Wnt7a interaction with Fzd5 and detection of signaling activation using a split eGFP

Background: Mammalian target of rapamycin (mTOR) has been evidenced as a multimodal therapy in the path-ophysiological process of acute ischemic stroke (AIS). However, the pathway that minocycline targets mTOR signaling is not fully defined in the AIS pathogenesis. This study is to aim at the effects of minocycline on the mTOR signaling in the AIS process and further discover the underlying mechanisms of minocycline involved in the following change of mTOR signaling-autophagy. Methods: Cerebral ischemia/reperfusion (CIR) rat animal models were established with the transient suture occlusion into middle cerebral artery. Minocycline (50mg/kg) was given by intragastric administration. The Morris water maze was used to test the cognitive function of animals. Immunohistochemistry and immunofluorescence were introduced for testing the lev-els of synaptophysin and PSD-95. Western blot was conducted for investigating the levels of mTOR, p-mTOR (Ser2448), p70S6, p-p70S6 (Thr389), eEF2k, p-eEF2k (Ser366), p-eIF4B (Ser406), LC3, p62, synaptophysin and PSD-95. Results: Minocycline prevents cognitive decline of the MCAO stroke rats. Minocycline limits the expression of p-mTOR (Ser2448) and the downstream targets of mTOR [p70S6, p-p70S6 (Thr389), eEF2k, p-eEF2k (Ser366) and p-eIF4B (Ser406)] (P<0.01), while minocycline has no influence on mTOR. LC3-II abundance and the LC3-II/I ratio were upregu-lated in the hippocampus of the MCAO stroke rats by the minocycline therapy (P<0.01). p62 was downregulated in the hippocampus from the MCAO stroke rats administrated with minocycline therapy(P<0.01). The levels of SYP and PSD-95 were up-regulated in the brain of the MCAO stroke rats administrated with minocycline therapy. Conclusion: Minocycline prevents cognitive deficits via inhibiting mTOR signaling and enhancing autophagy process, and promoting the expression of pre-and postsynaptic proteins (synaptophysin and PSD-95) in the brain of the MCAO stroke rats. The potential neuroprotective role of minocycline in the process of cerebral ischemia may be related to mitigating is-chemia-induced synapse injury via inhibiting activation of mTOR signaling.

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Role of Jagged1-mediated Notch Signaling Activation in the Differentiation and Stratification of the Human Limbal Epithelium

Cells ◽

10.3390/cells9091945 ◽

2020 ◽

Vol 9 (9) ◽

pp. 1945

Author(s):

Sheyla González ◽

Maximilian Halabi ◽

David Ju ◽

Matthew Tsai ◽

Sophie X. Deng

Keyword(s):

Notch Signaling ◽

Progenitor Cell ◽

Basal Layer ◽

Notch Signaling Pathway ◽

Basal Cells ◽

Proliferation Markers ◽

Limbal Epithelium ◽

Asymmetric Divisions ◽

Signaling Activation

The Notch signaling pathway plays a key role in proliferation and differentiation. We investigated the effect of Jagged 1 (Jag1)-mediated Notch signaling activation in the human limbal stem/progenitor cell (LSC) population and the stratification of the limbal epithelium in vitro. After Notch signaling activation, there was a reduction in the amount of the stem/progenitor cell population, epithelial stratification, and expression of proliferation markers. There was also an increase of the corneal epithelial differentiation. In the presence of Jag1, asymmetric divisions were decreased, and the expression pattern of the polarity protein Par3, normally present at the apical-lateral membrane of basal cells, was dispersed in the cells. We propose a mechanism in which Notch activation by Jag1 decreases p63 expression at the basal layer, which in turn reduces stratification by decreasing the number of asymmetric divisions and increases differentiation.

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Genome-wide CRISPR/Cas9 screening identifies CARHSP1 responsible for radiation resistance in glioblastoma

Cell Death and Disease ◽

10.1038/s41419-021-04000-3 ◽

2021 ◽

Vol 12 (8) ◽

Author(s):

Guo-dong Zhu ◽

Jing Yu ◽

Zheng-yu Sun ◽

Yan Chen ◽

Hong-mei Zheng ◽

...

Keyword(s):

Cold Shock ◽

Mrna Level ◽

Critical Role ◽

Inflammatory Signaling ◽

Heat Stable ◽

Genome Wide ◽

Attractive Therapeutic Target ◽

Heat Stable Protein ◽

Signaling Activation ◽

Shock Proteins

AbstractGlioblastomas (GBM) is the most common primary malignant brain tumor, and radiotherapy plays a critical role in its therapeutic management. Unfortunately, the development of radioresistance is universal. Here, we identified calcium-regulated heat-stable protein 1 (CARHSP1) as a critical driver for radioresistance utilizing genome-wide CRISPR activation screening. This is a protein with a cold-shock domain (CSD)-containing that is highly similar to cold-shock proteins. CARHSP1 mRNA level was upregulated in irradiation-resistant GBM cells and knockdown of CARHSP1 sensitized GBM cells to radiotherapy. The high expression of CARHSP1 upon radiation might mediate radioresistance by activating the inflammatory signaling pathway. More importantly, patients with high levels of CARHSP1 had poorer survival when treated with radiotherapy. Collectively, our findings suggested that targeting the CARHSP1/TNF-α inflammatory signaling activation induced by radiotherapy might directly affect radioresistance and present an attractive therapeutic target for GBM, particularly for patients with high levels of CARHSP1.

