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1.
Nature ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38768632

RESUMO

Epigenetic reprogramming resets parental epigenetic memories and differentiates primordial germ cells (PGCs) into mitotic pro-spermatogonia or oogonia, ensuring sexually dimorphic germ-cell development for totipotency 1. In vitro reconstitution of epigenetic reprogramming in humans remains a fundamental challenge. Here, we establish a robust strategy for inducing epigenetic reprogramming and differentiation of pluripotent stem cell (PSC)-derived human PGC-like cells (hPGCLCs) into mitotic pro-spermatogonia or oogonia, coupled with their extensive amplification (~>1010-fold). Strikingly, bone morphogenetic protein (BMP) signalling is a key driver of these processes: BMP-driven hPGCLC differentiation involves an attenuation of the mitogen-activated protein kinase/extracellular-regulated kinase (MAPK/ERK) pathway and both de novo and maintenance DNA methyltransferase (DNMT) activities, likely promoting replication-coupled, passive DNA demethylation. On the other hand, hPGCLCs deficient in tens-eleven translocation (TET) 1, an active DNA demethylase abundant in human germ cells 2,3, differentiate into extraembryonic cells, including amnion, with de-repression of key genes bearing bivalent promoters; these cells fail to fully activate genes vital for spermatogenesis and oogenesis, with their promoters remaining methylated. Our study elucidates the framework of epigenetic reprogramming in humans, making a fundamental advance in human biology, and through the generation of abundant mitotic pro-spermatogonia and oogonia-like cells, represents a milestone for human in vitro gametogenesis (IVG) research and its potential translation into reproductive medicine.

2.
Oncol Rep ; 47(4)2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35088890

RESUMO

The phosphatidylinositol 3­kinase/mammalian target of rapamycin (PI3K/mTOR) signaling pathway is a therapeutic target for various types of human tumors, and dual PI3K/mTOR inhibitors demonstrate antitumor activities in both preclinical and clinical studies. However, resistance mechanisms limit their abilities. As the molecular mechanisms involved in the cellular resistance are not clear in any canine tumors, an understanding of resistance mechanisms would support the potential use of dual PI3K/mTOR inhibitors in canine tumors. The antitumor activity of gedatolisib on cell viability, protein phosphorylation, and cell cycle distribution was assessed using 12 canine tumor cell lines from 6 types of tumors. In addition, the molecular determinants involved in the cellular sensitivity to gedatolisib were explored by investigating the involvement of serum­and­glucocorticoid­induced kinase 1 (SGK1), PIK3CA, and ATP­binding cassette, subfamily B, member 1 (ABCB1). The results demonstrated that gedatolisib decreased cell viability in all cell lines, with IC50 values <1 µM in 10 of the 12 lines. Gedatolisib inhibited Akt and mTOR complex 1 substrate phosphorylation and induced G0/G1 cell cycle arrest. However, certain cell lines with higher IC50 values were more resistant to these effects. These cell lines exhibited higher ABCB1 activity and the ABCB1 inhibitor cyclosporin A enhanced the decrease of cell viability caused by gedatolisib. SGK1 overexpression did not confer resistance to gedatolisib. The mutations of E545K and H1047R in PIK3CA were not observed. The present results indicated that gedatolisib decreased cell viability in canine tumor cell lines and ABCB1 played an important role in gedatolisib resistance, supporting the potential use of gedatolisib for canine tumors.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Morfolinas/farmacologia , Neoplasias/tratamento farmacológico , Fosfatidilinositol 3-Quinases/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Triazinas/farmacologia , Animais , Cães , Inibidores de Proteínas Quinases/farmacologia
3.
Vet Comp Oncol ; 20(1): 324-335, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34719098

