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Du S, Wang Y, Lu F, Zhou W. Effects of MEK1/2 inhibitor U0126 on FGF10-enhanced buffalo oocyte maturation in vitro. Reprod Biol 2024; 24:100883. [PMID: 38643607 DOI: 10.1016/j.repbio.2024.100883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 03/31/2024] [Accepted: 04/07/2024] [Indexed: 04/23/2024]
Abstract
Fibroblast growth factor 10 (FGF10) plays critical roles in oocyte maturation and embryonic development; however, the specific pathway by which FGF10 promotes in vitro maturation of buffalo oocytes remains elusive. The present study was aimed at investigating the mechanism underlying effects of the FGF10-mediated extracellular regulated protein kinases (ERK) pathway on oocyte maturation and embryonic development in vitro. MEK1/2 (mitogen-activated protein kinase kinase) inhibitor U0126, alone or in combination with FGF10, was added to the maturation culture medium during maturation of the cumulus oocyte complex. Morphological observations, orcein staining, apoptosis detection, and quantitative real-time PCR were performed to evaluate oocyte maturation, embryonic development, and gene expression. U0126 affected oocyte maturation and embryonic development in vitro by substantially reducing the nuclear maturation of oocytes and expansion of the cumulus while increasing the apoptosis of cumulus cells. However, it did not have a considerable effect on glucose metabolism. These findings suggest that blocking the MEK/ERK pathway is detrimental to the maturation and embryonic development potential of buffalo oocytes. Overall, FGF10 may regulate the nuclear maturation of oocytes and cumulus cell expansion and apoptosis but not glucose metabolism through the MEK/ERK pathway. Our findings indicate that FGF10 regulates resumption of meiosis and expansion and survival of cumulus cells via MEK/ERK signaling during in vitro maturation of buffalo cumulus oocyte complexes. Elucidation of the mechanism of action of FGF10 and insights into oocyte maturation should advance buffalo breeding. Further studies should examine whether enhancement of MEK/ERK signaling improves embryonic development in buffalo.
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Affiliation(s)
- Shanshan Du
- Department of Reproductive Medicine, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China; State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Animal Reproduction Institute, Guangxi University, Nanning, China.
| | - Yanxin Wang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Animal Reproduction Institute, Guangxi University, Nanning, China
| | - Fenghua Lu
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Animal Reproduction Institute, Guangxi University, Nanning, China
| | - Wenting Zhou
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, Animal Reproduction Institute, Guangxi University, Nanning, China
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2
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Lan Q, Trela E, Lindström R, Satta JP, Kaczyńska B, Christensen MM, Holzenberger M, Jernvall J, Mikkola ML. Mesenchyme instructs growth while epithelium directs branching in the mouse mammary gland. eLife 2024; 13:e93326. [PMID: 38441552 PMCID: PMC10959526 DOI: 10.7554/elife.93326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 03/04/2024] [Indexed: 03/23/2024] Open
Abstract
The mammary gland is a unique organ that undergoes dynamic alterations throughout a female's reproductive life, making it an ideal model for developmental, stem cell and cancer biology research. Mammary gland development begins in utero and proceeds via a quiescent bud stage before the initial outgrowth and subsequent branching morphogenesis. How mammary epithelial cells transit from quiescence to an actively proliferating and branching tissue during embryogenesis and, importantly, how the branch pattern is determined remain largely unknown. Here, we provide evidence indicating that epithelial cell proliferation and onset of branching are independent processes, yet partially coordinated by the Eda signaling pathway. Through heterotypic and heterochronic epithelial-mesenchymal recombination experiments between mouse mammary and salivary gland tissues and ex vivo live imaging, we demonstrate that unlike previously concluded, the mode of branching is an intrinsic property of the mammary epithelium whereas the pace of growth and the density of ductal tree are determined by the mesenchyme. Transcriptomic profiling and ex vivo and in vivo functional studies in mice disclose that mesenchymal Wnt/ß-catenin signaling, and in particular IGF-1 downstream of it critically regulate mammary gland growth. These results underscore the general need to carefully deconstruct the different developmental processes producing branched organs.
