The developmental protein Numb is a major determinant of binary cell fates. It is also required for the differentiation of cerebellar granule cell progenitors (GCPs) at a stage of development responsive to the morphogenic glycoprotein Hedehog. Hedgehog signalling is crucial for the physiological maintenance and self-renewal of neural stem cells and its deregulation is responsible for their progression towards tumorigenesis. The mechanisms that inhibit this pathway during the differentiation stage are poorly understood. Here, we identify Numb as a Hedgehog-pathway inhibitor that is downregulated in early GCPs and GCP-derived cancer cells. We demonstrate that the Hedgehog transcription factor Gli1 is targeted by Numb for Itch-dependent ubiquitination, which suppresses Hedgehog signals, thus arresting growth and promoting cell differentiation. This novel Numb-dependent regulatory loop may limit the extent and duration of Hedgehog signalling during neural-progenitor differentiation, and its subversion may be a relevant event in brain tumorigenesis.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1038/ncb1510 | DOI Listing |
Sci Rep
December 2024
Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
Lung cancer ranks as the most prevalent malignant neoplasm worldwide, contributing significantly to cancer-related mortality. Stemness is a well-recognized factor underlying radiotherapy resistance, recurrence and metastasis in non-small-cell lung cancer (NSCLC) patients. Our prior investigations have established the role of IQ motif containing GTPase-activating protein 3 (IQGAP3) in mediating radiotherapy resistance in lung cancer, but its impact on lung cancer stemness remains unexplored.
View Article and Find Full Text PDFCongenit Anom (Kyoto)
December 2024
Department of Molecular Craniofacial Embryology and Oral Histology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan.
Sonic hedgehog (Shh) is expressed in the oropharyngeal epithelium, including the frontonasal ectodermal zone (FEZ), which is defined as the boundary between Shh and Fgf8 expression domains in the frontonasal epithelium. To investigate the role of SHH signaling from the oropharyngeal epithelium, we generated mice in which Shh expression is specifically deleted in the oropharyngeal epithelium (Isl1-Cre; Shh). In the mutant mouse, Shh expression was excised in the oropharyngeal epithelium as well as FEZ and ventral forebrain, consistent with the expression pattern of Isl1.
View Article and Find Full Text PDFFront Neurosci
December 2024
German Center for Neurodegenerative Diseases (DZNE), Tübingen, Germany.
Background: Extracellular vesicles are easily accessible in various biofluids and allow the assessment of disease-related changes in the proteome. This has made them a promising target for biomarker studies, especially in the field of neurodegeneration where access to diseased tissue is very limited. Genetic variants in the LRRK2 gene have been linked to both familial and sporadic forms of Parkinson's disease.
View Article and Find Full Text PDFBiol Direct
December 2024
Department of Obstetrics and Gynecology, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China.
Background: Intrauterine adhesion (IUA) is a common cause of clinically refractory infertility, and there exists significant heterogeneity in the treatment outcomes among IUA patients with the similar severity after transcervical resection of adhesion(TCRA). The underlying mechanism of different treatment outcomes occur remains elusive, and the precise contribution of various cell subtypes in this process remains uncertain.
Results: Here, we performed single-cell transcriptome sequencing on 10 human endometrial samples to establish a single-cell atlas differences between patients who responded to estrogen therapy and those who did not.
Adv Sci (Weinh)
December 2024
Department of Pathology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, China.
There is an urgent necessity to devise efficient tactics to tackle the inevitable development of resistance to osimertinib, which is a third-generation epidermal growth factor receptor (EGFR) inhibitor used in treating EGFR-mutant nonsmall cell lung cancer (NSCLC). This study demonstrates that combining itraconazole with osimertinib synergistically reduces the proliferation and migration, enhances the apoptosis of osimertinib-resistant cells, and effectively inhibits the growth of osimertinib-resistant tumors. Mechanistically, itraconazole combined with osimertinib promotes the proteasomal degradation of sonic hedgehog (SHH), resulting in inactivation of the SHH/Dual-specificity phosphatase 13B (DUSP13B)/p-STAT3 and Hedgehog pathways, suppressing Myc proto-oncogene protein (c-Myc).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!