Plexin-B2 Mediates Physiologic and Pathologic Functions of Angiogenin.

Angiogenin (ANG) is a secreted ribonuclease (RNase) with cell-type- and context-specific roles in growth, survival, and regeneration. Although these functions require receptor-mediated endocytosis and appropriate subcellular localization, the identity of the cell surface receptor remains undefined. Here, we show that plexin-B2 (PLXNB2) is the functional receptor for ANG in endothelial, cancer, neuronal, and normal hematopoietic and leukemic stem and progenitor cells. Mechanistically, PLXNB2 mediates intracellular RNA processing that contribute to cell growth, survival, and regenerative capabilities of ANG. Antibodies generated against the ANG-binding site on PLXNB2 restricts ANG activity in vitro and in vivo, resulting in inhibition of established xenograft tumors, ANG-induced neurogenesis and neuroprotection, levels of pro-self-renewal transcripts in hematopoietic and patient-derived leukemic stem and progenitor cells, and reduced progression of leukemia in vivo. PLXNB2 is therefore required for the physiological and pathological functions of ANG and has significant therapeutic potential in solid and hematopoietic cancers and neurodegenerative diseases.

Angiogenin Promotes Hematopoietic Regeneration by Dichotomously Regulating Quiescence of Stem and Progenitor Cells.

Regulation of stem and progenitor cell populations is critical in the development, maintenance, and regeneration of tissues. Here, we define a novel mechanism by which a niche-secreted RNase, angiogenin (ANG), distinctively alters the functional characteristics of primitive hematopoietic stem/progenitor cells (HSPCs) compared with lineage-committed myeloid-restricted progenitor (MyePro) cells. Specifically, ANG reduces the proliferative capacity of HSPC while simultaneously increasing proliferation of MyePro cells. Mechanistically, ANG induces cell-type-specific RNA-processing events: tRNA-derived stress-induced small RNA (tiRNA) generation in HSPCs and rRNA induction in MyePro cells, leading to respective reduction and increase in protein synthesis. Recombinant ANG protein improves survival of irradiated animals and enhances hematopoietic regeneration of mouse and human HSPCs in transplantation. Thus, ANG plays a non-cell-autonomous role in regulation of hematopoiesis by simultaneously preserving HSPC stemness and promoting MyePro proliferation. These cell-type-specific functions of ANG suggest considerable therapeutic potential.

Myeloid cells protect intestinal epithelial barrier integrity through the angiogenin/plexin-B2 axis.

Communication between myeloid cells and epithelium plays critical role in maintaining intestinal epithelial barrier integrity. Myeloid cells interact with intestinal epithelial cells (IECs) by producing various mediators; however, the molecules mediating their crosstalk remain incompletely understood. Here, we report that deficiency of angiogenin (Ang) in mouse myeloid cells caused impairment of epithelial barrier integrity, leading to high susceptibility to DSS-induced colitis. Mechanistically, myeloid cell-derived angiogenin promoted IEC survival and proliferation through plexin-B2-mediated production of tRNA-derived stress-induced small RNA (tiRNA) and transcription of ribosomal RNA (rRNA), respectively. Moreover, treatment with recombinant angiogenin significantly attenuated the severity of experimental colitis. In human samples, the expression of angiogenin was significantly down-regulated in patients with inflammatory bowel disease (IBD). Collectively, we identified, for the first time to our knowledge, a novel mediator of myeloid cell-IEC crosstalk in maintaining epithelial barrier integrity, suggesting that angiogenin may serve as a new preventive agent and therapeutic target for IBD.

Angiogenin and plexin-B2 axis promotes glioblastoma progression by enhancing invasion, vascular association, proliferation and survival.

