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1.
Breast Cancer Res ; 21(1): 89, 2019 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-31391072

RESUMO

BACKGROUND: Understanding the molecular alterations associated with breast cancer (BC) progression may lead to more effective strategies for both prevention and management. The current model of BC progression suggests a linear, multistep process from normal epithelial to atypical ductal hyperplasia (ADH), to ductal carcinoma in situ (DCIS), and then invasive ductal carcinoma (IDC). Up to 20% ADH and 40% DCIS lesions progress to invasive BC if left untreated. Deciphering the molecular mechanisms during BC progression is therefore crucial to prevent over- or under-treatment. Our previous work demonstrated that miR-671-5p serves as a tumor suppressor by targeting Forkhead box protein M1 (FOXM1)-mediated epithelial-to-mesenchymal transition (EMT) in BC. Here, we aim to explore the role of miR-671-5p in the progression of BC oncogenic transformation and treatment. METHODS: The 21T series cell lines, which were originally derived from the same patient with metastatic BC, including normal epithelia (H16N2), ADH (21PT), primary DCIS (21NT), and cells derived from pleural effusion of lung metastasis (21MT), and human BC specimens were used. Microdissection, miRNA transfection, dual-luciferase, radio- and chemosensitivity, and host-cell reactivation (HCR) assays were performed. RESULTS: Expression of miR-671-5p displays a gradual dynamic decrease from ADH, to DCIS, and to IDC. Interestingly, the decreased expression of miR-671-5p detected in ADH coexisted with advanced lesions, such as DCIS and/or IDC (cADH), but not in simple ADH (sADH). Ectopic transfection of miR-671-5p significantly inhibited cell proliferation in 21NT (DCIS) and 21MT (IDC), but not in H16N2 (normal) and 21PT (ADH) cell lines. At the same time, the effect exhibited in time- and dose-dependent manner. Interestingly, miR-671-5p significantly suppressed invasion in 21PT, 21NT, and 21MT cell lines. Furthermore, miR-671-5p suppressed FOXM1-mediated EMT in all 21T cell lines. In addition, miR-671-5p sensitizes these cell lines to UV and chemotherapeutic exposure by reducing the DNA repair capability. CONCLUSIONS: miR-671-5p displays a dynamic decrease expression during the oncogenic transition of BC by suppressing FOXM1-mediated EMT and DNA repair. Therefore, miR-671-5p may serve as a novel biomarker for early BC detection as well as a therapeutic target for BC management.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Transformação Celular Neoplásica/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Tolerância a Radiação/genética , Regiões 3' não Traduzidas , Neoplasias da Mama/terapia , Linhagem Celular Tumoral , Dano ao DNA , Progressão da Doença , Transição Epitelial-Mesenquimal/genética , Feminino , Proteína Forkhead Box M1/genética , Genes Reporter , Humanos , Modelos Biológicos , Interferência de RNA
2.
Breast Cancer Res ; 16(5): 435, 2014 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-25228385

RESUMO

INTRODUCTION: Triple-negative breast cancer (TNBC) represents 15 to 20% of all types of breast cancer; however, it accounts for a large number of metastatic cases and deaths, and there is still no effective treatment. The deregulation of microRNAs (miRNAs) in breast cancer has been widely reported. We previously identified that miR-638 was one of the most deregulated miRNAs in breast cancer progression. Bioinformatics analysis revealed that miR-638 directly targets BRCA1. The aim of this study was to investigate the role of miR-638 in breast cancer prognosis and treatment. METHODS: Formalin-fixed, paraffin-embedded (FFPE) breast cancer samples were microdissected into normal epithelial and invasive ductal carcinoma (IDC) cells, and total RNA was isolated. Several breast cancer cell lines were used for the functional analysis. miR-638 target genes were identified by TARGETSCAN-VERT 6.2 and miRanda. The expression of miR-638 and its target genes was analyzed by real-time qRT-PCR and Western blotting. Dual-luciferase reporter assay was employed to confirm the specificity of miR-638 target genes. The biological function of miR-638 was analyzed by MTT chemosensitivity, matrigel invasion and host cell reactivation assays. RESULTS: The expression of miR-638 was decreased in IDC tissue samples compared to their adjacent normal controls. The decreased miR-638 expression was more prevalent in non-TNBC compared with TNBC cases. miR-638 expression was significantly downregulated in breast cancer cell lines compared to the immortalized MCF-10A epithelial cells. BRCA1 was predicted as one of the direct targets of miR-638, which was subsequently confirmed by dual-luciferase reporter assay. Forced expression of miR-638 resulted in a significantly reduced proliferation rate as well as decreased invasive ability in TNBC cells. Furthermore, miR-638 overexpression increased sensitivity to DNA-damaging agents, ultraviolet (UV) and cisplatin, but not to 5-fluorouracil (5-FU) and epirubicin exposure in TNBC cells. Host cell reactivation assays showed that miR-638 reduced DNA repair capability in post UV/cisplatin-exposed TNBC cells. The reduced proliferation, invasive ability, and DNA repair capabilities are associated with downregulated BRCA1 expression. CONCLUSIONS: Our findings suggest that miR-638 plays an important role in TNBC progression via BRCA1 deregulation. Therefore, miR-638 might serve as a potential prognostic biomarker and therapeutic target for breast cancer.


