Upregulation of vasohibin-1 expression with angiogenesis and poor prognosis of hepatocellular carcinoma after curative surgery

Dynamic changes in vasohibin and nitric oxide signaling following surgical resection of head and neck squamous cell carcinoma

BACKGROUND

Angiogenesis is essential for tumor growth and metastasis, with various molecules, including vasohibin (VASH), nitric oxide (NO), and inducible nitric oxide synthase (iNOS), implicated in its regulation and potential prognostic value in oncology. However, their roles in modulating surgery-induced angiogenesis in head and neck squamous cell carcinoma (HNSCC) remain unclear. Therefore, the objective of the study was to assess the dynamic changes in VASH, NO, and iNOS levels in HNSCC patients undergoing surgical resection.

METHODS

We prospectively enrolled patients with histology-proven HNSCC who underwent surgical resection of primary tumors at the medical center between May and November 2021. Non-cancer controls were recruited to compare baseline biomarker levels with those of HNSCC patients. We measured preoperative and postoperative levels of VASH1 and VASH2 in plasma and leukocytes using enzyme-linked immunosorbent assays and Western blotting, NO using nitrate/nitrite colorimetric assays, and iNOS phosphorylation levels in leukocyte membranes using Western blotting.

RESULTS

Patients with HNSCC (n = 15) exhibited elevated baseline levels of VASH1, NO, and leukocyte-induced iNOS phosphorylation compared to non-cancer controls (n = 15). After tumor resection, plasma VASH1 levels were significantly downregulated (2233 ± 1464 pg·mL-1 vs. 2425 ± 1493 pg·mL-1, p = 0.0085), while plasma VASH2 levels remained unchanged in HNSCC patients. Similarly, VASH1 levels in leukocytes were reduced after surgery (0.85 ± 0.04 fold, p = 0.0068), while VASH2 levels did not change significantly. NO levels in plasma decreased significantly following surgery (0.29 ± 0.09 fold, p = 0.0001). Conversely, iNOS phosphorylation levels in leukocytes increased after surgery (1.52 ± 0.10 folds, p = 0.0024). The 3-year overall survival rates were 85.7% in patients with lower change folds of VASH1 in leukocytes, compared to 100.0% in those with higher change folds.

CONCLUSIONS

This study demonstrated that dynamic changes in VASH and NO signaling following tumor resection could serve as a potential indicator of tumor angiogenesis. Our findings suggest that the overall activity of the VASH pathway in leukocytes was reduced after tumor removal, highlighting the potential of leukocyte physiology as a novel biomarker for cancer surveillance and control.

Tregs are involved in VEGFA/ VASH1-related angiogenesis pathway in ovarian cancer

Vasohibin1 (VASH1) is a kind of vasopressor, produced by negative feedback from vascular endothelial growth factor A (VEGFA). Anti-angiogenic therapy targeting VEGFA is currently the first-line treatment for advanced ovarian cancer (OC), but there are still many adverse effects. Regulatory T cells (Tregs) are the main lymphocytes mediating immune escape function in the tumor microenvironment (TME) and have been reported to influence the function of VEGFA. However, whether Tregs are associated with VASH1 and angiogenesis in TME in OC is unclear. We aimed to explore the relationship between angiogenesis and immunosuppression in the TME of OC. We validated the relationship between VEGFA, VASH1, and angiogenesis in ovarian cancer and their prognostic implications. The infiltration level of Tregs and its marker forkhead box protein 3 (FOXP3) were explored in relation to angiogenesis-related molecules. The results showed that VEGFA and VASH1 were associated with clinicopathological stage, microvessel density and poor prognosis of ovarian cancer. Both VEGFA and VASH1 expression were associated with angiogenic pathways and there was a positive correlation between VEGFA and VASH1 expression. Tregs correlated with angiogenesis-related molecules and indicated that high FOXP3 expression is harmful to the prognosis. Gene set enrichment analysis (GSEA) predicted that angiogenesis, IL6/JAK/STAT3 signaling, PI3K/AKT/mTOR signaling, TGF-β signaling, and TNF-α signaling via NF-κB may be common pathways for VEGFA, VASH1, and Tregs to be involved in the development of OC. These findings suggest that Tregs may be involved in the regulation of tumor angiogenesis through VEGFA and VASH1, providing new ideas for synergistic anti-angiogenic therapy and immunotherapy in OC.