RESUMO

Cancer stem-like cells (CSCs) cause treatment failure in various tumours; however, establishing CSC-targeted therapies has been hampered by difficulties in the identification and isolation of this small sub-population of cells. Recent studies have revealed that tumour cells with low proteasome activity display a CSC phenotype that can be utilized to image CSCs in canines. This study visualizes and reveals the CSC-like properties of tumour cells with low proteasome activity in HMPOS (osteosarcoma) and MegTCC (transitional cell carcinoma), which are canine cell lines. The parent cells were genetically engineered to express ZsGreen1, a fluorescent protein connected to the carboxyl-terminal degron of canine ornithine decarboxylase that accumulates with low proteasome activity (ZsG+ cells). ZsG+ cells were imaged and the mode of action of this system was confirmed using a proteasome inhibitor (MG-132), which increased the ZsGreen1 fluorescence intensity. The CSC-like properties of ZsG+ cells were evaluated on the basis of cell divisions, cell cycle, the expression of CSC markers and tumourigenicity. ZsG+ cells underwent asymmetric divisions and had a low percentage of G0/G1 phase cells; moreover, ZsG+ cells expressed CSC markers such as CD133 and showed a large tumourigenic capability. In histopathological analysis, ZsG+ cells were widely distributed in the tumour samples derived from ZsG+ cells and in the proliferative regions of the tumours. The results of this study indicate that visualized canine tumour cells with low proteasome activity have a CSC-like phenotype and that this visualization system can be utilized to identify and isolate canine CSCs.


Assuntos
Neoplasias Ósseas , Doenças do Cão , Osteossarcoma , Animais , Neoplasias Ósseas/patologia , Neoplasias Ósseas/veterinária , Linhagem Celular Tumoral , Doenças do Cão/patologia , Cães , Células-Tronco Neoplásicas/patologia , Osteossarcoma/patologia , Osteossarcoma/veterinária , Complexo de Endopeptidases do Proteassoma/metabolismo
4.
Cell Rep ; 37(5): 109909, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34731633

RESUMO

Human induced pluripotent stem cells (hiPSCs) show variable differentiation potential due to their epigenomic heterogeneity, whose extent/attributes remain unclear, except for well-studied elements/chromosomes such as imprints and the X chromosomes. Here, we show that seven hiPSC lines with variable germline potential exhibit substantial epigenomic heterogeneity, despite their uniform transcriptomes. Nearly a quarter of autosomal regions bear potentially differential chromatin modifications, with promoters/CpG islands for H3K27me3/H2AK119ub1 and evolutionarily young retrotransposons for H3K4me3. We identify 145 large autosomal blocks (≥100 kb) with differential H3K9me3 enrichment, many of which are lamina-associated domains (LADs) in somatic but not in embryonic stem cells. A majority of these epigenomic heterogeneities are independent of genetic variations. We identify an X chromosome state with chromosome-wide H3K9me3 that stably prevents X chromosome erosion. Importantly, the germline potential of female hiPSCs correlates with X chromosome inactivation. We propose that inherent genomic properties, including CpG density, transposons, and LADs, engender epigenomic heterogeneity in hiPSCs.


Assuntos
Cromossomos Humanos X , Epigênese Genética , Epigenoma , Heterogeneidade Genética , Histonas/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Inativação do Cromossomo X , Diferenciação Celular , Linhagem Celular , Montagem e Desmontagem da Cromatina , Ilhas de CpG , Elementos de DNA Transponíveis , Epigenômica , Evolução Molecular , Humanos , Metilação , Lâmina Nuclear/genética , Lâmina Nuclear/metabolismo , Processamento de Proteína Pós-Traducional , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
5.
Cell Stem Cell ; 28(12): 2167-2179.e9, 2021 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-34496297

RESUMO

Mammalian male germ-cell development consists of three distinct phases: primordial germ cell (PGC) development, male germ-cell specification for spermatogonium development, and ensuing spermatogenesis. Here, we show an in vitro reconstitution of whole male germ-cell development by pluripotent stem cells (PSCs). Mouse embryonic stem cells (mESCs) are induced into PGC-like cells (mPGCLCs), which are expanded for epigenetic reprogramming. In reconstituted testes under an optimized condition, such mPGCLCs differentiate into spermatogonium-like cells with proper developmental transitions, gene expression, and cell-cycle dynamics and are expanded robustly as germline stem cell-like cells (GSCLCs) with an appropriate androgenetic epigenome. Importantly, GSCLCs show vigorous spermatogenesis, not only upon transplantation into testes in vivo but also under an in vitro culture of testis transplants, and the resultant spermatids contribute to fertile offspring. By uniting faithful recapitulations of the three phases of male germ-cell development, our study creates a paradigm for the in vitro male gametogenesis by PSCs.