Assuntos
Antineoplásicos/farmacologia , Proteína BRCA1/genética , Cisplatino/farmacologia , MicroRNAs/fisiologia , Neoplasias de Mama Triplo Negativas/genética , Proteína BRCA1/metabolismo , Sequência de Bases , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células , Reparo do DNA , Feminino , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica , Interferência de RNA , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Raios Ultravioleta
3.
J Virol ; 86(4): 1911-21, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22156527

RESUMO

The Wnt/ß-catenin pathway is involved in diverse cell functions governing development and disease. ß-Catenin, a central mediator of this pathway, binds to members of the TCF/LEF family of transcription factors to modulate hundreds of genes. Active Wnt/ß-catenin/TCF-4 signaling plays a significant role in repression of HIV-1 replication in multiple cell targets, including astrocytes. To determine the mechanism by which active ß-catenin/TCF-4 leads to inhibition of HIV replication, we knocked down ß-catenin or TCF/LEF members in primary astrocytes and astrocytomas transiently transfected with an HIV long terminal repeat (LTR)-luciferase reporter that contained an integrated copy of the HIV LTR-luciferase construct. Knockdown of either ß-catenin or TCF-4 induced LTR activity by 2- to 3-fold under both the episomal and integrated conditions. This knockdown also increased presence of serine 2-phosphorylated RNA polymerase II (Pol II) on the HIV LTR as well as enhanced its processivity. Knockdown of ß-catenin/TCF-4 also impacted tethering of other transcription factors on the HIV promoter. Specifically, knockdown of TCF-4 enhanced binding of C/EBPß, C/EBPδ, and NF-κB to the HIV LTR, while ß-catenin knockdown increased binding of C/EBPß and C/EBPδ but had no effect on NF-κB. Approximately 150 genes in astrocytes were impacted by ß-catenin knockdown, including genes involved in inflammation/immunity, uptake/transport, vesicular transport/exocytosis, apoptosis/cellular stress, and cytoskeleton/trafficking. These findings indicate that modulation of the ß-catenin/TCF-4 axis impacts the basal level of HIV transcription in astrocytes, which may drive low level/persistent HIV in astrocytes that can contribute to ongoing neuroinflammation, and this axis also has profound effects on astrocyte biology.


Assuntos
Astrócitos/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Infecções por HIV/metabolismo , HIV-1/genética , Fatores de Transcrição/metabolismo , Ativação Transcricional , beta Catenina/metabolismo , Astrócitos/virologia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Linhagem Celular Tumoral , Células Cultivadas , Regulação Viral da Expressão Gênica , Infecções por HIV/genética , Infecções por HIV/virologia , Repetição Terminal Longa de HIV , HIV-1/fisiologia , Humanos , Dados de Sequência Molecular , Transdução de Sinais , Fator de Transcrição 4 , Fatores de Transcrição/genética , beta Catenina/genética
4.
Surg Endosc ; 27(7): 2492-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23306619

RESUMO

BACKGROUND: After bariatric surgery, there is a significant improvement in type 2 diabetes (T2D). T2D has been linked to incretins, including glucose-dependent insulinotropic polypeptide (GIP). Analysis of bariatric surgery patients may help to understand the link between GIP and T2D. METHODS: Twenty-three morbidly obese patients underwent Roux-en-Y gastric bypass (RYGB) or gastric banding. Overall, there were 12 RYGB (5 T2D; 7 nondiabetic) patients and 11 gastric band (7 T2D; 4 nondiabetic) patients. Preoperative and postoperative blood samples were collected. Total RNA was extracted, cDNA synthesized, and real-time quantitative PCR were used to quantify gene expression. Student's t test was used for statistical analysis. RESULTS: Postoperatively, T2D resolved or improved in 83.3 % (10/12) of the diabetic patients. Six (4 RYGB, 2 bands) patients discontinued hypoglycemic medications and four (3 RYGB, 1 band) patients discontinued the majority of their hypoglycemic agents. The remaining two diabetic patients (bands) showed no improvement. Postoperative GIP gene expression increased 4.36-fold (p = 0.02) in diabetic RYGB patients, whereas diabetic band patients increased 1.4-fold (p = 0.25). All diabetic patients with either resolution or improvement of T2D, had a 3.4-fold increase (p = 0.01) but nonresponders decreased 0.69-fold (p = 0.41). Nondiabetic RYGB patients increased 2.21-fold (p = 0.07) versus a 0.81-fold (p = 0.37) decrease of nondiabetic band patients. CONCLUSIONS: This is one of the initial studies that show a significant increase in GIP gene expression following a RYGB. This increase correlates with the clinical resolution of T2D. The anatomical changes after RYGB may account for these changes. Based on this data, GIP may be a key peptide in the "foregut hypothesis" for resolution of T2D.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Derivação Gástrica , Polipeptídeo Inibidor Gástrico/genética , Gastroplastia , Diabetes Mellitus Tipo 2/cirurgia , Polipeptídeo Inibidor Gástrico/sangue , Expressão Gênica , Hemoglobinas Glicadas/análise , Humanos , Obesidade Mórbida/sangue , Obesidade Mórbida/cirurgia , Projetos Piloto , Período Pós-Operatório , Estudos Prospectivos , RNA/sangue , Reação em Cadeia da Polimerase em Tempo Real
5.
Surg Endosc ; 27(4): 1310-4, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23233000