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Affiliation(s)
- Qiang Lan
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, Helsinki Institute of Life Science (HiLIFE), University of HelsinkiHelsinkiFinland
| | - Ewelina Trela
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, Helsinki Institute of Life Science (HiLIFE), University of HelsinkiHelsinkiFinland
| | - Riitta Lindström
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, Helsinki Institute of Life Science (HiLIFE), University of HelsinkiHelsinkiFinland
| | - Jyoti Prabha Satta
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, Helsinki Institute of Life Science (HiLIFE), University of HelsinkiHelsinkiFinland
| | - Beata Kaczyńska
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, Helsinki Institute of Life Science (HiLIFE), University of HelsinkiHelsinkiFinland
| | - Mona M Christensen
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, Helsinki Institute of Life Science (HiLIFE), University of HelsinkiHelsinkiFinland
| | | | - Jukka Jernvall
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, Helsinki Institute of Life Science (HiLIFE), University of HelsinkiHelsinkiFinland
- Department of Geosciences and Geography, University of HelsinkiHelsinkiFinland
| | - Marja L Mikkola
- Cell and Tissue Dynamics Research Program, Institute of Biotechnology, Helsinki Institute of Life Science (HiLIFE), University of HelsinkiHelsinkiFinland
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3
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Mieczkowski K, Popeda M, Lesniak D, Sadej R, Kitowska K. FGFR2 Controls Growth, Adhesion and Migration of Nontumorigenic Human Mammary Epithelial Cells by Regulation of Integrin β1 Degradation. J Mammary Gland Biol Neoplasia 2023; 28:9. [PMID: 37191822 DOI: 10.1007/s10911-023-09537-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 04/26/2023] [Indexed: 05/17/2023] Open
Abstract
The role of fibroblast growth factor receptor 2 (FGFR2), an important mediator of stromal paracrine and autocrine signals, in mammary gland morphogenesis and breast cancer has been extensively studied over the last years. However, the function of FGFR2 signalling in the initiation of mammary epithelial oncogenic transformation remains elusive. Here, FGFR2-dependent behaviour of nontumorigenic model of mammary epithelial cells was studied. In vitro analyses demonstrated that FGFR2 regulates epithelial cell communication with extracellular matrix (ECM) proteins. Silencing of FGFR2 significantly changed the phenotype of cell colonies in three-dimensional cultures, decreased integrins α2, α5 and β1 protein levels and affected integrin-driven processes, such as cell adhesion and migration. More detailed analysis revealed the FGFR2 knock-down-induced proteasomal degradation of integrin β1. Analysis of RNA-seq databases showed significantly decreased FGFR2 and ITGB1 mRNA levels in breast tumour samples, when compared to non-transformed tissues. Additionally, high risk healthy individuals were found to have disrupted correlation profiles of genes associated with FGFR2 and integrin signalling, cell adhesion/migration and ECM remodelling. Taken together, our results strongly suggest that FGFR2 loss with concomitant integrin β1 degradation is responsible for deregulation of epithelial cell-ECM interactions and this process may play an important role in the initiation of mammary gland epithelial tumorigenesis.
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Affiliation(s)
- Kamil Mieczkowski
- Department of Molecular Enzymology and Oncology, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Gdansk, Poland.
- Laboratory Genes and Disease, Department of Dermatology, Medical University of Vienna, Vienna, Austria.
| | - Marta Popeda
- Laboratory of Translational Oncology, Intercollegiate Faculty of Biotechnology, Medical University of Gdansk, Gdansk, Poland
- Department of Pathomorphology, Medical University of Gdansk, Gdansk, Poland
| | - Dagmara Lesniak
- Department of Molecular Enzymology and Oncology, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Gdansk, Poland
| | - Rafal Sadej
- Department of Molecular Enzymology and Oncology, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Gdansk, Poland
| | - Kamila Kitowska
- Department of Molecular Enzymology and Oncology, Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Gdansk, Poland.
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4
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Sokolov D, Gorshkova A, Markova K, Milyutina Y, Pyatygina K, Zementova M, Korenevsky A, Mikhailova V, Selkov S. Natural Killer Cell Derived Microvesicles Affect the Function of Trophoblast Cells. MEMBRANES 2023; 13:213. [PMID: 36837716 PMCID: PMC9963951 DOI: 10.3390/membranes13020213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 02/02/2023] [Accepted: 02/06/2023] [Indexed: 06/18/2023]
Abstract
The interaction of natural killer (NK) and trophoblast cells underlies the formation of immune tolerance in the mother-fetus system and the maintenance of the physiological course of pregnancy. In addition, NK cells affect the function of trophoblast cells, interacting with them via the receptor apparatus and through the production of cytokines. Microvesicles (MVs) derived from NK cells are able to change the function of target cells. However, in the overall pattern of interactions between NK cells and trophoblasts, the possibility that both can transmit signals to each other via MVs has not been taken into account. Therefore, the aim of this study was to assess the effect of NK cell-derived MVs on the phenotype, proliferation, and migration of trophoblast cells and their expression of intracellular messengers. We carried out assays for the detection of content transferred from MV to trophoblasts. We found that NK cell-derived MVs did not affect the expression of CD54, CD105, CD126, CD130, CD181, CD119, and CD120a receptors in trophoblast cells or lead to the appearance of CD45 and CD56 receptors in the trophoblast membrane. Further, the MVs reduced the proliferation but increased the migration of trophoblasts with no changes to their viability. Incubation of trophoblast cells in the presence of MVs resulted in the activation of STAT3 via pSTAT3(Ser727) but not via pSTAT3(Tyr705). The treatment of trophoblasts with MVs did not result in the phosphorylation of STAT1 and ERK1/2. The obtained data indicate that NK cell-derived MVs influence the function of trophoblast cells, which is accompanied by the activation of STAT3 signaling.
