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1.
Sci Rep ; 14(1): 6738, 2024 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-38509125

RESUMO

Hypoxia-Inducible Factor-1α (HIF-1α) has presented a new direction for ischemic preconditioning of surgical flaps to promote their survival. In a previous study, we demonstrated the effectiveness of HIF-1a DNA plasmids in this application. In this study, to avoid complications associated with plasmid use, we sought to express HIF-1α through mRNA transfection and determine its biological activity by measuring the upregulation of downstream angiogenic genes. We transfected six different HIF-1a mRNAs-one predominant, three variant, and two novel mutant isoforms-into primary human dermal fibroblasts using Lipofectamine, and assessed mRNA levels using RT-qPCR. At all time points examined after transfection (3, 6, and 10 h), the levels of HIF-1α transcript were significantly higher in all HIF-1α transfected cells relative to the control (all p < 0.05, unpaired Student's T-test). Importantly, the expression of HIF-1α transcription response genes (VEGF, ANG-1, PGF, FLT1, and EDN1) was significantly higher in the cells transfected with all isoforms than with the control at six and/or ten hours post-transfection. All isoforms were transfected successfully into human fibroblast cells, resulting in the rapid upregulation of all five downstream angiogenic targets tested. These findings support the potential use of HIF-1α mRNA for protecting ischemic dermal flaps.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia , Fator A de Crescimento do Endotélio Vascular , Humanos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , RNA Mensageiro/metabolismo , Transfecção , Peptídeos e Proteínas de Sinalização Intercelular/genética , Isoformas de Proteínas/genética
3.
Adv Healthc Mater ; 12(26): e2300879, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37335811

RESUMO

Extracellular vesicles (EVs) derived from mesenchymal stem/stromal cells (MSCs) have recently been explored in clinical trials for treatment of diseases with complex pathophysiologies. However, production of MSC EVs is currently hampered by donor-specific characteristics and limited ex vivo expansion capabilities before decreased potency, thus restricting their potential as a scalable and reproducible therapeutic. Induced pluripotent stem cells (iPSCs) represent a self-renewing source for obtaining differentiated iPSC-derived MSCs (iMSCs), circumventing both scalability and donor variability concerns for therapeutic EV production. Thus, it is initially sought to evaluate the therapeutic potential of iMSC EVs. Interestingly, while utilizing undifferentiated iPSC EVs as a control, it is found that their vascularization bioactivity is similar and their anti-inflammatory bioactivity is superior to donor-matched iMSC EVs in cell-based assays. To supplement this initial in vitro bioactivity screen, a diabetic wound healing mouse model where both the pro-vascularization and anti-inflammatory activity of these EVs would be beneficial is employed. In this in vivo model, iPSC EVs more effectively mediate inflammation resolution within the wound bed. Combined with the lack of additional differentiation steps required for iMSC generation, these results support the use of undifferentiated iPSCs as a source for therapeutic EV production with respect to both scalability and efficacy.


Assuntos
Diabetes Mellitus , Vesículas Extracelulares , Células-Tronco Pluripotentes Induzidas , Camundongos , Animais , Diferenciação Celular/fisiologia , Anti-Inflamatórios , Cicatrização
4.
bioRxiv ; 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36993554

RESUMO

Extracellular vesicles (EVs) derived from mesenchymal stem/stromal cells (MSCs) have recently been widely explored in clinical trials for treatment of diseases with complex pathophysiology. However, production of MSC EVs is currently hampered by donor-specific characteristics and limited ex vivo expansion capabilities before decreased potency, thus restricting their potential as a scalable and reproducible therapeutic. Induced pluripotent stem cells (iPSCs) represent a self-renewing source for obtaining differentiated iPSC-derived MSCs (iMSCs), circumventing both scalability and donor variability concerns for therapeutic EV production. Thus, we initially sought to evaluate the therapeutic potential of iMSC EVs. Interestingly, while utilizing undifferentiated iPSC EVs as a control, we found that their vascularization bioactivity was similar and their anti-inflammatory bioactivity was superior to donor-matched iMSC EVs in cell-based assays. To supplement this initial in vitro bioactivity screen, we employed a diabetic wound healing mouse model where both the pro-vascularization and anti-inflammatory activity of these EVs would be beneficial. In this in vivo model, iPSC EVs more effectively mediated inflammation resolution within the wound bed. Combined with the lack of additional differentiation steps required for iMSC generation, these results support the use of undifferentiated iPSCs as a source for therapeutic EV production with respect to both scalability and efficacy.