RESUMO

BACKGROUND: Morbidly obese patients are at risk for nonalcoholic steatohepatitis (NASH) even in the absence of risk factors for liver disease. Unfortunately, NASH is usually not clinically evident, and a definitive, noninvasive test for NASH does not exist. Resistin, a cytokine originating from adipose tissue, is involved in insulin resistance and also initiates proinflammatory signaling from hepatic stellate cells. This study explores the relationship between resistin expression and liver pathology in bariatric surgery patients. METHODS: Blood samples from 30 patients undergoing bariatric surgery were collected. Total RNA was extracted and cDNA was synthesized. Quantitative RT-PCR was used to quantify relative gene expression using 18s rRNA gene as an internal control. Wedge liver biopsies from these patients were sectioned and stained. Based on a previously published scoring method, biopsies were assigned an overall NASH severity score and subscores for steatosis, inflammation, and fibrosis. Results were analyzed by using Student's t test. RESULTS: Resistin mRNA levels ranged from 0.5 to 9.7. A group of five patients with very high resistin expression (>4) was identified. These patients had a significantly higher average NASH score compared with the rest of the group (7.9 vs. 4.48, p = 0.019). Steatosis and inflammation scores were significantly higher in the high-resistin group (p < 0.05 for both comparisons). There also was a trend toward higher fibrosis score in this group, which approached statistical significance (p = 0.051). CONCLUSIONS: In morbidly obese patients, high resistin expression in serum is associated with hepatic steatosis, inflammation, and fibrosis. The development of elevated resistin expression may represent a link between obesity and the onset of steatohepatitis.


Assuntos
Fígado Gorduroso/etiologia , Obesidade Mórbida/complicações , Obesidade Mórbida/metabolismo , Resistina/biossíntese , Adulto , Cirurgia Bariátrica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/cirurgia
6.
J Cancer ; 14(4): 573-590, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37057291

RESUMO

Breast cancer development and progression are believed to be a sequential process, from normal to hyperplastic, to in situ, and to invasive and metastatic stages. Given that over 90% of cancer deaths are caused by invasive and metastatic lesions, countless factors and multiple theories have been proposed as the triggering factor for the cascade of actions of cancer invasion. However, those factors and theories are largely based on the studies of cell lines or animal models. In addition, corresponding interventions based on these factors and theories have failed to reduce the incidence rate of invasive and metastatic lesions, suggesting that previous efforts may have failed to arm at the right target. Considering these facts and observations, we are proposing "A focal aberrant degeneration in the myoepithelial cell layer (MECL) as the most likely triggering factor for breast cancer invasion". Our hypothesis is based on our recent studies of breast and multiple other cancers. Our commentary provides the rationale, morphologic, immunohistochemical, and molecular data to support our hypotheses. As all epithelium-derived cancers share a very similar architecture, our hypothesis is likely to be applicable to invasion of all cancer types. We believe that human tissue-derived data may provide a more realistic roadmap to guide the clinic practice.

7.
Am J Pathol ; 178(5): 2100-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21514425

RESUMO

Hepatic stellate cell transdifferentiation is a key event in the fibrogenic cascade. Therefore, attempts to prevent and/or revert the myofibroblastic phenotype could result in novel therapeutic approaches to treat liver cirrhosis. The expression of platelet-derived growth factor (PDGF)-ß receptor and the proliferative response to platelet-derived growth factor-ßß (PDGF-ßß) are hallmarks of the transdifferentiation of hepatic stellate cells (HSC). In this communication, we investigated whether thymosin-ß4 (Tß4), a chemokine expressed by HSC could prevent PDGF-BB-mediated proliferation and migration of cultured HSC. Using early passages of human HSC, we showed that Tß4 inhibited cell proliferation and migration and prevented the expression of PDGF-ß receptor (PDGF-ßr), α-smooth muscle actin and α1(I) collagen mRNAs. Tß4 also inhibited the reappearance of PDGF-ßr after its PDGF-BB-dependent degradation. These PDGF-dependent events were associated with the inhibition of AKT phosphorylation at both T308 and S473 amino acid residues. The lack of AKT phosphorylation was not due to the inhibition of PDGF-ßr phosphorylation, the activation of phosphoinositide 3-kinase (PI3K), pyruvate dehydrogenase kinase isozyme 1 (PDK1), and mammalian target of rapamycin (mTOR). We found that PDGF-BB induced AKT binding to actin, and that Tß4 prevented this effect. Tß4 also prevented the activation of freshly isolated HSC cultured in the presence of Dulbecco's modified Eagle's medium or Dulbecco's minimal essential medium containing 10% fetal bovine serum. In conclusion, overall, our findings suggest that Tß4 by sequestering actin prevents binding of AKT, thus inhibiting its phosphorylation. Therefore, Tß4 has the potential to be an antifibrogenic agent.