Clinicopathological Role of Vasohibin in Gastroenterological Cancers: A Meta-Analysis

Vasohibin-1 (VASH1) is an angiogenesis inhibitor, while vasohibin-2 (VASH2) is a proangiogenic factor. The roles of VASH1 and VASH2 expression in gastroenterological cancers remain unclear. We searched for relevant literature, specifically studies on gastroenterological cancer, and evaluated the relationship between VASH expression and clinical outcomes. Nine studies on VASH1 involving 1,574 patients were included. VASH1 expression was associated with the TNM stage [OR (odds ratio) 2.05, 95% CI (confidence interval) 1.24-3.40], lymph node metastasis (OR 1.79, 95% CI 1.24-2.58), lymphatic invasion (OR 1.95, 95% CI 1.41-2.68), and venous invasion (OR 2.49, 95% CI 1.60-3.88); poor clinical outcomes were associated with high VASH1 expression. High VASH1 expression was associated with a significantly shorter overall survival (OS) [HR (hazard ratio) 1.69, 95% CI 1.25-2.29] and disease-free survival (DFS) (HR 2.01, 95% CI 1.28-3.15). Three studies on VASH2 involving 469 patients were analyzed. VASH2 expression was associated with the TNM stage (OR 4.21, 95% CI 1.89-9.51) and venous invasion (OR 2.10, 95% CI 1.15-3.84); poor clinical outcomes were associated with high VASH2 expression. High VASH2 expression was associated with a significantly lower OS (HR 1.61, 95% CI 1.09-2.37). In conclusion, high VASH1 and VASH2 expression levels were associated with poor clinical outcomes and prognosis in patients with gastroenterological cancers.

High preoperative plasma vasohibin-1 concentration predicts better prognosis in patients with non-small cell lung carcinoma

BACKGROUND AND AIM

Vasohibin-1 (VASH1) is an angiogenesis inhibitor synthesized and secreted by endothelial cells, whose expression is induced by angiogenic stimuli such as vascular endothelial growth factor. We have previously demonstrated that VASH1 is immunohistochemically evident in endothelial cells in the tumor microenvironment of patients with non-small cell lung cancer (NSCLC) and is positively correlated with that of vascular endothelial growth factor in cancer cells. Here, we determined the preoperative plasma concentration of VASH1 in patients with NSCLC and evaluated the association between the preoperative VASH1 levels and certain outcomes.

METHODS

We analyzed presurgical plasma VASH1 concentrations in a total of 79 lung cancer patients (51 males and 28 females; 34-83 y of age; 46 adenocarcinomas, 27 squamous cell carcinomas, and 6 other types) who underwent lung resection. The impact of preoperative VASH1 level was analyzed using clinical characteristics and prognosis.

RESULTS

Plasma VASH1 concentration ranged from 34.1 to 1190.4 fmol/mL. We divided the patients into 3 groups according to plasma VASH1 level for this assessment: low VASH1 group (n = 26), medium VASH1 group (n = 27), and high VASH1 group (n = 26). The death and recurrence rates of the high, medium, and low VASH1 groups were 5.5, 16.2, and 12.7 per 100 person-years, respectively. Multivariate adjusted hazard ratio of death and recurrence of the high VASH1 group was lower than that of the low VASH1 group (hazard ratio 0.42; 95% CI 0.17-0.99).

