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2.
Chromosome Res ; 31(3): 17, 2023 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-37353691

RESUMO

Telomerase is a ribonucleoprotein ribonucleic enzyme that elongates telomere repeat sequences at the ends of chromosomes and contributes to cellular immortalization. The catalytic component of telomerase, human telomerase reverse transcriptase (hTERT), has been observed to be reactivated in immortalized cells. Notably, most cancer cells have been found to have active hTERT mRNA transcription, resulting in continuous cell division, which is crucial for malignant transformation. Therefore, discovering mechanisms underlying the regulation of hTERT transcription is an attractive target for cancer-specific treatments.Loss of heterozygosity (LOH) of chromosome 3p21.3 has been frequently observed in human oral squamous cell carcinoma (OSCC). Moreover, we previously reported that HSC3 OSCC microcell hybrid clones with an introduced human chromosome 3 (HSC3#3) showed inhibition of hTERT transcription compared with the parental HSC3 cells. This study examined whether hTERT transcription regulators are present in the 3p21.3 region. We constructed a human artificial chromosome (HAC) vector (3p21.3-HAC) with only the 3p21.3-p22.2 region and performed functional analysis using the 3p21.3-HAC. HSC3 microcell hybrid clones with an introduced 3p21.3-HAC exhibited significant suppression of hTERT transcription, similar to the microcell hybrid clones with an intact chromosome 3. In contrast, HSC3 clones with truncated chromosome 3 with deletion of the 3p21.3 region (3delp21.3) showed no effect on hTERT expression levels. These results provide direct evidence that hTERT suppressor gene(s) were retained in the 3p21.3 region, suggesting that the presence of regulatory factors that control telomerase enzyme activity may be involved in the development of OSCC.


Assuntos
Carcinoma de Células Escamosas , Cromossomos Artificiais Humanos , Neoplasias Bucais , Telomerase , Humanos , Telomerase/genética , Telomerase/metabolismo , Carcinoma de Células Escamosas/genética , Cromossomos Artificiais Humanos/metabolismo , Neoplasias Bucais/genética , Transcrição Gênica
3.
Sci Rep ; 13(1): 4225, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36918661

RESUMO

We previously generated fully human antibody-producing TC-mAb mice for obtaining potential therapeutic monoclonal antibodies (mAbs). In this study, we investigated 377 clones of fully human mAbs against a tumor antigen, epithelial cell adhesion molecule (EpCAM), to determine their antigen binding properties. We revealed that a wide variety of mAbs against EpCAM can be obtained from TC-mAb mice by the combination of epitope mapping analysis of mAbs to EpCAM and native conformational recognition analysis. Analysis of 72 mAbs reacting with the native form of EpCAM indicated that the EpCL region (amino acids 24-80) is more antigenic than the EpRE region (81-265), consistent with numerous previous studies. To evaluate the potential of mAbs against antibody-drug conjugates, mAbs were directly labeled with DM1, a maytansine derivative, using an affinity peptide-based chemical conjugation (CCAP) method. The cytotoxicity of the conjugates against a human colon cancer cell line could be clearly detected with high-affinity as well as low-affinity mAbs by the CCAP method, suggesting the advantage of this method. Thus, this study demonstrated that TC-mAb mice can provide a wide variety of antibodies and revealed an effective way of identifying candidates for fully human ADC therapeutics.


Assuntos
Neoplasias do Colo , Imunoconjugados , Humanos , Camundongos , Animais , Imunoconjugados/farmacologia , Imunoconjugados/uso terapêutico , Molécula de Adesão da Célula Epitelial , Antígenos de Neoplasias , Neoplasias do Colo/patologia , Anticorpos Monoclonais
4.
Oncol Lett ; 23(3): 92, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35154423