5.
Allergy Rhinol (Providence) ; 12: 21526567211049744, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34659871

RESUMO

INTRODUCTION: Different subtypes of vaccines have been developed to help protect populations from COVID-19. Currently, three vaccines have been authorized by the United States Food and Drug Administration for emergency use to combat the COVID-19 pandemic. With COVID-19 vaccination rates increasing, it is important to know whether immunodeficient patients have the capacity to mount an immune response with the available vaccines. CASE REPORT: A 78-year-old female with Common Variable Immunodeficiency and anti-IgA antibodies who is naïve to IVIgG treatment responded positively to a COVID-19 mRNA vaccine. Successful seroconversion was proved by having positive COVID-19 spike protein IgG antibodies weeks after the vaccination. Her recent IgG, IgA, and IgM levels were all significantly reduced. Previously, she had no response to the polysaccharide pneumococcal vaccine, but did maintain titers afterTdap vaccination. DISCUSSION: Immunodeficient patients are a susceptible population during a pandemic. Unfortunately, there is a paucity of research on the infectivity, vaccination, and outcome of these patients during the COVID-19 outbreak. Our patient with CVID was able to respond to protein/toxoid vaccines, but did not respond to polysaccharide pneumococcal vaccine. After inoculation with an mRNA COVID-19 vaccine she was able to create COVID-19 spike protein IgG antibodies. CONCLUSION: We present a case of successful vaccination to COVID-19 by an mRNA vaccine in an IVIgG naïve CVID patient.

6.
Cancers (Basel) ; 13(7)2021 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-33916875

RESUMO

Barrett's esophagus (BE) is a precursor to esophageal adenocarcinoma (EAC). Recently, long noncoding RNAs (lncRNAs) have been identified as key regulators of biological pathways. However, involvement of lncRNAs in the development of BE and EAC has not been well-studied. The aims of the current study were: (1) to study involvement of the lncRNA, miR205HG, in the development of BE and EAC; (2) to clarify the role of miR205HG in in vitro and in vivo experiments; and (3) to investigate the mechanism of miR205HG involving the Hedgehog (Hh) signaling pathway. These experiments revealed that miR205HG was downregulated in EAC vs. normal esophageal epithelia (NE) as well as in EAC cell lines, and its forced overexpression inhibited EAC cell proliferation and cell cycle progression in vitro. Similarly, overexpression of miR205HG inhibited xenograft tumor growth in mice In vivo. Finally, we show that one mechanism of action of miR205HG involves the Hh signaling pathway: miR205HG and Hh expression levels were inversely correlated in both EAC (r = -0.73) and BE (r = -0.83) tissues, and in vitro studies revealed details of Hh signaling inhibition induced by miR205HG. In conclusion, these findings establish that lncRNA miR205HG functions as a tumor suppressor in the development of BE and EAC, at least in part through its effect on the Hh signaling pathway.

7.
Gene Ther ; 28(6): 319-328, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33024315

RESUMO

Ischemic necrosis of surgical flaps after reconstruction is a major clinical problem. Hypoxia-inducible factor-1α (HIF-1α) is considered the master regulator of the adaptive response to hypoxia. Among its many properties, it regulates the expression of genes encoding angiogenic growth factors, which have a short half-life in vivo. To achieve a continuous application of the therapeutic, we utilized DNA plasmid delivery. Transcription of the DNA plasmid confirmed by qRT-PCR showed significantly increased mRNA for HIF-1α in the transfected tissue compared to saline control tissue. Rats were preconditioned by injecting with either HIF-1α DNA plasmid or saline intradermally in the designated flap region on each flank. Seven days after preconditioning, each rat had two isolated pedicle flaps raised with a sterile silicone sheet implanted between the skin flap and muscle layer. The flaps preconditioned with HIF-1α DNA plasmid had significantly less necrotic area. Angiogenesis measured by CD31 staining showed a significant increase in the number of vessels per high powered field in the HIF-1α group (p < 0.05). Our findings offer a potential therapeutic strategy for significantly promoting the viability of surgical pedicle flaps by ischemic preconditioning with HIF-1α DNA plasmid.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia , Retalhos Cirúrgicos , Animais , DNA , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Plasmídeos/genética , Ratos , Ratos Sprague-Dawley , Sobrevivência de Tecidos
8.
Gastrointest Tumors ; 6(1-2): 11-27, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31602373