Assuntos
Células-Tronco Pluripotentes , Animais , Diferenciação Celular , Epigenômica , Células Germinativas , Masculino , Camundongos , Espermatogênese , Espermatogônias
6.
Mol Ther Oncolytics ; 22: 143-151, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34514095

RESUMO

Metformin has many anti-cancer effects, alone or in combination with radiation. However, the mechanism underlying its radio-sensitized effect is still unclear, especially for cancer stem-like cells (CSCs). Here, the radio-sensitized effect of metformin was investigated, and its mechanism was revealed in CSCs derived from canine osteosarcoma cell line (HMPOS), a canine osteosarcoma cell line. Spheroid cells (SCs) were used as CSCs-rich cells derived from sphere formation, and SCs were compared with normal adherent culture cells (ACs). The radio-sensitizing effect of metformin using clonogenic assay and tumor growth in mice xenograft model were evaluated, and the mechanism of its radio-sensitization focusing on mitochondrial function was revealed. Metformin significantly enhanced radio-sensitivity of SCs through its inhibition of the mitochondrial function, as shown by decreased oxygen consumption, decreased mitochondrial membrane potential, and decreased ATP production. Additionally, SCs had a higher ability of mitochondrial respiration than ACs, which may have caused difference of their sensitivity of metformin and irradiation. In conclusion, mitochondrial function might play an important role in the sensitivity of metformin and irradiation, and drugs that target mitochondrial respiration, such as metformin, are promising radio-sensitizers to target CSCs.

7.
Life Sci Alliance ; 4(5)2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33608411

RESUMO

The in vitro reconstitution of human germ-cell development provides a robust framework for clarifying key underlying mechanisms. Here, we explored transcription factors (TFs) that engender the germ-cell fate in their pluripotent precursors. Unexpectedly, SOX17, TFAP2C, and BLIMP1, which act under the BMP signaling and are indispensable for human primordial germ-cell-like cell (hPGCLC) specification, failed to induce hPGCLCs. In contrast, GATA3 or GATA2, immediate BMP effectors, combined with SOX17 and TFAP2C, generated hPGCLCs. GATA3/GATA2 knockouts dose-dependently impaired BMP-induced hPGCLC specification, whereas GATA3/GATA2 expression remained unaffected in SOX17, TFAP2C, or BLIMP1 knockouts. In cynomolgus monkeys, a key model for human development, GATA3, SOX17, and TFAP2C were co-expressed exclusively in early PGCs. Crucially, the TF-induced hPGCLCs acquired a hallmark of bona fide hPGCs to undergo epigenetic reprogramming and mature into oogonia/gonocytes in xenogeneic reconstituted ovaries. By uncovering a TF circuitry driving the germ line program, our study provides a paradigm for TF-based human gametogenesis.


Assuntos
Células Germinativas/metabolismo , Fatores de Transcrição SOXF/metabolismo , Fator de Transcrição AP-2/metabolismo , Animais , Diferenciação Celular/genética , Linhagem da Célula/genética , Feminino , Fatores de Transcrição GATA/genética , Fatores de Transcrição GATA/metabolismo , Células Germinativas/fisiologia , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Macaca fascicularis , Camundongos , Camundongos Endogâmicos ICR , Fatores de Transcrição SOXF/genética , Transdução de Sinais/genética , Fator de Transcrição AP-2/genética , Fatores de Transcrição/metabolismo
8.
Int J Surg Case Rep ; 78: 342-346, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33388515