CONCLUSION

The present analysis suggests that high preoperative plasma VASH1 concentration is associated with better prognosis in patients with NSCLC. We propose preoperative VASH1 level as a biomarker for the prognosis of patients with non-small cell lung carcinoma.

Association between TAp73, p53 and VASH1 expression in lung adenocarcinoma

TAp73 and p53 are involved in regulating tumor angiogenesis and vasohibin-1 (VASH1) is an anti-angiogenic factor. Whether TAp73 regulates angiogenesis positively or negatively is controversial. The status of P53 may determine the effect of TAp73 on angiogenesis. To the best of our knowledge it has not been previously reported whether TAp73, p53 and VASH1 are coexpressed in lung cancer. We profiled the association between TAp73 and p53 and VASH1 expression in lung adenocarcinoma (LAC) and investigated the function of TAp73 in regulating tumor angiogenesis. TAp73, p53 and VASH1 expression in 53 human LAC tissues and the adjacent normal tissues were evaluated using immunohistochemistry. The positive expression rates of p53, TAp73 and VASH1 were significantly higher (92.6, 97.7 and 67.4%, respectively) in LAC tissue compared with paraneoplastic lung tissue (7.4, 2.3 and 32.6%, respectively, P<0.01). Pearson's correlation coefficient showed a significant positive correlation between p53 and TAp73 (r=0.474, P<0.01) and TAp73α and VASH1 (r=0.367, P<0.01). The positive expression rate of p53 and VASH1 was almost significantly correlated (r=0.187, P=0.055). Similarly, p53 expression intensity had a significant positive correlation with TAp73α (r=0.517, P<0.01) and with VASH1 (r=0.277, P<0.01), as did TAp73α with VASH1 (r=0.351, P<0.01). TAp73, p53 (mutant) and VASH1 expression was significantly higher in LAC tissue compared with paraneoplastic lung tissue. The expression trends of the three proteins were significantly positively correlated with each other in LAC. These results suggest that TAp73 may suppress tumor angiogenesis in LAC.

Transcriptional landscape of human cancers

The homogeneity and heterogeneity in somatic mutations, copy number alterations and methylation across different cancer types have been extensively explored. However, the related exploration based on transcriptome data is lacking. In this study we explored gene expression profiles across 33 human cancer types using The Cancer Genome Atlas (TCGA) data. We identified consistently upregulated genes (such as E2F1, EZH2, FOXM1, MYBL2, PLK1, TTK, AURKA/B and BUB1) and consistently downregulated genes (such as SCARA5, MYOM1, NKAPL, PEG3, USP2, SLC5A7 and HMGCLL1) across various cancers. The dysregulation of these genes is likely to be associated with poor clinical outcomes in cancer. The dysregulated pathways commonly in cancers include cell cycle, DNA replication, repair, and recombination, Notch signaling, p53 signaling, Wnt signaling, TGFβ signaling, immune response etc. We also identified genes consistently upregulated or downregulated in highly-advanced cancers compared to lowly-advanced cancers. The highly (low) expressed genes in highly-advanced cancers are likely to have higher (lower) expression levels in cancers than in normal tissue, indicating that common gene expression perturbations drive cancer initiation and cancer progression. In addition, we identified a substantial number of genes exclusively dysregulated in a single cancer type or inconsistently dysregulated in different cancer types, demonstrating the intertumor heterogeneity. More importantly, we found a number of genes commonly dysregulated in various cancers such as PLP1, MYOM1, NKAPL and USP2 which were investigated in few cancer related studies, and thus represent our novel findings. Our study provides comprehensive portraits of transcriptional landscape of human cancers.