RESUMO

Bladder cancer is divided into two molecular subtypes, luminal and basal, which form papillary and nodular tumors, respectively, and are identifiable by gene expression profiling. Although loss of heterozygosity (LOH) of the long arm of human chromosome 9 (9q) has been observed in the early development of both types of bladder cancer, the functional significance of LOH remains to be clarified. The present study introduced human chromosome 9q into basal bladder cancer cell line, SCaBER, using microcell-mediated chromosome transfer to investigate the effect of LOH of 9q on molecular bladder cancer subtypes. These cells demonstrated decreased proliferation and migration capacity compared with parental and control cells. Conversely, transfer of human chromosome 4 did not change the cell phenotype. Expression level of peroxisome proliferator-activated receptor (PPAR)γ, a marker of luminal type, increased 3.0-4.4 fold in SCaBER cells altered with 9q compared with parental SCaBER cells. Furthermore, the expression levels of tumor suppressor PTEN, which regulates PPARγ, also increased in 9q-altered cells. These results suggested that human chromosome 9q may carry regulatory genes for PPARγ that are involved in the progression of neoplastic transformation of bladder cancer.

5.
Diagn Pathol ; 17(1): 16, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35094710

RESUMO

INSTRUCTION: The human amphoterin-induced gene and open reading frame (AMIGO) was identified as a novel cell adhesion molecule of type I transmembrane protein. AMIGO2 is one of three members of the AMIGO family (AMIGO1, 2, and 3), and the similarity between them is approximately 40% at the amino acid level. We have previously shown that AMIGO2 functions as a driver of liver metastasis. Immunohistochemical analysis of AMIGO2 expression in colorectal cancer (CRC) using a commercially available anti-AMIGO2 mouse monoclonal antibody clone sc-373699 (sc mAb) correlated with liver metastasis and poor prognosis. However, the sc mAb was found to be cross-reactive with all three molecules in the AMIGO family. METHODS: We generated a rat monoclonal antibody clone rTNK1A0012 (rTNK mAb) for human AMIGO2. The rTNK mAb was used to re-evaluate the association between AMIGO2 expression and liver metastases/clinical outcomes using the same CRC tissue samples previously reported with sc mAb. RESULTS: Western blot analysis revealed that a rTNK mAb was identified as being specific for AMIGO2 protein and did not cross-react with AMIGO1 and AMIGO3. The rTNK mAb and sc mAb showed higher AMIGO2 expression, which correlates with a high frequency of liver metastases (65.3% and 47.5%, respectively), while multivariate analysis showed that AMIGO2 expression was an independent prognostic factor for liver metastases (p = 7.930E-10 and p = 1.707E-5). The Kaplan-Meier analyses showed that the rTNK mAb (p = 0.004), but not sc mAb (p = 0.107), predicted worse overall survival in patients with high AMIGO2 expression. The relationship between AMIGO2 expression and poor disease-specific survival showed a higher level of significance for rTNK mAb (p = 0.00004) compared to sc mAb (p = 0.001). CONCLUSIONS: These results indicate that the developed rTNK1A0012 mAb is an antibody that specifically recognizes AMIGO2 by immunohistochemistry and can be a more reliable and applicable method for the diagnostic detection of liver metastases and worse prognosis in patients with high AMIGO2-expressing CRC.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Animais , Neoplasias Colorretais/patologia , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/secundário , Proteínas de Membrana/genética , Camundongos , Proteínas do Tecido Nervoso/genética , Prognóstico , Ratos
6.
Nat Aging ; 2(1): 31-45, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-37118356

RESUMO

Senescence is a fate-determined state, accompanied by reorganization of heterochromatin. Although lineage-appropriate genes can be temporarily repressed through facultative heterochromatin, stable silencing of lineage-inappropriate genes often involves the constitutive heterochromatic mark, histone H3 lysine 9 trimethylation (H3K9me3). The fate of these heterochromatic genes during senescence is unclear. In the present study, we show that a small number of lineage-inappropriate genes, exemplified by the LCE2 skin genes, are derepressed during senescence from H3K9me3 regions in fibroblasts. DNA FISH experiments reveal that these gene loci, which are condensed at the nuclear periphery in proliferative cells, are decompacted during senescence. Decompaction of the locus is not sufficient for LCE2 expression, which requires p53 and C/EBPß signaling. NLRP3, which is predominantly expressed in macrophages from an open topologically associated domain (TAD), is also derepressed in senescent fibroblasts due to the local disruption of the H3K9me3-rich TAD that contains it. NLRP3 has been implicated in the amplification of inflammatory cytokine signaling in senescence and aging, highlighting the functional relevance of gene induction from 'permissive' H3K9me3 regions in senescent cells.