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is now the second-highest cause of cancer death worldwide. Recent studies have discovered a wide range of somatic mutations in HCC. These mutations involve various vital signaling pathways such as: Wnt/ß-Catenin, p53, telome-rase reverse transcriptase (TERT), chromatin remodeling, RAS/MAPK signaling, and oxidative stress. However, fusion transcripts have not been broadly explored in HCC. METHODS: To identify novel fusion transcripts in HCC, in the first phase of our study, we performed targeted RNA sequencing (in HCC and paired non-HCC tissues) on 6 patients with a diagnosis of HCC undergoing liver transplantation. RESULTS: As a result of these studies, we discovered the novel fusion transcript, VTI1A-CFAP46. In the second phase of our study, we measured the expression of wild-type VTI1A in 21 HCC specimens, which showed that 10 of 21 exhibited upregulation of wild-type VTI1A in their tumors. VTI1A (Vesicle Transport via Interaction with t-SNARE homolog 1A) is a member of the Soluble N-ethylmaleimide-Sensitive Factor (NSF) attachment protein receptor (SNARE) gene family, which is essential for membrane trafficking and function in endocytosis, autophagy, and Golgi transport. Notably, it is known that autophagy is involved in HCC. CONCLUSIONS: The link between novel fusion transcript VTI1A-CFAP46 and autophagy as a potential therapeutic target in HCC patients deserves further investigation. Moreover, this study shows that fusion transcripts are worthy of additional exploration in HCC.

9.
Lab Invest ; 99(10): 1442-1453, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31217510

RESUMO

MicroRNAs (miRs) are post-transcriptional regulators involved in the initiation and progression of many tumors. Recently, naturally occurring circular RNAs (circRNAs) have been described in eukaryotic cells:;they comprise a new class of gene regulators. Naturally occurring circular miR sponges, which induce miR loss-of-function, can prevent endogenous onco-miRs from binding to their cognate mRNA targets. These findings suggest that synthetic (artificial) circular RNAs could be constructed as therapeutic molecular sponges to suppress harmful onco-miRs. Using enzymatic ligation, we designed and constructed a circular RNA containing both miR-21 and miR-93 binding sites. The synthetic circular sponge was resistant to digestion with RNase R. Luciferase assays and functional experiments showed that the circular multi-miR sponge was more stable than its linear counterpart. Moreover, endogenous miR-21 and miR-93 were inhibited by the circular sponge. In addition, the synthetic sponge significantly suppressed cellular proliferation and migration while promoting apoptosis in esophageal carcinoma cells. Finally, in a murine xenograft model, the circular sponge significantly inhibited tumor growth in vivo. Taken together, these findings establish that the design and construction of efficient artificial miR sponges represent a novel strategy to achieve miR loss-of-function in molecular cancer therapeutics.


Assuntos
Carcinoma/tratamento farmacológico , Neoplasias Esofágicas/tratamento farmacológico , MicroRNAs/antagonistas & inibidores , RNA Circular/uso terapêutico , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos Nus , RNA Circular/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Clin Cancer Res ; 25(7): 2127-2135, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30670490