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5
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Yu L, Yi X, Yu C, Wang F, Tan X. Fibroblast growth factor 10 ameliorates renal ischaemia-reperfusion injury by attenuating mitochondrial damage. Clin Exp Pharmacol Physiol 2023; 50:59-67. [PMID: 36111374 DOI: 10.1111/1440-1681.13724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 09/07/2022] [Accepted: 09/13/2022] [Indexed: 12/13/2022]
Abstract
Ischaemia-reperfusion (I/R) injury is one of the leading causes of acute kidney injury (AKI). Its pathologic mechanism is quite complex, involving oxidative stress, inflammatory response, autophagy, and apoptosis. Fibroblast growth factor 10 (FGF10) and 5-hydroxydecanoate (5-HD) play essential roles in kidney injury. Rats were divided into four groups: (i) sham group, sham-operated animals with an unconstructed renal artery; (ii) I/R group, kidneys were subjected to 50 min of ischaemia followed by reperfusion for 2 days; (iii) I/R + FGF10 group, animals treated with 0.5 mg/kg FGF10 (i.p.) 1 h before ischaemia; and (iv) 5-HD group, animals treated with 5 mg/kg 5-HD (i.m.) 30 min before FGF10 treatment. Renal injury, apoptosis damage, mitochondrial oxidative damage, mitochondrial membrane potential (MMP), and expression of the ATP-sensitive K+ (KATP) channel subunit Kir6.2 were evaluated. FGF10 treatment significantly alleviated I/R-induced elevation in the serum creatinine level and the number of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling-positive tubular cells in the kidney. In addition, FGF10 dramatically ameliorated renal mitochondrial-related damage, including reducing mitochondrial-dependent apoptosis, alleviating oxidative stress, maintaining the mitochondrial membrane potential, and opening the mitochondrial KATP channels. The protective effect of FGF10 was significantly compromised by the ATP-dependent potassium channel blocker 5-HD. Our data suggest that FGF10 offers effective protection against I/R and improves animal survival by attenuating mitochondrial damage.
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Affiliation(s)
- Lixia Yu
- Department of Pharmacy, Xixi Hospital of Hangzhou, Zhejiang, China
| | - Xiaojiao Yi
- Department of Pharmacy, Xixi Hospital of Hangzhou, Zhejiang, China
| | - Cailong Yu
- Department of Pharmacy, Xixi Hospital of Hangzhou, Zhejiang, China
| | - Fugen Wang
- Department of Pharmacy, Xixi Hospital of Hangzhou, Zhejiang, China
| | - Xiaohua Tan
- Department of Pathology, School of Basic Medicine, Qingdao University, Qingdao, China
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6
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Al-Khaldi S, Almohanna F, Barnawi R, Fallatah M, Islam SS, Ghebeh H, Al-Alwan M. Fascin is essential for mammary gland lactogenesis. Dev Biol 2022; 492:25-36. [PMID: 36152869 DOI: 10.1016/j.ydbio.2022.09.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 05/29/2022] [Accepted: 09/16/2022] [Indexed: 11/03/2022]
Abstract
Fascin expression has commonly been observed in certain subtypes of breast cancer, where its expression is associated with poor clinical outcome. However, its role in normal mammary gland development has not been elucidated. Here, we used a fascin knockout mouse model to assess its role in normal mammary gland morphogenesis and lactation. Fascin knockout was not embryonically lethal, and its effect on the litter size or condition at birth was minimal. However, litter survival until the weaning stage significantly depended on fascin expression solely in the nursing dams. Accordingly, pups that nursed from fascin-/- dams had smaller milk spots in their abdomen, suggesting a lactation defect in the nursing dams. Mammary gland whole-mounts of pregnant and lactating fascin-/- mice showed significantly reduced side branching and alveologenesis. Despite a typical composition of basal, luminal, and stromal subsets of mammary cells and normal ductal architecture of myoepithelial and luminal layers, the percentage of alveolar progenitors (ALDH+) in fascin-/- epithelial fraction was significantly reduced. Further in-depth analyses of fascin-/- mammary glands showed a significant reduction in the expression of Elf5, the master regulator of alveologenesis, and a decrease in the activity of its downstream target p-STAT5. In agreement, there was a significant reduction in the expression of the milk proteins, whey acidic protein (WAP), and β-casein in fascin-/- mammary glands. Collectively, our data demonstrate, for the first time, the physiological role of fascin in normal mammary gland lactogenesis, an addition that could reveal its contribution to breast cancer initiation and progression.
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Affiliation(s)
- Samiyah Al-Khaldi
- National Center for Biotechnology, Life Science and Environment Research Institute, King Abdulaziz City for Sciences and Technology, Riyadh, Saudi Arabia.
| | | | | | - Mohannad Fallatah
- National Center for Biotechnology, Life Science and Environment Research Institute, King Abdulaziz City for Sciences and Technology, Riyadh, Saudi Arabia.
| | - Syed S Islam
- Molecular Oncology, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia; Collage of Medicine, Al-Faisal University, Riyadh, Saudi Arabia.
| | - Hazem Ghebeh
- Stem Cell and Tissue Re-Engineering Program, Saudi Arabia; Collage of Medicine, Al-Faisal University, Riyadh, Saudi Arabia.
| | - Monther Al-Alwan
- Stem Cell and Tissue Re-Engineering Program, Saudi Arabia; Collage of Medicine, Al-Faisal University, Riyadh, Saudi Arabia.
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7
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Ehnes DD, Alghadeer A, Hanson-Drury S, Zhao YT, Tilmes G, Mathieu J, Ruohola-Baker H. Sci-Seq of Human Fetal Salivary Tissue Introduces Human Transcriptional Paradigms and a Novel Cell Population. FRONTIERS IN DENTAL MEDICINE 2022; 3:887057. [PMID: 36540608 PMCID: PMC9762771 DOI: 10.3389/fdmed.2022.887057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/17/2023] Open
Abstract
Multiple pathologies and non-pathological factors can disrupt the function of the non-regenerative human salivary gland including cancer and cancer therapeutics, autoimmune diseases, infections, pharmaceutical side effects, and traumatic injury. Despite the wide range of pathologies, no therapeutic or regenerative approaches exist to address salivary gland loss, likely due to significant gaps in our understanding of salivary gland development. Moreover, identifying the tissue of origin when diagnosing salivary carcinomas requires an understanding of human fetal development. Using computational tools, we identify developmental branchpoints, a novel stem cell-like population, and key signaling pathways in the human developing salivary glands by analyzing our human fetal single-cell sequencing data. Trajectory and transcriptional analysis suggest that the earliest progenitors yield excretory duct and myoepithelial cells and a transitional population that will yield later ductal cell types. Importantly, this single-cell analysis revealed a previously undescribed population of stem cell-like cells that are derived from SD and expresses high levels of genes associated with stem cell-like function. We have observed these rare cells, not in a single niche location but dispersed within the developing duct at later developmental stages. Our studies introduce new human-specific developmental paradigms for the salivary gland and lay the groundwork for the development of translational human therapeutics.