Assuntos
Heterocromatina , Histonas , Heterocromatina/genética , Histonas/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Senescência Celular/genética , Expressão Gênica
7.
Mol Med Rep ; 25(1)2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34779499

RESUMO

Our previous study revealed that metastasis­associated protein 1 (MTA1), which is expressed in vascular endothelial cells, acts as a tube formation promoting factor. The present study aimed to clarify the importance of MTA1 expression in tube formation using MTA1­knockout (KO) endothelial cells (MTA1­KO MSS31 cells). Tube formation was significantly suppressed in MTA1­KO MSS31 cells, whereas MTA1­overexpression MTA1­KO MSS31 cells regained the ability to form tube­like structures. In addition, western blotting analysis revealed that MTA1­KO MSS31 cells showed significantly higher levels of phosphorylation of non­muscle myosin heavy chain IIa, which resulted in suppression of tube formation. This effect was attributed to a decrease of MTA1/S100 calcium­binding protein A4 complex formation. Moreover, inhibition of tube formation in MTA1­KO MSS31 cells could not be rescued by stimulation with vascular endothelial growth factor (VEGF). These results demonstrated that MTA1 may serve as an essential molecule for angiogenesis in endothelial cells and be involved in different steps of the angiogenic process compared with the VEGF/VEGF receptor 2 pathway. The findings showed that endothelial MTA1 and its pathway may serve as promising targets for inhibiting tumor angiogenesis, further supporting the development of MTA1­based antiangiogenic therapies.


Assuntos
Células Endoteliais/metabolismo , Neovascularização Patológica/metabolismo , Proteínas Repressoras/metabolismo , Transativadores/metabolismo , Inibidores da Angiogênese/farmacologia , Animais , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Células Cultivadas , China , Camundongos , Morfogênese/efeitos dos fármacos , Cadeias Pesadas de Miosina/metabolismo , Metástase Neoplásica/genética , Fosforilação , Proteínas Repressoras/fisiologia , Proteína A4 de Ligação a Cálcio da Família S100/metabolismo , Transativadores/fisiologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Fatores de Crescimento do Endotélio Vascular/metabolismo
8.
Sci Rep ; 11(1): 18405, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526609

RESUMO

Melanoma is one of the most aggressive types of cancer wherein resistance to treatment prevails. Therefore, it is important to discover novel molecular targets of melanoma progression as potential treatments. Here we show that paired-like homeodomain transcription factor 1 (PITX1) plays a crucial role in the inhibition of melanoma progression through regulation of SRY-box transcription factors (SOX) gene family mRNA transcription. Overexpression of PITX1 in melanoma cell lines resulted in a reduction in cell proliferation and an increase in apoptosis. Additionally, analysis of protein levels revealed an antagonistic cross-regulation between SOX9 and SOX10. Interestingly, PITX1 binds to the SOX9 promoter region as a positive regulatory transcription factor; PITX1 mRNA expression levels were positively correlated with SOX9 expression, and negatively correlated with SOX10 expression in melanoma tissues. Furthermore, transcription of the long noncoding RNA (lncRNA), survival-associated mitochondrial melanoma-specific oncogenic noncoding RNA (SAMMSON), was decreased in PITX1-overexpressing cells. Taken together, the findings in this study indicate that PITX1 may act as a negative regulatory factor in the development and progression of melanoma via direct targeting of the SOX signaling.


Assuntos
Regulação Neoplásica da Expressão Gênica , Melanoma/genética , Melanoma/metabolismo , Família Multigênica , Fatores de Transcrição Box Pareados/metabolismo , Fatores de Transcrição SOX/genética , Animais , Apoptose/genética , Sequência de Bases , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células , Sequenciamento de Cromatina por Imunoprecipitação , Modelos Animais de Doenças , Elementos Facilitadores Genéticos , Perfilação da Expressão Gênica , Xenoenxertos , Humanos , Melanoma/patologia , Camundongos , Modelos Biológicos , Regiões Promotoras Genéticas , Ligação Proteica , Fatores de Transcrição SOX/metabolismo
9.
Sci Rep ; 11(1): 15355, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34321527

