Inhibition of human natural killer cell functional activity by human aspartyl β-hydroxylase

Mechanisms of METTL14-Mediated m6A Modification in Promoting Iron Overload-Induced Lipid Peroxidative Damage in Vascular Endothelial Cells to Aggravate Atherosclerosis

Atherosclerosis (AS) is a chronic multifactorial disease with damage to vascular endothelial cells (VECs). This study sought to delve into the mechanism of methyltransferase-like 14 (METTL14) in iron overload-induced lipid peroxidative damage in AS. AS mouse model and cell model were established. Levels of METTL14/circRNA coded by the Arhgap12 (circARHGAP12)/Aspartate β-hydroxylase (ASPH) were determined. AS plaque area/lipid deposition/lipid metabolism in AS mice and iron overload in VECs were evaluated. N6-methyladenosine (m6A) level and METTL14 enrichment and human antigen R (HuR) in circARHGAP12 or ASPH were measured. The mRNA stability of circARHGAP12 or ASPH was analyzed. We observed that METTL14 was upregulated in AS mice. METTL14 downregulation reduced plaque area/lipid deposition/iron overload/peroxidative damage in AS mice. In cell models, METTL14 downregulation could VEC injury/iron overload/lipid peroxidative damage. Mechanically, METTL14 increased the stability and expression of circARHGAP12 through m6A modification, further stabilized ASPH mRNA, and promoted ASPH transcription by binding to HuR. Overexpression of circARHGAP12 or inhibition of ASPH averted the protective role of METTL14 downregulation against iron overload-induced peroxidative damage in AS. In conclusion, METTL14-mediated m6A modification upregulated circARHGAP12 and ASPH to aggravate overload-induced lipid peroxidative damage and facilitate AS progression.

Aspartate β-Hydroxylase Serves as a Prognostic Biomarker for Neoadjuvant Chemotherapy in Gastric Cancer

Neoadjuvant chemotherapy (NACT) has been established as being an effective treatment for advanced gastric cancer (GC), while the predictive biomarker of NACT efficacy remains under investigation. Aspartate β-hydroxylase (ASPH) represents an attractive target which is a highly conserved transmembrane enzyme overexpressed in human GC, and participates in the malignant transformation by promoting tumor cell motility. Here, we evaluated the expression of ASPH by immunohistochemistry in 350 GC tissues (including samples for NACT) and found that ASPH expression was higher in patients undergoing NACT compared with patients without NACT pre-operation. The OS and PFS time of ASPH-intensely positive patients was significantly shorter than that of the negative patients in the NACT group, while the difference was not significant in patients without NACT. We showed that ASPH knockout enhanced the inhibitory effects of chemotherapeutic drugs on the cell proliferation, migration, and invasion in vitro and suppressed tumor progression in vivo. Co-immunoprecipitation revealed that ASPH might interact with LAPTM4B to perform chemotherapeutic drug resistance. Our results suggested that ASPH might serve as a candidate biomarker to predict prognosis and a novel therapeutic target for gastric cancer patients treated with neoadjuvant chemotherapy.

Labyrinthin: A distinct pan-adenocarcinoma diagnostic and immunotherapeutic tumor specific antigen

Structural analysis and detection of optimal cell surface localization of labyrinthin, a pan-adenocarcinoma target, was studied with respect to adenocarcinoma specificity vs. normal and non-adenocarcinoma cells. Patient-derived tissue microarray immunohistochemistry (IHC) was performed on 729 commercially prepared tissue blocks of lung, colon, breast, pancreas, prostate, and ovary cancers combined, plus a National Cancer Institute (NCI) tissue microarray derived from another 236 cases. The results confirmed that anti-labyrinthin mouse monoclonal MCA 44-3A6 antibody recognized adenocarcinomas, but not normal or non-adenocarcinoma cancer cells. The consensus of multiple topology analysis programs on labyrinthin (255 amino acids) estimate a type II cell membrane associated protein with an N-terminus signal peptide. However, because the labyrinthin sequence is enveloped within the 758 amino acids of the intracellular aspartyl/asparaginyl beta-hydroxylase (ASPH), a purported tumor associated antigen, standard IHC methods that permeabilize cells can expose common epitopes. To circumvent antibody cross-reactivity, cell surface labyrinthin was distinguished from intracellular ASPH by FACS analysis of permeabilized vs non-permeabilized cells. All permeabilized normal, adeno-and non-adenocarcinoma cells produced a strong MCA 44-3A6 binding signal, likely reflecting co-recognition of intracellular ASPH proteins along with internalized labyrinthin, but in non-permeabilized cells only adenocarcinoma cells were positive for labyrinthin. Confocal microscopy confirmed the FACS results. Labyrinthin as a functional cell-surface marker was suggested when: 1) WI-38 normal lung fibroblasts transfected with labyrinthin sense cDNA displayed a cancerous phenotype; 2) antisense transfection of A549 human lung adenocarcinoma cells appeared more normal; and 3) MCA44-3A6 suppressed A549 cell proliferation. Collectively, the data indicate that labyrinthin is a unique, promising adenocarcinoma tumor-specific antigen and therapeutic target. The study also raises a controversial issue on the extent, specificity, and usefulness of ASPH as an adenocarcinoma tumor-associated antigen.

