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1.
J Cell Mol Med ; 28(7): e18193, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38506205

RESUMO

Colorectal cancer (CRC) liver metastasis, albeit a stage-IV disease, is completely curable by surgical resection in selected patients. In addressing the molecular basics of this phenomenon, differentially expressed genes at primary and liver metastatic sites were screened by RNA sequencing with the use of paraffin-embedded surgical specimens. Chemokine C-C motif ligand 1 (CCL1), a chemotactic factor for a ligand of the chemokine C-C motif receptor 8 (CCR8), was isolated as one of the differentially expressed genes. Histological analysis revealed that the number of CCL1-positive cells, mainly tumour associated macrophages (TAMs) located in the stroma of CRC, decreased significantly at liver metastatic sites, while the expression level of CCR8 on CRC remained unchanged. To explore the biological significance of the CCL1-CCR8 axis in CRC, CCR8-positive CRC cell line Colo320DM was used to assess the effect of the CCL1-CCR8 axis on major signalling pathways, epithelial mesenchymal transition induction and cell motility. Upon stimulation of recombinant CCL1 (rCCL1), phosphorylation of AKT was observed in Colo320DM cells; on the other hand, the corresponding significant increase in MMP-2 levels demonstrated by RT-qPCR was nullified by siRNA (siCCR8). In the scratch test, rCCL1 treatment significantly increased the motility of Colo320DM cells, which was similarly nullified by siCCR8. Thus, the activation of the CCL1-CCR8 axis is a positive regulator of CRC tumour progression. Reduced CCL1 expression of TAMs at liver metastatic sites may partly explain the unique slow tumour progression of CRC, thus providing for a grace period for radical resection of metastatic lesions.


Assuntos
Neoplasias Colorretais , Fígado , Humanos , Quimiocina CCL1 , Ligantes , Fígado/metabolismo , Quimiocinas , Receptores de Quimiocinas/metabolismo , Neoplasias Colorretais/genética
2.
Histochem Cell Biol ; 160(5): 407-418, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37532885

RESUMO

The liver is known to possess remarkable regenerative potential, but persistent inflammation or severe acute injury can lead to liver fibrosis and incomplete regeneration, ultimately resulting in liver failure. Recent studies have shown that the axis of two types of CXCL12 receptors, CXCR4 and CXCR7, plays a crucial role in liver fibrosis and regeneration. The present study aimed to investigate the regulatory factors involved in CXCR4 expression in injured liver. Immunohistochemical screening of liver tissue samples collected during liver transplantation revealed a reciprocal expression pattern between CXCR4 and MeCP2. An in vitro system involving cultured cell lines and H2O2 treatment was established to study the impact of oxidative stress on signaling pathways and epigenetic alterations that affect CXCR4 mRNA expression. Operating through distinct signaling pathways, H2O2 treatment induced a dose-dependent increase in CXCR4 expression in both hepatocyte- and intrahepatic cholangiocyte-derived cells. Treatment of the cells with trichostatin and azacytidine modulated CXCR4 expression in hepatocytes by modifying the methylation status of CpG dinucleotides located in a pair of TA repeats adjacent to the TATA box of the CXCR4 gene promoter. Only MeCP2 bound to oligonucleotides representing the TATA box region when the cytosine residues within the sequence were methylated, as revealed by electrophoretic mobility shift assay (EMSA). Methylation-specific PCR analysis of microdissected samples revealed a correlation between the loss of CpG methylation and the upregulation of CXCR4 in injured hepatocytes, replicating the findings from the in vitro study. Besides the conventional MEK/ERK and NF-κB signaling pathways that activate CXCR4 in intrahepatic cholangiocytes, the unique epigenetic modifications observed in hepatocytes might also contribute to a shift in the CXCR4-CXCR7 balance towards CXCR4, leading to irreversible liver injury and fibrosis. This study highlights the importance of epigenetic modifications in regulating CXCR4 expression in liver injury and fibrosis.