RESUMO

Frequent loss of heterozygosity (LOH) on the short arm of human chromosome 3 (3p) region has been found in pancreatic cancer (PC), which suggests the likely presence of tumor suppressor genes in this region. However, the functional significance of LOH in this region in the development of PC has not been clearly defined. The human telomerase reverse transcriptase gene (hTERT) contributes to unlimited proliferative and tumorigenicity of malignant tumors. We previously demonstrated that hTERT expression was suppressed by the introduction of human chromosome 3 in several cancer cell lines. To examine the functional role of putative TERT suppressor genes on chromosome 3 in PC, we introduced an intact human chromosome 3 into the human PK9 and murine LTPA PC cell lines using microcell-mediated chromosome transfer. PK9 microcell hybrids with an introduced human chromosome 3 showed significant morphological changes and rapid growth arrest. Intriguingly, microcell hybrid clones of LTPA cells with an introduced human chromosome 3 (LTPA#3) showed suppression of mTert transcription, cell proliferation, and invasion compared with LTPA#4 cells containing human chromosome 4 and parental LTPA cells. Additionally, the promoter activity of mTert was downregulated in LTPA#3. Furthermore, we confirmed that TERT regulatory gene(s) are present in the 3p21.3 region by transfer of truncated chromosomes at arbitrary regions. These results provide important information on the functional significance of the LOH at 3p for development and progression of PC.


Assuntos
Carcinogênese/genética , Quimera/genética , Cromossomos Humanos Par 3/química , Perda de Heterozigosidade , Neoplasias Pancreáticas/genética , Telomerase/genética , Animais , Carcinogênese/metabolismo , Carcinogênese/patologia , Linhagem Celular Tumoral , Proliferação de Células , Cromossomos Humanos Par 3/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Invasividade Neoplásica , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Regiões Promotoras Genéticas , Telomerase/metabolismo , Transcrição Gênica
10.
Sci Adv ; 7(3)2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33523882

RESUMO

Fragile X-related tremor/ataxia syndrome (FXTAS) is a neurodegenerative disease caused by CGG triplet repeat expansions in FMR1, which elicit repeat-associated non-AUG (RAN) translation and produce the toxic protein FMRpolyG. We show that FMRpolyG interacts with pathogenic CGG repeat-derived RNA G-quadruplexes (CGG-G4RNA), propagates cell to cell, and induces neuronal dysfunction. The FMRpolyG polyglycine domain has a prion-like property, preferentially binding to CGG-G4RNA. Treatment with 5-aminolevulinic acid, which is metabolized to protoporphyrin IX, inhibited RAN translation of FMRpolyG and CGG-G4RNA-induced FMRpolyG aggregation, ameliorating aberrant synaptic plasticity and behavior in FXTAS model mice. Thus, we present a novel therapeutic strategy to target G4RNA prionoids.


Assuntos
Síndrome do Cromossomo X Frágil , Quadruplex G , Doenças Neurodegenerativas , Animais , Ataxia/genética , Ataxia/metabolismo , Ataxia/patologia , Proteína do X Frágil da Deficiência Intelectual/genética , Síndrome do Cromossomo X Frágil/genética , Camundongos , Tremor/genética , Tremor/metabolismo
11.
Exp Cell Res ; 398(2): 112419, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33296661

RESUMO

Fragile X syndrome (FXS) is the most common inheritable form of intellectual disability. FMR1, the gene responsible for FXS, is located on human chromosome Xq27.3 and contains a stretch of CGG trinucleotide repeats in its 5' untranslated region. FXS is caused by CGG repeats that expand beyond 200, resulting in FMR1 silencing via promoter hypermethylation. The molecular mechanism underlying CGG repeat expansion, a fundamental cause of FXS, remains poorly understood, partly due to a lack of experimental systems. Accumulated evidence indicates that the large chromosomal region flanking a CGG repeat is critical for repeat dynamics. In the present study, we isolated and introduced whole human X chromosomes from healthy, FXS premutation carriers, or FXS patients who carried disease condition-associated CGG repeat lengths, into mouse A9 cells via microcell-mediated chromosome transfer. The CGG repeat length-associated methylation status and human FMR1 expression in these monochromosomal hybrid cells mimicked those in humans. Thus, this set of A9 cells containing CGG repeats from three different origins (FXS-A9 panel) may provide a valuable resource for investigating a series of genetic and epigenetic CGG repeat dynamics during FXS pathogenesis.