RESUMO

INTRODUCTION: Intestinal malrotation is a congenital anatomical anomaly resulting from abnormal midgut rotation. Many cases occur during childhood and present with intestinal obstruction and midgut volvulus. Intestinal malrotation rarely occurs in adults and is found incidentally because it is asymptomatic. We herein report a case of intestinal malrotation, and colorectal cancer operated laparoscopically. PRESENTATION OF CASE: A 78-year-old man presented to our Department of Surgical Gastroenterology with fecal occult blood. There were no abnormal findings in the physical examination. Colonoscopy revealed a type 3 tumor in the cecum. Contrast-enhanced computed tomography revealed that the tumor was located in the appendix along the midline of the abdomen. The small intestine and colon occupied the right and left sides of the abdominal cavity, respectively. The diagnosis was appendiceal cancer with nonrotation-type intestinal malrotation. A laparoscopy-assisted ileocecal resection was performed. During surgery, the right-side colon was not fixed to the retroperitoneum, and the right-side colon could be extracted out of the abdominal cavity through the umbilical wound with only adhesive dissection, and mesenteric and lymph node dissection can be performed outside the body. The postoperative course was uneventful. DISCUSSION: Appendiceal cancer with intestinal malrotation is managed with laparoscopic surgery because this method is safe and minimally invasive. CONCLUSION: The laparoscopic approach may be safer and less invasive than laparotomy, and extracorporeal lymph node dissection is safe and reliable for patients with intestinal malrotation.

9.
Biol Reprod ; 104(2): 344-360, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33079185

RESUMO

Primordial germ cells (PGCs) are the founding population of the germ cell lineage that undergo a multistep process to generate spermatozoa or oocytes. Establishing an appropriate culture system for PGCs is a key challenge in reproductive biology. By a chemical screening using mouse PGC-like cells (mPGCLCs), which were induced from mouse embryonic stem cells, we reported previously that forskolin and rolipram synergistically enhanced the proliferation/survival of mPGCLCs with an average expansion rate of ~20-fold. In the present study, we evaluated other chemicals or cytokines to see whether they would improve the current mPGCLC culture system. Among the chemicals and cytokines examined, in the presence of forskolin and rolipram, cyclosporin A (CsA) and fibroblast growth factors (FGFs: FGF2 and FGF10) effectively enhanced the expansion of mPGCLCs in vitro (~50-fold on average). During the expansion by CsA or FGFs, mPGCLCs comprehensively erased their DNA methylation to acquire a profile equivalent to that of gonadal germ cells in vivo, while maintaining their highly motile phenotype as well as their transcriptional properties as sexually uncommitted PGCs. Importantly, these mPGCLCs robustly contributed to spermatogenesis and produced fertile offspring. Furthermore, mouse PGCs (mPGCs) cultured with CsA ex vivo showed transcriptomes and DNA methylomes similar to those of cultured mPGCLCs. The improved culture system for mPGCLCs/mPGCs would be instructive for addressing key questions in PGC biology, including the mechanisms for germ cell migration, epigenetic reprogramming, and sex determination of the germline.


Assuntos
Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ciclosporina/farmacologia , Fator 10 de Crescimento de Fibroblastos/farmacologia , Fator 2 de Crescimento de Fibroblastos/farmacologia , Células Germinativas/efeitos dos fármacos , Animais , Apoptose , Ciclo Celular , Proliferação de Células/fisiologia , Colforsina/farmacologia , Inibidores Enzimáticos/farmacologia , Células Germinativas/fisiologia , Camundongos , Rolitetraciclina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Sequenciamento Completo do Genoma
10.
Int J Surg Case Rep ; 75: 422-425, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33002853

RESUMO

INTRODUCTION: Edwardsiella tarda is a member of the Enterobacteriaceae family of gram-negative bacilli isolated from animals. Gastroenteritis is the most common manifestation of E. tarda infection. However, extraintestinal infections can occur in immunocompromised hosts as well as patients with hepatobiliary disease, malignancy, and/or diabetes mellites. The prognosis of sepsis caused by E. tarda is extremely poor, with a mortality rate of 38%. Here we report the occurrence of spontaneous bacterial peritonitis associated with E. tarda infection. PRESENTATION OF CASE: An 87-year-old man with Child-Pugh A cirrhosis secondary to hepatitis C virus infection presented with diarrhea and sudden-onset pain in the abdomen. On arrival, guarding and rebound tenderness were observed over the entire abdomen. Computed tomography revealed circumferential thickening of the cecum and a small volume of ascites in the pelvic cavity. A diagnosis of peritonitis was made, and surgery was performed. Surgical findings included redness and thickening of the cecal wall and purulent ascites without intestinal contents. Peritoneal fluid culture revealed E. tarda as the sole pathogen. The abdominal cavity was washed, a drain was placed in the pelvic cavity, and postoperative intravenous antibiotic therapy was initiated. The postoperative course was uneventful. DISCUSSION: E. tarda infection in the presence of an underlying disease such as hepatobiliary disease, malignancy, and/or diabetes mellitus has a poor prognosis. CONCLUSION: Although E. tarda infection is extremely rare, it is a life-threatening illness that can cause intestinal and extraintestinal infections. If necessary, early surgical intervention should be considered for cases of extraintestinal infection.