BACKGROUND: Angiogenin is a multifunctional secreted ribonuclease that is upregulated in human cancers and downregulated or mutationally inactivated in neurodegenerative diseases. A role for angiogenin in glioblastoma was inferred from the inverse correlation of angiogenin expression with patient survival but had not been experimentally investigated. METHODS: Angiogenin knockout mice were generated and the effect of angiogenin deficiency on glioblastoma progression was examined. Angiogenin and plexin-B2 genes were knocked down in glioblastoma cells and the changes in cell proliferation, invasion and vascular association were examined. Monoclonal antibodies of angiogenin and small molecules were used to assess the therapeutic activity of the angiogenin-plexin-B2 pathway in both genetic and xenograft animal models. RESULTS: Deletion of Ang1 gene prolonged survival of PDGF-induced glioblastoma in mice in the Ink4a/Arf-/-:Pten-/- background, accompanied by decreased invasion, vascular association and proliferation. Angiogenin upregulated MMP9 and CD24 leading to enhanced invasion and vascular association. Inhibition of angiogenin or plexin-B2, either by shRNA, monoclonal antibody or small molecule inhibitor, decreases sphere formation of patient-derived glioma stem cells, reduces glioblastoma proliferation and invasion and inhibits glioblastoma growth in both genetic and xenograft animal models. CONCLUSIONS: Angiogenin and its receptor, plexin-B2, are a pair of novel regulators that mediate invasion, vascular association and proliferation of glioblastoma cells. Inhibitors of the angiogenin-plexin-B2 axis have therapeutic potential against glioblastoma.

Angiogenin maintains gut microbe homeostasis by balancing α-Proteobacteria and Lachnospiraceae.

OBJECTIVE: Antimicrobial peptides (AMPs) play essential roles in maintaining gut health and are associated with IBD. This study is to elucidate the effect of angiogenin (ANG), an intestine-secreted AMP, on gut microbiota and its relevance with IBD. DESIGN: The effect of ANG on microbiota and its contribution to colitis were evaluated in different colitis models with co-housing and faecal microbiota transplantation. ANG-regulated bacteria were determined by 16S rDNA sequencing and their functions in colitis were analysed by bacterial colonisation. The species-specific antimicrobial activity of ANG and its underlying mechanism were further investigated with microbiological and biochemical methods. ANG level and the key bacteria were characterised in IBD faecal samples. RESULTS: ANG regulated microbiota composition and inhibited intestinal inflammation. Specifically, Ang1 deficiency in mice led to a decrease in the protective gut commensal strains of Lachnospiraceae but an increase in the colitogenic strains of α-Proteobacteria. Direct binding of ANG to α-Proteobacteria resulted in lethal disruption of bacterial membrane integrity, and consequently promoted the growth of Lachnospiraceae, which otherwise was antagonised by α-Proteobacteria. Oral administration of ANG1 reversed the dysbiosis and attenuated the severity of colitis in Ang1-deficient mice. The correlation among ANG, the identified bacteria and IBD status was established in patients. CONCLUSION: These findings demonstrate a novel role of ANG in shaping gut microbe composition and thus maintaining gut health, suggesting that the ANG-microbiota axis could be developed as a potential preventive and/or therapeutic approach for dysbiosis-related gut diseases.

Angiogenin regulates PKD activation and COX-2 expression induced by TNF-α and bradykinin in the colonic myofibroblast.