Assuntos
Actinas/metabolismo , Transdiferenciação Celular/fisiologia , Células Estreladas do Fígado/metabolismo , Fator de Crescimento Derivado de Plaquetas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Timosina/metabolismo , Becaplermina , Western Blotting , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Separação Celular , Transdiferenciação Celular/efeitos dos fármacos , Citometria de Fluxo , Imunofluorescência , Células Estreladas do Fígado/efeitos dos fármacos , Humanos , Imunoprecipitação , Cirrose Hepática/metabolismo , Fosforilação , Ligação Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-sis , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Timosina/farmacologia
8.
J Biol Chem ; 285(13): 10044-10052, 2010 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-20071335

RESUMO

Although metastasis-associated protein 1 (MTA1), a component of the nucleosome remodeling and deacetylase (NuRD) complex, is a DNA-damage response protein and regulates p53-dependent DNA repair, it remains unknown whether MTA1 also participates in p53-independent DNA damage response. Here, we provide evidence that MTA1 is a p53-independent transcriptional corepressor of p21(WAF1), and the underlying mechanism involves recruitment of MTA1-histone deacetylase 2 (HDAC2) complexes onto two selective regions of the p21(WAF1) promoter. Accordingly, MTA1 depletion, despite its effect on p53 down-regulation, superinduces p21(WAF1), increases p21(WAF1) binding to proliferating cell nuclear antigen (PCNA), and decreases the nuclear accumulation of PCNA in response to ionizing radiation. In support of a p53-independent role of MTA1 in DNA damage response, we further demonstrate that induced expression of MTA1 in p53-null cells inhibits p21(WAF1) promoter activity and p21(WAF1) binding to PCNA. Consequently, MTA1 expression in p53-null cells results in increased induction of gamma H2AX foci and DNA double strand break repair, and decreased DNA damage sensitivity following ionizing radiation treatment. These findings uncover a new target of MTA1 and the existence of an additional p53-independent role of MTA1 in DNA damage response, at least in part, by modulating the p21(WAF1)-PCNA pathway, and thus, linking two previously unconnected NuRD complex and DNA-damage response pathways.


Assuntos
Antígenos Nucleares/metabolismo , Núcleo Celular/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Histona Desacetilases/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Camundongos , Camundongos Knockout , Análise de Sequência com Séries de Oligonucleotídeos , Regiões Promotoras Genéticas , Transativadores
9.
Surg Endosc ; 25(6): 1962-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21181202

RESUMO

BACKGROUND: Type 2 diabetes (T2D) resolves rapidly after bariatric surgery, even before substantial weight is lost. However, the molecular pathways underlying this phenomenon remain unclear. Microarray data has shown that numerous genes are differentially expressed in blood after bariatric surgery, including resistin and leptin. Resistin and leptin are circulating hormones derived from adipose tissue, which are associated with obesity and insulin resistance. This study examined expression of these genes before and after bariatric surgery in diabetic and nondiabetic obese patients. METHODS: The study included 16 obese patients who underwent bariatric surgery, either Roux-en-Y gastric bypass (RYGB) or adjustable gastric banding. Eight patients had T2D. Preoperative blood samples were collected in PAXgene tubes to stabilize mRNA. Postoperative samples were collected 3 months after surgery. Total RNA was isolated and cDNA was synthesized. Real-time quantitative PCR was used to quantify mRNA. Results were analyzed using Student's t test with a P<0.05 considered significant. RESULTS: Postoperatively, five diabetic patients had discontinued hypoglycemic medications and one showed improved glycemic control. Both leptin and resistin mRNA levels were elevated in the diabetic group but decreased after surgery to levels near those of the nondiabetic group. Greater downregulation of resistin and leptin expression occurred in patients who lost more excess body weight (EBW), while patients who lost less than 10% EBW had a mean increase in expression of the two genes. Downregulation of both genes was more pronounced after RYGB compared to gastric banding. CONCLUSIONS: Downregulation of resistin and leptin gene expression after bariatric surgery may play a role in normalizing obesity-associated insulin resistance. Interestingly, downregulation is greater after RYGB and in patients who lose a greater proportion of EBW. Targeted therapies for obesity and diabetes may be developed by understanding the pathways by which these adipocytokines contribute to obesity and T2D.


Assuntos
Diabetes Mellitus Tipo 2/genética , Regulação da Expressão Gênica/fisiologia , Leptina/sangue , Resistina/sangue , Regulação para Baixo/fisiologia , Humanos , Resistência à Insulina/fisiologia , Leptina/genética , Análise em Microsséries , Obesidade Mórbida/genética , Obesidade Mórbida/cirurgia , Reação em Cadeia da Polimerase , Período Pós-Operatório , Resistina/genética , Redução de Peso/fisiologia
10.
J Cancer ; 12(23): 7138-7146, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34729115

RESUMO

Esophageal cancer (EC) is a lethal cancer with an extremely aggressive nature and poor survival rate. However, the molecular mechanisms driving the occurrence and progression of EC are not well understood. MicroRNAs (miRNAs) are small RNA molecules that regulate the expression of protein-coding genes. miRNA-mediated gene regulation plays an important role in EC. By cross-referencing studies from NCBI, we found that microRNA-375 (miR-375) is one of the most frequently downregulated miRNAs in EC. We assessed expression of miR-375 in EC cell lines and primary EC tissues and their matched normal tissues. We found significant downregulation of miR-375 in both cell lines and EC tissues. Forced expression of miR-375 attenuated EC cell proliferation and invasion. Human epidermal growth factor receptor 2 (HER2, ERBB2), a known proto-oncogene, was identified here as one of the potential target genes of miR-375. Ectopic expression of miR-375 significantly suppressed the expression of ERBB2 and subsequently downregulated one of its target genes, vascular endothelial growth factor A (VEGFA), which is related to cancer invasion and metastasis. These findings suggest that miR-375 acts as a tumor suppressor by blocking the ERBB2/VEGFA pathway with the potential to modulate the occurrence and/ or progression of EC.