RESUMO

PURPOSE: Barrett's esophagus is the only known precursor of esophageal adenocarcinoma (EAC). Although endoscopy and biopsy are standard methods for Barrett's esophagus diagnosis, their high cost and risk limit their use as a screening modality. Here, we sought to develop a Barrett's esophagus detection method based on methylation status in cytology samples captured by EsophaCap using a streamlined sensitive technique, methylation on beads (MOB). EXPERIMENTAL DESIGN: We conducted a prospective cohort study on 80 patients (52 in the training set; 28 in the test set). We used MOB to extract and bisulfite-convert DNA, followed by quantitative methylation-specific PCR to assess methylation levels of 8 previously selected candidate markers. Lasso regression was applied to establish a prediction model in the training set, which was then tested on the independent test set. RESULTS: In the training set, five of eight candidate methylation biomarkers (p16, HPP1, NELL1, TAC1, and AKAP12) were significantly higher in Barrett's esophagus patients than in controls. We built a four-biomarker-plus-age lasso regression model for Barrett's esophagus diagnosis. The AUC was 0.894, with sensitivity 94.4% [95% confidence interval (CI), 71%-99%] and specificity 62.2% (95% CI, 44.6%-77.3%) in the training set. This model also performed with high accuracy for Barrett's esophagus diagnosis in an independent test set: AUC = 0.929 (P < 0.001; 95% CI, 0.810%-1%), with sensitivity=78.6% (95% CI, 48.8%-94.3%) and specificity = 92.8% (95% CI, 64.1%-99.6%). CONCLUSIONS: EsophaCap, in combination with an epigenetic biomarker panel and the MOB method, is a promising, well-tolerated, low-cost esophageal sampling strategy for Barrett's esophagus diagnosis. This approach merits further prospective studies in larger populations.


Assuntos
Esôfago de Barrett/diagnóstico , Esôfago de Barrett/etiologia , Biomarcadores , Citodiagnóstico , Metilação de DNA , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Citodiagnóstico/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Mol Ther Nucleic Acids ; 13: 312-321, 2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30326427

RESUMO

MicroRNA (miR) sponges containing miR binding sequences constitute a potentially powerful molecular therapeutic strategy. Recently, naturally occurring circular RNAs (circRNAs) were shown to function as efficient miR sponges in cancer cells. We hypothesized that synthetic circRNA sponges could achieve therapeutic loss-of-function targeted against specific miRs. Linear RNA molecules containing miR-21 binding sites were transcribed in vitro; after dephosphorylation and phosphorylation, circularization was achieved using 5'-3' end-ligation by T4 RNA ligase 1. circRNA stability was assessed using RNase R and fetal bovine serum. Competitive inhibition of miR-21 activity by a synthetic circRNA sponge was assessed using luciferase reporter, cell proliferation, and cell apoptosis assays in three gastric cancer cell lines. circRNA effects on downstream proteins were also delineated by Tandem Mass Tag (TMT) labeling (data available via ProteomeXchange identifier PRIDE: PXD008584), followed by western blotting. We conclude that artificial circRNA sponges resistant to nuclease digestion can be synthesized using simple enzymatic ligation steps. These sponges inhibit cancer cell proliferation and suppress the activity of miR-21 on downstream protein targets, including the cancer protein DAXX. In summary, synthetic circRNA sponges represent a simple, effective, convenient strategy for achieving targeted loss of miR function in vitro, with potential future therapeutic application in human patients.

12.
Cancer Lett ; 436: 109-118, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30144514

RESUMO

Primary organoid cultures generated from patient biopsies comprise a novel improved platform for disease modeling, being genetically stable and closely recapitulating in vivo scenarios. Barrett esophagus (BE) is the major risk factor for esophageal adenocarcinoma. There has been a dearth of long-term in vitro expansion models of BE neoplastic transformation. We generated a long-term virus-free organoid expansion model of BE neoplasia from patient biopsies. Both wild-type and paired APC-knockout (APCKO) BE organoids genome-edited by CRISPR-Cas9 showed characteristic goblet cell differentiation. Autonomous Wnt activation was confirmed in APCKO organoids by overexpression of Wnt target genes and nuclear-translocated ß-catenin expression after withdrawal of Wnt-3A and R-spondin-1. Wnt-activated organoids demonstrated histologic atypia, higher proliferative and replicative activity, reduced apoptosis, and prolonged culturability. Wnt-activated organoids also showed sustained protrusive migration ability accompanied by disrupted basement membrane reorganization and integrity. This CRISPR-Cas9 editing human-derived organoid model recapitulates the critical role of aberrant Wnt/ß-catenin signaling activation in BE neoplastic transformation. This system can be used to study other 'driver' pathway alterations in BE-associated neoplasia, avoiding signaling noise present in immortalized or cancer-derived cell lines.