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Affiliation(s)
- Devon Duron Ehnes
- Department of Biochemistry, School of Medicine, University of Washington, Seattle, WA, United States
- Institute for Stem Cells and Regenerative Medicine, School of Medicine, University of Washington, Seattle, WA, United States
| | - Ammar Alghadeer
- Department of Biochemistry, School of Medicine, University of Washington, Seattle, WA, United States
- Institute for Stem Cells and Regenerative Medicine, School of Medicine, University of Washington, Seattle, WA, United States
- Department of Biomedical Dental Sciences, College of Dentistry, Imam Abdulrahman bin Faisal University, Dammam, Saudi Arabia
| | - Sesha Hanson-Drury
- Department of Biochemistry, School of Medicine, University of Washington, Seattle, WA, United States
- Institute for Stem Cells and Regenerative Medicine, School of Medicine, University of Washington, Seattle, WA, United States
- Department of Oral Health Sciences, School of Dentistry, University of Washington, Seattle, WA, United States
| | - Yan Ting Zhao
- Department of Biochemistry, School of Medicine, University of Washington, Seattle, WA, United States
- Institute for Stem Cells and Regenerative Medicine, School of Medicine, University of Washington, Seattle, WA, United States
- Department of Oral Health Sciences, School of Dentistry, University of Washington, Seattle, WA, United States
| | - Gwen Tilmes
- Institute for Stem Cells and Regenerative Medicine, School of Medicine, University of Washington, Seattle, WA, United States
| | - Julie Mathieu
- Institute for Stem Cells and Regenerative Medicine, School of Medicine, University of Washington, Seattle, WA, United States
- Department of Comparative Medicine, University of Washington, Seattle, WA, United States
| | - Hannele Ruohola-Baker
- Department of Biochemistry, School of Medicine, University of Washington, Seattle, WA, United States
- Institute for Stem Cells and Regenerative Medicine, School of Medicine, University of Washington, Seattle, WA, United States
- Department of Biomedical Dental Sciences, College of Dentistry, Imam Abdulrahman bin Faisal University, Dammam, Saudi Arabia
- Department of Bioengineering, University of Washington, Seattle, WA, United States
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8
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Growth factor dependency in mammary organoids regulates ductal morphogenesis during organ regeneration. Sci Rep 2022; 12:7200. [PMID: 35504930 PMCID: PMC9065107 DOI: 10.1038/s41598-022-11224-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 04/20/2022] [Indexed: 12/28/2022] Open
Abstract
Signaling pathways play an important role in cell fate determination in stem cells and regulate a plethora of developmental programs, the dysregulation of which can lead to human diseases. Growth factors (GFs) regulating these signaling pathways therefore play a major role in the plasticity of adult stem cells and modulate cellular differentiation and tissue repair outcomes. We consider murine mammary organoid generation from self-organizing adult stem cells as a tool to understand the role of GFs in organ development and tissue regeneration. The astounding capacity of mammary organoids to regenerate a gland in vivo after transplantation makes it a convenient model to study organ regeneration. We show organoids grown in suspension with minimal concentration of Matrigel and in the presence of a cocktail of GFs regulating EGF and FGF signaling can recapitulate key epithelial layers of adult mammary gland. We establish a toolkit utilizing in vivo whole animal imaging and ultrasound imaging combined with ex vivo approaches including tissue clearing and confocal imaging to study organ regeneration and ductal morphogenesis. Although the organoid structures were severely impaired in vitro when cultured in the presence of individual GFs, ex vivo imaging revealed ductal branching after transplantation albeit with significantly reduced number of terminal end buds. We anticipate these imaging modalities will open novel avenues to study mammary gland morphogenesis in vivo and can be beneficial for monitoring mammary tumor progression in pre-clinical and clinical settings.
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Shi Q, Wang Q, Liu L, Chen J, Wang B, Bellusci S, Chen C, Dong N. FGF10 protects against particulate matter (PM)-induced lung injury via regulation of endoplasmic reticulum stress. Int Immunopharmacol 2022; 105:108552. [PMID: 35114441 DOI: 10.1016/j.intimp.2022.108552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Revised: 01/08/2022] [Accepted: 01/16/2022] [Indexed: 11/05/2022]
Abstract
Exposure of the lungs to particulate matter (PM) leads to the development of respiratory disease and involves mechanisms such as oxydative stress, mitochondrial dysfunction and endoplasmic reticulum (ER) stress. However, there are no effective therapies to treat PM-induced lung diseases. Fibroblast growth factor 10 (FGF10) is a multifunctional growth factor mediating mesenchymal-to-epithelial signaling and displaying a significant therapeutic potential following injury. The present research aims to investigate the regulatory mechanism of FGF10 on ER stress in PM-induced lung injury. PM-induced lung injury leads to peribronchial wall thickening and marked infiltration of inflammatory cells which is associated with increased secretion of inflammatory cytokines. The results show that FGF10 treatment attenuates PM-induced lung injury in vivo and reversed ER stress protein GRP78 and CHOP levels. Moreover, comparison of human bronchial epithelial cells cultured with PM and FGF10 vs PM alone shows sustained cell proliferation and restrained secretion of inflammatory cytokines supporting FGF10's protective role. Significantly, both ERK1/2 and PI3K/AKT inhibitors largely abolished the impact of FGF10 on PM-induced ER stress. Taken together, both in vivo and in vitro experiments showed that FGF10, via the activation of ERK1/2 and PI3K/AKT signaling, protects against PM-induced lung injury through the regulation of ER stress. Therefore, FGF10 represents a potential therapy for PM-induced lung injury.