The roles of vasohibin and its family members: Beyond angiogenesis modulators

Vasohibin-1 is an intrinsic angiogenesis inhibitor, and is expressed in endothelial cells via induction by pro-angiogenesis factors. It is known to inhibit several processes of angiogenesis, with different mechanisms from extrinsic angiogenesis inhibitors. Vasohibin-2 is mainly expressed by mononuclear cells which have been mobilized from bone marrow. It not only promotes angiogenesis, but also modulates the releases of FGF-2 and VEGF, which are the two major inducers for vasohibin1. Hypoxic environment induces the expression of hypoxia-inducible Factor 1α with a result of VEGF release nearly in all tumor cell lines and tissues. However, it has been observed that hypoxia reduces the inducible effects of VEGF on vasohibin, which indicates that a complicated mechanism exists in the angiogenesis. Vasohibin and its family members play important roles in both the physiological and pathological procedures, in contrary but complementary patterns. Furthermore, human aortic smooth muscle cells and fibroblast have also been detected to express vasohibin on a moderate to weak scale range. Recently, the results of an increasing number of studies in vivo have shown that vasohibin can also be detected in several cancers, and is associated with micro-vessel densities, histology grades, invasions, poor clinical features, metastasis, and dissemination in abdominal cavities, as well as EMT. In more recent reports, it has been confirmed that, along with being angiogenesis regulators, a variety of other roles have been associated with this family. The focus of this study was the upstream regulatory mechanisms of vasohibin expressions, and their role in regard to the downstream target proteins of vasohibin, especially in carcinoma. Vasohibin is considered to be an original angiogenesis inhibitor, and has a much broader significance in pathological processes. It can be taken as an independent prognostic factor, as well as a potential strategy for cancer therapy programs.

Clinical implications of vasohibin-1 in esophageal carcinoma cells: Inhibition of cell growth and migration

As one of the first-established negative feedback regulators of angiogenesis, mesenchymal vasohibin-1 (VASH1) serves important roles in the progression and prognosis of various types of tumor. However, the clinical implications of VASH1 in esophageal carcinoma (EC) cells have not been reported and the direct effects of VASH1 on EC cells remain unknown. In the present study, the expression of VASH1 in EC cells was observed using immunohistochemistry and western blotting; a χ2 test was used to analyze the correlation of VASH1 with clinical parameters, and it was observed that VASH1 was negatively-correlated with tumor size (r=‑0.399; P<0.01) and invasion depth (r=‑0.318; P<0.01). Survival analysis demonstrated that VASH1 was positively‑correlated with increased overall survival (P=0.039) and disease free survival (P=0.012). The direct effects of VASH1 on EC cells were analyzed by altering VASH1 expression, and it was observed that downregulation of VASH1 increased proliferation, clone formation and the migratory ability of EC9706 cells, whereas upregulation of VASH1 inhibited proliferation, clone formation and the migratory ability of EC1 cells. The results of the present study demonstrated that VASH1 in EC cells was negatively‑correlated with progression and poor prognosis of patients with EC. VASH1 was able to directly inhibit the growth and migration of EC cells.

Keratin 19 as a key molecule in progression of human hepatocellular carcinomas through invasion and angiogenesis

BACKGROUND

Keratin (K) 19-positive hepatocellular carcinoma (HCC) is well known to have a higher malignant potential than K19-negative HCC: However, the molecular mechanisms involved in K19-mediated progression of HCC remain unclear. We attempted to clarify whether K19 directly affects cell survival and invasiveness in association with cellular senescence or epithelial-mesenchymal transition (EMT) in K19-positive HCC.

METHODS

K19 expression was analysed in 136 HCC surgical specimens. The relationship of K19 with clinicopathological factors and survival was analysed. Further, the effect of K19 on cell proliferation, invasion, and angiogenesis was examined by silencing K19 in the human HCC cell lines, HepG2, HuH-7, and PLC/PRF/5. Finally, we investigated HCC invasion, proliferation, and angiogenesis using K19-positive HCC specimens.

