Balancing AhR-Dependent Pro-Oxidant and Nrf2-Responsive Anti-Oxidant Pathways in Age-Related Retinopathy: Is SERPINE1 Expression a Therapeutic Target in Disease Onset and Progression?

SERPINE1 and its co-expressed genes are associated with the progression of clear cell renal cell carcinoma

BACKGROUND

Clear cell renal cell carcinoma(ccRCC) is a frequently occurring malignant tumor of the urinary system. Despite extensive research, the regulatory mechanisms underlying the pathogenesis and progression of ccRCC remain largely unknown.

METHODS

We downloaded 5 ccRCC expression profiles from the Gene Expression Omnibus (GEO) database and obtained the list of differentially expressed genes (DEGs). Using String and Cytoscape tools, we determined the hub genes of ccRCC, and then analyzed their relationship with ccRCC patient survival. Ultimately, we identified SERPINE1 as a prognostic factor in ccRCC. Meanwhile, we confirmed the role of SERPINE1 in 786-O cells by cell transfection and in vitro experiments.

RESULTS

Our analysis yielded a total of 258 differentially expressed genes, comprising 105 down-regulated genes and 153 up-regulated genes. Survival analysis of SERPINE1 expression in The Cancer Genome Atlas (TCGA) confirmed its association with the increase of tumor grade, lymph node metastasis, and tumor stage, as well as with shorter survival. Furthermore, we found that SERPINE1 expression levels were associated with CD8 + T cells, CD4 + T cells, B cells, macrophages, neutrophils, and dendritic cells. Cell experiments showed that knockdown SERPINE1 expression could inhibit the proliferation, migration and invasion of ccRCC cells. Among the co-expressed genes with the highest correlation, ITGA5, SLC2A3, SLC2A14, SHC1, CEBPB, and ADA were overexpressed and associated with shorter overall survival (OS) in ccRCC.

CONCLUSIONS

In this study, we identified hub genes that are strongly related to ccRCC, and highlights the potential utility of overexpressed SERPINE1 and its co-expressed genes could be used as prognostic and diagnostic biomarkers in ccRCC.

Indole-3-carbinol regulates microglia homeostasis and protects the retina from degeneration

BACKGROUND

Retinal degenerative diseases significantly contribute to visual impairment and blindness. Microglia reactivity is a hallmark of neurodegenerative diseases including retinal cell death and immunomodulation emerges as a therapeutic option. Indole-3-carbinol (I3C) is a natural ligand of aryl hydrocarbon receptor (AhR), with potent immunomodulatory properties. Here, we hypothesized that I3C may inhibit microglia reactivity and exert neuroprotective effects in the light-damaged murine retina mimicking important immunological aspects of retinal degeneration.

METHODS

BV-2 microglia were treated in vitro with I3C followed by lipopolysaccharide (LPS) stimulation to analyze pro-inflammatory and anti-oxidant responses by quantitative real-time PCR (qRT-PCR) and Western blots. Nitric oxide (NO) secretion, caspase 3/7 levels, phagocytosis rates, migration, and morphology were analyzed in control and AhR knockdown cells. I3C or vehicle was systemically applied to light-treated BALB/cJ mice as an experimental model of retinal degeneration. Pro-inflammatory and anti-oxidant responses in the retina were examined by qRT-PCR, ELISA, and Western blots. Immunohistochemical staining of retinal flat mounts and cryosections were performed. The retinal thickness and structure were evaluated by in vivo imaging using spectral domain-optical coherence tomography (SD-OCT).

RESULTS

The in vitro data showed that I3C potently diminished LPS-induced pro-inflammatory gene expression of I-NOS, IL-1ß, NLRP3, IL-6, and CCL2 and induced anti-oxidants gene levels of NQO1, HMOX1, and CAT1 in BV-2 cells. I3C also reduced LPS-induced NO secretion, phagocytosis, and migration as important functional microglia parameters. siRNA-mediated knockdown of AhR partially prevented the previously observed gene regulatory events. The in vivo experiments revealed that I3C treatment diminished light-damage induced I-NOS, IL-1ß, NLRP3, IL-6, and CCL2 transcripts and also reduced CCL2, I-NOS, IL-1ß, p-NFkBp65 protein levels in mice. Moreover, I3C increased anti-oxidant NQO1 and HMOX1 protein levels in light-exposed retinas. Finally, I3C therapy prevented the accumulation of amoeboid microglia in the subretinal space and protected from retinal degeneration.

CONCLUSIONS

The AhR ligand I3C potently counter-acts microgliosis and light-induced retinal damage, highlighting a potential treatment concept for retinal degeneration.

Knockdown of SERPINE1 reverses resistance of triple‑negative breast cancer to paclitaxel via suppression of VEGFA

Breast cancer (BC) has a poor prognosis and a high number of visceral metastases. Serine protease inhibitor, clade E member 1 (SERPINE1) is a molecule involved in several human malignancies. However, it remains unknown if SERPINE1 plays a role in the development of taxane resistance in TNBC cells. In the present study, the role and mechanism of SERPINE1 in the development of paclitaxel (PTX) resistance in TNBC cells were investigated. A bioinformatics analysis of gene expression profiles in PTX‑resistant cells indicated that SERPINE1 was significantly associated with PTX resistance. Furthermore, the levels of SERPINE1 mRNA and protein were higher in PTX‑resistant cells with respect to those in PTX‑sensitive parent cells. Knockdown of SERPINE1 significantly inhibited cell survival and induced cell apoptosis in vitro. In addition, SERPINE1 silencing led to downregulation of the key angiogenetic vascular endothelial growth factor A (VEGFA). Furthermore, suppression of SERPINE1 markedly attenuated tumor growth in vivo. Collectively, these findings indicated that SERPINE1 significantly contributed to the proliferation and apoptosis of TNBC cells by regulating VEGFA expression. The present study demonstrated SERPINE1 as an oncogene in PTX drug resistance of breast cancer, and revealed that it may serve as a possible target for treating BC.

