistochemistry for human CD31 was used to confirm that the HCHEC formed the blood vessels in nude mice. And the pathological features of vascular vessels formed by HCHEC were very similar to clinical cavernous hemangioma. In addition, by MTT assay, the drug podophyllotoxin was found inhibiting HCHEC viability, and by TUNEL and DNA ladder assays, podophyllotoxin was found inducing apoptosis of HCHEC. Moreover, podophyllotoxin was also effective for destroying the abnormal vascular vessels in the hemangioma-like mass in nude mice. In summary, the HCHEC can form abnormal blood vessels in nude mice, and we can evaluate drugs for cavernous hemangioma by using HCHEC in vitro and in vivo.

Antibody library-based tumor endothelial cells surface proteomic functional screen reveals migration-stimulating factor as an anti-angiogenic target

Angiogenesis is critical for cancer development and metastasis. Here we have employed a functional antibody library-based proteomic screen to identify proteins that participate in and might be used as therapeutic targets for tumor-related angiogenesis. Mice were immunized with human esophageal cancer endothelial cells (HECEC). The antibody library was established with the mouse spleen cells the serum of which had most anti-angiogenic effect. Monoclonal antibodies were subjected to an immunoreactive and functional screen and monoclonal antibodies that reacted strongly with cell surface antigens of HECECs and influenced their behavior were selected. Antigens that recognized by the antibodies were obtained by immunoprecipitation and then identified by mass spectrometry analysis. Migration-stimulating factor (MSF), the antigen of 1D2 antibody was identified using this approach. Further studies demonstrated that the 1D2 antibody suppressed MSF-effected migration and adhesion of HECECs on fibronectin matrix. Biodistribution assay showed that MSF targeting antibody 1D2 could specifically home to the xenograft with humanized blood vessel. Targeting treatment with 1D2 antibody significantly suppressed tumor growth through inhibition of human tumor-related angiogenesis. These results indicate that the functional antibody library-based proteomic screen can successfully identify proteins that involved in tumor-related angiogenesis and MSF may be a target for the anti-angiogenic treatment of the esophageal cancer.

5-Aza-2'-deoxycytidine increases the expression of anti-angiogenic vascular endothelial growth factor 189b variant in human lung microvascular endothelial cells

Vascular endothelial growth factor (VEGF) is involved in angiogenesis, growth, and tumour cell metastasis. VEGF is expressed as alternative splice variants, which exhibit angiogenic and anti-angiogenic properties. We determined the effect of 5-Aza-2'-deoxycytidine (5-dAzaC) DNA methyltransferase (DNMTs) inhibitor on angiogenic and anti-angiogenic VEGF variants expression in immortalized human lung microvascular endothelial cells (HLMEC). Employing reverse transcription, real-time quantitative PCR (RQ-PCR), and Western blot analysis, we determined that 5-dAzaC decreased VEGF(121a) and VEGF(165a) angiogenic, and VEGF(121b) and VEGF(165b) anti-angiogenic variants expression in HLMEC. However, this DNMTs inhibitor significantly increases expression of VEGF(189b) anti-angiogenic variant transcript and protein in HLMEC. Our results suggest that the DNMTs activity may have an influence on the expression of angiogenic and anti-angiogenic VEGF variants in human lung microvascular endothelial cells.