Serum vascular adhesion protein-1 predicts all-cause mortality and cancer-related mortality in subjects with colorectal cancer

The role of vascular adhesion protein-1 in diabetes and diabetic complications

Vascular adhesion protein-1 (VAP-1) plays a dual role with its adhesive and enzymatic properties, facilitating leukocyte migration to sites of inflammation and catalyzing the breakdown of primary amines into harmful by-products, which are linked to diabetic complications. Present in various tissues, VAP-1 also circulates in a soluble form in the bloodstream. Diabetes is associated with several complications such as cardiovascular disease, retinopathy, nephropathy, and neuropathy, significantly contributing to disability and mortality. These complications arise from hyperglycemia-induced oxidative stress, inflammation, and the formation of advanced glycation end-products (AGEs). Earlier research, including our own from the 1990s and early 2000s, has underscored the critical role of VAP-1 in these pathological processes, prompting extensive investigation into its contribution to diabetic complications. In this review, we examine the involvement of VAP-1 in diabetes and its complications, alongside its link to other conditions related to diabetes, such as cancer and metabolic dysfunction-associated fatty liver disease. We also explore the utility of soluble VAP-1 as a biomarker for diabetes, its complications, and other related conditions. Since the inhibition of VAP-1 to treat diabetic complications is a novel and promising treatment option, further studies are needed to translate the beneficial effect of VAP-1 inhibitors observed in animal studies to clinical trials recruiting human subjects. Besides, future studies should focus on using serum sVAP-1 levels for risk assessment in diabetic patients, identifying those who need intensive glycemic control, and determining the patient population that would benefit most from VAP-1 inhibitor therapies.

Crosstalk of cell death pathways unveils an autophagy-related gene AOC3 as a critical prognostic marker in colorectal cancer

The intricate crosstalk of various cell death forms was recently implicated in cancers, laying a foundation for exploring the association between cell death and cancers. Recent evidence has demonstrated that biological networks outperform snapshot gene expression profiles at discovering promising biomarkers or heterogenous molecular subtypes across different cancer types. In order to investigate the behavioral patterns of cell death-related interaction perturbation in colorectal cancer (CRC), this study constructed the interaction-perturbation network with 11 cell death pathways and delineated four cell death network (CDN) derived heterogeneous subtypes (CDN1-4) with distinct molecular characteristics and clinical outcomes. Specifically, we identified a subtype (CDN4) endowed with high autophagy activity and the worst prognosis. Furthermore, AOC3 was identified as a potential autophagy-related biomarker, which demonstrated exceptional predictive performance for CDN4 and significant prognostic value. Overall, this study sheds light on the complex interplay of various cell death forms and reveals an autophagy-related gene AOC3 as a critical prognostic marker in CRC.

Serum vascular adhesion protein-1 is associated with twelve-year risk of incident cancer, cancer mortality, and all-cause mortality: a community-based cohort study

Background

Vascular adhesion protein-1 (VAP-1), a dual-function glycoprotein, has been reported to play a crucial role in inflammation and tumor progression. We conducted a community-based cohort study to investigate whether serum VAP-1 could be a potential biomarker for predicting incident cancers and mortality.

Method

From 2006 to 2018, we enrolled 889 cancer-free subjects at baseline. Serum VAP-1 levels were measured using a time-resolved immunofluorometric assay. Cancer and vital status of the participants were obtained by linking records with the computerized cancer registry and death certificates in Taiwan.

Results

During a median follow-up of 11.94 years, 69 subjects developed incident cancers and 66 subjects died, including 29 subjects who died from malignancy. Subjects in the highest tertile of serum VAP-1 had a significantly higher risk of cancer incidence (p=0.0006), cancer mortality (p=0.0001), and all-cause mortality (p=0.0002) than subjects in the other tertiles. The adjusted hazard ratios per one standard deviation increase in serum VAP-1 concentrations were 1.28 for cancer incidence (95% CI=1.01-1.62), 1.60 for cancer mortality (95% CI=1.14-2.23), and 1.38 for all-cause mortality (95% CI=1.09-1.75). The predictive performance of serum VAP-1 was better than that of gender, smoking, body mass index, hypertension, diabetes, and estimated glomerular filtration rate but lower than that of age for cancer incidence, cancer mortality, and all-cause mortality, as evidenced by higher increments in concordance statistics and area under the receiver operating characteristic curve.