In-silico simulated prototype-patients using TPMS technology to study a potential adverse effect of sacubitril and valsartan

Unveiling the mechanism of action of a drug is key to understand the benefits and adverse reactions of a medication in an organism. However, in complex diseases such as heart diseases there is not a unique mechanism of action but a wide range of different responses depending on the patient. Exploring this collection of mechanisms is one of the clues for a future personalized medicine. The Therapeutic Performance Mapping System (TPMS) is a Systems Biology approach that generates multiple models of the mechanism of action of a drug. Each molecular mechanism generated could be associated to particular individuals, here defined as prototype-patients, hence the generation of models using TPMS technology may be used for detecting adverse effects to specific patients. TPMS operates by (1) modelling the responses in humans with an accurate description of a protein network and (2) applying a Multilayer Perceptron-like and sampling strategy to find all plausible solutions. In the present study, TPMS is applied to explore the diversity of mechanisms of action of the drug combination sacubitril/valsartan. We use TPMS to generate a wide range of models explaining the relationship between sacubitril/valsartan and heart failure (the indication), as well as evaluating their association with macular degeneration (a potential adverse effect). Among the models generated, we identify a set of mechanisms of action associated to a better response in terms of heart failure treatment, which could also be associated to macular degeneration development. Finally, a set of 30 potential biomarkers are proposed to identify mechanisms (or prototype-patients) more prone of suffering macular degeneration when presenting good heart failure response. All prototype-patients models generated are completely theoretical and therefore they do not necessarily involve clinical effects in real patients. Data and accession to software are available at http://sbi.upf.edu/data/tpms/

Effects of collagen peptides intake on skin ageing and platelet release in chronologically aged mice revealed by cytokine array analysis

Action mechanisms underlying various biological activities of collagen peptides (CPs) remained to be elucidated. Cytokines may play an important role in mediating these health benefits of CPs. This study aimed to systemically examine the cytokines in skin and blood regulated by CPs intake. Thirteen‐month‐old female Kunming mice were administered with CPs for 2 months (0 or 400 mg/kg bodyweight/day). The cytokines in skin and plasma were analysed using a 53‐cytokine array and corresponding ELISA kits. In skin, CPs intake significantly down‐regulated placenta growth factor (PIGF‐2), insulin‐like growth factor (IGF)‐binding protein (IGFBP) ‐2 and IGFBP‐3, and up‐regulated platelet factor 4 (PF4), serpin E1 and transforming growth factor (TGF)‐β₁. CPs treatment also increased the type I collagen mRNA and protein levels and improved the aged skin collagen fibres. In plasma, nine cytokines were significantly down‐regulated by CPs intake compared to the model group: fibroblast growth factor (FGF)‐2, heparin‐binding (HB) epidermal growth factor (EGF)‐like growth factor (HB‐EGF), hepatocyte growth factor (HGF), platelet‐derived growth factor (PDGF)‐AB/BB, vascular endothelial growth factor (VEGF), chemokine (C‐X‐C motif) ligand 1 (KC), matrix metalloproteinase (MMP)‐9, interleukin (IL)‐1α and IL‐10; 2 cytokines were significantly up‐regulated, including TGF‐β₁ and serpin F1. Furthermore, CPs intake significantly decreased the level of platelet release indicators in the plasma and washed platelets, including PF4, granule membrane protein (GMP)‐140, β‐thromboglobulin and serotonin. These results provide a mechanism underlying anti‐skin ageing by CPs intake and highlight potential application of CPs as a healthcare supplement to combat cancer and cardiovascular disease by inhibiting platelet release.

A novel AhR ligand, 2AI, protects the retina from environmental stress

Various retinal degenerative diseases including dry and neovascular age-related macular degeneration (AMD), retinitis pigmentosa, and diabetic retinopathy are associated with the degeneration of the retinal pigmented epithelial (RPE) layer of the retina. This consequently results in the death of rod and cone photoreceptors that they support, structurally and functionally leading to legal or complete blindness. Therefore, developing therapeutic strategies to preserve cellular homeostasis in the RPE would be a favorable asset in the clinic. The aryl hydrocarbon receptor (AhR) is a conserved, environmental ligand-dependent, per ARNT-sim (PAS) domain containing bHLH transcription factor that mediates adaptive response to stress via its downstream transcriptional targets. Using in silico, in vitro and in vivo assays, we identified 2,2′-aminophenyl indole (2AI) as a potent synthetic ligand of AhR that protects RPE cells in vitro from lipid peroxidation cytotoxicity mediated by 4-hydroxynonenal (4HNE) as well as the retina in vivo from light-damage. Additionally, metabolic characterization of this molecule by LC-MS suggests that 2AI alters the lipid metabolism of RPE cells, enhancing the intracellular levels of palmitoleic acid. Finally, we show that, as a downstream effector of 2AI-mediated AhR activation, palmitoleic acid protects RPE cells from 4HNE-mediated stress, and light mediated retinal degeneration in mice.