RESULTS

Analysis of HCC surgical specimens revealed that K19-positive HCC exhibited higher invasiveness, metastatic potential, and poorer prognosis. In vitro experiments using the human HCC cell lines revealed that K19 silencing suppressed cell growth by inducting apoptosis or upregulating p16 and p27, resulting in cellular senescence. In addition, transfection with K19 siRNA upregulated E-cadherin gene expression, significantly inhibited the invasive capacity of the cells, downregulated angiogenesis-related molecules such as vasohibin-1 (VASH1) and fibroblast growth factor 1 (FGFR1), and upregulated vasohibin-2 (VASH2). K19-positive HCC specimens exhibited a high MIB-1 labelling index, decreased E-cadherin expression, and high microvessel density around cancer foci.

CONCLUSION

K19 directly promotes cancer cell survival, invasion, and angiogenesis, resulting in HCC progression and poor clinical outcome. K19 may therefore be a novel drug target for the treatment of K19-positive HCC.

Vasohibin-1 suppresses colon cancer

Vasohibin-1 (VASH1) is an endogenous angiogenesis inhibitor.However, the clinical relevance of VASH1 in colon cancer and its regulations on cancer angiogenesis and cancer cell biological characteristics are still unknown. Here we showed that stromal VASH1 levels were negatively correlated with tumor size, advanced clinical stage and distant metastases in colon cancer patients. Overexpression of VASH1 in colon cancer cells induced apoptosis and senescence, inhibiting cancer cell growth and colony formation in vitro and tumor growth in vivo. In addition, knockdown of VASH1 in cancer cells promoted cell growth, adhesion and migration in vitro, and enhanced tumorigenesis and metastasis in vivo.

Proteolytic inactivation of anti-angiogenic vasohibin-1 by cancer cells

Vasohibin-1 (VASH1) is an angiogenesis inhibitor synthesized by endothelial cells (ECs) under conditions associated with physiological and pathological angiogenesis including cancers. VASH1, which is a 44-kDa protein, is processed after its translation and secretion, and a 29 kDa product cleaved both N-terminal and C-terminal end loses its anti-angiogenic activity. Here, we tested whether cancer cells modulate the processing of VASH1. When mouse EC line MS1 stably overexpressing the human VASH1 gene (MS1-hVASH1) and various cancer cell lines were co-cultured, there was an increased processing of hVASH1 protein in the culture media. This augmented processing was abrogated by a general cysteine protease inhibitor, E-64, and also by a specific calpain inhibitor, MDL28170. Recombinant hVASH1 protein was degraded by µ-calpain in vitro, which degradation was blocked by calpeptin. Conditioned media from co-cultures had little effect on the migration of human umbilical vein endothelial cells, but exhibited an inhibitory effect on their migration when collected in the presence of MDL28170; and this inhibitory effect was blocked by neutralizing anti-hVASH1 mAb. These results indicate that cancer cells proteolytically inactivate VASH1 protein secreted by ECs in the tumour microenvironment.

Mining distinct aldehyde dehydrogenase 1 (ALDH1) isoenzymes in gastric cancer

Aldehyde dehydrogenase 1 (ALDH1) consists of a family of intracellular enzymes, highly expressed in stem cells populations of leukemia and some solid tumors. Up to now, 6 isoforms of ALDH1 have been reported. However, the expression patterns and the identity of ALDH1 isoenzymes contributing to ALDH1 activity, as well as the prognostic values of ALDH1 isoenzymes in cancers all remain to be elucidated. Here, we studied the expressions of ALDH1 transcripts in gastric cancer (GC) compared with the normal controls using the ONCOMINE database. Through the Kaplan-Meier plotter database, which contains updated gene expression data and survival information of 876 GC patients, we also investigated the prognostic values of ALDH1 isoenzymes in GC patients. It was found that when compared with normal tissues, ALDH1A1 mRNA expression was downregulated, whereas ALDH1A3 and ALDH1B1 were upregulated in GC patients. In survival analyses, high ALDH1A1 and ALDH1B1 expressions were associated with better overall survival (OS) in all GC patients. In addition, high transcription activity of ALDH1A1 predicted better OS in gastric intestinal type adenocarcinoma, but not in diffuse gastric adenocarcinoma. GC patients with high mRNA level of ALDH1B1 showed better OS in gastric intestinal type, and worse OS in diffuse type. Oppositely, high transcription activities of ALDH1A2, ALDH1A3 and ALDH1L1 predicted worsen overall survival in GC patients, suggesting that these isoenzymes might be responsible mainly for the ALDH1 activities in GC. These data provides ALDH1A2, ALDH1A3 and ALDH1L1 as excellent potential targets for individualized treatment of GC patients.