Assuntos
Peróxido de Hidrogênio , Receptores CXCR4 , Humanos , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Hepatócitos/metabolismo , Cirrose Hepática , Regiões Promotoras Genéticas , Desmetilação , Expressão Gênica , Quimiocina CXCL12/genética , Quimiocina CXCL12/metabolismo , Quimiocina CXCL12/farmacologia
3.
Acta Histochem Cytochem ; 56(3): 41-47, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37425097

RESUMO

Keeping chromatin in a stable state is essential for genome stability, scheduled transcription, replication, DNA repair, and precise and reliable chromosome segregation and telomere maintenance during cell division. Over the past decade, research on chromatin remodeling has made great strides whereby modification of histone proteins is a key factor involved in many of the essential cellular processes. The nuclear findings of tumor cells that pathologists routinely examine are nothing but reflections of both genomic and histone alterations. Moreover, impaired histone function is known to be related to common diseases such as diabetes and atherosclerosis, and is, therefore, considered a potential therapeutic target. The present review first outlines the physiological function of histone proteins, and second, demonstrates their alterations to pathological states, emphasizing the importance of immunohistochemistry in histopathological diagnosis.

4.
Histochem Cell Biol ; 159(3): 263-273, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36418613

RESUMO

Since epigenetic modifications differ from cell to cell, detecting the DNA methylation status of individual cells is requisite. Therefore, it is important to conduct "morphology-based epigenetics research", in which the sequence-specific DNA methylation status is observed while maintaining tissue architecture. Here we demonstrate a novel histochemical technique that efficiently shows the presence of a single methylated cytosine in a sequence-dependent manner by applying ICON (interstrand complexation with osmium for nucleic acids) probes. By optimizing the concentration and duration of potassium osmate treatment, ICON probes selectively hybridize to methylated cytosine on tissue sections. Since the elongation process by rolling-circle amplification through the padlock probe and synchronous amplification by the hyperbranching reaction at a constant temperature efficiently amplifies the reaction, it is possible to specifically detect the presence of a single methylated cytosine. Since the ICON probe is cross-linked to the nuclear or mitochondrial DNA of the target cell, subsequent elongation and multiplication reactions proceed like a tree growing in soil with its roots firmly planted, thus facilitating the demonstration of methylated cytosine in situ. Using this novel ICON-mediated histochemical method, detection of the methylation of DNA in the regulatory region of the RANK gene in cultured cells and of mitochondrial DNA in paraffin sections of mouse cerebellar tissue was achievable. This combined ICON and rolling-circle amplification method is the first that shows evidence of the presence of a single methylated cytosine in a sequence-specific manner in paraffin sections, and is foreseen as applicable to a wide range of epigenetic studies.


Assuntos
Citosina , Parafina , Animais , Camundongos , Metilação de DNA , Epigênese Genética , DNA Mitocondrial
5.
Acta Histochem Cytochem ; 55(1): 1-7, 2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35444348

RESUMO

Over the past few decades, many researchers have individually identified tumor-related genes, and have accumulated information on their basic research in a database. With the development of technology that can comprehensively test the expression status within a short time, oncogene panel testing has become attainable. On the other hand, changes in gene expression that do not depend on changes in base sequences, that is, epigenetics, or more comprehensively, epigenomes, are also highly involved in the development and progression of disease. Oncogene panel tests tend to focus on DNA base mutations such as point mutations, deletions, duplications, and chimera formation. Elucidation leads to correct interpretation of diseases and treatment choices, and we are in an era where integrated understanding of the genome and epigenome is indispensable. In this review, we make every effort to cover a wide range of knowledge, including data on histone protein modification, non-coding (nc)RNA and DNA methylation, and recent application trials for demonstrating epigenetic alterations in histologic and cytologic specimens. We hope this review will help marshal the knowledge accumulated by researchers involved in genomic and epigenomic studies.