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Affiliation(s)
- Qiangqiang Shi
- Key Laboratory of Interventional Pulmonology of Zhejiang Province, Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325015, China
| | - Qiang Wang
- Key Laboratory of Interventional Pulmonology of Zhejiang Province, Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325015, China
| | - Li Liu
- Key Laboratory of Interventional Pulmonology of Zhejiang Province, Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325015, China
| | - Junjie Chen
- Key Laboratory of Interventional Pulmonology of Zhejiang Province, Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325015, China
| | - Beibei Wang
- Key Laboratory of Interventional Pulmonology of Zhejiang Province, Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325015, China
| | - Saverio Bellusci
- Cardio-Pulmonary Institute (CPI) and Department of Pulmonary and Critical Care Medicine and Infectious Diseases, Universities of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Justus-Liebig University Giessen, 35392, Giessen, Germany.
| | - Chengshui Chen
- Key Laboratory of Interventional Pulmonology of Zhejiang Province, Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325015, China.
| | - Nian Dong
- Key Laboratory of Interventional Pulmonology of Zhejiang Province, Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325015, China.
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10
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Francavilla C, O'Brien CS. Fibroblast growth factor receptor signalling dysregulation and targeting in breast cancer. Open Biol 2022; 12:210373. [PMID: 35193394 PMCID: PMC8864352 DOI: 10.1098/rsob.210373] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Accepted: 01/20/2022] [Indexed: 01/07/2023] Open
Abstract
Fibroblast Growth Factor Receptor (FGFR) signalling plays a critical role in breast embryonal development, tissue homeostasis, tumorigenesis and metastasis. FGFR, its numerous FGF ligands and signalling partners are often dysregulated in breast cancer progression and are one of the causes of resistance to treatment in breast cancer. Furthermore, FGFR signalling on epithelial cells is affected by signals from the breast microenvironment, therefore increasing the possibility of breast developmental abnormalities or cancer progression. Increasing our understanding of the multi-layered roles of the complex family of FGFRs, their ligands FGFs and their regulatory partners may offer novel treatment strategies for breast cancer patients, as a single agent or rational co-target, which will be explored in depth in this review.
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Affiliation(s)
- Chiara Francavilla
- Division of Molecular and Cellular Function, School of Biological Science, Faculty of Biology, Medicine and Health (FBMH), University of Manchester, Manchester M13 9PT, UK
- The Manchester Breast Centre, University of Manchester, Wilmslow Road, Manchester M20 4GJ, UK
| | - Ciara S. O'Brien
- The Christie Hospital NHS Foundation Trust, Wilmslow Road, Manchester M20 2BX, UK
- The Manchester Breast Centre, University of Manchester, Wilmslow Road, Manchester M20 4GJ, UK
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11
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Wu X, Ayalew W, Chu M, Pei J, Liang C, Bao P, Guo X, Yan P. Characterization of RNA Editome in the Mammary Gland of Yaks during the Lactation and Dry Periods. Animals (Basel) 2022; 12:ani12020207. [PMID: 35049829 PMCID: PMC8773173 DOI: 10.3390/ani12020207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 01/01/2022] [Accepted: 01/14/2022] [Indexed: 12/03/2022] Open
Abstract
Simple Summary In order to study the influence of RNA editing sites on lactation and mammary gland development process in yaks, we comprehensively characterized the RNA editome of the yak mammary gland during the lactation period and dry period by using the transcriptome and genome sequencing data. The results revealed 82,872 nonredundant RNA editing sites, 14,159 of which were differentially edited between the lactation period and dry period. Enrichment analysis showed that the genes harboring differential editing sites were mainly associated with mammary gland development-related pathways, such as MAPK pathway, PI3K-Akt pathway, FoxO signaling pathway, GnRH signaling pathway, and focal adhesion pathway. Our findings offer some novel insights into the RNA editing function in the mammary gland of yaks. Abstract The mammary gland is a complicated organ comprising several types of cells, and it undergoes extensive morphogenetic and metabolic changes during the female reproductive cycle. RNA editing is a posttranscriptional modification event occurring at the RNA nucleotide level, and it drives transcriptomic and proteomic diversities, with potential functional consequences. RNA editing in the mammary gland of yaks, however, remains poorly understood. Here, we used REDItools to identify RNA editing sites in mammary gland tissues in yaks during the lactation period (LP, n = 2) and dry period (DP, n = 3). Totally, 82,872 unique RNA editing sites were identified, most of which were detected in the noncoding regions with a low editing degree. In the coding regions (CDS), we detected 5235 editing sites, among which 1884 caused nonsynonymous amino acid changes. Of these RNA editing sites, 486 were found to generate novel possible miRNA target sites or interfere with the initial miRNA binding sites, indicating that RNA editing was related to gene regulation mediated by miRNA. A total of 14,159 RNA editing sites (involving 3238 common genes) showed a significant differential editing level in the LP when compared with that in the DP through Tukey’s Honest Significant Difference method (p < 0.05). According to the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, genes that showed different RNA editing levels mainly participated in pathways highly related to mammary gland development, including MAPK, PI3K-Akt, FoxO, and GnRH signaling pathways. Collectively, this work demonstrated for the first time the dynamic RNA editome profiles in the mammary gland of yaks and shed more light on the mechanism that regulates lactation together with mammary gland development.