Novel Link between Inhibition of Angiogenesis and Tolerance to Vascular Stress

The functional integrity of the vascular endothelium is an essential component required for the maintenance of vascular health, thus counteracting the onset of vascular diseases, including atherosclerosis and vascular complications of diabetes. In light of this important role, the vascular endothelium is expected to have a self-defense system. One candidate factor of such a system is vasohibin-1 (VASH1), a protein that is preferentially expressed in vascular endothelial cells (ECs). The unique features of VASH1 are its anti-angiogenic activity and ability to promote the stress tolerance and survival of ECs. This review summarizes current knowledge regarding VASH1 in terms of its roles in maintaining vascular integrity and protecting the vasculature against various forms of stress.

Exacerbation of diabetic renal alterations in mice lacking vasohibin-1

Vasohibin-1 (VASH1) is a unique endogenous inhibitor of angiogenesis that is induced in endothelial cells by pro-angiogenic factors. We previously reported renoprotective effect of adenoviral delivery of VASH1 in diabetic nephropathy model, and herein investigated the potential protective role of endogenous VASH1 by using VASH1-deficient mice. Streptozotocin-induced type 1 diabetic VASH1 heterozygous knockout mice (VASH1^+/−) or wild-type diabetic mice were sacrificed 16 weeks after inducing diabetes. In the diabetic VASH1^+/− mice, albuminuria were significantly exacerbated compared with the diabetic wild-type littermates, in association with the dysregulated distribution of glomerular slit diaphragm related proteins, nephrin and ZO-1, glomerular basement membrane thickning and reduction of slit diaphragm density. Glomerular monocyte/macrophage infiltration and glomerular nuclear translocation of phosphorylated NF-κB p65 were significantly exacerbated in the diabetic VASH1^+/− mice compared with the diabetic wild-type littermates, accompanied by the augmentation of VEGF-A, M1 macrophage-derived MCP-1 and phosphorylation of IκBα, and the decrease of angiopoietin-1/2 ratio and M2 macrophage-derived Arginase-1. The glomerular CD31⁺ endothelial area was also increased in the diabetic VASH1^+/− mice compared with the diabetic-wild type littermates. Furthermore, the renal and glomerular hypertrophy, glomerular accumulation of mesangial matrix and type IV collagen and activation of renal TGF-β₁/Smad3 signaling, a key mediator of renal fibrosis, were exacerbated in the diabetic VASH1^+/− mice compared with the diabetic wild-type littermates. In conditionally immortalized mouse podocytes cultured under high glucose condition, transfection of VASH1 small interfering RNA (siRNA) resulted in the reduction of nephrin, angiopoietin-1 and ZO-1, and the augmentation of VEGF-A compared with control siRNA. These results suggest that endogenous VASH1 may regulate the development of diabetic renal alterations, partly via direct effects on podocytes, and thus, a strategy to recover VASH1 might potentially lead to the development of a novel therapeutic approach for diabetic nephropathy.