6.
Cell Tissue Res ; 388(1): 63-73, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35072792

RESUMO

Pericytes are pluripotent cells that enclose the endothelium of small blood vessels in the whole body. These cells are thought to play a limited role in vascular development and blood pressure regulation; however, current evidence from numerous studies suggests several significant biologic aspects of pericytes in animals. One viewpoint is that pericytes are also known as potential cellular origin of multiple soft tissue tumors. Experimental evidence of the cellular origin of pericytic tumors is still insufficient, however, and their molecular pathogenesis is poorly understood. Here, we used a conditional constitutively active Smoothened allele (Rosa-SmoM2) and Cre recombinase mice to activate hedgehog (Hh) signaling, exclusively in the monocyte/macrophage and osteoclast lineage (LysMcre) or in RANK expressing cells (RANKcre) that are recognized as osteoclast precursor cells. Mice conditionally expressing SmoM2 with LysMcre displayed no significant skeletal phenotype; surprisingly, however, RANKcre; Rosa-SmoM2 mice frequently developed progressive soft tissue tumors in regions of the leg. Genetic lineage tracing analysis uncovered a new domain of RANKcre-expressing cells in the skeletal muscle interstitial cells that display markers consistent with vascular pericytes. Neoplasms arising from these cells showed increased expression of Matrix metalloproteinases (MMPs) that are molecular indicators of malignancy. Moreover, the tumors displayed strong bone invasive potency associated with osteoclastic bone resorption. Thus, these findings provide a novel insight into tumor pathology: Hh signal activated-pericytes can be a potential cellular origin of multiple soft tissue tumors.


Assuntos
Pericitos , Neoplasias de Tecidos Moles , Animais , Modelos Animais de Doenças , Proteínas Hedgehog/metabolismo , Camundongos , Pericitos/metabolismo , Transdução de Sinais , Neoplasias de Tecidos Moles/patologia
7.
Bone ; 154: 116200, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34534711

RESUMO

Macrophages are progenitors of osteoclasts as well as regulators of bone metabolism. Macrophages mediate not only bone formation by osteoblasts under physiological conditions, but also bone regeneration after fracture. The mechanisms of macrophages regulation of bone formation and regeneration remain unclear, however. Here, we demonstrate that the liposome-encapsulated Clodronate (Clod-lip) injected mouse model with cortical bone defect induced by drill-hole injury and targeted depletion of phagocytic macrophages exhibits impaired angiogenesis of type H vessels that couple angiogenesis and osteogenesis. Moreover, we identify Tgfbi (encoding TGFBI), Plau (encoding uPA) and Tgfb1 (encoding TGF-ß1), through RNA-seq analysis, as genes of macrophage-secreted factors mediating angiogenesis and wound healing. The relevant mRNA was highly expressed in bone marrow-derived macrophages among bone cells, as determined through qRT-PCR. Finally, we disclose that treatment with uPA inhibitor or TGF-ß receptor I, receptor II inhibitor impairs bone regeneration after injury, confirming the importance of uPA and TGF-ß1 during bone regeneration. Our findings reveal a novel mechanism of bone regeneration mediated by macrophages.


Assuntos
Regeneração Óssea , Osteogênese , Animais , Macrófagos/metabolismo , Camundongos , Osteoblastos/metabolismo , Osteoclastos/metabolismo
8.
Biochem Biophys Res Commun ; 572: 86-91, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34358968

RESUMO

Receptor Activator of NF-κB (RANK) expressed on osteoclasts and their precursors is a receptor for RANK ligand (RANKL). Signals transduced by RANKL-RANK interaction induce genes essential for the differentiation and function of osteoclasts, partly through the direct binding of NFATc1, to target gene promoters. We have previously cloned a 6-kb fragment containing the 5'-flanking region of the mouse RANK gene and have demonstrated the presence of binding elements of hematological transcription factors, such as MITF, PU.1 and AP-1. Here, we demonstrated the presence of the functional NFATc1 responsive element on the RANK gene promoter. Transfection of an NFATc1-expression vector increased RANK mRNA that was subsequently nullified by NFATc1 knockdown. With the use of electrophoretic mobility shift assay (EMSA), an oligonucleotide (-388/-353) showed specific protein-DNA binding that was blockshifted with an anti-NFATc1 antibody and washed out with excess amounts of the cold consensus sequence. Co-transfection studies with the use of an NFATc1-expression vector and RANK promoter-reporter constructs showed that NFATc1 increased promoter activity 2-fold in RAW264.7 cells that was again nullified as disclosed by mutagenesis studies. Taken together, these results indicate that RANK transcription is positively regulated by the RANKL signal through the direct binding of NFATc1 to its specific binding site of the RANK gene promoter, and suggest the presence of a crucial positive feedback mechanism of gene expression that promotes accelerated terminal differentiation of RANK-positive committed precursors to mature osteoclasts.