11.
Int J Surg Case Rep ; 75: 242-245, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32971445

RESUMO

INTRODUCTION: Solitary adrenal metastasis derived from colorectal cancer is rare. Adrenal metastasis is usually associated with systemic spread of the disease and is considered to be unsuitable for surgical resection. However, it has been reported that an aggressive surgical resection of adrenal metastasis results in improved overall survival in selected patients. We herein report an extremely rare case of complete resection of rectal cancer with a synchronous solitary adrenal metastasis. PRESENTATION OF CASE: A 70-year-old woman who presented with bloody stool was diagnosed with rectal cancer with a synchronous solitary adrenal metastasis and was suspected of having liver invasion. After a total of 2 cycles of chemotherapy with capecitabine and oxaliplatin, an abdominoperineal resection with D2 (proxD3) lymph node dissection and right adrenalectomy was performed and complete resection was possible. According to the TNM classification, the diagnosis was stage IVA (fT3N1bM1a[ADR]). At 18 months after surgery, the patient is alive with no evidence of recurrence and distant metastasis. DISCUSSION: Complete resection of adrenal metastasis may have a possibility of leading to a good prognosis in patients with a synchronous solitary adrenal metastasis. CONCLUSION: Adrenalectomy should be considered in patients who can undergo complete resection, as it may offer a good long-term prognosis.

12.
EMBO J ; 39(21): e104929, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-32954504

RESUMO

Human germ cells perpetuate human genetic and epigenetic information. However, the underlying mechanism remains elusive, due to a lack of appropriate experimental systems. Here, we show that human primordial germ cell-like cells (hPGCLCs) derived from human-induced pluripotent stem cells (hiPSCs) can be propagated to at least ~106 -fold over a period of 4 months under a defined condition in vitro. During expansion, hPGCLCs maintain an early hPGC-like transcriptome and preserve their genome-wide DNA methylation profiles, most likely due to retention of maintenance DNA methyltransferase activity. These characteristics contrast starkly with those of mouse PGCLCs, which, under an analogous condition, show a limited propagation (up to ~50-fold) and persist only around 1 week, yet undergo cell-autonomous genome-wide DNA demethylation. Importantly, upon aggregation culture with mouse embryonic ovarian somatic cells in xenogeneic-reconstituted ovaries, expanded hPGCLCs initiate genome-wide DNA demethylation and differentiate into oogonia/gonocyte-like cells, demonstrating their germline potential. By creating a paradigm for hPGCLC expansion, our study uncovers critical divergences in expansion potential and the mechanism for epigenetic reprogramming between the human and mouse germ cell lineage.


Assuntos
Células Germinativas/metabolismo , Ovário/embriologia , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Animais , Linhagem Celular , Desmetilação do DNA , Metilação de DNA , Células-Tronco Embrionárias/metabolismo , Epigênese Genética , Epigenômica , Feminino , Genoma , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Camundongos
13.
Immunology ; 158(4): 340-352, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31520477