INTRODUCTION: The myofibroblast is a gastrointestinal stromal cell that is a target of tumor necrosis factor-alpha (TNF-α), a pro-inflammatory cytokine strongly implicated in colitis-associated cancer. Crosstalk between TNF-α and other pro-inflammatory mediators amplify inflammatory signaling but the mechanism is unknown. Angiogenin (ANG) is a 14-kDa angiogenesis protein that is regulated in patients with inflammatory bowel disease. However, the role of ANG on inflammatory mediator crosstalk in the myofibroblast is unknown. METHODS: The human colonic myofibroblast cell line 18Co, as well as primary mouse and human colonic myofibroblasts, were exposed to TNF-α (10 ng/ml) and bradykinin (BK, 100 nM). ANG was quantified by ELISA. The expression of cyclo-oxygenase-2 (COX-2) and phosphorylation of PKD was assessed by Western Blot. RESULTS: Primary mouse and human colonic myofibroblasts exposed to TNF-α/BK led to enhanced PKD phosphorylation and synergistic COX-2 expression. 18Co cells secrete high levels of ANG (24h, 265 ± 5 pg/ml). The monoclonal antibody 26-2F, which neutralizes ANG, inhibited TNF-α/BK-mediated PKD phosphorylation and synergistic COX-2 expression in primary human myofibroblasts. Likewise, in primary mouse myofibroblasts that do not express ANG (ANG-KO), TNF-α/BK failed to enhance PKD phosphorylation and COX-2 expression. CONCLUSIONS: TNF-α/BK enhance PKD phosphorylation and COX-2 expression in primary mouse and human colonic myofibroblasts. Angiogenin is produced by the myofibroblast, and inhibition of ANG signaling, either by its absence (ANG-KO) or by pharmacologic inhibition, blocks enhanced PKD phosphorylation and synergistic COX-2 expression induced by TNF-α/BK. ANG mediates crosstalk signaling between TNF-α/BK in the regulation of stroma-derived COX-2 and may be a novel therapeutic target for the management of colitis-associated cancer.

Sub-chronic 90-day toxicity of neamine in SD rats and its anti-liver cancer activity in vitro and in vivo.

Neamine, an inhibitor of angiogenin (ANG), is a new investigative anticancer drug currently in preclinical stage. Here we report the 90-day sub-chronic toxicity of neamine in SD rats and its anti-liver cancer activity in vitro and in vivo. Neamine has a No Observed Adverse Effect Level (NOAEL) of 12 and 16mg·kg-1·d-1 for female and male rats, respectively. No mortality was found. The adverse effects included increased organ coefficients of spleen and kidney, increased BUN in both female and male rats at high dose, increased CR and decreased organ coefficients of heart and liver in male rats at high dose. All of which, except the kidney coefficient and BUN in males, returned to normal levels after 28-day recovery. Histopathological examination revealed vacuolar degeneration of glomerulus, degeneration of renal tubules and cast in the kidneys, which were also recovered except in males of high-dosing group. These results indicate that kidney is the most susceptible organ for neamine toxicity. Tissue microarray analysis validated that ANG is up-regulated in hepatocellular carcinoma accompanied by increased nuclear translocation, suggesting that ANG is a possible target for drug development in liver cancer treatment. Neamine blocked nuclear translocation of ANG in HUVEC and HepG2 cells, and inhibited ANG-stimulated cell proliferation without affecting basal level cell proliferation. Neamine also inhibited progression of HepG2 xenografts in athymic mice accompanied by decreased angiogenesis and cancer cell proliferation. These results suggest that neamine is a specific ANG inhibitor with low toxicity and high anti-liver cancer efficacy.

Angiogenin Mediates Cell-Autonomous Translational Control under Endoplasmic Reticulum Stress and Attenuates Kidney Injury.

Endoplasmic reticulum (ER) stress is involved in the pathophysiology of kidney disease and aging, but the molecular bases underlying the biologic outcomes on the evolution of renal disease remain mostly unknown. Angiogenin (ANG) is a ribonuclease that promotes cellular adaptation under stress but its contribution to ER stress signaling remains elusive. In this study, we investigated the ANG-mediated contribution to the signaling and biologic outcomes of ER stress in kidney injury. ANG expression was significantly higher in samples from injured human kidneys than in samples from normal human kidneys, and in mouse and rat kidneys, ANG expression was specifically induced under ER stress. In human renal epithelial cells, ER stress induced ANG expression in a manner dependent on the activity of transcription factor XBP1, and ANG promoted cellular adaptation to ER stress through induction of stress granules and inhibition of translation. Moreover, the severity of renal lesions induced by ER stress was dramatically greater in ANG knockout mice (Ang(-/-)) mice than in wild-type mice. These results indicate that ANG is a critical mediator of tissue adaptation to kidney injury and reveal a physiologically relevant ER stress-mediated adaptive translational control mechanism.