Assuntos
Fatores de Transcrição NFATC/metabolismo , Regiões Promotoras Genéticas/genética , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Animais , Células Cultivadas , Retroalimentação Fisiológica , Camundongos , Camundongos Endogâmicos , Fatores de Transcrição NFATC/genética , Receptor Ativador de Fator Nuclear kappa-B/genética , Transdução de Sinais/genética
9.
Int J Mol Sci ; 22(3)2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33530552

RESUMO

The reproductive tract in mammals emerges from two ductal systems during embryogenesis: Wolffian ducts (WDs) and Mullerian ducts (MDs). Most of the female reproductive tract (FRT) including the oviducts, uterine horn and cervix, originate from MDs. It is widely accepted that the formation of MDs depends on the preformed WDs within the urogenital primordia. Here, we found that the WD mesenchyme under the regulation of Hedgehog (Hh) signaling is closely related to the developmental processes of the FRT during embryonic and postnatal periods. Deficiency of Sonic hedgehog (Shh), the only Hh ligand expressed exclusively in WDs, prevents the MD mesenchyme from affecting uterine growth along the radial axis. The in vivo cell tracking approach revealed that after WD regression, distinct cells responding to WD-derived Hh signal continue to exist in the developing FRT and gradually contribute to the formation of various tissues such as smooth muscle, endometrial stroma and vascular vessel, in the mouse uterus. Our study thus provides a novel developmental mechanism of FRT relying on WD.


Assuntos
Genitália Feminina/embriologia , Genitália Feminina/metabolismo , Proteínas Hedgehog/metabolismo , Organogênese , Transdução de Sinais , Útero/embriologia , Útero/metabolismo , Animais , Biomarcadores , Diferenciação Celular , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Modelos Biológicos , Ductos Paramesonéfricos/embriologia , Ductos Paramesonéfricos/metabolismo , Organogênese/genética
10.
Biochem Biophys Res Commun ; 529(2): 186-190, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32703409

RESUMO

The long bone midshaft expands by forming primary osteons at the periosteal surface of cortical bone in humans and rodents. Osteoblastic bone formation in the vascular cavity in the center of primary osteons is delayed during cortical bone development. The mechanisms of the formation of primary osteons is not fully understood, however. Focusing on NOTCH1 signaling, an inhibitory signaling on osteoblastic bone formation, our immunohistochemical analysis revealed Delta like1 (DLL1), a ligand of NOTCH1, and the NOTCH1 intracellular domain (NICD, an activated form of NOTCH1) immunoreactivity, in the cuboidal osteoblasts lining the bone surface in the vascular cavity of primary osteons during postnatal growth in rats. Interestingly, five days after treatment of primary osteoblasts with ascorbic acid and ß glycerophosphate, protein levels of both DLL1 and NICD increased transiently, indicating that DLL1 activates NOTCH1 in primary cultured osteoblasts. Thus, the results imply that DLL1-NOTCH1 signaling in osteoblasts is associated with primary osteonal bone formation.


Assuntos
Osso Cortical/citologia , Peptídeos e Proteínas de Sinalização Intercelular/análise , Proteínas de Membrana/análise , Osteoblastos/citologia , Receptor Notch1/análise , Animais , Células Cultivadas , Osso Cortical/metabolismo , Masculino , Osteoblastos/metabolismo , Domínios Proteicos , Ratos , Ratos Wistar
11.
Acta Histochem Cytochem ; 53(2): 21-31, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32410750