RESUMO

Siglecs are cell surface lectins that recognize sialic acids and are primarily expressed in hematopoietic cells. Previous studies showed that some Siglecs regulate macrophage function. In the present study, we examined the induction and putative roles of mouse Siglec-F in bone-marrow-derived macrophages in mice. A quantitative RT-PCR analysis showed that the basal expression of Siglec-F was weak in bone-marrow-derived macrophages differentiated by macrophage colony-stimulating factor. However, a 24-hr stimulation with granulocyte-macrophage colony-stimulating factor (GM-CSF) enhanced Siglec-F expression. GM-CSF also enhanced Siglec-F expression in thioglycollate-induced peritoneal macrophages. The inhibition of signal transducer and activator of transcription 5 (STAT5), but not that of phosphoinositide 3-kinase or mitogen-activated protein kinase kinase, significantly reduced the induction of Siglec-F. Interleukin-3, which uses a common ß-chain shared with the GM-CSF receptor to stimulate the STAT5 pathway, also enhanced Siglec-F expression. The knockdown of Siglec-F by a specific small interfering RNA enhanced GM-CSF-induced STAT5 phosphorylation, suggesting that Siglec-F down-regulates its own expression upon prolonged GM-CSF stimulation. Furthermore, the knockdown of Siglec-F reduced the STAT6 phosphorylation and expression of arginase-1 in interleukin-4-stimulated macrophages. These results suggest that Siglec-F fine-tunes the immune responses of macrophages.


Assuntos
Antígenos de Diferenciação Mielomonocítica/metabolismo , Arginase/metabolismo , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Interleucina-4/metabolismo , Macrófagos/imunologia , Animais , Antígenos de Diferenciação Mielomonocítica/genética , Arginase/genética , Células Cultivadas , Interleucina-4/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , RNA Interferente Pequeno/genética , Fator de Transcrição STAT5/metabolismo , Fator de Transcrição STAT6/metabolismo , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico , Regulação para Cima
14.
Dev Biol ; 455(1): 32-41, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31271752

RESUMO

The differentiation of primordial germ cells (PGCs) is a fundamental step in development. PR domain-containing protein 14 (PRDM14) and B lymphocyte-induced maturation protein 1 (BLIMP1) play pivotal roles in mouse PGC specification. In the present study, we assessed the roles of chicken orthologs of PRDM14 and BLIMP1 in PGC development. PRDM14 and BLIMP1 were expressed in blastodermal cells and PGCs. The in vivo knockdown of PRDM14 or BLIMP1 by introducing a replication-competent retroviral vector expressing shRNAs to the blastodermal stage of embryos reduced the number of SSEA-1 or chicken vasa homologue-positive PGCs on day 5.5-6.5. Since the inhibition of Activin receptor-like kinase 4/5/7 in cultured PGCs reduced the expression of PRDM14, BLIMP1, and NANOG, and that of MEK inhibited PRDM14 expression, the expression of these genes seems to be controlled by Activin A and FGF2 signaling. Overall, PRDM14, BLIMP1, and NANOG seem to be involved in the self-renewal of PGCs in cultured PGCs and embryos.


Assuntos
Proteínas Aviárias/genética , Diferenciação Celular/genética , Regulação da Expressão Gênica no Desenvolvimento , Células Germinativas/metabolismo , Fator 1 de Ligação ao Domínio I Regulador Positivo/genética , Animais , Proteínas Aviárias/metabolismo , Blastoderma/citologia , Blastoderma/metabolismo , Autorrenovação Celular/genética , Células Cultivadas , Embrião de Galinha , Galinhas , Células Germinativas/citologia , Antígenos CD15/genética , Antígenos CD15/metabolismo , Proteína Homeobox Nanog/genética , Proteína Homeobox Nanog/metabolismo , Fator 1 de Ligação ao Domínio I Regulador Positivo/metabolismo , Interferência de RNA
15.
Vet Comp Oncol ; 17(2): 119-129, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30549190