Assuntos
Esôfago de Barrett/metabolismo , Sistemas CRISPR-Cas , Transformação Celular Neoplásica/genética , Edição de Genes/métodos , Via de Sinalização Wnt/genética , beta Catenina/genética , Proteína da Polipose Adenomatosa do Colo/genética , Proteína da Polipose Adenomatosa do Colo/metabolismo , Apoptose/genética , Esôfago de Barrett/patologia , Diferenciação Celular/genética , Movimento Celular/genética , Proliferação de Células/genética , Técnicas de Inativação de Genes , Humanos , Modelos Genéticos , Organoides/metabolismo , Organoides/patologia
13.
Neoplasia ; 19(11): 941-949, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28968550

RESUMO

There have been no reports describing the effects of cancer cell-derived extracellular vesicles (EVs) on three-dimensional organoids. In this study, we delineated the proneoplastic effects of esophageal adenocarcinoma (EAC)-derived EVs on gastric organoids (gastroids) and elucidated molecular mechanisms underlying these effects. EVs were identified using PKH-67 staining. Morphologic changes, Ki-67 immunochemistry, cell viability, growth rates, and expression levels of miR-25 and miR-210, as well as of their target mRNAs, were determined in gastroids co-cultured with EAC-derived extracellular vesicles (c-EVs). C-EVs were efficiently taken up by gastroids. Notably, c-EV-treated gastroids were more crowded, compact, and multilayered and contained smaller lumens than did those cultured in organoid medium alone or in EAC-conditioned medium that had been depleted of EVs. Moreover, c-EV-treated gastroids manifested increased proliferation and cellular viability relative to medium-only or EV-depleted controls. Expression levels of miR-25 and miR-210 were significantly higher, and those of PTEN and AIFM3 significantly lower, in c-EV-treated versus medium-only or EV-depleted control groups. Inhibitors of miR-25 and miR-210 reversed the increased cell proliferation induced by c-exosomes in co-cultured gastroids by lowering miR-25 and miR-210 levels. In conclusion, we have constructed a novel model system featuring the co-culture of c-EVs with three-dimensional gastroids. Using this model, we discovered that cancer-derived EVs induce a neoplastic phenotype in gastroids. These changes are due, at least in part, to EV transfer of miR-25 and miR-210.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias Esofágicas/metabolismo , Vesículas Extracelulares/metabolismo , Mucosa Gástrica/metabolismo , MicroRNAs/metabolismo , Organoides/metabolismo , Fenótipo , Adenocarcinoma/genética , Adenocarcinoma/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/fisiologia , Transformação Celular Neoplásica , Técnicas de Cocultura , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Vesículas Extracelulares/genética , Vesículas Extracelulares/patologia , Mucosa Gástrica/patologia , Humanos , MicroRNAs/administração & dosagem , MicroRNAs/genética , Organoides/patologia
14.
Cancer ; 123(20): 3916-3924, 2017 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-28640357

RESUMO

BACKGROUND: Studies of chromosomal rearrangements and fusion transcripts have elucidated mechanisms of tumorigenesis and led to targeted cancer therapies. This study was aimed at identifying novel fusion transcripts in esophageal adenocarcinoma (EAC). METHODS: To identify new fusion transcripts associated with EAC, targeted RNA sequencing and polymerase chain reaction (PCR) verification were performed in 40 EACs and matched nonmalignant specimens from the same patients. Genomic PCR and Sanger sequencing were performed to find the breakpoint of fusion genes. RESULTS: Five novel in-frame fusion transcripts were identified and verified in 40 EACs and in a validation cohort of 15 additional EACs (55 patients in all): fibroblast growth factor receptor 2 (FGFR2)-GRB2-associated binding protein 2 (GAB2) in 2 of 55 or 3.6%, Niemann-Pick C1 (NPC1)-maternal embryonic leucine zipper kinase (MELK) in 2 of 55 or 3.6%, ubiquitin-specific peptidase 54 (USP54)-calcium/calmodulin dependent protein kinase II γ (CAMK2G) in 2 of 55 or 3.6%, megakaryoblastic leukemia (translocation) 1 (MKL1)-fibulin 1 (FBLN1) in 1 of 55 or 1.8%, and CCR4-NOT transcription complex subunit 2 (CNOT2)-chromosome 12 open reading frame 49 (C12orf49) in 1 of 55 or 1.8%. A genomic analysis indicated that NPC1-MELK arose from a complex interchromosomal translocation event involving chromosomes 18, 3, and 9 with 3 rearrangement points, and this was consistent with chromoplexy. CONCLUSIONS: These data indicate that fusion transcripts occur at a stable frequency in EAC. Furthermore, our results indicate that chromoplexy is an underlying mechanism that generates fusion transcripts in EAC. These and other fusion transcripts merit further study as diagnostic markers and potential therapeutic targets in EAC. Cancer 2017;123:3916-24. © 2017 American Cancer Society.