RESUMO

Diabetic nephropathy is a major source of end-stage renal failure, affecting about one-third cases of diabetes mellitus. It has long been accepted that diabetic nephropathy is mainly characterized by glomerular defects, while clinical observations have implied that renal tubular damage is closely linked to kidney dysfunction at the early stages of diabetic nephropathy. In this study, we conducted pathohistological analyses focusing on renal tubular lesions in the early-stage diabetic kidney with the use of a streptozotocin (STZ)-induced diabetes mellitus mouse model. The results revealed that histological alterations in renal tubules, shown by a vacuolar nucleic structure, accumulations of PAS-positive substance, and accelerated restoration stress, occur initially without the presence of glomerular lesions in the early-stage diabetic kidney, and that these tubular defects are localized mainly in proximal renal tubules. Moreover, enhanced expression of RAGE, suggesting an aberrant activation of AGEs-RAGE signaling pathway, and accumulation of oxidative modified mitochondria through the impaired autophagy/lysosome system, were also seen in the damaged diabetic proximal renal tubules. Our findings indicate that proximal tubular defects are the initial pathological events increasingly linked to the progression of diabetic nephropathy, and that controlling renal tubular damage could be an effective therapeutic strategy for the clinical treatment of diabetic nephropathy.

12.
Int J Mol Sci ; 21(8)2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32326611

RESUMO

The functional role of the Hedgehog (Hh)-signaling pathway has been widely investigated in bone physiology/development. Previous studies have, however, focused primarily on Hh functions in bone formation, while its roles in bone resorption have not been fully elucidated. Here, we found that cyclopamine (smoothened (Smo) inhibitor), GANT-58 (GLI1 inhibitor), or GANT-61 (GLI1/2 inhibitor) significantly inhibited RANKL-induced osteoclast differentiation of bone marrow-derived macrophages. Although the inhibitory effects were exerted by cyclopamine or GANT-61 treatment during 0-48 h (early stage of osteoclast differentiation) or 48-96 h (late stage of osteoclast differentiation) after RANKL stimulation, GANT-58 suppressed osteoclast formation only during the early stage. These results suggest that the Smo-GLI1/2 axis mediates the whole process of osteoclastogenesis and that GLI1 activation is requisite only during early cellular events of osteoclastogenesis. Additionally, macrophage/osteoclast-specific deletion of Smo in mice was found to attenuate the aging phenotype characterized by trabecular low bone mass, suggesting that blockage of the Hh-signaling pathway in the osteoclast lineage plays a protective role against age-related bone loss. Our findings reveal a specific role of the Hh-signaling pathway in bone resorption and highlight that its inhibitors show potential as therapeutic agents that block osteoclast formation in the treatment of senile osteoporosis.


Assuntos
Proteínas Hedgehog/antagonistas & inibidores , Proteínas Hedgehog/metabolismo , Macrófagos/metabolismo , Osteogênese/efeitos dos fármacos , Osteoporose/metabolismo , Transdução de Sinais/efeitos dos fármacos , Envelhecimento/efeitos dos fármacos , Envelhecimento/genética , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/genética , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteoporose/diagnóstico por imagem , Osteoporose/genética , Piridinas/farmacologia , Pirimidinas/farmacologia , Receptor de Fator Estimulador de Colônias de Macrófagos/genética , Receptor de Fator Estimulador de Colônias de Macrófagos/metabolismo , Receptor Smoothened/antagonistas & inibidores , Receptor Smoothened/metabolismo , Tiofenos/farmacologia , Regulação para Cima , Alcaloides de Veratrum/farmacologia , Microtomografia por Raio-X , Proteína GLI1 em Dedos de Zinco/antagonistas & inibidores , Proteína GLI1 em Dedos de Zinco/metabolismo , Proteína Gli2 com Dedos de Zinco/antagonistas & inibidores , Proteína Gli2 com Dedos de Zinco/metabolismo
13.
Biochem Biophys Res Commun ; 523(4): 961-965, 2020 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-31964526

RESUMO

Low density lipoprotein receptor-related protein 1 (LRP1), a multifunctional cell surface protein, is expressed in bone marrow-derived macrophages. While LRP1 is thought to be a suppressor of osteoclast differentiation at late stages, its function at early stages remains unclear. Here we demonstrate that Lrp1 stable knockdown by lentiviral short hairpin RNA in macrophage cell line RAW264 cells inhibited RANKL-induced osteoclast formation and osteoclastic master transcription factor Nfatc1 mRNA expression as assessed by quantitative RT-PCR. Furthermore, knockdown of the Lrp1 gene suppressed not only differentiation, but also proliferation, and inhibitory effects on osteoblastic ALP activity by osteoclast-derived humoral factors. Thus, we propose that LRP1 in macrophages is required for both differentiation into osteoclasts and osteoclast-osteoblast interactions.