RESUMO

Cancer stem-like cells (CSCs) are self-renewing cells comprising a small subpopulation in tumours, and generate differentiated progeny through asymmetric division. It has been shown that CSCs are resistant to ionizing radiation, and this feature could be one of the mechanisms of tumour recurrence after radiation therapy. Much attention has been focused on to target CSCs; however, difficult of isolating CSCs and lack of knowledge on their radiosensitivity have limited this kind of research in veterinary medicine. In the present study, sphere-forming cells (SC), cultured using sphere formation method, were isolated from four type of canine tumour cell lines and evaluated if they have CSCs-like properties by expression of CSCs markers (real-time polymerase chain reaction) and capacity of tumorigenesis (xenograft transplantation in nude mice), and were assessed radiosensitivity (clonogenic survival assay) and DNA repair kinetics (immunofluorescence staining for p53-binding protein 1) after X-ray irradiation in comparison with the corresponding normal adherent culture cells (AC). All SCs were isolated using sphere formation and showed high gene expression of CD133 and tumorigenic ability as compared with AC. All SCs were significantly resistant against X-ray irradiation as compared with AC. In addition, the amount of DNA double-strand breaks after X-ray irradiation were significantly lower in SC compared with the corresponding AC. These results indicate that SC isolated through sphere formation possess CSCs-like characteristics and CSCs are important factor that affect radiosensitivity in canine tumours. In addition, radioresistance of CSCs may depend on reaction of DNA double-strand break after X-ray exposure.


Assuntos
Células-Tronco Neoplásicas/efeitos da radiação , Esferoides Celulares/efeitos da radiação , Animais , Linhagem Celular Tumoral , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Doenças do Cão/radioterapia , Cães , Feminino , Marcadores Genéticos , Camundongos , Camundongos Nus , Tolerância a Radiação , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Células-Tronco , Sobrevida
16.
Gan To Kagaku Ryoho ; 45(10): 1546-1548, 2018 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-30382073

RESUMO

Immunological checkpoint inhibitors have effects on various advancedcancers. Nivolumab was approvedfor advanced gastric cancer after third-line treatment in 2017. In our hospital, 10 patients were treatedwith nivolumab from October 2017 to March 2018. Thus, we retrospectively examinedthe clinical background, treatment outcomes, andad verse events of those patients. The median age was 70 years; male-to-female ratio was 6:4; recurrence sites were peritoneal dissemination, liver, lymph nodes, brain, ovaries, and bone(8, 2, 2, 1, 1, and1 , respectively); andtreatment lines were third, fourth, andfifth(in 6, 3, and1 patients, respectively). The minimum number of cycles was 1 course, while the maximum was 11 courses. The best tumor response evaluation was SD, andthe adverse event was an itching sensation in only one patient. It was suggestedthat long-term SD couldbe maintainedwhen the nivolumab treatment was initiatedin a patient with goodPS. In the future, biomarker analysis is expectedto identify effective cases.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Nivolumabe/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Idoso , Feminino , Gastrectomia , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estudos Retrospectivos , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia
17.
Science ; 362(6412): 356-360, 2018 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-30237246

RESUMO

Human in vitro gametogenesis may transform reproductive medicine. Human pluripotent stem cells (hPSCs) have been induced into primordial germ cell-like cells (hPGCLCs); however, further differentiation to a mature germ cell has not been achieved. Here, we show that hPGCLCs differentiate progressively into oogonia-like cells during a long-term in vitro culture (approximately 4 months) in xenogeneic reconstituted ovaries with mouse embryonic ovarian somatic cells. The hPGCLC-derived oogonia display hallmarks of epigenetic reprogramming-genome-wide DNA demethylation, imprint erasure, and extinguishment of aberrant DNA methylation in hPSCs-and acquire an immediate precursory state for meiotic recombination. Furthermore, the inactive X chromosome shows a progressive demethylation and reactivation, albeit partially. These findings establish the germline competence of hPSCs and provide a critical step toward human in vitro gametogenesis.


Assuntos
Técnicas de Reprogramação Celular/métodos , Células-Tronco Pluripotentes Induzidas/citologia , Oogênese , Oogônios/citologia , Ovário/crescimento & desenvolvimento , Metilação de DNA , Epigênese Genética , Feminino , Humanos
18.
Cytotechnology ; 69(3): 477-484, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27117301

