In non-mammalian vertebrates, the relatively homogeneous population of retinal ganglion cells (RGCs) differentiates and projects entirely to the contralateral side of the brain under the influence of sonic hedgehog (Shh). In mammals, by contrast, there are two different RGC types: the Zic2-positive ipsilateral projecting and the Isl2-positive contralateral projecting. We asked whether the axons...

Sonic hedgehog (Shh) signaling controls many aspects of human development, regulates cell growth and differentiation in adult tissues, and is activated in a number of malignancies. Rheumatoid arthritis (RA) is characterized by chronic synovitis and pannus formation associated with activation of fibroblast-like synoviocytes (FLS). We investigated whether Shh signaling plays a role in the prolife...

Cerebellar granule cells are the most abundant neurons in the brain, and granule cell precursors (GCPs) are a common target of transformation in the pediatric brain tumor medulloblastoma. Proliferation of GCPs is regulated by the secreted signaling molecule Sonic hedgehog (Shh), but the mechanisms by which Shh controls proliferation of GCPs remain inadequately understood. We used DNA microarray...

Sonic hedgehog (SHh) signaling is essential for normal development of the human gastrointestinal (GI) tract and is reported to be aberrantly activated in GI cancers. However, the association between SHh signaling and extrahepatic biliary tract cancer is not clearly understood. In this study, we evaluated the activities of SHh family proteins and t...

Division of the telencephalic vesicle into hemispheres and specification of the cerebral cortex are key stages in forebrain development. We investigate the interplay in these processes of Sonic hedgehog (Shh), fibroblast growth factors (Fgfs), and the transcription factor Gli3, which in its repressor form (Gli3R) antagonizes Shh signaling and downregulates expression of several Fgf genes. Contr...

The mammalian secondary palate arises by outgrowth from the oral side of the paired maxillary processes flanking the primitive oral cavity. Palatal growth depends on reciprocal interactions between the oral ectoderm and the underlying neural-crest-derived mesenchyme. Previous studies have implicated sonic hedgehog (Shh) as an important epithelial signal for regulating palatal growth. However, t...

Sonic hedgehog (Shh) is not only essential to the development of the gastrointestinal tract, but is also necessary to maintain the characteristic acid-secreting phenotype of the adult stomach. Gastrin is the only hormone capable of stimulating gastric acid and is thus required to maintain functional parietal cells. We have shown previously that gastrin-null mice display gastric atrophy and meta...

BACKGROUND Sonic hedgehog (Shh) signaling regulates cell growth during embryonic development, tissue homeostasis and tumorigenesis. Concentration-dependent cellular responses to secreted Shh protein are essential for tissue patterning. Shh ligand is covalently modified by two lipid moieties, cholesterol and palmitate, and their hydrophobic properties are known to govern the cellular release and...

AIMS This study aimed to examine the expression of Sonic hedgehog (SHH) signalling proteins in retinoblastoma and to evaluate its clinical significance. METHODS Seventy-nine enucleated retinoblastoma tumours were investigated immunohistochemically using antibodies against SHH pathway proteins, such as SHH, glioma-associated oncogene homologue (GLI) 1, GLI2, GLI3 and ABC binding cassette G2 (A...

BACKGROUND Sonic hedgehog (Shh) signaling regulates cell proliferation during vertebrate development via induction of cell-cycle regulator gene expression or activation of other signalling pathways, prevents cell death by an as yet unclear mechanism and is required for differentiation of retinal cell types. Thus, an unsolved question is how the same signalling molecule can regulate such distinc...