Urinary and plasma levels of vasohibin-1 can predict renal functional deterioration in patients with renal disorders

Vasohibin-1 (VASH-1) is a negative feedback regulator of angiogenesis, and a small vasohibin-binding protein (SVBP) serves as its secretory chaperone and contributes to its antiangiogenic effects. In the present study, we aimed to define the clinical significance of VASH-1 and SVBP in patients with chronic kidney disease (CKD). We recruited 67 Japanese hospitalized patients with renal disorders with (n = 45) or without (n = 22) renal biopsy samples and 10 Japanese healthy controls. We evaluated the correlations between the plasma and urinary levels of VASH-1/VASH-1-SVBP complex/SVBP and the clinicopathological parameters. The plasma levels of VASH-1 were inversely correlated with age and systolic and diastolic blood pressure and positively correlated with crescent formation. Increased plasma and urinary levels of VASH-1 and VASH-1-SVBP complex were significantly correlated with worse renal outcomes. These results demonstrate an association between elevated urinary and plasma levels of VASH-1 and progressive decline of the renal function, thus suggesting a potential role for VASH-1 in predicting a worse renal prognosis in patients with renal disease, including CKD.

The prognostic significance of vasohibin 1-associated angiogenesis in patients with hepatocellular carcinoma

Vasohibin 1, an endothelium-derived negative feedback regulator of angiogenesis, is induced by fibroblast growth factor 2 (FGF-2) and vascular endothelial growth factor A (VEGF-A). In this study, we retrospectively evaluated immunoreactivity of FGF-2 and VEGF-A as well as microvessel density (MVD) determined by expression of vasohibin 1 and CD34 (MVD-CD34) and correlated the findings with clinical outcomes of 181 patients with hepatocellular carcinoma (HCC). Double immunostaining of an endothelial marker CD34 and vasohibin 1 with Ki-67 was also performed to assess angiogenic activity of endothelial cells in HCC. The ratio of Ki-67-positive endothelial cells in vasohibin 1-positive vessels (22%) was significantly higher than that of CD34-positive vessels (9%, P < .001), suggesting the correlation between vasohibin 1 and neovascularization in endothelial cells of HCC. MVD-CD34 decreased, but the ratio of MVD determined by expression of vasohibin 1 to MVD-CD34 (vasohibin 1/CD34) increased significantly according to histologic grade. Vasohibin 1 was significantly correlated with the status of FGF-2 (P = .007) but not with that of VEGF-A (P = .055). The 10-year overall survival and the 2-year disease-free survival rates of the low vasohibin 1/CD34 group (vasohibin 1/CD34 ≤0.459) were significantly higher than those of the high vasohibin 1/CD34 group (vasohibin 1/CD34 >0.459) (survival, 48% versus 38% and 52% versus 35%; P < .001 and P < .05, respectively). In addition, vasohibin 1/CD34 in HCC patients was an independent marker of poor prognosis, as determined by multivariate analysis (risk ratio, 1.973; 95% confidence interval, 1.049-3.711; P = .035). Vasohibin 1/CD34 could identify the proliferative vessels and could be a useful biomarker for predicting the clinical outcome of HCC patients.

Enhanced cancer metastasis in mice deficient in vasohibin-1 gene

Vasohibin-1 (VASH1) is isolated as an endogenous angiogenesis inhibitor produced by the vascular endothelium. We previously reported that tumor growth and tumor angiogenesis were augmented in VASH1 (−/−) mice. Here we examined whether VASH1 plays any role in cancer metastasis. When Lewis lung carcinoma (LLC) cells were inoculated in the footpad to observe spontaneous metastasis, a significant increase in lung metastasis together with inguinal lymph node metastasis was evident in the VASH1 (−/−) mice. Histological analyses revealed that vessels of the footpad tumor in VASH1 (−/−) mice were more immature, having fewer mural cells. However, when LLC cells were injected into a tail vein, the extent of lung metastasis was unchanged between wild-type mice and VASH1 (−/−) mice. When VASH1 in endothelial cells in culture was knocked-down by siRNA, we observed a decrease in the content of ZO-1, a component of tight junctions, which decrease resulted in increased transmigration of cancer cells across the endothelial cell monolayer. These results indicate that endogenous VASH1 tightens the endothelial barrier and makes tumor vessels resistant to cancer metastasis.