Assuntos
Cromossomos Humanos X/genética , Síndrome do Cromossomo X Frágil/genética , Animais , Células Cultivadas , Cromossomos Humanos X/metabolismo , Cricetulus , Proteína do X Frágil da Deficiência Intelectual/genética , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Síndrome do Cromossomo X Frágil/metabolismo , Síndrome do Cromossomo X Frágil/patologia , Humanos , Camundongos , Repetições de Trinucleotídeos/genética
12.
Pharmacol Res Perspect ; 8(5): e00642, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32886454

RESUMO

The fields of drug discovery and regenerative medicine require large numbers of adult human primary hepatocytes. For this purpose, it is desirable to use hepatocyte-like cells (HLCs) differentiated from human pluripotent stem cells (PSCs). Premature hepatoblast-like cells (HB-LCs) differentiated from PSCs provide an intermediate source and steady supply of newly mature HLCs. To develop an efficient HB-LC induction method, we constructed a red fluorescent reporter, CYP3A7R, in which DsRed is placed under the transcriptional control of CYP3A7 coding for a human fetus-type P450 enzyme. Before using this reporter in human cells, we created transgenic mice using mouse embryonic stem cells (ESCs) carrying a CYP3A7R transgene and confirmed that CYP3A7R was specifically expressed in fetal and newborn livers and reactivated in the adult liver in response to hepatic regeneration. Moreover, we optimized the induction procedure of HB-LCs from transgenic mouse ESCs using semi-quantitative fluorometric evaluation. Activation of Wnt signaling together with chromatin modulation prior to Activin A treatment greatly improved the induction efficiency of HB-LCs. BMP2 and 1.7% dimethyl sulfoxide induced selective proliferation of HB-LCs, which matured to HLCs. Therefore, CYP3A7R will provide a fluorometric evaluation system for high content screening of chemicals that induce HB-LC differentiation, hepatocyte regeneration, and hepatotoxicity when it is introduced into human PSCs.


Assuntos
Citocromo P-450 CYP3A/genética , Hepatócitos/citologia , Regeneração Hepática , Fígado/embriologia , Proteínas Luminescentes/metabolismo , Células-Tronco Embrionárias Murinas/citologia , Animais , Proteína Morfogenética Óssea 2/metabolismo , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Citocromo P-450 CYP3A/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Hepatócitos/metabolismo , Humanos , Fígado/metabolismo , Fígado/fisiologia , Proteínas Luminescentes/genética , Camundongos , Camundongos Transgênicos , Microscopia de Fluorescência , Células-Tronco Embrionárias Murinas/metabolismo , Proteínas Recombinantes/metabolismo , Via de Sinalização Wnt , Proteína Vermelha Fluorescente
13.
Biotechnol Lett ; 42(5): 697-705, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32006350

RESUMO

OBJECTIVE: To develop a mouse artificial chromosome (MAC) carrying the mouse Xist gene (X-inactive specific transcript; Xist-MAC) as a systematic in vitro approach for investigating Xist RNA-mediated chromosome inactivation. RESULTS: Ectopic expression of the Xist gene in CHO cells led to the accumulation of Xist RNA in cis on the MAC. In addition, the introduction of Xist-MAC to embryonic stem cells from male mice via microcell-mediated chromosome transfer resulted in the accumulation of Xist RNA in cis on the MAC. Chromosomal inactivation was observed in the differentiated state. Moreover, this phenomenon was accompanied by the epigenetic modification of H3K27 trimethylation. CONCLUSIONS: We successfully generated a novel chromosome inactivation model, Xist-MAC, which will provide a valuable tool for the screening and functional analysis of X chromosome inactivation-related genes and proteins.