Aspartate β-Hydroxylase (ASPH) Expression in Acute Myeloid Leukemia: A Potential Novel Therapeutic Target

Background

Aspartate β-hydroxylase (ASPH) is an embryonic transmembrane protein aberrantly upregulated in cancer cells, associated with malignant transformation and, in some reports, with poor clinical prognosis.

Objective

To report the expression patterns of ASPH in acute myeloid leukemia (AML).

Methods

Cell surface expression of ASPH was measured via 8-color multiparameter flow cytometry in 41 AML patient samples (31 bone marrow, 10 blood) using fluorescein isothiocyanate (FITC)-conjugated anti-ASPH antibody, SNS-622. A mean fluorescent intensity (MFI) of 10 was used as a cutoff for ASPH surface expression positivity. Data regarding patient and disease characteristics were collected.

Results

ASPH surface expression was found on AML blasts in 16 samples (39%). Higher ASPH expression was seen in myeloblasts of African American patients (p=0.02), but no correlation was found between ASPH expression and other patient or disease characteristics. No association was found between ASPH status and CR rate (p=0.53), EFS (p=0.87), or OS (p=0.17).

Conclusions

ASPH is expressed on blasts in approximately 40% of AML cases, and may serve as a new therapeutically targetable leukemia-associated antigen.

FDX1 can Impact the Prognosis and Mediate the Metabolism of Lung Adenocarcinoma

Background: Lung cancer has emerged as one of the most common cancers in recent years. The mitochondrial electron transport chain (ETC) is closely connected with metabolic pathways and inflammatory response. However, the influence of ETC-associated genes on the tumor immune response and the pathogenesis of lung cancer is not clear and needs further exploration.

Methods: The RNA-sequencing transcriptome and clinical characteristic data of LUAD were downloaded from the Cancer Genome Atlas (TCGA) database. The LASSO algorithm was used to build the risk signature, and the prediction model was evaluated by the survival analysis and receiver operating characteristic curve. We explored the function of FDX1 through flow cytometry, molecular biological methods, and liquid chromatography–tandem mass spectrometry/mass spectrometry (LC–MS/MS).

Results: 12 genes (FDX1, FDX2, LOXL2, ASPH, GLRX2, ALDH2, CYCS, AKR1A1, MAOB, RDH16, CYBB, and CYB5A) were selected to build the risk signature, and the risk score was calculated with the coefficients from the LASSO algorithm. The 1-year, 3-year, and 5-year area under the curve (AUC) of ROC curves of the dataset were 0.7, 0.674, and 0.692, respectively. Univariate Cox analysis and multivariate Cox regression analysis indicated that the risk signature is an independent risk factor for LUAD patients. Among these genes, we focused on the FDX1 gene, and we found that knockdown of FDX1 neither inhibited tumor cell growth nor did it induce apoptosis or abnormal cell cycle distribution. But FDX1 could promote the ATP production. Furthermore, our study showed that FDX1 was closely related to the glucose metabolism, fatty acid oxidation, and amino acid metabolism.

Conclusion: Collectively, this study provides new clues about carcinogenesis induced by ETC-associated genes in LUAD and paves the way for finding potential targets of LUAD.