Transcription of angiogenin and ribonuclease 4 is regulated by RNA polymerase III elements and a CCCTC binding factor (CTCF)-dependent intragenic chromatin loop.

Angiogenin (ANG) and ribonuclease 4 (RNASE4), two members of the secreted and vertebrate-specific ribonuclease superfamily, play important roles in cancers and neurodegenerative diseases. The ANG and RNASE4 genes share genetic regions with promoter activities, but the structure and regulation of these putative promotes are unknown. We have characterized the promoter regions, defined the transcription start site, and identified a mechanism of transcription regulation that involves both RNA polymerase III (Pol III) elements and CCCTC binding factor (CTCF) sites. We found that two Pol III elements within the promoter region influence ANG and RNASE4 expression in a position- and orientation-dependent manner. We also provide evidence for the presence of an intragenic chromatin loop between the two CTCF binding sites located in two introns flanking the ANG coding exon. We found that formation of this intragenic loop preferentially enhances ANG transcription. These results suggest a multilayer transcriptional regulation of ANG and RNASE4 gene locus. These data also add more direct evidence to the notion that Pol III elements are able to directly influence Pol II gene transcription. Furthermore, our data indicate that a CTCF-dependent chromatin loop is able to differentially regulate transcription of genes that share the same promoters.

Ribonuclease/angiogenin inhibitor 1 regulates stress-induced subcellular localization of angiogenin to control growth and survival.

Angiogenin (ANG) promotes cell growth and survival. Under growth conditions, ANG undergoes nuclear translocation and accumulates in the nucleolus where it stimulates rRNA transcription. When cells are stressed, ANG mediates the production of tRNA-derived stress-induced small RNA (tiRNA), which reprograms protein translation into a survival mechanism. The ribonucleolytic activity of ANG is essential for both processes but how this activity is regulated is unknown. We report here that ribonuclease/angiogenin inhibitor 1 (RNH1) controls both the localization and activity of ANG. Under growth conditions, ANG is located in the nucleus and is not associated with RNH1 so that the ribonucleolytic activity is retained to ensure rRNA transcription. Cytoplasmic ANG is associated with and inhibited by RNH1 so that random cleavage of cellular RNA is prevented. Under stress conditions, ANG is localized to the cytoplasm and is concentrated in stress granules where it is not associated with RNH1 and thus remains enzymatically active for tiRNA production. By contrast, nuclear ANG is associated with RNH1 in stressed cells to ensure that the enzymatic activity is inhibited and no unnecessary rRNA is produced to save anabolic energy. Knockdown of RNH1 abolished stress-induced relocalization of ANG and decreased cell growth and survival.

Angiogenin stimulates ribosomal RNA transcription by epigenetic activation of the ribosomal DNA promoter.

Angiogenin (ANG) undergoes nuclear translocation and promotes ribosomal RNA (rRNA) transcription thereby enhancing cell growth and proliferation. However, the mode of action of ANG in stimulating rRNA transcription is unclear. Here, we show that ANG enhances the formation of RNA polymerase I (Pol I) pre-initiation complex at the ribosomal DNA (rDNA) promoter. ANG binds at the upstream control element (UCE) of the promoter and enhances promoter occupancy of RNA Pol I as well as the selectivity factor SL1 components TAFI 48 and TAFI 110. We also show that ANG increases the number of actively transcribing rDNA by epigenetic activation through promoter methylation and histone modification. ANG binds to histone H3, inhibits H3K9 methylation, and activates H3K4 methylation as well as H4 acetylation at the rDNA promoter. These data suggest that one of the mechanisms by which ANG stimulates rRNA transcription is through an epigenetic activation of rDNA promoter.