11.
Cells ; 10(9)2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34571940

RESUMO

Lichen sclerosus (LS) is a chronic inflammatory skin disorder with unknown pathogenesis. The aberrant expression of microRNAs (miRNAs) is considered to exert a crucial role in LS. We used the next-generation sequencing technology (RNASeq) for miRNA profiling and Ingenuity Pathway Analysis (IPA) for molecular network analysis. We performed qRT-PCR, miRNA transfection and Matrigel assays for functional studies. We identified a total of 170 differentially expressed miRNAs between female LS and matched adjacent normal tissue using RNASeq, with 119 upregulated and 51 downregulated. Bioinformatics analysis revealed molecular networks that may shed light on the pathogenesis of LS. We verified the expression of a set of miRNAs that are related to autoimmunity, such as upregulated miR-326, miR-142-5p, miR-155 and downregulated miR-664a-3p and miR-181a-3p in LS tissue compared to the matched adjacent normal tissue. The differentially expressed miRNAs were also verified in blood samples from LS patients compared to healthy female volunteers. Functional studies demonstrated that a forced expression of miR-142-5p in human dermal fibroblast PCS-201-010 cells resulted in decreased cell proliferation and migration. These findings suggest that differentially expressed miRNAs may play an important role in LS pathogenesis; therefore, they could serve as biomarkers for LS management.


Assuntos
Biomarcadores/análise , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Líquen Escleroso e Atrófico/patologia , MicroRNAs/genética , Pele/metabolismo , Biologia Computacional , Feminino , Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Líquen Escleroso e Atrófico/genética
12.
Am J Cancer Res ; 11(7): 3594-3610, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34354862

RESUMO

Esophageal cancer (EC) is extremely aggressive and has a very poor survival rate. Esophageal squamous cell carcinoma (ESCC) accounts for 80% of all ECs worldwide, with the majority of the remaining 20% being esophageal adenocarcinoma (EAC). Due to its occult and insidious presentation, ESCC is typically diagnosed and treated in its advanced stages, thereby limiting the success of present therapeutic modalities. microRNAs (miRNAs) can function as tumor suppressors or oncogenes, playing critical roles in cancer initiation and progression by regulating target genes in oncogenic pathways. In the current study, we demonstrated that microRNA-196b (miR-196b) is one of the most upregulated miRNAs in both ESCC and EAC. miR-196b was overexpressed in ESCC and EAC cell lines, cellular exosomal RNAs, and ESCC tissue samples. Functional studies revealed that miR-196b acted as an oncomiR by directly targeting a tumor suppressor, ephrin type-A receptor 7 (EPHA7). EPHA7 abrogates the activity of ephrin type-A receptor 2 (EPHA2), a key molecule involved in the epithelial-to-mesenchymal transition (EMT) and MAPK/ERK pathways, mediating resistance to UV and chemoradiotherapy in both ESCC and EAC. Taken together, these findings suggest that miR-196b is a strong candidate molecular target for EC treatment.

13.
Surg Endosc ; 24(6): 1367-73, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20033714

RESUMO

BACKGROUND: Bariatric surgery can resolve type 2 diabetes in morbidly obese patients. However, the underlying mechanism is unknown. This study aimed to identify potential biomarkers or molecular pathways that are altered after bariatric surgery in diabetic and nondiabetic patients. METHODS: The study enrolled 17 morbidly obese patients undergoing bariatric surgery. Eight of the patients were diabetic, and nine were nondiabetic. In addition, a control group of four nonobese, nondiabetic volunteers was included. Patient blood samples were drawn before and after the operation. All blood samples were stabilized in Paxgene tubes (PreAnalytix). Total RNA was extracted and purified using the Paxgene Blood RNA Kit. For each sample, 100 ng of total RNA was amplified and labeled using the Ovation RNA Amplification System V2 with the Ovation Whole Blood reagent before hybridization to an Affymetrix Focus array containing more than 8,500 verified genes. Microarray results were analyzed with the GeneSpring GX 10.0 program, which uses an analysis of variance (ANOVA), and verified with real-time quantitative polymerase chain reaction (QPCR) using SYBR green (ABI). RESULTS: Microarray analysis showed that 167 genes were upregulated and 39 were downregulated in the obese diabetic patients. Preoperatively, adiponectin was downregulated 1.5-fold in diabetic versus nondiabetic patients. This was confirmed with quantitative PCR analysis. Preoperatively, morbidly obese patients showed a 3.12-fold downregulation of adiponectin expression versus the control group (p = 0.05). Interestingly, postoperative adiponectin levels were upregulated 2.79-fold (p = 0.02), which is close to the level of the normal control group. CONCLUSIONS: Adiponectin is dysregulated in obese patients and significantly dysregulated in obese diabetic patients. These findings correlate with the association between low levels of adiponectin and a predisposition to insulin resistance or diabetes. The data suggest that reactivation of adiponectin expression may play a part in the resolution of type 2 diabetes after bariatric surgery. Therefore, targeting adiponectin may help to develop alternative treatments for diabetes.