Conclusion

Serum VAP-1 levels are associated with a 12-year risk of incident cancer, cancer mortality, and all-cause mortality in a general population.

Prognosis-related metabolic genes in the development of colorectal cancer progress and perspective

Colorectal cancer (CRC) is one of the most commonplace malignant tumors in the world. The occurrence and development of CRC are involved in numerous events. Metabolic reprogramming is one of the hallmarks of cancer and is convoluted and associated with carcinogenesis. Lots of metabolic genes are involved in the occurrence and progression of CRC. Study methods combining tumor genomics and metabolomics are more likely to explore this field in depth. In this mini-review, we make the latest progress and future prospects into the different molecular mechanisms of seven prognosis-related metabolic genes, we screened out in previous research, involved in the occurrence and development of CRC.

Increased Vascular Adhesion Protein 1 (VAP-1) Levels are Associated with Alternative M2 Macrophage Activation and Poor Prognosis for Human Gliomas

Glioma is characterized by a high heterogeneity in the brain tumor. Abundant tumor-associated macrophages (TAMs) exist as neoplastic tissues, implicating tumor plasticity and thus leading to therapeutic challenges. Vascular adhesion protein (VAP-1) potentially serves as a mediator for TAM immunity in tumor milieu. We previously demonstrated that VAP-1 could contribute to tumor malignancy, but its characteristics in TAM immunity of glioma progression are still unclear. This study explored the association of VAP-1 expression with TAM distribution as well as the resulting clinical significance and prognostic value in human gliomas. An in-depth analysis of AOC3 (VAP-1) gene expression was performed using 695 glioma samples derived from the cancer genome atlas (TCGA)-lower grade glioma and glioblastoma (GBMLGG) cohort. Bioinformatic analysis confirmed that VAP-1 expression is associated with poor prognosis of glioma patients (p = 0.0283). VAP-1 and TAM biomarkers (CD68, iNOS, and CD163) were evaluated by immunohistochemistry in 108 gliomas from Kaohsiung Medical University Hospital. VAP-1+ was expressed in 56 (51.85%) cases and this phenotype revealed a significant association with overall survival in Kaplan–Meier analysis (p < 0.0001). Immunohistochemical double staining showed that VAP-1 immunoreactivity was present around CD163+ M2 infiltration location, including aggressive lesions and neighboring neovasculature. We demonstrated that high VAP-1 expression levels positively correlated with CD163+ M2 activation and coexpression of these two proteins was associated with worse survival in gliomas (p < 0.0001). Multivariate analysis indicated that VAP-1 alone and co-expressed with CD163 were the significantly independent indicators (both p < 0.0001). Furthermore, VAP-1/CD163 coexpression exhibited excellent diagnostic accuracy in gliomas (AUC = 0.8008). In conclusion, VAP-1 and TAM CD163 M2 coexpression was found in glioma tissues belonging to a highly malignant subgroup that was associated with poor prognosis. These results implied VAP-1 abundance is closely linked to alternative M2 activation during glioma progression. From the aforementioned data, a reasonable inference is that VAP-1 combined with targeting M2 immunity might be an effective therapeutic target for human gliomas.

Vascular Adhesion Protein-1: A Cell Surface Amine Oxidase in Translation

Significance: Vascular adhesion protein-1 (VAP-1) is an ectoenzyme that oxidates primary amines in a reaction producing also hydrogen peroxide. VAP-1 on the blood vessel endothelium regulates leukocyte extravasation from the blood into tissues under physiological and pathological conditions. Recent Advances: Inhibition of VAP-1 by neutralizing antibodies and by several novel small-molecule enzyme inhibitors interferes with leukocyte trafficking and alleviates inflammation in many experimental models. Targeting of VAP-1 also shows beneficial effects in several other diseases, such as ischemia/reperfusion, fibrosis, and cancer. Moreover, soluble VAP-1 levels may serve as a new prognostic biomarker in selected diseases. Critical Issues: Understanding the contribution of the enzyme activity-independent and enzyme activity-dependent functions, which often appear to be mediated by the hydrogen peroxide production, in the VAP-1 biology will be crucial. Similarly, there is a pressing need to understand which of the VAP-1 functions are regulated through the modulation of leukocyte trafficking, and what is the role of VAP-1 synthesized in adipose and smooth muscle cells. Future Directions: The specificity and selectivity of new VAP-1 inhibitors, and their value in animal models under therapeutic settings need to be addressed. Results from several programs studying the therapeutic potential of VAP-1 inhibition, which now are in clinical trials, will reveal the relevance of this amine oxidase in humans.