Assuntos
Cromossomos Artificiais/genética , Células-Tronco Embrionárias/citologia , Histonas/metabolismo , RNA Longo não Codificante/genética , Animais , Células CHO , Células Cultivadas , Cricetulus , Epigênese Genética , Masculino , Camundongos , Inativação do Cromossomo X
14.
Sci Rep ; 9(1): 16954, 2019 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-31740706

RESUMO

Gene amplification methods play a crucial role in establishment of cells that produce high levels of recombinant protein. However, the stability of such cell lines and the level of recombinant protein produced continue to be suboptimal. Here, we used a combination of a human artificial chromosome (HAC) vector and initiation region (IR)/matrix attachment region (MAR) gene amplification method to establish stable cells that produce high levels of recombinant protein. Amplification of Enhanced green fluorescent protein (EGFP) was induced on a HAC carrying EGFP gene and IR/MAR sequences (EGFP MAR-HAC) in CHO DG44 cells. The expression level of EGFP increased approximately 6-fold compared to the original HAC without IR/MAR sequences. Additionally, anti-vascular endothelial growth factor (VEGF) antibody on a HAC (VEGF MAR-HAC) was also amplified by utilization of this IR/MAR-HAC system, and anti-VEGF antibody levels were approximately 2-fold higher compared with levels in control cells without IR/MAR. Furthermore, the expression of anti-VEGF antibody with VEGF MAR-HAC in CHO-K1 cells increased 2.3-fold compared with that of CHO DG44 cells. Taken together, the IR/MAR-HAC system facilitated amplification of a gene of interest on the HAC vector, and could be used to establish a novel cell line that stably produced protein from mammalian cells.


Assuntos
Cromossomos Artificiais Humanos , Engenharia de Proteínas/métodos , Proteínas Recombinantes/genética , Animais , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/metabolismo , Células CHO , Cricetulus , Vetores Genéticos , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Regiões de Interação com a Matriz/genética , Técnicas de Amplificação de Ácido Nucleico , Proteínas Recombinantes/metabolismo , Fator A de Crescimento do Endotélio Vascular/imunologia
15.
PLoS One ; 14(8): e0217605, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31404068

RESUMO

Telomerase is a ribonucleoprotein ribonucleic enzyme that is essential for cellular immortalization via elongation of telomere repeat sequences at the end of chromosomes. Human telomerase reverse transcriptase (hTERT), the catalytic subunit of telomerase holoenzyme, is a key regulator of telomerase activity. Telomerase activity, which has been detected in the majority of cancer cells, is accompanied by hTERT expression, suggesting that this enzyme activity contributes to an unlimited replication potential of cancer cells via regulation of telomere length. Thus, hTERT is an attractive target for cancer-specific treatments. We previously reported that pared-like homeodomain 1 (PITX1) is a negative regulator of hTERT through direct binding to the hTERT promoter. However, the mechanism by which the function of PITX1 contributes to transcriptional silencing of the hTERT gene remains to be clarified. Here, we show that PITX1 and zinc finger CCHC-type containing 10 (ZCCHC10) proteins cooperate to facilitate the transcriptional regulation of the hTERT gene by functional studies via FLAG pull-down assay. Co-expression of PITX1 and ZCCHC10 resulted in inhibition of hTERT transcription, in melanoma cell lines, whereas mutate-deletion of homeodomain in PITX1 that interact with ZCCHC10 did not induce similar phenotypes. In addition, ZCCHC10 expression levels showed marked decrease in the majority of melanoma cell lines and tissues. Taken together, these results suggest that ZCCHC10-PITX1 complex is the functional unit that suppresses hTERT transcription, and may play a crucial role as a novel tumor suppressor complex.


Assuntos
Regulação Enzimológica da Expressão Gênica , Melanoma/metabolismo , Fatores de Transcrição Box Pareados/metabolismo , RNA Mensageiro/metabolismo , Telomerase/metabolismo , Fatores de Transcrição/metabolismo , Dedos de Zinco/genética , Humanos , Melanoma/genética , Fatores de Transcrição Box Pareados/genética , Regiões Promotoras Genéticas , Domínios e Motivos de Interação entre Proteínas , RNA Mensageiro/genética , Telomerase/genética , Fatores de Transcrição/genética , Transcrição Gênica , Células Tumorais Cultivadas
16.
Yonago Acta Med ; 62(1): 67-76, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30962747

