Cancer Stem Cells and Circulatory Tumor Cells Promote Breast Cancer Metastasis

Breast cancer (BC) is a highly metastatic, pathological cancer that significantly affects women worldwide. The mortality rate of BC is related to its heterogeneity, aggressive phenotype, and metastasis. Recent studies have highlighted that the tumor microenvironment (TME) is critical for the interplay between metastasis mediators in BC. BC stem cells, tumor-derived exosomes, circulatory tumor cells (CTCs), and signaling pathways dynamically remodel the TME and promote metastasis. This review examines the cellular and molecular mechanisms governing the epithelial to mesenchymal transition (EMT) that facilitate metastasis. This review also discusses the role of cancer stem cells (CSCs), tumor-derived exosomes, and CTs in promoting BC metastasis. Furthermore, the review emphasizes major signaling pathways that mediate metastasis in BC. Finally, the interplay among CSCs, exosomes, and CTCs in mediating metastasis have been highlighted. Therefore, understanding the molecular cues that mediate the association of CSCs, exosomes, and CTCs in TME helps to optimize systemic therapy to target metastatic BC.     

Oncogenic properties and signaling basis of the PAX8-GLIS3 fusion gene

Hyalinizing trabecular tumors of the thyroid are rare and mostly benign epithelial neoplasms of follicular cell origin, which have recently been shown to be underpinned by the PAX8-GLIS3 fusion gene. In our study, we sought to investigate the potential oncogenic mechanisms of the PAX8-GLIS3 fusion gene. Forced expression of PAX8-GLIS3 was found to increase proliferation, clonogenic potential and migration of human nonmalignant thyroid (Nthy-ori 3-1) and embryonic kidney (HEK-293) cells. Moreover, in xenografts, Nthy-ori 3-1 PAX8-GLIS3 expressing cells generated significantly larger and more proliferative tumors compared to controls. These oncogenic effects were found to be mediated through activation of the Sonic Hedgehog (SHH) pathway. Targeting of smoothened (SMO), a key protein in the SHH pathway, using the small molecule inhibitor Cyclopamine partially reversed the increased proliferation, colony formation and migration in PAX8-GLIS3 expressing cells. Our data demonstrate that the oncogenic effects of the PAX8-GLIS3 fusion gene are, at least in part, due to an increased activation of the SHH pathway.     

野黄芩苷通过hedgehog信号通路抑制结肠肿瘤干细胞分化的研究

该文旨在研究野黄芩苷对结肠肿瘤干细胞体外和体内分化的影响,揭示野黄芩苷基于hedgehog信号通路的抑制结肠肿瘤干细胞分化的作用机制。用3D细胞培养法观察野黄芩苷对结肠肿瘤干细胞HT-29CSC体外生长的影响;用软琼脂克隆形成实验研究野黄芩苷对HT-29CSC细胞转化的影响;用胎牛血清诱导干细胞分化实验,研究野黄芩苷对HT-29CSC细胞体外分化的影响;用qRT-PCR法检测野黄芩苷对HT-29CSC细胞中Lgr5,c-Myc,CK20和Nanog mRNA表达的影响;用Western blot法检测野黄芩苷对HT-29CSC细胞中c-Myc,Gli1,Lgr5蛋白表达的影响。通过裸鼠皮下接种HT-29CSC细胞建立肿瘤干细胞体内分化成瘤模型,研究野黄芩苷对裸鼠体质量和HT-29CSC细胞分化成瘤的影响;用qRT-PCR法检测肿瘤组织中CD133,Lgr5,Gli1,Ptch1,c-Myc,Ki-67,CK20,Nanog mRNA表达水平;用Western blot法及免疫组织化学法检测肿瘤组织中c-Myc,Gli1,Lgr5,CD133,Ki-67蛋白表达水平。体外研究表明,野黄芩苷能够抑制HT-29CSC细胞生长、转化与分化,同时显著下调HT-29CSC细胞中Lgr5,c-Myc,CK20,Nanog mRNA水平和c-Myc,Gli1,Lgr5蛋白表达。动物实验表明,野黄芩苷显著抑制裸鼠皮下HT-29CSC细胞分化成瘤,并且下调肿瘤组织中CD133,Lgr5,Gli1,Ptch1,c-Myc,Ki-67,CK20,Nanog mRNA表达和c-Myc,Gli1,Lgr5,CD133,Ki-67蛋白表达。综上所述,野黄芩苷能够抑制结肠肿瘤干细胞的体外和体内分化,其作用机制在于下调hedgehog信号通路活性。     

A familial Sonic Hedgehog (SHH) stop-gain mutation associated with agenesis of the corpus callosum,mild intellectual disability and facial dysmorphism

BackgroundAgenesis of the corpus callosum (ACC) is a relatively common brain malformation in children with developmental disabilities, caused by mutations in many genes. These genetic causes are characterized by their extreme heterogeneity with more than 300 causative genes identified to date.Case reportWe describe two new cases from a three-generation family with ACC and a de novo mutation of the sonic hedgehog (SHH) gene. The affected family members had mild intellectual disability, broad forehead, and widely spaced eyes. A next-generation sequencing (NGS) approach revealed a stop-gain mutation (NM_000193.2:c.1300_1301insA p.Trp434Ter) of the SHH gene; it is the first family to report ACC associated with a single SHH gene mutation.ConclusionACC with mild intellectual disability and facial dysmorphism may be caused by a mutation in SHH, but further research investigating the genotype-phenotype correlation of SHH mutations is required.     

Spatiotemporal map of key signaling factors during early penis development

The formation of the external genitalia is a highly complex developmental process, considering it involves a wide range of cell types and results in sexually dimorphic outcomes. Development is controlled by several secreted signalling factors produced in complex spatiotemporal patterns, including the hedgehog (HH), bone morphogenic protein (BMP), fibroblast growth factor (FGF) and WNT signalling families. Many of these factors act on or are influenced by the actions of the androgen receptor (AR) that is critical to masculinisation. This complexity of expression makes it difficult to conceptualise patterns of potential importance. Mapping expression during key stages of development is needed to develop a comprehensive model of how different cell types interact in formation of external genitalia, and the global regulatory networks at play. This is particularly true in light of the sensitivity of this process to environmental disruption during key stages of development. The goal of this review is to integrate all recent studies on gene expression in early penis development to create a comprehensive spatiotemporal map. This serves as a resource to aid in visualising potentially significant interactions involved in external genital development.     

miR-218 inhibits multidrug resistance (MDR) of gastric cancer cells by targeting Hedgehog/smoothened

Multidrug resistance (MDR) is the main obstacle to successful chemotherapy for patients with gastric cancer. The microRNA miR-218 influences various pathobiological processes in gastric cancer, and its down-regulation in this disease raises the question of whether it normally inhibits MDR. In this study we observed that two MDR gastric cancer cell lines showed lower expression of miR-218 compared with their chemosensitive parental cell line. Overexpressing miR-218 chemosensitizes gastric cancer cells, slowed efflux of adriamycin, and accelerated drug-induced apoptosis. We identified the smoothened (SMO) gene as a functional target of miR-218, and found that SMO overexpression counteracts the chemosensitizing effects of miR-218. These findings suggest that miR-218 inhibits MDR of gastric cancer cells by down-regulating SMO expression.