Assuntos
Adenocarcinoma/genética , Neoplasias Esofágicas/genética , Rearranjo Gênico/genética , Proteínas Mutantes Quiméricas/genética , RNA Mensageiro/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas de Ligação ao Cálcio/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Proteínas de Transporte/genética , Estudos de Casos e Controles , Linhagem Celular Tumoral , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Glicoproteínas de Membrana/genética , Pessoa de Meia-Idade , Proteína C1 de Niemann-Pick , Proteínas Serina-Treonina Quinases/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de RNA , Transativadores/genética , Proteases Específicas de Ubiquitina/genética
15.
Gastroenterology ; 153(1): 27-34, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28528706

RESUMO

For many years, only a small fraction of the human genome was believed to regulate cell function and development. This protein-coding portion composed only 1% to 2% of 3 billion human DNA base pairs-the remaining sequence was classified as junk DNA. Subsequent research has revealed that most of the genome is transcribed into a broad array of noncoding RNAs, ranging in size from microRNA (20-23 nucleotides) to long noncoding RNA (lncRNA, more than 200 nucleotides). These noncoding RNA classes have been shown to use diverse molecular mechanisms to control gene expression and organ system development. As anticipated, alterations in this large control system can contribute to disease pathogenesis and carcinogenesis. We review the involvement of noncoding RNAs, lncRNAs in particular, in development of Barrett's esophagus and esophageal carcinoma.


Assuntos
Esôfago de Barrett/genética , Neoplasias Esofágicas/genética , Regulação Neoplásica da Expressão Gênica , Lesões Pré-Cancerosas/genética , RNA Longo não Codificante/genética , Metilação de DNA , Humanos
16.
Cancer ; 123(9): 1507-1515, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28081303

RESUMO

BACKGROUND: Novel fusion transcripts (FTs) caused by chromosomal rearrangement are common factors in the development of cancers. In the current study, the authors used massively parallel RNA sequencing to identify new FTs in colon cancers. METHODS: RNA sequencing (RNA-Seq) and TopHat-Fusion were used to identify new FTs in colon cancers. The authors then investigated whether the novel FT nuclear receptor subfamily 5, group A, member 2 (NR5A2)-Kelch-like family member 29 FT (KLHL29FT) was transcribed from a genomic chromosomal rearrangement. Next, the expression of NR5A2-KLHL29FT was measured by quantitative real-time polymerase chain reaction in colon cancers and matched corresponding normal epithelia. RESULTS: The authors identified the FT NR5A2-KLHL29FT in normal and cancerous epithelia. While investigating this transcript, it was unexpectedly found that it was due to an uncharacterized polymorphic germline insertion of the NR5A2 sequence from chromosome 1 into the KLHL29 locus at chromosome 2, rather than a chromosomal rearrangement. This germline insertion, which occurred at a population frequency of 0.40, appeared to bear no relationship to cancer development. Moreover, expression of NR5A2-KLHL29FT was validated in RNA specimens from samples with insertions of NR5A2 at the KLHL29 gene locus, but not from samples without this insertion. It is interesting to note that NR5A2-KLH29FT expression levels were significantly lower in colon cancers than in matched normal colonic epithelia (P =.029), suggesting the potential participation of NR5A2-KLHL29FT in the origin or progression of this tumor type. CONCLUSIONS: NR5A2-KLHL29FT was generated from a polymorphism insertion of the NR5A2 sequence into the KLHL29 locus. NR5A2-KLHL29FT may influence the origin or progression of colon cancer. Moreover, researchers should be aware that similar FTs may occur due to transchromosomal insertions that are not correctly annotated in genome databases, especially with current assembly algorithms. Cancer 2017;123:1507-1515. © 2017 American Cancer Society.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Colo/metabolismo , Neoplasias do Colo/genética , Mutagênese Insercional , Proteínas de Fusão Oncogênica/genética , RNA Mensageiro/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Neoplasias do Colo/metabolismo , Mutação em Linhagem Germinativa , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de RNA
17.
PLoS One ; 10(6): e0128152, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26030880