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Affiliation(s)
- Xiaoyun Wu
- Key Laboratory of Yak Breeding Engineering, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou 730050, China; (X.W.); (W.A.); (M.C.); (J.P.); (C.L.); (P.B.)
| | - Wondossen Ayalew
- Key Laboratory of Yak Breeding Engineering, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou 730050, China; (X.W.); (W.A.); (M.C.); (J.P.); (C.L.); (P.B.)
- Department of Animal Production and Technology, Wolkite University, Wolkite P.O. Box 07, Ethiopia
| | - Min Chu
- Key Laboratory of Yak Breeding Engineering, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou 730050, China; (X.W.); (W.A.); (M.C.); (J.P.); (C.L.); (P.B.)
| | - Jie Pei
- Key Laboratory of Yak Breeding Engineering, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou 730050, China; (X.W.); (W.A.); (M.C.); (J.P.); (C.L.); (P.B.)
| | - Chunnian Liang
- Key Laboratory of Yak Breeding Engineering, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou 730050, China; (X.W.); (W.A.); (M.C.); (J.P.); (C.L.); (P.B.)
| | - Pengjia Bao
- Key Laboratory of Yak Breeding Engineering, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou 730050, China; (X.W.); (W.A.); (M.C.); (J.P.); (C.L.); (P.B.)
| | - Xian Guo
- Key Laboratory of Yak Breeding Engineering, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou 730050, China; (X.W.); (W.A.); (M.C.); (J.P.); (C.L.); (P.B.)
- Correspondence: (X.G.); (P.Y.)
| | - Ping Yan
- Key Laboratory of Yak Breeding Engineering, Lanzhou Institute of Husbandry and Pharmaceutical Sciences, Chinese Academy of Agricultural Sciences, Lanzhou 730050, China; (X.W.); (W.A.); (M.C.); (J.P.); (C.L.); (P.B.)
- Correspondence: (X.G.); (P.Y.)
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12
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Abstract
Fluid secretion by exocrine glandular organs is essential to the survival of mammals. Each glandular unit within the body is uniquely organized to carry out its own specific functions, with failure to establish these specialized structures resulting in impaired organ function. Here, we review glandular organs in terms of shared and divergent architecture. We first describe the structural organization of the diverse glandular secretory units (the end-pieces) and their fluid transporting systems (the ducts) within the mammalian system, focusing on how tissue architecture corresponds to functional output. We then highlight how defects in development of end-piece and ductal architecture impacts secretory function. Finally, we discuss how knowledge of exocrine gland structure-function relationships can be applied to the development of new diagnostics, regenerative approaches and tissue regeneration.
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Affiliation(s)
- Sameed Khan
- Department of Obstetrics Gynecology and Reproductive Biology, Michigan State University, East Lansing, MI 48824, USA
- Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, MI 48824, USA
| | - Sarah Fitch
- Department of Obstetrics Gynecology and Reproductive Biology, Michigan State University, East Lansing, MI 48824, USA
- Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, MI 48824, USA
| | - Sarah Knox
- Department of Cell and Tissue Biology, University of California, San Francisco, CA 94143, USA
| | - Ripla Arora
- Department of Obstetrics Gynecology and Reproductive Biology, Michigan State University, East Lansing, MI 48824, USA
- Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, MI 48824, USA
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13
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Ling Y, Du Q. FGF10/FGF17 as prognostic and drug response markers in acute myeloid leukemia. Curr Res Transl Med 2021; 70:103316. [PMID: 34731724 DOI: 10.1016/j.retram.2021.103316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 09/21/2021] [Accepted: 10/08/2021] [Indexed: 11/16/2022]
Abstract
BACKGROUND Fibroblast growth factors (FGFs) play important roles in solid tumor progression. Little is known about the function and the prognostic value of distinct FGFs in acute myeloid leukemia (AML). METHODS We used dataset from Beat AML to screen the FGFs family in AML by log-rank test. Subsequently, we identified the biological functions and the crucial signaling pathways associated with these screened FGFs using gene set enrichment analysis (GSEA). In addition, IC50 from 122 small-molecule inhibitors was used to explore the relationship between these signaling pathways and targets of sensitive inhibitors. RESULTS Among the FGFs family, over expressions of FGF10/FGF17 were found to be significantly associated with poor prognosis. FGF10 over expression was related to FLT3 and NPM1 mutations, and FGF17 over expression was linked to MUC12 and ZRSR2 mutations. Some cancer-related pathways such as PI3K-Akt, MAPK were significantly enriched by GSEA, and these pathways were concordant with sensitive inhibitors targeted pathways. CONCLUSION Our results indicated that FGF10 and FGF17 could be prognostic biomarkers for survivals of AML patients, and potential therapeutic targets for small-molecule inhibitors.