A systematic review of microvascular invasion in hepatocellular carcinoma: diagnostic and prognostic variability

Selected patients with hepatocellular carcinoma are candidates to receive potentially curative treatments, such as hepatic resection or liver transplantation, but nevertheless there is a high risk of tumor recurrence. Microvascular invasion is a histological feature of hepatocellular carcinoma related to aggressive biological behavior. We systematically reviewed 20 observational studies that addressed the prognostic impact of microvascular invasion, either after liver transplantation or resection. Outcomes were disease-free survival and overall survival. In liver transplantation, the presence of microvascular invasion shortened disease-free survival at 3 years (relative risk (RR)=3.41 [2.05-5.7]; five studies, n=651) and overall survival both at 3 years (RR=2.41 [1.72-3.37]; five studies, n=1,938) and 5 years (RR=2.29 [1.85-2.83]; six studies, n=2,003). After liver resection, microvascular invasion impacted disease-free survival at 3 and 5 years (RR=1.82 [1.61-2.07] and RR=1.51 [1.29-1.77]; four studies, n=1,501 for both comparisons). However inter/intraobserver variability in reporting and the lack of definition and grading of microvascular invasion has led to great heterogeneity in evaluating this histological feature in hepatocellular carcinoma. Thus, there is an urgent need to clarify this issue, because determining prognosis and response to therapy have become important in the current management of hepatocellular carcinoma. In this systematic review, we summarize the diagnostic and prognostic data concerning microvascular invasion in hepatocellular carcinoma and present a basis for consensus on its definition.

The vasohibin family: a novel family for angiogenesis regulation

Angiogenesis, a formation of neovessels, is regulated by the local balance between angiogenesis stimulators and inhibitors. A number of such endogenous regulators of angiogenesis have been found in the body. Recently, vasohibin-1 (VASH1) was isolated as a negative feedback regulator of angiogenesis produced by endothelial cells (ECs) and subsequently vasohibin-2 (VASH2) as a homologue of VASH1. It was then explored that VASH1 is expressed in ECs to terminate angiogenesis, whereas VASH2 is expressed in cells other than ECs to promote angiogenesis in the mouse model of angiogenesis. This review will focus on the vasohibin family members, which are novel regulators of angiogenesis.

Reduced expression of vasohibin-1 is associated with clinicopathological features in renal cell carcinoma

Vasohibin-1(VASH1) has recently been isolated as a novel negative feedback inhibitor of angiogenesis. Several studies have demonstrated that VASH1 plays important roles in tumor angiogenesis but the role of this angiogenic inhibitor in renal cell carcinoma (RCC) has not been elucidated until now. In this study, we investigated the expression pattern of VASH1 and the association with clinicopathological features in RCC. Expression of VASH1, hypoxia-inducible factor-1α (HIF-1α), and microvessel density (MVD, labeled by CD34) was assessed by immunohistochemistry in 46 RCC specimens and 20 adjacent nontumorous renal tissues (ANRTs). Correlation between vasohibin-1 and HIF-1α, MVD, and clinicopathological features was then investigated. In RCC, VASH1 was expressed mainly in the cytoplasm and membrane of tumor cells and partly in vascular endothelial cells. In ANRT, it was mainly expressed in the cytoplasm and membrane of renal tubular epithelial cells and partly in vascular endothelial cells and glomerular mesangial cells. The expression level of VASH1 in RCC tissue was significantly lower than that in ANRT and was significantly reduced with the increased degree of malignancy in RCC tissues. In addition, a significantly negative correlation was noted between VASH1 expression and HIF-1α expression and a significantly negative correlation was noted between VASH1 expression and MVD in RCC. Therefore, VASH1 expression is reduced and it associates with clinicopathological features in RCC. Based on our findings and the knowledge of other angiogenesis inhibitors, we postulate that VASH1 would potentially be a biomarker and a candidate for molecular targeted therapy for patients with RCC in the future.