RESUMO

Radioisotopes that emit electrons (beta particles), such as radioiodine, can effectively kill target cells, including cancer cells. Aqueous 32P[PO4] is a pure beta-emitter that has been used for several decades to treat non-malignant human myeloproliferative diseases. 32P[PO4] was directly compared to a more powerful pure beta-emitter, the clinically important 90Y isotope. In vitro, 32P[PO4] was more effective at killing cells than was the more powerful isotope 90Y (P ≤ 0.001) and also caused substantially more double-stranded DNA breaks than did 90Y. In vivo, a single low-dose intravenous dose of aqueous elemental 32P significantly inhibited tumor growth in the syngeneic murine cancer model (P ≤ 0.001). This effect is exerted by direct incorporation into nascent DNA chains, resulting in double-stranded breakage, a unique mechanism not duplicatable by other, more powerful electron-emitting radioisotopes. 32P[PO4] should be considered for human clinical trials as a potential novel anti-cancer drug.


Assuntos
Quebras de DNA de Cadeia Dupla/efeitos da radiação , Radioisótopos de Fósforo/uso terapêutico , Animais , Partículas beta/uso terapêutico , Proliferação de Células/efeitos da radiação , Células HeLa , Humanos , Injeções Intravenosas , Camundongos , Modelos Moleculares , Conformação de Ácido Nucleico , Radioisótopos de Fósforo/administração & dosagem , Radioisótopos de Fósforo/química , Fatores de Tempo , Água/química
18.
Gut ; 63(6): 881-90, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24000294

RESUMO

OBJECTIVES: Long non-coding RNAs (lncRNA) have been shown to play important roles in the development and progression of cancer. However, functional lncRNAs and their downstream mechanisms are largely unknown in the molecular pathogenesis of oesophageal adenocarcinoma (EAC) and its progression. DESIGN: lncRNAs that are abnormally upregulated in EACs were identified by RNA-sequencing analysis, followed by quantitative RT-PCR (qRTPCR) validation using tissues from 25 EAC patients. Cell biological assays in combination with small interfering RNA-mediated knockdown were performed in order to probe the functional relevance of these lncRNAs. RESULTS: We discovered that a lncRNA, HNF1A-AS1, is markedly upregulated in human primary EACs relative to their corresponding normal oesophageal tissues (mean fold change 10.6, p<0.01). We further discovered that HNF1A-AS1 knockdown significantly inhibited cell proliferation and anchorage-independent growth, suppressed S-phase entry, and inhibited cell migration and invasion in multiple in vitro EAC models (p<0.05). A gene ontological analysis revealed that HNF1A-AS1 knockdown preferentially affected genes that are linked to assembly of chromatin and the nucleosome, a mechanism essential to cell cycle progression. The well known cancer-related lncRNA, H19, was the gene most markedly inhibited by HNF1A-AS1 knockdown. Consistent to this finding, there was a significant positive correlation between HNF1A-AS1 and H19 expression in primary EACs (p<0.01). CONCLUSIONS: We have discovered abnormal upregulation of a lncRNA, HNF1A-AS1, in human EAC. Our findings suggest that dysregulation of HNF1A-AS1 participates in oesophageal tumorigenesis, and that this participation may be mediated, at least in part, by modulation of chromatin and nucleosome assembly as well as by H19 induction.