Assuntos
Comunicação Celular , Diferenciação Celular , Técnicas de Silenciamento de Genes , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Osteoblastos/citologia , Osteoclastos/citologia , Osteoclastos/metabolismo , Animais , Proliferação de Células , Camundongos , Camundongos Endogâmicos C57BL , Células RAW 264.7
14.
Int J Mol Sci ; 21(1)2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31861793

RESUMO

Hedgehog (Hh) signaling is an essential growth factor signaling pathway especially in the regulation of epithelial-mesenchymal interactions (EMI) during the development of the urogenital organs such as the bladder and the external genitalia (EXG). The Hh ligands are often expressed in the epithelia, affecting the surrounding mesenchyme, and thus constituting a form of paracrine signaling. The development of the urogenital organ, therefore, provides an intriguing opportunity to study EMI and its relationship with other pathways, such as hormonal signaling. Cellular interactions of prostate cancer (PCa) with its neighboring tissue is also noteworthy. The local microenvironment, including the bone metastatic site, can release cellular signals which can affect the malignant tumors, and vice versa. Thus, it is necessary to compare possible similarities and divergences in Hh signaling functions and its interaction with other local growth factors, such as BMP (bone morphogenetic protein) between organogenesis and tumorigenesis. Additionally, this review will discuss two pertinent research aspects of Hh signaling: (1) the potential signaling crosstalk between Hh and androgen signaling; and (2) the effect of signaling between the epithelia and the mesenchyme on the status of the basement membrane with extracellular matrix structures located on the epithelial-mesenchymal interface.


Assuntos
Transição Epitelial-Mesenquimal , Proteínas Hedgehog/metabolismo , Neoplasias da Próstata/metabolismo , Androgênios/genética , Androgênios/metabolismo , Animais , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Comunicação Celular , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Masculino , Organogênese , Neoplasias da Próstata/genética , Mapas de Interação de Proteínas , Transdução de Sinais , Microambiente Tumoral
15.
Int J Mol Sci ; 20(23)2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31757091

RESUMO

The longitudinal growth of long bone, regulated by an epiphyseal cartilaginous component known as the "growth plate", is generated by epiphyseal chondrocytes. The growth plate provides a continuous supply of chondrocytes for endochondral ossification, a sequential bone replacement of cartilaginous tissue, and any failure in this process causes a wide range of skeletal disorders. Therefore, the cellular and molecular characteristics of the growth plate are of interest to many researchers. Hedgehog (Hh), well known as a mitogen and morphogen during development, is one of the best known regulatory signals in the developmental regulation of the growth plate. Numerous animal studies have revealed that signaling through the Hh pathway plays multiple roles in regulating the proliferation, differentiation, and maintenance of growth plate chondrocytes throughout the skeletal growth period. Furthermore, over the past few years, a growing body of evidence has emerged demonstrating that a limited number of growth plate chondrocytes transdifferentiate directly into the full osteogenic and multiple mesenchymal lineages during postnatal bone development and reside in the bone marrow until late adulthood. Current studies with the genetic fate mapping approach have shown that the commitment of growth plate chondrocytes into the skeletal lineage occurs under the influence of epiphyseal chondrocyte-derived Hh signals during endochondral bone formation. Here, we discuss the valuable observations on the role of the Hh signaling pathway in the growth plate based on mouse genetic studies, with some emphasis on recent advances.


