Ciliary Hedgehog signaling regulates cell survival to build the facial midline

Craniofacial defects are among the most common phenotypes caused by ciliopathies, yet the developmental and molecular etiology of these defects is poorly understood. We investigated multiple mouse models of human ciliopathies (including Tctn2, Cc2d2a and Tmem231 mutants) and discovered that each displays hypotelorism, a narrowing of the midface. As early in development as the end of gastrulation, Tctn2 mutants displayed reduced activation of the Hedgehog (HH) pathway in the prechordal plate, the head organizer. This prechordal plate defect preceded a reduction of HH pathway activation and Shh expression in the adjacent neurectoderm. Concomitant with the reduction of HH pathway activity, Tctn2 mutants exhibited increased cell death in the neurectoderm and facial ectoderm, culminating in a collapse of the facial midline. Enhancing HH signaling by decreasing the gene dosage of a negative regulator of the pathway, Ptch1, decreased cell death and rescued the midface defect in both Tctn2 and Cc2d2a mutants. These results reveal that ciliary HH signaling mediates communication between the prechordal plate and the neurectoderm to provide cellular survival cues essential for development of the facial midline.

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Ciliary Hedgehog signaling regulates cell survival to build the facial midline

10.1101/2021.03.18.436057 ◽

2021 ◽

Author(s):

Shaun R Abrams ◽

Jeremy F Reiter

Keyword(s):

Cell Death ◽

Hedgehog Signaling ◽

Gene Dosage ◽

Negative Regulator ◽

Cellular Survival ◽

Pathway Activation ◽

Prechordal Plate ◽

Facial Midline ◽

Hh Signaling ◽

Craniofacial Defects

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Repurposing Niclosamide for Targeting Pancreatic Cancer by Inhibiting Hh/Gli Non-Canonical Axis of Gsk3β

Cancers ◽

10.3390/cancers13133105 ◽

2021 ◽

Vol 13 (13) ◽

pp. 3105

Author(s):

Jyoti B. Kaushal ◽

Rakesh Bhatia ◽

Ranjana K. Kanchan ◽

Pratima Raut ◽

Surya Mallapragada ◽

...

Keyword(s):

Pancreatic Cancer ◽

Cell Death ◽

Therapeutic Efficacy ◽

Hedgehog Signaling ◽

Negative Regulator ◽

Phase Cell ◽

Cycle Arrest ◽

Hh Signaling ◽

And Migration

Niclosamide (Nic), an FDA-approved anthelmintic drug, is reported to have anti-cancer efficacy and is being assessed in clinical trials for various solid tumors. Based on its ability to target multiple signaling pathways, in the present study, we evaluated the therapeutic efficacy of Nic on pancreatic cancer (PC) in vitro. We observed an anti-cancerous effect of this drug as shown by the G0/G1 phase cell cycle arrest, inhibition of PC cell viability, colony formation, and migration. Our results revealed the involvement of mitochondrial stress and mTORC1-dependent autophagy as the predominant players of Nic-induced PC cell death. Significant reduction of Nic-induced reactive oxygen species (ROS) and cell death in the presence of a selective autophagy inhibitor spautin-1 demonstrated autophagy as a major contributor to Nic-mediated cell death. Mechanistically, Nic inhibited the interaction between BCL2 and Beclin-1 that supported the crosstalk of autophagy and apoptosis. Further, Nic treatment resulted in Gsk3β inactivation by phosphorylating its Ser-9 residue leading to upregulation of Sufu and Gli3, thereby negatively impacting hedgehog signaling and cell survival. Nic induced autophagic cell death, and p-Gsk3b mediated Sufu/Gli3 cascade was further confirmed by Gsk3β activator, LY-294002, by rescuing inactivation of Hh signaling upon Nic treatment. These results suggested the involvement of a non-canonical mechanism of Hh signaling, where p-Gsk3β acts as a negative regulator of Hh/Gli1 cascade and a positive regulator of autophagy-mediated cell death. Overall, this study established the therapeutic efficacy of Nic for PC by targeting p-Gsk3β mediated non-canonical Hh signaling and promoting mTORC1-dependent autophagy and cell death.

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Detection of Canonical Hedgehog Signaling in Breast Cancer by 131-Iodine-Labeled Derivatives of the Sonic Hedgehog Protein

Journal of Biomedicine and Biotechnology ◽

10.1155/2012/639562 ◽

2012 ◽

Vol 2012 ◽

pp. 1-8 ◽

Cited By ~ 8

Author(s):

Jennifer Sims-Mourtada ◽

David Yang ◽

Izabela Tworowska ◽

Richard Larson ◽

Daniel Smith ◽

...