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Affiliation(s)
- Yanying Ling
- Department of Laboratory Medicine, Guangzhou First People's Hospital, School of Medicine, South China University of Technology, Guangzhou, 510180, People's Republic of China
| | - Qinghua Du
- Department of Hematology, Guangzhou First People's Hospital, School of Medicine, South China University of Technology, Guangzhou, 510180, People's Republic of China.
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14
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Spina E, Cowin P. Embryonic mammary gland development. Semin Cell Dev Biol 2021; 114:83-92. [DOI: 10.1016/j.semcdb.2020.12.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Revised: 12/03/2020] [Accepted: 12/29/2020] [Indexed: 12/27/2022]
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15
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Marega M, Chen C, Bellusci S. Cross-Talk Between Inflammation and Fibroblast Growth Factor 10 During Organogenesis and Pathogenesis: Lessons Learnt From the Lung and Other Organs. Front Cell Dev Biol 2021; 9:656883. [PMID: 34136479 PMCID: PMC8201783 DOI: 10.3389/fcell.2021.656883] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 04/19/2021] [Indexed: 11/21/2022] Open
Abstract
The adult human lung is constantly exposed to irritants like particulate matter, toxic chemical compounds, and biological agents (bacteria and viruses) present in the external environment. During breathing, these irritants travel through the bronchi and bronchioles to reach the deeper lung containing the alveoli, which constitute the minimal functional respiratory units. The local biological responses in the alveoli that follow introduction of irritants need to be tightly controlled in order to prevent a massive inflammatory response leading to loss of respiratory function. Cells, cytokines, chemokines and growth factors intervene collectively to re-establish tissue homeostasis, fight the aggression and replace the apoptotic/necrotic cells with healthy cells through proliferation and/or differentiation. Among the important growth factors at play during inflammation, members of the fibroblast growth factor (Fgf) family regulate the repair process. Fgf10 is known to be a key factor for organ morphogenesis and disease. Inflammation is influenced by Fgf10 but can also impact Fgf10 expression per se. Unfortunately, the connection between Fgf10 and inflammation in organogenesis and disease remains unclear. The aim of this review is to highlight the reported players between Fgf10 and inflammation with a focus on the lung and to propose new avenues of research.
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Affiliation(s)
- Manuela Marega
- Key Laboratory of Interventional Pulmonology of Zhejiang Province, Department of Pulmonary and Critical Care Medicine, First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.,Member of the German Center for Lung Research (DZL), Department of Pulmonary and Critical Care Medicine and Infectious Diseases, Cardio-Pulmonary Institute (CPI), Universities of Giessen and Marburg Lung Center (UGMLC), Justus Liebig University Giessen, Giessen, Germany
| | - Chengshui Chen
- Key Laboratory of Interventional Pulmonology of Zhejiang Province, Department of Pulmonary and Critical Care Medicine, First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Saverio Bellusci
- Key Laboratory of Interventional Pulmonology of Zhejiang Province, Department of Pulmonary and Critical Care Medicine, First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.,Member of the German Center for Lung Research (DZL), Department of Pulmonary and Critical Care Medicine and Infectious Diseases, Cardio-Pulmonary Institute (CPI), Universities of Giessen and Marburg Lung Center (UGMLC), Justus Liebig University Giessen, Giessen, Germany
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16
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Epstein RJ, Tian LJ, Gu YF. 2b or Not 2b: How Opposing FGF Receptor Splice Variants Are Blocking Progress in Precision Oncology. JOURNAL OF ONCOLOGY 2021; 2021:9955456. [PMID: 34007277 PMCID: PMC8110382 DOI: 10.1155/2021/9955456] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 04/21/2021] [Indexed: 01/16/2023]
Abstract
More than ten thousand peer-reviewed studies have assessed the role of fibroblast growth factors (FGFs) and their receptors (FGFRs) in cancer, but few patients have yet benefited from drugs targeting this molecular family. Strategizing how best to use FGFR-targeted drugs is complicated by multiple variables, including RNA splicing events that alter the affinity of ligands for FGFRs and hence change the outcomes of stromal-epithelial interactions. The effects of splicing are most relevant to FGFR2; expression of the FGFR2b splice isoform can restore apoptotic sensitivity to cancer cells, whereas switching to FGFR2c may drive tumor progression by triggering epithelial-mesenchymal transition. The differentiating and regulatory actions of wild-type FGFR2b contrast with the proliferative actions of FGFR1 and FGFR3, and may be converted to mitogenicity either by splice switching or by silencing of tumor suppressor genes such as CDH1 or PTEN. Exclusive use of small-molecule pan-FGFR inhibitors may thus cause nonselective blockade of FGFR2 isoforms with opposing actions, undermining the rationale of FGFR2 drug targeting. This splice-dependent ability of FGFR2 to switch between tumor-suppressing and -driving functions highlights an unmet oncologic need for isoform-specific drug targeting, e.g., by antibody inhibition of ligand-FGFR2c binding, as well as for more nuanced molecular pathology prediction of FGFR2 actions in different stromal-tumor contexts.