Assuntos
Desenvolvimento Ósseo , Ossos da Extremidade Inferior/metabolismo , Ossos da Extremidade Superior/metabolismo , Lâmina de Crescimento/metabolismo , Proteínas Hedgehog/metabolismo , Animais , Ossos da Extremidade Inferior/crescimento & desenvolvimento , Ossos da Extremidade Superior/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Lâmina de Crescimento/crescimento & desenvolvimento , Proteínas Hedgehog/genética , Humanos , Transdução de Sinais
16.
Acta Histochem Cytochem ; 52(4): 77-83, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31592201

RESUMO

The interleukin (IL)-4, 1,25(OH)2D3 and retinoic acid, increase surface expression of functional integrin αvß3 on murine osteoclast precursors. All three agonists stimulate transcription of the ß3 gene, leading to increased steady-state levels of mRNA this protein. By contrast, mRNA levels of αv remain unchanged. In each instance, the increase in the surface expression of the integrin results in increased migration of the cells onto an αvß3 substrate. Because ß3 subunit, except platelet where ß3 subunit conform a dimer with αIIb, associates solely with αv subunit monogamously, while promiscuous αv subunit combines with various subunit, our present data support the idea that the ß3 subunit governs the surface-expressed functional integrin complex.

17.
Biochem Biophys Res Commun ; 515(2): 268-274, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31146918

RESUMO

Receptor activator of NF-κB (RANK) expressed on osteoclasts and their precursors is a receptor for RANK ligand (RANKL). Signals transduced by RANKL-RANK interaction induce genes essential for the differentiation and function of osteoclasts. We have cloned a basic promoter region of the mouse RANK gene and have analyzed the transcription machinery by transcription factors such as PU.1 (-480), and MITF (-100). Here, we examined the regulatory mechanisms of RANK gene transcription through AP-1 binding site, agagctca (-240). RANK mRNA expression in pre-osteoclastic RAW264.7 cells was induced by Phorbol12-myristate13-acetate (PMA) and suppressed by protein kinase C (PKC) inhibitor calphostin C. In RAW264.7 cells, Fos knockdown by siRNA blocked the inducible effect of PMA on RANK expression. By EMSA, an oligonucleotide (-246/-238) showed DNA protein binding, the specificity of which was confirmed by block-shift assay with an anti-Fos antibody and by the addition of the excess of a cold consensus probe. Co-transfection with a Fos expression vector showed that Fos increased RANK promoter activity 6-fold in RAW264.7 cells, and the addition of PU.1 and MITF superinduced the activity more than twenty-fold by the addition of PU.1 and MITF. Mutagenesis of the putative AP-1 site (-240) blocked the inducible effect of Fos on promoter activity. Taken together, these results indicate that during the differentiation of bone marrow mono-nucleated cells into osteoclast precursors, RANK transcription is positively regulated by Fos/AP-1 through the binding element of its gene promoter, supporting the concept that Fos activation by continuous CSF-1 stimulation on macrophages triggers initial expression of RANK and, later, a positive feedback loop by RANKL-RANK interaction.


Assuntos
Osteogênese/genética , Osteogênese/fisiologia , Proteína Quinase C/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/genética , Animais , Sequência de Bases , Sítios de Ligação/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Ativação Enzimática , Técnicas de Silenciamento de Genes , Camundongos , Mutagênese Sítio-Dirigida , Osteoclastos/citologia , Osteoclastos/metabolismo , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-fos/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-fos/genética , Ligante RANK/metabolismo , Células RAW 264.7 , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , Elementos de Resposta , Fator de Transcrição AP-1/metabolismo , Ativação Transcricional
18.
Histochem Cell Biol ; 150(1): 3-12, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29721644

RESUMO

Cytosine methylation plays a major role in the regulation of sequential and tissue-specific expression of genes. De novo aberrant DNA methylation and demethylation are also crucial processes in tumorigenesis and tumor progression. The mechanisms of how and when such aberrant methylation and demethylation occur in tumor cells are still obscure, however. To evaluate subtle epigenetic alteration among minor subclonal populations, morphology-oriented epigenetic analysis is requisite, especially where heterogeneity and flexibility are as notable as in the process of cancer progression and cellular differentiation at critical stages. Therefore, establishment of reliable morphology-oriented epigenetic studies has become increasingly important in not only the experimental but also the diagnostic field. By selecting a subset of cells based on characteristic morphological features disclosed by microdissection or in situ hybridization, we discovered how methylation at certain CpG sites outside of CpG islands would play a crucial epigenetic role in the versatility and flexibility of gene expression during cancer progression. In this review, we first introduce technical aspects of two morphology-oriented epigenetic studies: (1) histoendonuclease-linked detection of methylated sites of DNA (HELMET), and (2) padlock probe and rolling circle amplification (RCA) for in situ identification of methylated cytosine in a sequence-dependent manner. We then present our observation of a novel MeCP2-mediated gene-silencing mechanism through the addition of methylation to a single-CpG-locus upstream of the TATA-box of the receptor activator of NF-κB ligand (RANKL) and of secreted frizzled-related protein 4 (SFRP4) gene promoters.