CDK6 inhibits de novo lipogenesis in white adipose tissues but not in the liver.

Increased de novo lipogenesis (DNL) in white adipose tissue is associated with insulin sensitivity. Under both Normal-Chow-Diet and High-Fat-Diet, mice expressing a kinase inactive Cyclin-dependent kinase 6 (Cdk6) allele (K43M) display an increase in DNL in visceral white adipose tissues (VAT) as compared to wild type mice (WT), accompanied by markedly increased lipogenic transcriptional factor Carbohydrate-responsive element-binding proteins (CHREBP) and lipogenic enzymes in VAT but not in the liver. Treatment of WT mice under HFD with a CDK6 inhibitor recapitulates the phenotypes observed in K43M mice. Mechanistically, CDK6 phosphorylates AMP-activated protein kinase, leading to phosphorylation and inactivation of acetyl-CoA carboxylase, a key enzyme in DNL. CDK6 also phosphorylates CHREBP thus preventing its entry into the nucleus. Ablation of runt related transcription factor 1 in K43M mature adipocytes reverses most of the phenotypes observed in K43M mice. These results demonstrate a role of CDK6 in DNL and a strategy to alleviate metabolic syndromes.

Genome-wide identification and quantitative analysis of cleaved tRNA fragments induced by cellular stress.

Certain stress conditions can induce cleavage of tRNAs around the anticodon loop via the use of the ribonuclease angiogenin. The cellular factors that regulate tRNA cleavage are not well known. In this study we used normal and eIF2α phosphorylation-deficient mouse embryonic fibroblasts and applied a microarray-based methodology to identify and compare tRNA cleavage patterns in response to hypertonic stress, oxidative stress (arsenite), and treatment with recombinant angiogenin. In all three scenarios mouse embryonic fibroblasts deficient in eIF2α phosphorylation showed a higher accumulation of tRNA fragments including those derived from initiator-tRNA(Met). We have shown that tRNA cleavage is regulated by the availability of angiogenin, its substrate (tRNA), the levels of the angiogenin inhibitor RNH1, and the rates of protein synthesis. These conclusions are supported by the following findings: (i) exogenous treatment with angiogenin or knockdown of RNH1 increased tRNA cleavage; (ii) tRNA fragment accumulation was higher during oxidative stress than hypertonic stress, in agreement with a dramatic decrease of RNH1 levels during oxidative stress; and (iii) a positive correlation was observed between angiogenin-mediated tRNA cleavage and global protein synthesis rates. Identification of the stress-specific tRNA cleavage mechanisms and patterns will provide insights into the role of tRNA fragments in signaling pathways and stress-related disorders.

Ribonuclease 4 protects neuron degeneration by promoting angiogenesis, neurogenesis, and neuronal survival under stress.

Altered RNA processing is an underlying mechanism of amyotrophic lateral sclerosis (ALS). Missense mutations in a number of genes involved in RNA function and metabolisms are associated with ALS. Among these genes is angiogenin (ANG), the fifth member of the vertebrate-specific, secreted ribonuclease superfamily. ANG is an angiogenic ribonuclease, and both its angiogenic and ribonucleolytic activities are important for motor neuron health. Ribonuclease 4 (RNASE4), the fourth member of this superfamily, shares the same promoters with ANG and is co-expressed with ANG. However, the biological role of RNASE4 is unknown. To determine whether RNASE4 is involved in ALS pathogenesis, we sequenced the coding region of RNASE4 in ALS and control subjects and characterized the angiogenic, neurogenic, and neuroprotective activities of RNASE4 protein. We identified an allelic association of SNP rs3748338 with ALS and demonstrated that RNASE4 protein is able to induce angiogenesis in in vitro, ex vivo, and in vivo assays. RNASE4 also induces neural differentiation of P19 mouse embryonal carcinoma cells and mouse embryonic stem cells. Moreover, RNASE4 not only stimulates the formation of neurofilaments from mouse embryonic cortical neurons, but also protects hypothermia-induced degeneration. Importantly, systemic treatment with RNASE4 protein slowed weight loss and enhanced neuromuscular function of SOD1 (G93A) mice.