Assuntos
Adenocarcinoma/genética , Neoplasias Esofágicas/genética , Expressão Gênica , RNA Longo não Codificante/genética , RNA Longo não Codificante/fisiologia , Adenocarcinoma/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Neoplasias Esofágicas/patologia , Técnicas de Silenciamento de Genes , Humanos , RNA Interferente Pequeno , Pontos de Checagem da Fase S do Ciclo Celular/genética , Regulação para Cima
19.
Inflamm Bowel Dis ; 19(3): 471-80, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23399735

RESUMO

BACKGROUND: The development of colon cancer represents a major complication in patients with inflammatory bowel disease (IBD). The importance of microRNAs (miRs) in carcinogenesis is becoming clearer because miRs have been implicated in the regulation of cancer-related cellular processes to include apoptosis, differentiation, cell cycle progression, and immune function. In the current study, we sought to identify miR dysregulation specific to progression along the normal-inflammation-cancer axis in colonic specimens from patients with IBD. METHODS: MiR microarrays and quantitative reverse transcription PCR were used to detect and confirm dysregulated miRs. Receiver operating characteristic curve analysis was applied to evaluate the potential use of miR-224 as a neoplastic disease marker in IBD. For miR-224 target messenger RNA (mRNA) identification, mRNA microarrays were employed in combination with bioinformatic analyses, Western blotting, and luciferase activity measurements. RESULTS: We identified 30 miRs that were differentially expressed between chronically inflamed mucosae and cancers arising from IBD tissues. MiR-224 levels increased successively at each stage of IBD progression and accurately discriminated cancers from normal or chronically inflamed IBD tissues. Moreover, mRNA arrays combined with bioinformatic analyses suggested the participation of miR-224 in cell cycle regulation. Subsequently, cell cycle experiments indicated that miR-224 regulates the G1-S checkpoint. Finally, in silico prediction analyses, confirmed by Western blotting and luciferase assays, identified p21 as a specific direct mRNA target of miR-224. CONCLUSIONS: These findings reveal miR dysregulation specific to IBD-associated colorectal carcinoma. MiR-224 is overexpressed in IBD cancers and targets p21, a key cell cycle regulator. Moreover, these results establish the participation of miR-224 in IBD carcinogenesis.


Assuntos
Neoplasias do Colo/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Regulação Neoplásica da Expressão Gênica , Doenças Inflamatórias Intestinais/complicações , MicroRNAs/metabolismo , Biomarcadores/metabolismo , Western Blotting , Estudos de Casos e Controles , Estudos de Coortes , Neoplasias do Colo/etiologia , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Progressão da Doença , Citometria de Fluxo , Marcadores Genéticos , Humanos , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Curva ROC , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
Gastroenterology ; 144(5): 956-966.e4, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23333711

RESUMO

BACKGROUND & AIMS: Alterations in methylation of protein-coding genes are associated with Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC). Dysregulation of noncoding RNAs occurs during carcinogenesis but has never been studied in BE or EAC. We applied high-resolution methylome analysis to identify changes at genomic regions that encode noncoding RNAs in BE and EAC. METHODS: We analyzed methylation of 1.8 million CpG sites using massively parallel sequencing-based HELP tagging in matched EAC, BE, and normal esophageal tissues. We also analyzed human EAC (OE33, SKGT4, and FLO-1) and normal (HEEpic) esophageal cells. RESULTS: BE and EAC exhibited genome-wide hypomethylation, significantly affecting intragenic and repetitive genomic elements as well as noncoding regions. These methylation changes targeted small and long noncoding regions, discriminating normal from matched BE or EAC tissues. One long noncoding RNA, AFAP1-AS1, was extremely hypomethylated and overexpressed in BE and EAC tissues and EAC cells. Its silencing by small interfering RNA inhibited proliferation and colony-forming ability, induced apoptosis, and reduced EAC cell migration and invasion without altering the expression of its protein-coding counterpart, AFAP1. CONCLUSIONS: BE and EAC exhibit reduced methylation that includes noncoding regions. Methylation of the long noncoding RNA AFAP1-AS1 is reduced in BE and EAC, and its expression inhibits cancer-related biologic functions of EAC cells.


Assuntos
Adenocarcinoma/genética , Esôfago de Barrett/genética , DNA de Neoplasias/genética , Neoplasias Esofágicas/genética , Regulação Neoplásica da Expressão Gênica , Proteínas dos Microfilamentos/genética , RNA Longo não Codificante/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Esôfago de Barrett/metabolismo , Esôfago de Barrett/patologia , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/genética , Metilação de DNA , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Humanos , Proteínas dos Microfilamentos/metabolismo , Regiões Promotoras Genéticas , RNA Interferente Pequeno/genética
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