Assuntos
Epigênese Genética/genética , Neoplasias/genética , Ilhas de CpG/genética , Citosina/metabolismo , Metilação de DNA , Inativação Gênica , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Ligante RANK/genética , Ligante RANK/metabolismo
19.
Nat Rev Urol ; 15(6): 358-368, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29670181

RESUMO

The biology of masculinization is fundamentally important for understanding the embryonic developmental processes that are involved in the development of the male reproductive tract, external genitalia, and also the tumorigenesis of prostate cancer. The molecular mechanisms of masculinization are of interest to many researchers and clinicians involved in varied fields, including molecular developmental biology, cancer research, endocrinology, and urology. Androgen signalling is mediated by the nuclear androgen receptor, which has fundamental roles in masculinization during development. Various modes of androgen signalling, including 5α-dihydrotestosterone-induced regulation of mesenchymal cell proliferation, have been observed in masculinization. Such regulation is essential for regulating urogenital tissue development, including external genitalia development. Androgen-induced genes, such as MAFB, which belongs to the activator protein 1 (AP-1) superfamily of genes, have essential roles in male urethral formation, and disruption of its signalling can interfere with urethral formation, which often results in hypospadias. Another AP-1 superfamily gene, ATF3, could be responsible for some instances of hypospadias in humans. These androgen-dependent signals and downstream events are crucial for not only developmental processes but also processes of diseases such as hypospadias and prostate cancer.


Assuntos
Androgênios/metabolismo , Genitália Masculina/embriologia , Receptores Androgênicos/metabolismo , Diferenciação Sexual/fisiologia , Biomarcadores/metabolismo , Genitália Masculina/anormalidades , Genitália Masculina/metabolismo , Humanos , Hipospadia/embriologia , Hipospadia/metabolismo , Masculino , Neoplasias da Próstata/etiologia , Neoplasias da Próstata/metabolismo , Transdução de Sinais
20.
Diagn Pathol ; 13(1): 1, 2018 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-29368652

RESUMO

BACKGROUND: A proper balance between the activator and the repressor form of GLI3, a zinc-finger transcription factor downstream of hedgehog signaling, is essential for proper development of various organs during development. Mutations in different domains of the GLI3 gene underlie several congenital diseases including Greig cephalopolysyndactyly syndrome (GCPS) and Pallister-Hall syndrome (PHS). CASE PRESENTATION: Here, we describe the case of an overlapped phenotype of these syndromes with agenesis of the gallbladder and the pancreas, bearing a c.2155 C > T novel likely pathogenic variant of GLI3 gene by missense point mutation causing p.P719S at the proteolytic cleavage site. CONCLUSIONS: Although agenesis of the gallbladder and the pancreas is uncommon in GLI3 morphopathy, a slight difference in the gradient or the balance between activator and repressor in this case may hinder sophisticated spatial and sequential hedgehog signaling that is essential for proper development of gallbladder and pancreas from endodermal buds.


Assuntos
Acrocefalossindactilia/genética , Vesícula Biliar/anormalidades , Proteínas do Tecido Nervoso/genética , Síndrome de Pallister-Hall/genética , Pâncreas/anormalidades , Proteína Gli3 com Dedos de Zinco/genética , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/patologia , Acrocefalossindactilia/patologia , Feto , Humanos , Masculino , Mutação de Sentido Incorreto , Síndrome de Pallister-Hall/patologia , Fenótipo , Mutação Puntual
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