Assuntos
Adiponectina/genética , Cirurgia Bariátrica/métodos , Regulação da Expressão Gênica , Obesidade Mórbida/genética , RNA/genética , Adiponectina/biossíntese , Glicemia/metabolismo , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Feminino , Humanos , Masculino , Análise em Microsséries , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Reação em Cadeia da Polimerase , Resultado do Tratamento
14.
Surg Endosc ; 24(7): 1547-51, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20041267

RESUMO

BACKGROUND: Pathologic changes in the liver are common in morbidly obese patients, and insulin resistance may potentiate the progression of nonalcoholic steatohepatitis to fibrosis and cirrhosis. This study investigates the impact of leptin and adiponectin in morbidly obese diabetic and nondiabetic patients with regard to histopathologic changes in the liver. METHODS: Thirty-seven morbidly obese patients who underwent bariatric surgery with liver biopsies were enrolled in the study. Fourteen were diabetic and 23 were nondiabetic. Intraoperative liver tissue was sent for histopathologic analysis and extraneous intraoperative tissue was snap-frozen in liquid nitrogen. Total RNA was extracted and RNA was reverse transcribed to cDNA. Real-time quantitative PCR was performed to determine relative gene expression levels. The data were analyzed using a logarithmic transformation and normalized by 18S ribosome expression. Student's t test was used for statistical analysis with p < or = 0.05 as significant. RESULTS: Adiponectin expression was downregulated 4.4-fold (p < or = 0.05) in liver samples with evidence of inflammation on pathology. When hepatic inflammation was evaluated separately, there were no statistically significant differences in adiponectin levels between the diabetic and nondiabetic patients. However, overall adiponectin levels in hepatic samples of diabetic patients were 3.8-fold higher than those of nondiabetic patients (p < or = 0.05). There were no significant differences in leptin levels regardless of hepatic pathology or diabetic status. CONCLUSIONS: This study illustrates that there is a downregulation of adiponectin in morbidly obese patients with inflammatory infiltrates in the liver. Variations in adiponectin levels could be an indicator of disease progression since inflammatory infiltrates are commonly associated with nonalcoholic steatohepatitis (NASH) in morbidly obese patients. Currently, we are using human myofibroblasts derived from livers of morbidly obese people to further investigate the molecular mechanisms involved in the progression of fatty liver to fibrosis and cirrhosis.


Assuntos
Adiponectina/genética , Complicações do Diabetes , Fígado Gorduroso/patologia , Fígado/patologia , Obesidade Mórbida/cirurgia , Adiponectina/análise , Adulto , Biópsia , Complicações do Diabetes/genética , Progressão da Doença , Regulação para Baixo , Fígado Gorduroso/etiologia , Fígado Gorduroso/genética , Feminino , Expressão Gênica , Humanos , Resistência à Insulina , Leptina/análise , Leptina/genética , Cirrose Hepática/etiologia , Cirrose Hepática/genética , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/complicações
15.
J Cancer ; 11(7): 1693-1701, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32194781

RESUMO

Background: Endometrial cancer (EC) is a major gynecologic adenocarcinoma that arises from the endometrium. While the incidence of EC is on the rise worldwide, survivorship and clinical advancement have considerably lagged compared to other cancers. Given the sensitive nature of the endometrium and its high expression of hormone receptors, hormonal therapy has become a favorable alternative treatment compared to highly toxic chemotherapeutics and radiation therapy. Methods: Clinical samples from patients diagnosed with EC were obtained. ER and PR staining were performed according to the S-P kit, and HER2 staining was carried out according to the UltrasensitiveTM S-P immunohistochemistry kit protocol. Chi-square analysis was conducted using the SPSS. P-values of less than 0.05 were taken as an a priori value for statistical significance. Results: Immunohistochemical (IHC) analysis showed the overall positive expression rates of ER, PR, and HER2 to be 59.8%, 75.0%, and 71.1%, respectively. Significant co-expression was found among all three receptors, suggesting a cooperative, synergistic effect. More importantly, we found that ER expression was correlated with FIGO staging and cervical invasion, whereas PR expression was associated with histologic type. No clinicopathologic features were correlated with HER2 expression, but HER2 positivity was inversely associated with the degree of HER2 overexpression. Conclusions: These results suggest that EC is a heterogeneous disease that may not conform to traditional, prototypically defined subtypes. The status of ER, PR, and HER2 receptors may have the potential to serve as prognostic indicators for EC, but further analysis is needed to ascertain their prognostic significance.