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SHH-N non-canonically sustains androgen receptor activity in androgen-independent prostate cancer cells

Scientific Reports ◽

10.1038/s41598-021-93971-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Diana Trnski ◽

Maja Sabol ◽

Sanja Tomić ◽

Ivan Štefanac ◽

Milanka Mrčela ◽

...

Keyword(s):

Prostate Cancer ◽

Androgen Receptor ◽

Cancer Cells ◽

Therapy Resistance ◽

Androgen Deprivation ◽

Prostate Cancer Cells ◽

Androgen Independence ◽

Androgen Receptor Activity ◽

Signaling Activation ◽

Androgen Independent

AbstractProstate cancer is the second most frequent cancer diagnosed in men worldwide. Localized disease can be successfully treated, but advanced cases are more problematic. After initial effectiveness of androgen deprivation therapy, resistance quickly occurs. Therefore, we aimed to investigate the role of Hedgehog-GLI (HH-GLI) signaling in sustaining androgen-independent growth of prostate cancer cells. We found various modes of HH-GLI signaling activation in prostate cancer cells depending on androgen availability. When androgen was not deprived, we found evidence of non-canonical SMO signaling through the SRC kinase. After short-term androgen deprivation canonical HH-GLI signaling was activated, but we found little evidence of canonical HH-GLI signaling activity in androgen-independent prostate cancer cells. We show that in androgen-independent cells the pathway ligand, SHH-N, non-canonically binds to the androgen receptor through its cholesterol modification. Inhibition of this interaction leads to androgen receptor signaling downregulation. This implies that SHH-N activates the androgen receptor and sustains androgen-independence. Targeting this interaction might prove to be a valuable strategy for advanced prostate cancer treatment. Also, other non-canonical aspects of this signaling pathway should be investigated in more detail and considered when developing potential therapies.

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Lymph node metastasis-derived gastric cancer cells educate bone marrow-derived mesenchymal stem cells via YAP signaling activation by exosomal Wnt5a

Oncogene ◽

10.1038/s41388-021-01722-8 ◽

2021 ◽

Vol 40 (12) ◽

pp. 2296-2308

Author(s):

Mei Wang ◽

Xinxin Zhao ◽

Rong Qiu ◽

Zheng Gong ◽

Feng Huang ◽

...

Keyword(s):

Gastric Cancer ◽

Stem Cells ◽

Bone Marrow ◽

Mesenchymal Stem Cells ◽

Lymph Node ◽

Lymph Node Metastasis ◽

Metastatic Gastric Cancer ◽

Gastric Cancer Cells ◽

Node Metastasis ◽

Signaling Activation

AbstractLymph node metastasis (LNM), a common metastatic gastric-cancer (GC) route, is closely related to poor prognosis in GC patients. Bone marrow-derived mesenchymal stem cells (BM-MSCs) preferentially engraft at metastatic lesions. Whether BM-MSCs are specifically reprogrammed by LNM-derived GC cells (LNM-GCs) and incorporated into metastatic LN microenvironment to prompt GC malignant progression remains unknown. Herein, we found that LNM-GCs specifically educated BM-MSCs via secretory exosomes. Exosomal Wnt5a was identified as key protein mediating LNM-GCs education of BM-MSCs, which was verified by analysis of serum exosomes collected from GC patients with LNM. Wnt5a-enriched exosomes induced YAP dephosphorylation in BM-MSCs, whereas Wnt5a-deficient exosomes exerted the opposite effect. Inhibition of YAP signaling by verteporfin blocked LNM-GC exosome- and serum exosome-mediated reprogramming in BM-MSCs. Analysis of MSC-like cells obtained from metastatic LN tissues of GC patients (GLN-MSCs) confirmed that BM-MSCs incorporated into metastatic LN microenvironment, and that YAP activation participated in maintaining their tumor-promoting phenotype and function. Collectively, our results show that LNM-GCs specifically educated BM-MSCs via exosomal Wnt5a-elicited activation of YAP signaling. This study provides new insights into the mechanisms of LNM in GC and BM-MSC reprogramming, and will provide potential therapeutic targets and detection indicators for GC patients with LNM.