Konjac Glucomannan from Amorphophallus konjac enhances immunocompetence of the cyclophosphamide-induced immunosuppressed mice

This present study was designed to evaluate the immunomodulatory activity of Konjac glucomannan (KGM) on immunosuppressed mice induced by cyclophosphamide (CTX) treatment. The mice immunodeficiency model was established by CTX. KGM was used to modulate the activities of immunosuppressive mice. It was proved that KGM could promote the proliferation of lymphocyte, thymus, and spleen indices, and alleviate the atrophy of immune organs and weight loss. Besides, in mice serum, the levels of cytokines including TNF-α, IgG, IL-2, and the contents of hemolysin were also increased after treatment with KGM. Furtherly, in nonspecific immunity, KGM could enhance natural killer (NK) cell lethality and pinocytic activity of mouse peritoneal macrophages. Therefore, all of these results revealed that KGM could improve the reduced immunity of CTX-induced mice via modulation innate immunity and adaptive immunity.

Aspartate β-hydroxylase as a target for cancer therapy

As metastasis is a major cause of death in cancer patients, new anti-metastatic strategies are needed to improve cancer therapy outcomes. Numerous pathways have been shown to contribute to migration and invasion of malignant tumors. Aspartate β-hydroxylase (ASPH) is a key player in the malignant transformation of solid tumors by enhancing cell proliferation, migration, and invasion. ASPH also promotes tumor growth by stimulation of angiogenesis and immunosuppression. These effects are mainly achieved via the activation of Notch and SRC signaling pathways. ASPH expression is upregulated by growth factors and hypoxia in different human tumors and its inactivation may have broad clinical impact. Therefore, small molecule inhibitors of ASPH enzymatic activity have been developed and their anti-metastatic effect confirmed in preclinical mouse models. ASPH can also be targeted by monoclonal antibodies and has also been used as a tumor-associated antigen to induce both cluster of differentiation (CD) 8+ and CD4+ T cells in mice. The PAN-301-1 vaccine against ASPH has already been tested in a phase 1 clinical trial in patients with prostate cancer. In summary, ASPH is a promising target for anti-tumor and anti-metastatic therapy based on inactivation of catalytic activity and/or immunotherapy.

Recent advances in research on aspartate β-hydroxylase (ASPH) in pancreatic cancer: A brief update

Pancreatic cancer (PC) is a highly aggressive tumor, often difficult to diagnose and treat. Aspartate β-hydroxylase (ASPH) is a type II transmembrane protein and the member of α-ketoglutarate-dependent dioxygenase family, found to be overexpressed in different cancer types, including PC. ASPH appears to be involved in the regulation of proliferation, invasion and metastasis of PC cells through multiple signaling pathways, suggesting its role as a tumor biomarker and therapeutic target. In this review, we briefly summarize the possible mechanisms of action of ASPH in PC and recent progress in the therapeutic approaches targeting ASPH.

Development of a novel anti-human aspartyl-(asparaginyl) β-hydroxylase monoclonal antibody with diagnostic and therapeutic potential

Human aspartyl-(asparaginyl)-β-hydroxylase (HAAH) has recently been the subject of several studies, as it was previously observed to be overexpressed in numerous types of carcinoma cells and tissues in patient tumor samples. HAAH has been implicated in tumor invasion and metastasis, indicating that it may be an important target and biomarker for tumor diagnosis and treatment. However, the immunological tools currently available for the study of this protein, including monoclonal antibodies, are limited, as is the present knowledge regarding the role of HAAH in tumor therapy and diagnosis. In the present study, a recombinant C-terminal domain of HAAH was expressed in Pichia pastoris and a novel monoclonal antibody (mAb) targeting HAAH (HAAH-C) was constructed. Immunofluorescence and antibody-dependent cellular cytotoxicity (ADCC) assays were used to demonstrate the specificity and ADCC activity of this antibody. The results demonstrated that this anti-C-terminal HAAH mAB, in combination with an existing anti-N terminal HAAH mAb, exhibited a high response to native HAAH from carcinoma cell culture supernatant, as measured with a double antibody sandwich enzyme-linked immunosorbent assay. This validated novel mAB-HAAH-C may prompt further studies into the underlying mechanisms of HAAH, and the exploration of its potential in tumor diagnosis and therapy.