16.
Retrovirology ; 6: 18, 2009 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-19220914

RESUMO

BACKGROUND: RNA interference is a gene regulatory mechanism that employs small RNA molecules such as microRNA. Previous work has shown that HIV-1 produces TAR viral microRNA. Here we describe the effects of the HIV-1 TAR derived microRNA on cellular gene expression. RESULTS: Using a variation of standard techniques we have cloned and sequenced both the 5' and 3' arms of the TAR miRNA. We show that expression of the TAR microRNA protects infected cells from apoptosis and acts by down-regulating cellular genes involved in apoptosis. Specifically, the microRNA down-regulates ERCC1 and IER3, protecting the cell from apoptosis. Comparison to our cloned sequence reveals possible target sites for the TAR miRNA as well. CONCLUSION: The TAR microRNA is expressed in all stages of the viral life cycle, can be detected in latently infected cells, and represents a mechanism wherein the virus extends the life of the infected cell for the purpose of increasing viral replication.


Assuntos
Apoptose/fisiologia , Regulação da Expressão Gênica , Repetição Terminal Longa de HIV/fisiologia , HIV-1/metabolismo , MicroRNAs/metabolismo , Sequência de Bases , Caspase 3/metabolismo , Linhagem Celular , Proteínas de Ligação a DNA/metabolismo , Endonucleases/metabolismo , Infecções por HIV/metabolismo , Infecções por HIV/virologia , Células HeLa , Interações Hospedeiro-Patógeno , Humanos , MicroRNAs/química , Ribonuclease III/metabolismo , Alinhamento de Sequência , Células U937
17.
Surg Endosc ; 23(6): 1292-7, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18855061

RESUMO

BACKGROUND: The causes of obesity are multifactorial but may include dysregulation of a family of related genes, such as the peroxisome proliferator activated receptor gamma (PPARgamma). When activated, the PPARgamma pathway promotes lipid metabolism. This study used microarray technology to evaluate differential gene expression profiles in obese patients undergoing bariatric surgery. METHODS: The study enrolled six morbidly obese patients with a body mass index (BMI) exceeding 35 and four nonobese individuals. Blood samples were stabilized in PaxGene tubes (PreAnalytiX), and total RNA was extracted. Next, 100 ng of total RNA was amplified and labeled using the Ovation RNA Amplification System V2 with the Ovation whole-blood reagent (NuGen) before it was hybridized to an Affymetrix (Santa Clara, CA) focus array containing more than 8,500 verified genes. The data were analyzed using an analysis of variance (ANOVA) (p < 0.05) in the GeneSpring program, and potential pathways were identified with the Ingenuity program. Real-time quantitative reverse transcriptase-polymerase chain reaction was used to validate the array data. RESULTS: A total of 97 upregulated genes and 125 downregulated genes were identified. More than a 1.5-fold change was identified between the morbidly obese patients and the control subjects for a cluster of dysregulated genes involving pathways regulating cell metabolism and lipid formation. Specifically, the PPARgamma pathway showed a plethora of dysregulated genes including tumor necrosis factor-alpha (TNFalpha). In morbidly obese patients, TNFalpha expression was increased (upregulated) 1.6-fold. These findings were confirmed using quantitative polymerase chain reaction with a 2.8-fold change. CONCLUSIONS: Microarrays are a powerful tool for identifying biomarkers indicating morbid obesity by analyzing differential gene expression profiles. This study confirms the association of PPARgamma with morbid obesity. Also, these findings in blood support previous work documented in tissue (omentum, liver, and stomach). Based on these findings in blood, the authors plan to explore postoperative changes in gene expression by analyzing blood samples after bariatric surgery. Ultimately, these findings may promote the development of therapeutic agents targeted to specific dysfunctional genes.


Assuntos
Regulação da Expressão Gênica , Predisposição Genética para Doença , Obesidade Mórbida/genética , PPAR gama/genética , RNA/genética , Transdução de Sinais/genética , Adulto , Idoso , Índice de Massa Corporal , Humanos , Pessoa de Meia-Idade , Obesidade Mórbida/sangue , Análise de Sequência com Séries de Oligonucleotídeos , PPAR gama/sangue , Reação em Cadeia da Polimerase , Prognóstico , Adulto Jovem
18.
Surg Endosc ; 23(4): 700-4, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18806947

RESUMO

INTRODUCTION: The cause of diabetes in morbidly obese patients is multifactorial, including genetic, social, and dietary components. Transcription factor 7-like 2 (TCF7L2) is a gene that is related to the development of diabetes. This pilot study examines TCF7L2 expression in liver samples obtained from morbidly obese patients undergoing bariatric surgery. TCF7L2 expression is compared between diabetic and nondiabetic patients. METHODS: Liver samples were obtained from 20 morbidly obese patients undergoing bariatric surgery. Samples were flash frozen in liquid nitrogen. Total RNA was extracted from tissue samples using the TRIzol reagent (Invitrogen Inc, Carlsbad, CA). Using the iScript cDNA synthesis kit (Bio-Rad Laboratories, Hercules,CA), cDNA was synthesized. Quantitative polymerase chain reaction (qPCR) was done using SYBR Green qPCR Reagents (Stratagene, Cedar Creek TX) and the 7300 Real-Time PCR system (Applied Biosystems, Foster City CA). Preoperative demographic and gene expression data were correlated using univariate analysis and logistic regression models. Only associations with a p-value less than 0.05 were considered significant. RESULTS: For the entire group, there was no correlation between body mass index (BMI) and TCF7L2 expression. In morbidly obese nondiabetic patients, there was a positive correlation between TCF7L2 expression and BMI (R(2)=0.21). In morbidly obese diabetic patients, there was an inverse correlation between TCF7L2 expression and BMI (R(2)=0.58). There was no significant relationship between TCF7L2 expression and age or glycosylated hemoglobin (HbA1c). CONCLUSIONS: The cause of diabetes is multifactorial but the data from our pilot study documents the relationship of TCF7L2 with type 2 diabetes in morbidly obese patients.