Keyword(s):

Receptor Binding ◽

Hedgehog Signaling ◽

Receptor Expression ◽

Biodistribution Studies ◽

Pathway Activation ◽

Signaling Inhibitors ◽

Gastrointestinal Tissue ◽

Hh Signaling ◽

Significant Uptake

Activation of hedgehog (HH) pathway signaling is observed in many tumors. Due to a feedback loop, the HH receptor Patched (PTCH-1) is overexpressed in tumors with activated HH signaling. Therefore, we sought to radiolabel the PTCH-1 ligand sonic (SHH) for detection of cancer cells with canonical HH activity. Receptor binding of131I-SHH was increased in cell lines with high HH pathway activation. Our findings also show that PTCH-1 receptor expression is decreased upon treatment with HH signaling inhibitors, and receptor binding of131I-SHH is significantly decreased following treatment with cyclopamine.In vivoimaging and biodistribution studies revealed significant accumulation of131I-SHH within tumor tissue as compared to normal organs. Tumor-to-muscle ratios were approximately 8 : 1 at 5 hours, while tumor to blood and tumor to bone were 2 : 1 and 5 : 1, respectively. Significant uptake was also observed in liver and gastrointestinal tissue. These studies show that131I-SHH is capable ofin vivodetection of breast tumors with high HH signaling. We further demonstrate that the hedgehog receptor PTCH-1 is downregulated upon treatment with hedgehog inhibitors. Our data suggests that radiolabeled SHH derivatives may provide a method to determine response to SHH-targeted therapies.

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Xpo7 negatively regulates Hedgehog signaling by exporting Gli2 from the nucleus

10.1101/2020.01.31.928408 ◽

2020 ◽

Author(s):

Łukasz Markiewicz ◽

Tomasz Uśpieński ◽

Sylwia M. Niedziółka ◽

Paweł Niewiadomski

Keyword(s):

Nuclear Export ◽

Hedgehog Signaling ◽

Negative Regulator ◽

Nuclear Accumulation ◽

Gli Proteins ◽

Protein Activator ◽

Bidirectional Transport ◽

Hh Signaling ◽

Nuclear Shuttling ◽

Nuclear Export Receptor

AbstractDynamic bidirectional transport between the nucleus and the cytoplasm is critical for the regulation of many transcription factors, whose levels inside the nucleus must be tightly controlled. Efficient shuttling across the nuclear membrane is especially crucial with regard to the Hedgehog (Hh) pathway, where the transcriptional signal depends on the fine balance between the amounts of Gli protein activator and repressor forms in the nucleus. The nuclear export machinery prevents the unchecked nuclear accumulation of Gli proteins, but the mechanistic insight into this process is limited. We show that the atypical exportin Xpo7 functions as a major nuclear export receptor that actively excludes Gli2 from the nucleus and controls the outcome of Hh signaling. We show that Xpo7 interacts with several domains of Gli2 and that this interaction is dependent on SuFu, a key negative regulator of Hh signaling. Our data pave the way for a more complete understanding of the nuclear shuttling of Gli proteins and the regulation of their transcriptional activity.

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KIF14 controls ciliogenesis via regulation of Aurora A and is important for Hedgehog signaling

The Journal of Cell Biology ◽

10.1083/jcb.201904107 ◽

2020 ◽

Vol 219 (6) ◽

Cited By ~ 6

Author(s):

Petra Pejskova ◽

Madeline Louise Reilly ◽

Lucia Bino ◽

Ondrej Bernatik ◽

Linda Dolanska ◽

...

Keyword(s):

Cell Cycle ◽

Primary Cilium ◽

Hedgehog Signaling ◽

Cell Cycle Progression ◽

Primary Cilia ◽

Aurora A ◽

Pathway Activation ◽

Cilia Formation ◽

Tightly Coupled ◽

Hh Signaling

Primary cilia play critical roles in development and disease. Their assembly and disassembly are tightly coupled to cell cycle progression. Here, we present data identifying KIF14 as a regulator of cilia formation and Hedgehog (HH) signaling. We show that RNAi depletion of KIF14 specifically leads to defects in ciliogenesis and basal body (BB) biogenesis, as its absence hampers the efficiency of primary cilium formation and the dynamics of primary cilium elongation, and disrupts the localization of the distal appendage proteins SCLT1 and FBF1 and components of the IFT-B complex. We identify deregulated Aurora A activity as a mechanism contributing to the primary cilium and BB formation defects seen after KIF14 depletion. In addition, we show that primary cilia in KIF14-depleted cells are defective in response to HH pathway activation, independently of the effects of Aurora A. In sum, our data point to KIF14 as a critical node connecting cell cycle machinery, effective ciliogenesis, and HH signaling.