CDK6 kinase activity is required for thymocyte development.

Cyclin-dependent kinase-6 (CDK6) is required for early thymocyte development and tumorigenesis. To mechanistically dissect the role of CDK6 in thymocyte development, we generated and analyzed mutant knock-in mice and found that mice expressing a kinase-dead Cdk6 allele (Cdk6(K43M)) had a pronounced reduction in thymocytes and hematopoietic stem cells and progenitor cells (Lin⁻Sca-1⁺c-Kit⁺ [LSK]). In contrast, mice expressing the INK4-insensitive, hyperactive Cdk6(R31C) allele displayed excess proliferation in LSK and thymocytes. However, this is countered at least in part by increased apoptosis, which may limit progenitor and thymocyte expansion in the absence of other genetic events. Our mechanistic studies demonstrate that CDK6 kinase activity contributes to Notch signaling because inactive CDK6 kinase disrupts Notch-dependent survival, proliferation, and differentiation of LSK, with concomitant alteration of Notch target gene expression, such as massive up-regulation of CD25. Further, knockout of CD25 in Cdk6(K43M) mice rescued most defects observed in young mice. These results illustrate an important role for CDK6 kinase activity in thymocyte development that operates partially through modulating Notch target gene expression. This role of CDK6 as a downstream mediator of Notch identifies CDK6 kinase activity as a potential therapeutic target in human lymphoid malignancies.

CDK6 is essential for mesenchymal stem cell proliferation and adipocyte differentiation.

Background: Overweight or obesity poses a significant risk of many obesity-related metabolic diseases. Among all the potential new therapies, stem cell-based treatments hold great promise for treating many obesity-related metabolic diseases. However, the mechanisms regulating adipocyte stem cells/progenitors (precursors) are unknown. The aim of this study is to investigate if CDK6 is required for mesenchymal stem cell proliferation and adipocyte differentiation. Methods: Cyclin-dependent kinase 6 (Cdk6) mouse models together with stem cells derived from stromal vascular fraction (SVF) or mouse embryonic fibroblasts (MEFs) of Cdk6 mutant mice were used to determine if CDK6 is required for mesenchymal stem cell proliferation and adipocyte differentiation. Results: We found that mice with a kinase inactive CDK6 mutants (K43M) had fewer precursor residents in the SVF of adult white adipose tissue (WAT). Stem cells from the SVF or MEFs of K43M mice had defects in proliferation and differentiation into the functional fat cells. In contrast, mice with a constitutively active kinase CDK6 mutant (R31C) had the opposite traits. Ablation of RUNX1 in both mature and precursor K43M cells, reversed the phenotypes. Conclusion: These results represent a novel role of CDK6 in regulating precursor numbers, proliferation, and differentiation, suggesting a potential pharmacological intervention for using CDK6 inhibitors in the treatment of obesity-related metabolic diseases.

Emerging role of angiogenin in stress response and cell survival under adverse conditions.

Angiogenin (ANG), also known as ribonuclease (RNASE) 5, is a member of the vertebrate-specific, secreted RNASE superfamily. ANG was originally identified as a tumor angiogenic factor, but its biological activity has been extended from inducing angiogenesis to stimulating cell proliferation and more recently, to promoting cell survival. Under growth conditions, ANG is translocated to nucleus where it accumulates in nucleolus and stimulates ribosomal RNA (rRNA) transcription, thus facilitating cell growth and proliferation. Under stress conditions, ANG is accumulated in cytoplasmic compartments and modulates the production of tiRNA, a novel class of small RNA that is derived from tRNA and is induced by stress. tiRNA suppress global protein translation by inhibiting both cap-dependent and -independent translation including that mediated by weak IRESes. However, strong IRES-mediated translation, a mechanism often used by genes involved in pro-survival and anti-apoptosis, is not affected. Thus, ANG-mediated tiRNA reprogram protein translation, save anabolic energy, and promote cell survival. This recently uncovered function of ANG presents a novel mechanism of action in regulating cell growth and survival.