RESUMO

BACKGROUND: Adenoid cystic carcinoma (ACC) is a relatively rare malignant neoplasm that occurs in salivary glands and various other organs. Recent studies have revealed that a significant proportion of ACCs harbor gene alterations involving MYB or MYBL1 (mostly fusions with NFIB) in a mutually-exclusive manner. However, its clinical significance remains to be well-established. METHODS: We investigated clinicopathological and molecular features of 36 ACCs with special emphasis on the significance of MYBL1 alterations. Reverse-transcription polymerase-chain reaction (RT-PCR) and fluorescence in-situ hybridization (FISH) were performed to detect MYB/MYBL1-NFIB fusions and MYBL1 alterations, respectively. Immunohistochemistry was performed to evaluate MYB expression in the tumors. The results were correlated with clinicopathological profiles of the patients. RESULTS: RT-PCR revealed MYB-NFIB and MYBL1-NFIB fusions in 10 (27.8%) and 7 (19.4%) ACCs, respectively, in a mutually-exclusive manner. FISH for MYBL1 rearrangements was successfully performed in 11 cases, and the results were concordant with those of RT-PCR. Immunohistochemically, strong MYB expression was observed in 23 (63.9%) tumors, none of which showed MYBL1 alterations. Clinicopathologically, a trend of a better disease-specific survival was noted in patients with MYBL1 alterations than in those with MYB-NFIB fusions and/or strong MYB expression; however, the difference was not significant. Interestingly, we found tumors with MYBL1 alterations significantly frequently occurred in the mandibular regions (P = 0.012). Moreover, literature review revealed a similar tendency in a previous study. CONCLUSION: Our results suggest that there are some biological or etiological differences between ACCs with MYB and MYBL1 alterations. Moreover, the frequent occurrence of MYBL1-associated ACC in the mandibular regions suggests that MYB immunohistochemistry is less useful in diagnosing ACCs arising in these regions. Further studies are warranted to verify our findings.

17.
Anticancer Res ; 37(6): 2985-2992, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28551636

RESUMO

AIM: To generate sunitinib-resistant renal cell carcinoma (RCC) cell lines and identify miRNAs contributing to sunitinib resistance. MATERIALS AND METHODS: Two RCC cell lines, ACHN and RCC23, were cultured by continuous treatment with sunitinib for 3 months, with doses gradually increasing up to the 50% inhibitory concentration for each cell line. We performed microarray and quantitative real-time polymerase chain reaction analyses of sunitinib-resistant ACHN (SR-ACHN) and RCC23 (SR-RCC23) cells, as well of as sunitinib-sensitive ACHN and RCC23 cells. RESULTS: SR-ACHN and SR-RCC23 cells exhibited significantly higher resistance to sunitinib treatment compared to sunitinib-sensitive cells. SR-ACHN and SR-RCC23 cells were hypertrophic and contained granules in the cytoplasm. When SR-ACHN and SR-RCC23 cells were compared to ACHN and RCC23 cells, expression of miR-575, miR-642b-3p, and miR-4430 was significantly increased, while that of miR-18a-5p, miR-29b-1-5p, miR-431-3p, and miR-4521 was significantly decreased. CONCLUSION: These miRNAs may contribute to sunitinib resistance in humans.


Assuntos
Antineoplásicos/farmacologia , Carcinoma de Células Renais/genética , Resistencia a Medicamentos Antineoplásicos/genética , Indóis/farmacologia , Neoplasias Renais/genética , MicroRNAs/genética , Pirróis/farmacologia , Linhagem Celular Tumoral , Humanos , Sunitinibe
18.
Mol Clin Oncol ; 5(1): 89-94, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27330773