Vascular adhesion protein-1 as indicator of breast cancer tumor aggressiveness and invasiveness

Recent studies suggest that vascular adhesion protein-1 (VAP-1), a 180-KDa homodimeric glycoprotein, may be associated with cancer-related events including tumor cell migration, motility, invasion, or metastasis. Therefore, this study applies VAP-1 immunohistochemical staining to demonstrate the invasiveness component of the breast cancer. The VAP-1 staining results were compared in 148 breast cancer cases to identify possible correlations with clinical status, including age, tumor size, tumor grade, TNM stage, lymphatic invasion, metastasis, recurrence, and survival rate. Immunohistochemical staining results showed VAP-1 negative or weak staining in normal ducts and ductal carcinoma in situ (DCIS), but these phenotypes were positively associated with a stiffened VAP-1 that presented at the invasive front of the lesion. Our data demonstrated that VAP-1 expression was positively associated with lymphatic invasion, distant metastasis, and patient survival in breast carcinoma. Notably, VAP-1 expression was found to be significantly correlated with the overall survival (p < 0.0001). Multivariate Cox analysis indicated that VAP-1 expression was a significant independent prognostic indicator of overall survival in breast carcinoma (p < 0.0001). In conclusion, this study suggests that VAP-1 is linked to progression of tumor invasion and metastasis in breast carcinoma. VAP-1 is shown to be a biomarker that can be predict invasive potential and clinical outcome in breast cancer.

Overexpression of vascular adhesion protein-1 is associated with poor prognosis of astrocytomas

Vascular adhesion protein-1 (VAP-1) is one of the endothelial adhesion molecules that is believed to play a role in tumor progression and metastasis, supporting cancer cell extravasation. Very few studies have been performed on analyzing the contribution of VAP-1 in brain tumor. Astrocytomas are the most common type of brain tumors, which are classified by World Health Organization (WHO) into four grades according to the degree of malignancy. This study was designed to investigate VAP-1 expression level in different astrocytoma grades and its correlation with clinicopathological features as well as prognosis of astrocytoma patients. Eighty-seven patients with different grades of astrocytoma (WHO Grade I-Grade IV) were enrolled in this study. The expression of VAP-1 was assayed by immunohistochemistry. The correlation between VAP-1 expression and clinicopathological features was evaluated by Chi-square test, and overall survival was analyzed by Kaplan-Meier method. Cox regression analysis was applied to analyze the independent influence of each parameter on overall survival. The expression level of VAP-1 was significantly higher in diffuse astrocytoma than those of pilocytic astrocytoma (p < 0.0001). In the subgroup analysis, upregulated VAP-1 expression was frequently found in older age patients (≥50 years). The VAP-1 expression was found to be significantly correlated with the overall survival (p = 0.0002). There was a statistical correlation between VAP-1(high) tumors in diffuse astrocytoma and VAP-1(low) tumors in pilocytic astrocytoma (p < 0.0001). Multivariate Cox analysis indicated VAP-1 was an independent predictive marker for poorer prognosis (p = 0.0036). Therefore, VAP-1 could be a promising prognostic biomarker in astrocytoma.

Evaluation of serum and tissue levels of VAP-1 in colorectal cancer

Background

The endothelial adhesion molecule, vascular adhesion protein-1 (VAP-1, AOC3) promotes lymphocyte recruitment to tumours, although the contribution that VAP-1 makes to lymphocyte recruitment in human colorectal cancer (CRC) is unknown. VAP-1 exists in circulating soluble form (sVAP-1). A previous study demonstrated elevated sVAP-1 levels in CRC patients. The aim of this study was to confirm this finding and study the differences in tissue VAP-1 expression between CRC and healthy tissues.