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The Hedgehog Co-Receptor BOC Differentially Regulates SHH Signaling During Craniofacial Development

10.1101/2020.02.04.934497 ◽

2020 ◽

Author(s):

Martha L. Echevarría-Andino ◽

Benjamin L. Allen

Keyword(s):

Neural Crest ◽

Hedgehog Signaling ◽

Developmental Time ◽

Craniofacial Development ◽

Pathway Activity ◽

Tissue Specific ◽

Summary Statement ◽

Hh Signaling ◽

The Individual ◽

Craniofacial Defects

AbstractThe Hedgehog (HH) pathway controls multiple aspects of craniofacial development. HH ligands signal through the canonical receptor PTCH1, and three co-receptors– GAS1, CDON and BOC. Together, these co-receptors are required during embryogenesis to mediate proper HH signaling. Here we investigated the individual and combined contributions of GAS1, CDON and BOC to HH-dependent mammalian craniofacial development. Individual deletion of either Gas1 or Cdon results in variable holoprosencephaly phenotypes, characterized by the failure to divide and form the telencephalon and midfacial structures. In contrast, we find that Boc deletion results in facial widening consistent with increased HH pathway activity. Additionally, the deletion of Boc in a Gas1 null background partially rescues the craniofacial defects observed in Gas1 single mutants; a phenotype that persists over developmental time. This contrasts with HH-dependent phenotypes in other tissues that significantly worsen following combined deletion of Gas1 and Boc. Mechanistically, BOC selectively restricts neural crest-derived mesenchymal proliferation. Together, these data indicate that BOC acts as a multi-functional regulator of HH signaling during craniofacial development, alternately promoting or restraining HH pathway activity in a tissue-specific fashion.Summary statementHere we identify dual, tissue-specific roles for the Hedgehog co-receptor BOC in both the promotion and antagonism of Hedgehog signaling during craniofacial development.

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Hedgehog Signaling in Myeloid Malignancies

Cancers ◽

10.3390/cancers13194888 ◽

2021 ◽

Vol 13 (19) ◽

pp. 4888

Author(s):

Ajay Abraham ◽

William Matsui

Keyword(s):

Clinical Studies ◽

Myeloid Leukemia ◽

Hedgehog Signaling ◽

Treatment Options ◽

Clinical Manifestations ◽

Myeloid Malignancies ◽

Pathway Activation ◽

Wide Range ◽

Hh Signaling

Myeloid malignancies arise from normal hematopoiesis and include several individual disorders with a wide range of clinical manifestations, treatment options, and clinical outcomes. The Hedgehog (HH) signaling pathway is aberrantly activated in many of these diseases, and glasdegib, a Smoothened (SMO) antagonist and HH pathway inhibitor, has recently been approved for the treatment of acute myeloid leukemia (AML). The efficacy of SMO inhibitors in AML suggests that they may be broadly active, but clinical studies in other myeloid malignancies have been largely inconclusive. We will discuss the biological role of the HH pathway in normal hematopoiesis and myeloid malignancies and review clinical studies targeting HH signaling in these diseases. In addition, we will examine SMO-independent pathway activation and highlight potential strategies that may expand the clinical utility of HH pathway antagonists.

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Sonic hedgehog negatively regulates pre-TCR–induced differentiation by a Gli2-dependent mechanism

Blood ◽

10.1182/blood-2008-10-185751 ◽

2009 ◽

Vol 113 (21) ◽

pp. 5144-5156 ◽

Cited By ~ 26

Author(s):

Nicola J. Rowbotham ◽

Ariadne L. Hager-Theodorides ◽

Anna L. Furmanski ◽

Susan E. Ross ◽

Susan V. Outram ◽

...

Keyword(s):

Signal Transduction ◽

Sonic Hedgehog ◽

Hedgehog Signaling ◽

Negative Regulator ◽

Double Positive ◽

Induced Differentiation ◽

Transgenic Expression ◽

Tcr Signal Transduction ◽

Hh Signaling ◽

Dependent Mechanism

Abstract Hedgehog signaling regulates differentiation, survival, and proliferation of the earliest double-negative (DN) thymocytes, but its importance at later stages of T-cell development is controversial. Here we use loss- and gain-of-function mouse models to show that Shh, by signaling directly to the developing thymocyte, is a negative regulator of pre-TCR–induced differentiation from DN to double-positive (DP) cell. When hedgehog signaling was reduced, in the Shh−/− and Gli2−/− thymus, or by T lineage–specific transgenic expression of a transcriptional-repressor form of Gli2 (Gli2ΔC2), differentiation to DP cell after pre-TCR signal transduction was increased. In contrast, when Hh signaling was constitutively activated in thymocytes, by transgenic expression of a constitutive transcriptional-activator form of Gli2 (Gli2ΔN2), the production of DP cells was decreased. Gene expression profiling showed that physiologic Hh signaling in thymocytes maintains expression of the transcription factor FoxA2 on pre-TCR signal transduction.