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Equine Genital Squamous Cell Carcinoma Associated with EcPV2 Infection: RANKL Pathway Correlated to Inflammation and Wnt Signaling Activation

Biology ◽

10.3390/biology10030244 ◽

2021 ◽

Vol 10 (3) ◽

pp. 244

Author(s):

Samanta Mecocci ◽

Ilaria Porcellato ◽

Federico Armando ◽

Luca Mechelli ◽

Chiara Brachelente ◽

...

Keyword(s):

Gene Expression ◽

Wnt Signaling ◽

Squamous Cell ◽

Molecular Mechanisms ◽

Animal Health ◽

Wnt Signaling Pathway ◽

Nuclear Factor ◽

Nuclear Factor Kappa ◽

Signaling Activation ◽

Expression Evaluation

Equine genital squamous cell carcinomas (egSCCs) are among the most common equine tumors after sarcoids, severely impairing animal health and welfare. Equus caballus papillomavirus type 2 (EcPV2) infection is often related to these tumors. The aim of this study was to clarify the molecular mechanisms behind egSCCs associated with EcPV2 infection, investigating receptor activator of nuclear factor-kappa B ligand (RANKL) signaling in NF-kB pathway, together with the Wnt and IL17 signaling pathways. We analyzed the innate immune response through gene expression evaluation of key cytokines and transcription factors. Moreover, Ki67 index was assessed with immunohistochemistry. EcPV2-E6 DNA was checked, and viral presence was confirmed in 21 positive out to 23 cases (91%). Oncogene expression was confirmed in 14 cases (60.8%) for E6 and in 8 (34.7%) for E2. RANKL, nuclear factor kappa-light-chain-enhancer of activated B cells (NFKB)-p50, NFKBp65, interleukin (IL)-6, IL17, IL23p19, IL8, IL12p35, IL12p40, β-catenin (BCATN1), FOS like 1 (FOSL1), and lymphoid enhancer binding factor 1 (LEF1) showed a significant upregulation in tumor samples compared to healthy tissues. Our results describe an inflammatory environment characterized by the activation of RANKL/RANK and IL17 with the relative downstream pathways, and a positive modulation of inflammatory cytokines genes such as IL6 and IL8. Moreover, the increase of BCATN1, FOSL1, and LEF1 gene expression suggests an activation of both canonical and non-canonical Wnt signaling pathway that could be critical for carcinogenesis and tumor progression.

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CSIG-13. TRPM7 INDUCES TUMORIGENESIS AND STEMNESS THROUGH NOTCH ACTIVATION IN GLIOMA

Neuro-Oncology ◽

10.1093/neuonc/noaa215.125 ◽

2020 ◽

Vol 22 (Supplement_2) ◽

pp. ii30-ii30

Author(s):

Jingwei Wan ◽

Alyssa Guo ◽

Mingli Liu

Keyword(s):

Notch Signaling ◽

Glioma Cell ◽

Glioma Cells ◽

Inhibitory Effect ◽

Notch Signaling Pathway ◽

Normal Brain ◽

Diffuse Astrocytoma ◽

Notch1 Signaling ◽

Signaling Activation ◽

Proliferation And Invasion

Abstract Our group found that the inhibitory effect of TRPM7 on proliferation and invasion of human glioma cell is mediated by multiple mechanisms. TRPM7 regulates miR-28-5p expression, which suppresses cell proliferation and invasion in glioma cells by targeting Ras-related protein Rap1b. In particular, our group found that TRPM7 channels regulate glioma stem cell (GSC) growth/proliferation through STAT3 and Notch signaling. However, which Notch component(s) is crucial for its activity regulated by TRPM7, and its relationship with other GSC markers, such as CD133 and ALDH1, remain unclear. In the current project, we elucidate the mechanisms of TRMP7’s regulation of Notch signaling pathway that contribute to the development and progression of glioma and maintenance of self-renewal and tumorigenicity of GSC using multiple glioma cell lines (GC) with different molecular subtypes and GSCs derived from the GC lines. 1) We first analyzed TRPM7 expression using the Oncomine database (https://www.oncomine.org) and found that the TRPM7 mRNA expression is significantly increased in anaplastic astrocytoma, diffuse astrocytoma, and GBM patients compared to that in normal brain tissue controls. 2) TRPM7 is expressed in GBM, and its channel activity is correlated with Notch1 activation. Inhibition of TRPM7 downregulates Notch1 signaling, while upregulation of TRPM7 upregulates Notch1 signaling. 3) GSC markers, CD133 and ALDH1, are correlated with TRPM7 in GBM. 4) Targeting TRPM7 suppresses the growth and proliferation of glioma cells through G1/S arrests and apoptosis of glioma cells. 5) Targeting Notch1 suppresses the TRPM7-induced growth and proliferation of glioma cells, as well as the expression of GSC markers CD133 and ALDH1. In summary, TRPM7 is responsible for sustained Notch signaling activation, enhanced expression of GSC markers, and regulation of glioma stemness, which contribute to malignant glioma cell growth and invasion. Notch1 and ligand DII4 are key components that contribute GSC stemness.

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