Methods

sVAP-1 levels were measured in the serum of 31 patients with CRC and 31 age- and sex-matched controls. Tissue VAP-1 levels were measured by immunohistochemistry, quantitative real-time PCR and Western blotting.

Results

The mean sVAP-1 level ± SD was significantly lower in the CRC group compared with the control group (399 ± 138 ng/ml versus 510 ± 142 ng/ml, P = 0.003). Tissue VAP-1 protein and mRNA levels were significantly lower in CRC compared with normal colon tissue. VAP-1 immunostaining was practically absent from CRC.

Conclusions

VAP-1 is downregulated in human CRC and although the molecular basis of this down regulation is not yet known, we suggest it may be part of a mechanism used by the tumour to prevent the recruitment of anti-tumour immune cells. Our data contradicts the findings of others with regard sVAP-1 levels in patients with CRC. Possible reasons for this are discussed.

Evaluation of Serum Vascular Adhesion Protein-1 as a Potential Biomarker in Thyroid Cancer

Vascular adhesion protein-1 (VAP-1) is a glycoprotein that mediates tissue-selective lymphocyte adhesion. The prognostic value of VAP-1 has been determined in gastric cancer. The aim of this study was to evaluate the changes and the predictive value of serum VAP-1 in patients with thyroid cancer. A total of 126 patients with thyroid nodules and 53 healthy controls participated in this study. The patients were further divided into subgroup 1 (69 cases with benign thyroid nodules) and subgroup 2 (57 cases with thyroid cancer). Serum VAP-1 was measured by time-resolved immunofluorometric assay. Diagnostic value of presurgical VAP-1 for thyroid cancer was conducted by receiver operating characteristic (ROC) curves. Serum levels of VAP-1 were significantly lower in thyroid cancer group than in healthy control and benign thyroid nodule groups. VAP-1 concentrations negatively correlated with serum thyroglobulin (Tg) levels in thyroid cancer patients (r = -0.81; p < 0.001). The optimum cut-off value of VAP-1 was 456.6 ng/mL with a 77.4% specificity and 66.7% sensitivity for thyroid cancer diagnosis. Serum VAP-1 decreased in thyroid cancer patients and VAP-1 could be a potential useful adjunct biomarker in the diagnosis of thyroid cancer.

Vascular adhesion protein-1: Role in human pathology and application as a biomarker

Vascular adhesion protein-1 (VAP-1) is a member of the copper-containing amine oxidase/semicarbazide-sensitive amine oxidase (AOC/SSAO) enzyme family. SSAO enzymes catalyze oxidative deamination of primary amines, which results in the production of the corresponding aldehyde, hydrogen peroxide and ammonium. VAP-1 is continuously expressed as a transmembrane glycoprotein in the vascular wall during development and facilitates the accumulation of inflammatory cells into the inflamed environment in concert with other leukocyte adhesion molecules. The soluble form of VAP-1 is released into the circulation mainly from vascular endothelial cells. Over- and under-expression of sVAP-1 result in alterations of the reported reaction product levels, which are involved in the pathogenesis of multiple human diseases. The combination of enzymatic and adhesion capacities as well as its strong association with inflammatory pathologies makes VAP-1 an interesting therapeutic target for drug discovery. In this article, we will review the general characteristics and biological functions of VAP-1, focusing on its important role as a prognostic biomarker in human pathologies. In addition, the potential therapeutic application of VAP-1 inhibitors will be discussed.

Ectoenzymes in leukocyte migration and their therapeutic potential

Inflammation causes or accompanies a huge variety of diseases. Migration of leukocytes from the blood into the tissues, in the tissues, and from the tissues to lymphatic vasculature is crucial in the formation and resolution of inflammatory infiltrates. In addition to classical adhesion and activation molecules, several other molecules are known to contribute to the leukocyte traffic. Several of them belong to ectoenzymes, which are cell surface molecules having catalytically active sites outside the cell. We will review here how several ectoenzymes present on leukocytes or endothelial cell surface function as adhesins and/or modulate the extravasation cascade through their enzymatic activities. Moreover, their therapeutic potential as immune modulators in different experimental inflammation models and in clinical trials will be discussed.