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Programmed cell death 4 (PDCD4) expression during multistep Barrett's carcinogenesis

Journal of Clinical Pathology ◽

10.1136/jcp.2010.078253 ◽

2010 ◽

Vol 63 (8) ◽

pp. 692-696 ◽

Cited By ~ 28

Author(s):

Matteo Fassan ◽

Marco Pizzi ◽

Giorgio Battaglia ◽

Luciano Giacomelli ◽

Paola Parente ◽

...

Keyword(s):

Cell Death ◽

Programmed Cell Death ◽

Intestinal Metaplasia ◽

Negative Regulator ◽

Pcr Analysis ◽

Low Grade ◽

Cytoplasmic Staining ◽

Programmed Cell Death 4 ◽

Columnar Metaplasia

AimTo test the contribution of programmed cell death 4 (PDCD4) tumour suppressor gene in Barrett's carcinogenesis.MethodsPDCD4 immunohistochemical expression was assessed in 88 biopsy samples obtained from histologically proven long-segment Barrett's mucosa (BM; 25 non-intestinal columnar metaplasia, 25 intestinal metaplasia (IM), 16 low-grade intraepithelial neoplasia (LG-IEN), 12 high-grade IEN (HG-IEN) and 10 Barrett's adenocarcinoma (BAc)). As controls, 25 additional samples of native oesophageal mucosa (N) were obtained from patients with dyspepsia. To further support the data, the expression levels of miR-21, an important PDCD4 expression regulator, in 14 N, 5 HG-IEN and 11 BAc samples were determined by quantitative real-time PCR analysis.ResultsPDCD4 immunostaining decreased progressively and significantly with the progression of the phenotypic changes occurring during Barrett's carcinogenesis (p<0.001). Normal basal squamous epithelial layers featured strong PDCD4 nuclear immunoreaction (mostly coexisting with weak–moderate cytoplasmic staining). Non-intestinal columnar metaplasia and intestinal metaplasia preserved a strong nuclear immunostaining; conversely, a significant decrease in PDCD4 nuclear expression was seen in dysplastic (LG-IEN and HG-IEN) and neoplastic lesions. Weak–moderate cytoplasmic immunostaining was evident in cases of LG-IEN, while HG-IEN and BAc samples showed weak cytoplasmic or no protein expression. As expected, miR-21 expression was significantly upregulated in HG-IEN and BAc samples, consistently with PDCD4 dysregulation.ConclusionsThese data support a significant role for PDCD4 downregulation in the progression of BM to BAc, and confirm miR-21 as a negative regulator of PDCD4 in vivo. Further efforts are needed to validate PDCD4 as a potential prognostic marker in patients with Barrett's oesophagus.

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AKT is involved in granulosa cell autophagy regulation via mTOR signaling during rat follicular development and atresia

Reproduction ◽

10.1530/rep-13-0386 ◽

2014 ◽

Vol 147 (1) ◽

pp. 73-80 ◽

Cited By ~ 43

Author(s):

JongYeob Choi ◽

MinWha Jo ◽

EunYoung Lee ◽

DooSeok Choi

Keyword(s):

Cell Death ◽

Granulosa Cell ◽

Granulosa Cells ◽

Apoptotic Cell ◽

Follicular Development ◽

Negative Regulator ◽

Metabolic Clearance ◽

Akt Inhibitor ◽

Western Blots

In this study, we examined whether granulosa cell autophagy during follicular development and atresia was regulated by the class I phosphoinositide-3 kinase/protein kinase B (AKT) pathway, which is known to control the activity of mammalian target of rapamycin (mTOR), a major negative regulator of autophagy. Ovaries and granulosa cells were obtained using an established gonadotropin-primed immature rat model that induces follicular development and atresia. Autophagy was evaluated by measuring the expression level of microtubule-associated protein light chain 3-II (LC3-II) using western blots and immunohistochemistry. The activity of AKT and mTOR was also examined by observing the phosphorylation of AKT and ribosomal protein S6 kinase (S6K) respectively. After gonadotropin injection, LC3-II expression was suppressed and phosphorylation of AKT and S6K increased in rat granulosa cells. By contrast, gonadotropin withdrawal by metabolic clearance promoted LC3-II expression and decreased phosphorylation of AKT and S6K. In addition,in-vitroFSH treatment of rat granulosa cells also indicated inhibition of LC3-II expression accompanied by a marked increase in phosphorylation of AKT and S6K. Inhibition of AKT phosphorylation using AKT inhibitor VIII suppressed FSH-mediated phosphorylation of S6K, followed by an increase in LC3-II expression. Furthermore, co-treatment with FSH and AKT inhibitor increased the levels of apoptosis and cell death of granulosa cells compared with the single treatment with FSH. Taken together, our findings indicated that AKT-mediated activation of mTOR suppresses granulosa cell autophagy during follicular development and is involved in the regulation of apoptotic cell death.

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