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Affiliation(s)
- Richard J. Epstein
- New Hope Cancer Center, Beijing United Hospital, 9-11 Jiangtai West Rd, Chaoyang, Beijing 100015, China
- Garvan Institute of Medical Research and UNSW Clinical School, 84 Victoria St, Darlinghurst 2010 Sydney, Australia
| | - Li Jun Tian
- New Hope Cancer Center, Beijing United Hospital, 9-11 Jiangtai West Rd, Chaoyang, Beijing 100015, China
| | - Yan Fei Gu
- New Hope Cancer Center, Beijing United Hospital, 9-11 Jiangtai West Rd, Chaoyang, Beijing 100015, China
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17
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Vitale G, Cozzolino A, Malandrino P, Minotta R, Puliani G, Saronni D, Faggiano A, Colao A. Role of FGF System in Neuroendocrine Neoplasms: Potential Therapeutic Applications. Front Endocrinol (Lausanne) 2021; 12:665631. [PMID: 33935975 PMCID: PMC8080021 DOI: 10.3389/fendo.2021.665631] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 03/22/2021] [Indexed: 12/16/2022] Open
Abstract
Neuroendocrine neoplasms (NENs) are a heterogeneous group of tumors originating from neuroendocrine cells dispersed in different organs. Receptor tyrosine kinases are a subclass of tyrosine kinases with a relevant role in several cellular processes including proliferation, differentiation, motility and metabolism. Dysregulation of these receptors is involved in neoplastic development and progression for several tumors, including NENs. In this review, we provide an overview concerning the role of the fibroblast growth factor (FGF)/fibroblast growth factor receptor (FGFR) system in the development and progression of NENs, the occurrence of fibrotic complications and the onset of drug-resistance. Although no specific FGFR kinase inhibitors have been evaluated in NENs, several clinical trials on multitarget tyrosine kinase inhibitors, acting also on FGF system, showed promising anti-tumor activity with an acceptable and manageable safety profile in patients with advanced NENs. Future studies will need to confirm these issues, particularly with the development of new tyrosine kinase inhibitors highly selective for FGFR.
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Affiliation(s)
- Giovanni Vitale
- Laboratory of Geriatric and Oncologic Neuroendocrinology Research, Istituto Auxologico Italiano, IRCCS, Cusano Milanino, Italy
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Alessia Cozzolino
- Department of Experimental Medicine, Sapienza University of Rome, Rome, Italy
| | - Pasqualino Malandrino
- Endocrinology, Department of Clinical and Experimental Medicine, Garibaldi-Nesima Medical Center, University of Catania, Catania, Italy
| | - Roberto Minotta
- Department of Clinical Medicine and Surgery, Federico II University of Naples, Naples, Italy
| | - Giulia Puliani
- Department of Experimental Medicine, Sapienza University of Rome, Rome, Italy
- Oncological Endocrinology Unit, IRCCS Regina Elena National Cancer Institute, Rome, Italy
| | - Davide Saronni
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Antongiulio Faggiano
- Department of Clinical and Molecular Medicine, Sapienza University of Rome, Rome, Italy
| | - Annamaria Colao
- Department of Clinical Medicine and Surgery, Federico II University of Naples, Naples, Italy
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18
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Lin MJ, Lu CPJ. Glandular stem cells in the skin during development, homeostasis, wound repair and regeneration. Exp Dermatol 2021; 30:598-604. [PMID: 33686662 DOI: 10.1111/exd.14319] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 03/02/2021] [Accepted: 03/02/2021] [Indexed: 02/06/2023]
Abstract
Glands in the skin are essential for various physiological functions involving exocrine secretion. Like other tissues and organs, they possess the ability to repair injury and self-renew during homeostasis. Progenitor cells in glands are mostly unipotent but include some multipotent stem cells that function when extensive remodelling or regeneration is required. In this review, using two glandular models in skin, mouse sweat gland and mammary gland, we discuss lineage restriction that develops during glandular morphogenesis, as well as the mechanisms regulating cell fate and plasticity during wound repair and regeneration. Understanding the intrinsic and extrinsic factors that control the behaviours of glandular stem cell and maintain glandular functions will provide insight into future prospects for glandular regeneration.
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Affiliation(s)
- Meng-Ju Lin
- The Hansjörg Wyss Department of Plastic Surgery, New York University School of Medicine, New York, NY, USA
| | - Catherine Pei-Ju Lu
- The Hansjörg Wyss Department of Plastic Surgery, New York University School of Medicine, New York, NY, USA.,Department of Cell Biology, New York University School of Medicine, New York, NY, USA
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19
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Abstract
Wnt signaling is an important morphogenetic signaling pathway best known for its essential role in determining embryonic cell fates; it is often activated to re-specify fetal cells or to maintain the lineage flexibility of somatic stem cells. In this review, we consider the role of this pathway in the remarkable process of differentiation, growth and morphogenesis of the mammary gland during embryogenesis, ductal outgrowth and pregnancy. Specifically, mammary stem cells are compared with stem cells from other tissues, to identify commonalities and differences. Wnt signaling is known to be required to maintain the bipotent basal stem cell present in adult mammary ductal trees, however, the absence of this stem cell has little effect on growth or morphogenesis, and Wnt signaling is not induced during the ductal/alveolar expansion during pregnancy. The evidence for pre-determined hierarchies of mammary epithelial cells is reviewed, together with the role of signaling between mixtures of specified mammary epithelial cells in the maintenance of Wnt-dependent clonagenic stem cells. The dazzling variety of Wnt signaling components expressed by mammary epithelial cells is presented, along with some potential stromal sources of Wnt proteins that may be important starting points for the induction of plasticity in the epithelium.
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Affiliation(s)
- Caroline M Alexander
- McArdle Laboratory for Cancer Research, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, United States.
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