RESUMO

In mammals, interferon-inducible transmembrane proteins (IFITMs) prevent infections by various enveloped viruses. The expression of IFITMs in chicken was herein examined in the adult and embryonic organs using a quantitative reverse-transcription-polymerase chain reaction. The results obtained revealed that IFITM3 was expressed at a higher level than IFITM1, 2 and 5, in both embryonic and adult organs. However, the expression levels of IFITMs in embryonic organs were less than 5 % of those in adult lungs. Among the embryonic tissues examined, primordial germ cells (PGCs) at day 2.5 expressed relatively higher levels of IFITM3. IFITM3 expression levels were 1.5-fold higher in the chicken cell line DF-1 than in PGCs. The knockdown of IFITM3 in DF-1 cells by siRNA increased the infectivity of a vesicular stomatitis virus G protein-pseudotyped lentiviral vector, suggesting that lower levels of IFITM3 are still sufficient to restrict this viral vector.

19.
World J Surg Oncol ; 14(1): 47, 2016 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-26912337

RESUMO

BACKGROUND: Carcinoma and adenoma of the duodenum, including the papilla of Vater, are problematic diseases in patients with familial adenomatous polyposis (FAP). CASE PRESENTATION: A 36-year-old man underwent a periodic medical examination for early colon cancer originating from FAP for which laparoscopic-assisted subtotal colectomy with a J-shaped ileal pouch-rectal anastomosis was performed 3 years earlier. A tumor was detected at the papilla of Vater along with elevation of total bilirubin and hepatobiliary enzymes. Although cytology did not determine the tumor to be an adenocarcinoma, we suspected adenocarcinoma due to its hypervascularity shown by contrast-enhanced computed tomography. Pylorus-preserving pancreaticoduodenectomy with modified Imanaga reconstruction and regional lymph node dissection (D2) was performed. The pathological study showed that the tumor was a papillary and moderately differentiated tubular adenocarcinoma. The patient is currently in good health without recurrence, weight loss, or severe diarrhea at 12 months after surgery. CONCLUSIONS: Awareness of biliary-pancreatic symptoms and periodic gastroduodenoscopy might contribute both to the early detection of duodenal or periampullary polyps and cancer and to the radical treatment of FAP. Modified Imanaga reconstruction has the potential to become one of the more effective procedures for providing good quality of life to FAP patients with duodenal or periampullary cancer.


Assuntos
Polipose Adenomatosa do Colo/cirurgia , Ampola Hepatopancreática/patologia , Colectomia/efeitos adversos , Neoplasias do Ducto Colédoco/etiologia , Complicações Pós-Operatórias , Adulto , Ampola Hepatopancreática/cirurgia , Neoplasias do Ducto Colédoco/patologia , Neoplasias do Ducto Colédoco/cirurgia , Humanos , Masculino , Prognóstico
20.
Biosci Biotechnol Biochem ; 80(3): 501-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26540411

RESUMO

Siglecs, an immunoglobulin-like lectin family that recognizes the sialic acid moiety, regulate various aspects of immune responses. In the present study, we investigated the effects of Siglecs on the macrophage cell line RAW264, which was stimulated with interleukin-4 (IL-4). The induction of arginase-1 (Arg1) by IL-4 was stronger in Siglec-9-expressing cells than in mock cells. Mutations in the cytoplasmic tyrosine-based inhibitory motifs in Siglec-9 markedly reduced the expression of Arg1. The phosphorylation of Akt by IL-4 and extracellular signal-regulated kinase (ERK) without IL-4 was stronger in Siglec-9-expressing cells, indicating the enhanced activation of the phosphatidylinositol 3 kinase (PI-3K) and mitogen-activated protein kinase kinase (MEK)/ERK pathways, respectively. The enhanced expression of Arg1 was inhibited by MEK inhibitors, but not by PI-3K inhibitor. These results indicate that Siglec-9 affects several different signaling pathways in IL-4-stimulated macrophages, which resulted in enhanced induction of Arg1 in Siglec-9-expressing RAW264 cells.


Assuntos
Interleucina-4/fisiologia , Macrófagos/imunologia , Animais , Antígenos CD , Antígenos de Diferenciação de Linfócitos B , Arginase/metabolismo , Linhagem Celular , Células Cultivadas , Humanos , Sistema de Sinalização das MAP Quinases , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Fator de Transcrição STAT6/metabolismo
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