Assuntos
Cirurgia Bariátrica , Diabetes Mellitus Tipo 2/genética , Expressão Gênica , Obesidade Mórbida/cirurgia , RNA/genética , Fatores de Transcrição TCF/genética , Adulto , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/etiologia , Hemoglobinas Glicadas/metabolismo , Sequências Hélice-Alça-Hélice , Humanos , Pessoa de Meia-Idade , Obesidade Mórbida/sangue , Obesidade Mórbida/complicações , Reação em Cadeia da Polimerase , Fatores de Transcrição TCF/biossíntese , Proteína 2 Semelhante ao Fator 7 de Transcrição , Adulto Jovem
19.
Int J Biol Sci ; 15(7): 1429-1439, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31337973

RESUMO

Lichen sclerosus (LS) is an inflammatory dermatosis with a predilection for anogenital skin. Developing lesions lead to vulvar pain and sexual dysfunction, with a significant loss of structural anatomical architecture, sclerosis, and increased risk of malignancy. Onset may occur at any age in both sexes, but typically affects more females than males, presenting in a bimodal fashion among pre-pubertal children and middle-aged adults. A definitive cure remains elusive as the exact pathogenesis of LS remains unknown. A general review of LS, histologic challenges, along with amounting support for LS as an autoimmune disease with preference for a Th1 immune response against a genetic background is summarized. In addition to the classically referenced ECM1 (extracellular matrix protein 1), a following discussion of other immune and genetic targets more recently implicated as causative or accelerant agents of disease, particularly miR-155, downstream targets of ECM1, galectin-7, p53, and epigenetic modifications to CDKN2A, are addressed from the viewpoint of their involvement in three different, but interconnected aspects of LS pathology. Collectively, these emerging targets serve not only as inherently potential therapeutic targets for treatment, but may also provide further insight into this debilitating and cryptic disease.


Assuntos
Líquen Escleroso e Atrófico/genética , Líquen Escleroso e Atrófico/imunologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/imunologia , Colágeno Tipo V/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Progressão da Doença , Epigênese Genética , Proteínas da Matriz Extracelular/metabolismo , Galectinas/metabolismo , Humanos , Sistema Imunitário , Incidência , Líquen Escleroso e Atrófico/patologia , MicroRNAs/metabolismo , Estresse Oxidativo , Proteína Supressora de Tumor p53/metabolismo
20.
Thromb Haemost ; 119(9): 1451-1460, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31266078

RESUMO

Aspirin has been widely used for the prevention of cardiovascular diseases, but its antiplatelet efficiency varies between individuals. The present study aimed to evaluate response to aspirin based on gene profiles as well as potential regulating pathways using human blood samples and cell lines. Platelet function in patients 50 years or older with coronary artery disease on 100 mg/day aspirin was measured by light transmission aggregometry (LTA) of arachidonic acid (AA)-induced platelet aggregation. The expression of eight candidate genes-PTGS1/COX1, PLA2G4A, PLA2G6, PLA2G7, TBXAS1, TBXA2R, PTGIR, and ITGA2B-and the ingredients involved in AA metabolism were analyzed. Our data showed that the expressions of thromboxane A synthase 1 (TBXAS1), thromboxane synthase (TXS), and thromboxane B2 (TXB2) were increased in the upper quartile of platelet aggregation (LTA-AA_Q4) group compared with the lower quartile of platelet aggregation (LTA-AA_Q1) group. Our bioinformatics analysis suggested that TBXAS1 was targeted by miR-34b-3p via binding to its 3'-UTR, which was subsequently verified experimentally. Although overexpression of miR-34b-3p exhibited no apparent effect on cell proliferation, inhibition of miR-34b-3p promoted megakaryocyte viability. Our data demonstrated that the expression of TBXAS1 was higher in the aspirin hyporesponsiveness group than that in the hyperresponsiveness group, suggesting that high expression of TBXAS1 may be associated with aspirin hyporesponsiveness. miR-34b-3p may regulate the platelet and aspirin response by suppressing TBXAS1 expression and megakaryocyte proliferation.


Assuntos
Aspirina/uso terapêutico , Plaquetas/fisiologia , Doenças Cardiovasculares/genética , Megacariócitos/fisiologia , MicroRNAs/genética , Inibidores da Agregação Plaquetária/uso terapêutico , Tromboxano-A Sintase/genética , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Farmacológicos , Doenças Cardiovasculares/tratamento farmacológico , Linhagem Celular , Proliferação de Células , Resistência a Medicamentos , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Agregação Plaquetária/genética , Tromboxano B2/genética
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