RESUMO

The pituitary homeobox 1 (PITX1) protein is essential for developmental processes in humans. Previously, PITX1 was identified as a possible tumor suppressor gene in various types of human carcinoma. However, the association between PITX1 and human head and neck squamous cell carcinoma (HNSCC) remains to be elucidated. Immunohistochemical analysis was performed to examine the expression levels of PITX1 in 47 cases of HNSCC, and in 4 control cases. The expression of p53 was also examined in these cases. The labeling indices (LIs) were calculated, and the correlations between clinical factors (chemosensitivity, prognosis and the degree of differentiation) and the LIs were assessed. The PITX1 LI in HNSCC was 27.4±14.5%, which was significantly lower compared with the LIs of the control samples: 76.9±6.97% (P<0.05). Additionally, the PITX1 LIs were 39.9±6.2, 26.9±16.9 and 24.2±11.8% in the complete response (CR), partial response (PR), stable disease or progressive disease (SD/PD) groups, respectively. The PITX1 LI in the CR group revealed the highest result between the all groups, and it was significantly greater compared with that in the SD/PD group (P<0.01). The p53 LIs were 24.5±19.9, 25.7±16.9 and 19.8±13.8 in the CR, PR and SD/PD groups, respectively (P>0.05). Neither the PITX1 nor the p53 LIs were a statistically significant indicator of the prognosis. PITX1 is a candidate tumor suppressor gene and a possible predictive biomarker of chemosensitivity of human HNSCC.

19.
Anal Sci ; 32(2): 153-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26860558

RESUMO

Human plasma arginine vasopressin (AVP) levels serve as a clinically relevant marker of diabetes and related syndromes. We developed a highly sensitive method for measuring human plasma AVP using high-performance liquid chromatography tandem mass spectrometry. AVP was extracted from human plasma using a weak-cation solid-phase extraction plate, and separated on a wide-bore octadecyl reverse-phase column. AVP was quantified in ion-transition experiments utilizing a product ion (m/z 328.3) derived from its parent ion (m/z 542.8). The sensitivity was enhanced using 0.02% dichloromethane as a mobile-phase additive. The lower limit of quantitation was 0.200 pmol/L. The extraction recovery ranged from 70.2 ± 7.2 to 73.3 ± 6.2% (mean ± SD), and the matrix effect ranged from 1.1 - 1.9%. Quality-testing samples revealed interday/intraday accuracy and precision ranging over 0.9 - 3% and -0.3 - 2%, respectively, which included the endogenous baseline. Our results correlated well with radioimmunoassay results using 22 human volunteer plasma samples.


Assuntos
Arginina Vasopressina/análise , Arginina Vasopressina/sangue , Cromatografia Líquida de Alta Pressão/métodos , Radioimunoensaio/métodos , Espectrometria de Massas em Tandem/métodos , Calibragem , Cromatografia por Troca Iônica/métodos , Eletrodos , Humanos , Cloreto de Metileno/química , Controle de Qualidade , Reprodutibilidade dos Testes
20.
Sci Rep ; 6: 20690, 2016 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-26868975

RESUMO

Long noncoding RNAs (lncRNAs) have been implicated in many biological processes through epigenetic mechanisms. We previously reported that KCNQ1OT1, an imprinted antisense lncRNA in the human KCNQ1 locus on chromosome 11p15.5, is involved in cis-limited silencing within an imprinted KCNQ1 cluster. Furthermore, aberration of KCNQ1OT1 transcription was observed with a high frequency in colorectal cancers. However, the molecular mechanism of the transcriptional regulation and the functional role of KCNQ1OT1 in colorectal cancer remain unclear. Here, we show that the KCNQ1OT1 transcriptional level was significantly increased in human colorectal cancer cells in which ß-catenin was excessively accumulated in the nucleus. Additionally, overexpression of ß-catenin resulted in an increase in KCNQ1OT1 lncRNA-coated territory. On the other hand, knockdown of ß-catenin resulted in significant decrease of KCNQ1OT1 lncRNA-coated territory and an increase in the mRNA expression of the SLC22A18 and PHLDA2 genes that are regulated by KCNQ1OT1. We showed that ß-catenin can promote KCNQ1OT1 transcription through direct binding to the KCNQ1OT1 promoter. Our evidence indicates that ß-catenin signaling may contribute to development of colorectal cancer by functioning as a novel lncRNA regulatory factor via direct targeting of KCNQ1OT1.


Assuntos
Regulação Neoplásica da Expressão Gênica , RNA Longo não Codificante/genética , beta Catenina/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Neoplasias Colorretais/genética , Regulação para Baixo/genética , Células HEK293 , Humanos , Proteínas Nucleares/genética , Proteínas de Transporte de Cátions Orgânicos/genética , Canais de Potássio de Abertura Dependente da Tensão da Membrana/genética , Regiões Promotoras Genéticas , Ligação Proteica/genética , Transcrição Gênica
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