Angiogenin inhibits nuclear translocation of apoptosis inducing factor in a Bcl-2-dependent manner.

Loss-of-function mutations in angiogenin (ANG) gene were discovered in amyotrophic lateral sclerosis (ALS) patients and ANG has been shown to prevent neuronal death both in vitro and in vivo. The neuro-protective activity of ANG was brought about partially by inhibiting stress-induced apoptosis. ANG attenuates both the extrinsic and the intrinsic apoptotic signals by activating Nf-κb-mediated cell survival pathway and Bcl-2-mediated anti-apoptotic pathway. Here we report that ANG inhibits nuclear translocation of apoptosis inducing factor (AIF), an important cell death-executing molecule known to play a dominant role in neurodegenerative diseases. ANG inhibits serum withdrawal-induced apoptosis by attenuating a series of Bcl-2-dependent events including caspase-3 activation, poly ADP-ribose polymerase-1 (PARP-1) cleavage, and AIF nuclear translocation.

Angiogenin variants in Parkinson disease and amyotrophic lateral sclerosis.

OBJECTIVE: Several studies have suggested an increased frequency of variants in the gene encoding angiogenin (ANG) in patients with amyotrophic lateral sclerosis (ALS). Interestingly, a few ALS patients carrying ANG variants also showed signs of Parkinson disease (PD). Furthermore, relatives of ALS patients have an increased risk to develop PD, and the prevalence of concomitant motor neuron disease in PD is higher than expected based on chance occurrence. We therefore investigated whether ANG variants could predispose to both ALS and PD. METHODS: We reviewed all previous studies on ANG in ALS and performed sequence experiments on additional samples, which allowed us to analyze data from 6,471 ALS patients and 7,668 controls from 15 centers (13 from Europe and 2 from the USA). We sequenced DNA samples from 3,146 PD patients from 6 centers (5 from Europe and 1 from the USA). Statistical analysis was performed using the variable threshold test, and the Mantel-Haenszel procedure was used to estimate odds ratios. RESULTS: Analysis of sequence data from 17,258 individuals demonstrated a significantly higher frequency of ANG variants in both ALS and PD patients compared to control subjects (p = 9.3 × 10(-6) for ALS and p = 4.3 × 10(-5) for PD). The odds ratio for any ANG variant in patients versus controls was 9.2 for ALS and 6.7 for PD. INTERPRETATION: The data from this multicenter study demonstrate that there is a strong association between PD, ALS, and ANG variants. ANG is a genetic link between ALS and PD.

Ribonuclease 4 is associated with aggressiveness and progression of prostate cancer.

Prostate specific antigen screening has resulted in a decrease in prostate cancer-related deaths. However, it also has led to over-treatment affecting the quality of life of many patients. New biomarkers are needed to distinguish prostate cancer from benign prostate hyperplasia (BPH) and to predict aggressiveness of the disease. Here, we report that ribonuclease 4 (RNASE4) serves as such a biomarker as well as a therapeutic target. RNASE4 protein level in the plasma is elevated in prostate cancer patients and is positively correlated with disease stage, grade, and Gleason score. Plasma RNASE4 level can be used to predict biopsy outcome and to enhance diagnosis accuracy. RNASE4 protein in prostate cancer tissues is enhanced and can differentiate prostate cancer and BPH. RNASE4 stimulates prostate cancer cell proliferation, induces tumor angiogenesis, and activates receptor tyrosine kinase AXL as well as AKT and S6K. An RNASE4-specific monoclonal antibody inhibits the growth of xenograft human prostate cancer cell tumors in athymic mice.