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1.
Diagn Cytopathol ; 51(8): E239-E241, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37218746

RESUMO

Trichophyton is a dermatophytic fungi causing superficial skin infections which affects outermost layer of the epidermis, stratum corneum, and mainly involves feet, groin, scalp, and nails. Invasion into the dermis occurs mainly in immunocompromised patients. A 75-year-old hypertensive female presented with a nodular swelling on the dorsum of right foot for 1 month. The swelling was 1.0 × 1.0 cm and gradually progressive in nature. FNAC revealed many thin filamentous branching and fungal hyphae along with foreign body granulomas and suppurative acute inflammation. The swelling was excised and sent for histopathological examination which confirmed the above findings. Periodic Acid Schiff stain showed fungal hyphae in both cytology smear as well as histopathology section. On fungal culture, microconidia with septate hyphae suggestive of Trichophyton rubrum was seen. Trichophytons mainly affect immunocompromised and diabetic patients, however, may present as nodular lesions without any history of superficial dermatophytosis as seen in the present case. The characteristic cytological picture helped to clinch the diagnosis in this case and facilitated further management.


Assuntos
Tinha , Humanos , Feminino , Idoso , Tinha/microbiologia , Trichophyton , Couro Cabeludo
2.
Antioxidants (Basel) ; 12(2)2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36829837

RESUMO

Cyclobutane pyrimidine dimers (CPDs) are ultraviolet radiation (UV)-induced carcinogenic DNA photoproducts that lead to UV signature mutations in melanoma. Previously, we discovered that, in addition to their incident formation (iCPDs), UV exposure induces melanin chemiexcitation (MeCh), where UV generates peroxynitrite (ONOO-), which oxidizes melanin into melanin-carbonyls (MCs) in their excited triplet state. Chronic MeCh and energy transfer by MCs to DNA generates CPDs for several hours after UV exposure ends (dark CPD, dCPDs). We hypothesized that MeCh and the resulting dCPDs can be inhibited using MeCh inhibitors, and MC and ONOO- scavengers. Here, we investigated the efficacy of Acetyl Zingerone (AZ), a plant-based phenolic alkanone, and its chemical analogs in inhibiting iCPDs and dCPDs in skin fibroblasts, keratinocytes, and isogenic pigmented and albino melanocytes. While AZ and its methoxy analog, 3-(4-Methoxy-benzyl)-Pentane-2,4-dione (MBPD) completely inhibited the dCPDs, MBPD also inhibited ~50% of iCPDs. This suggests the inhibition of ~80% of total CPDs at any time point post UV exposure by MBPD, which is markedly significant. MBPD downregulated melanin synthesis, which is indispensable for dCPD generation, but this did not occur with AZ. Meanwhile, AZ and MBPD both upregulated the expression of nucleotide excision repair (NER) pathways genes including Xpa, Xpc, and Mitf. AZ and its analogs were non-toxic to the skin cells and did not act as photosensitizers. We propose that AZ and MBPD represent "next-generation skin care additives" that are safe and effective for use not only in sunscreens but also in other specialized clinical applications owing to their extremely high efficacy in blocking both iCPDs and dCPDs.

4.
Indian J Palliat Care ; 27(1): 76-82, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34035621

RESUMO

AIM: The role of social support network in managing psychological symptoms in cancer patients is widely acknowledged. The purpose of this study was to investigate the potential mediating role of Affective experiences in the relationship between perceived social support (PSS) and life satisfaction (LS) among breast cancer patients in India. METHODS: A total of 100 breast cancer patients from S. S. Hospital, Banaras Hindu University participated in the study. They were tested using the PGI Social Support questionnaire, Satisfaction with Life Scale and Scale of Positive and Negative Experiences. RESULTS: Co-relational results indicated that PSS was positively associated with positive affect and LS, while inversely related to negative affect. Affect was also associated with LS. Results showed that the mediation of affective experiences in the relationship between PSS and LS was significant (P <.01 level). CONCLUSION: Both PSS played a big role in LS among breast cancer patients. Besides focusing on improvement of the social support network, the psychologists and counsellors should adopt an integrated approach for evidence-based intervention strategies to enhance their ability to effectively balance their positive and negative emotions to promote LS among cancer patients.

5.
Prep Biochem Biotechnol ; 49(6): 567-577, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30929621

RESUMO

Polyhydroxyalkanoates (PHAs) are intracellular carbon and energy storage reserve material stored by gram-negative bacteria under nutrient limitation. PHAs are best alternative biodegradable plastics (bio-plastics) due to their resemblance to conventional synthetic plastic. The present study investigated the synergistic effect of nutritional supplements (amino acid and vitamin) on the PHA production by Alcaligenes sp. NCIM 5085 utilizing a sugar refinery waste (cane molasses) under submerged fermentation process. Initially, the effect of individual factor on PHA yield was studied by supplementing amino acids (cysteine, isoleucine, and methionine), vitamin (thiamin), and cane molasses at varying concentration in the production medium. Further, the cultivation medium was optimized by varying the levels of cane molasses, methionine and thiamin using response surface methodology to enhance the PHA yield. The maximum PHA yield of 70.89% was obtained under the optimized condition, which was then scaled up on 7.5 L-bioreactor. Batch cultivation in 7.5 L-bioreactor under the optimized condition gave a maximum PHA yield and productivity of 79.26% and 0.312 gL-1 h-1, respectively. The PHA produced was subsequently characterized as PHB by FTIR. PHB extracted was of relatively high molecular weight and crystallinity index. DSC analysis gave Tg, Tm, and Xc of 4.2, 179 °C and 66%, respectively. TGA analysis showed thermal stability with maximized degradation occurring at 302 °C, which is above the melting temperature (179 °C) of the purified polymer. The extracted polymer, therefore, possessed desirable material properties to be used in food packaging.


Assuntos
Aminoácidos/metabolismo , Poli-Hidroxialcanoatos/biossíntese , Tiamina/metabolismo , Alcaligenes/metabolismo , Reatores Biológicos , Cisteína/metabolismo , Fermentação , Embalagem de Alimentos , Resíduos Industriais/prevenção & controle , Isoleucina/metabolismo , Metionina/metabolismo , Melaço , Peso Molecular , Poli-Hidroxialcanoatos/química , Temperatura de Transição , Gerenciamento de Resíduos/métodos
6.
Hepatology ; 66(2): 466-480, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28437865

RESUMO

Nonalcoholic steatohepatitis (NASH) is the most prevalent cause of chronic liver disease in the Western world. However, an optimum therapy for NASH is yet to be established, mandating more in-depth investigation into the molecular pathogenesis of NASH to identify novel regulatory molecules and develop targeted therapies. Here, we unravel a unique function of astrocyte elevated gene-1(AEG-1)/metadherin in NASH using a transgenic mouse with hepatocyte-specific overexpression of AEG-1 (Alb/AEG-1) and a conditional hepatocyte-specific AEG-1 knockout mouse (AEG-1ΔHEP ). Alb/AEG-1 mice developed spontaneous NASH whereas AEG-1ΔHEP mice were protected from high-fat diet (HFD)-induced NASH. Intriguingly, AEG-1 overexpression was observed in livers of NASH patients and wild-type (WT) mice that developed steatosis upon feeding HFD. In-depth molecular analysis unraveled that inhibition of peroxisome proliferator-activated receptor alpha activity resulting in decreased fatty acid ß-oxidation, augmentation of translation of fatty acid synthase resulting in de novo lipogenesis, and increased nuclear factor kappa B-mediated inflammation act in concert to mediate AEG-1-induced NASH. Therapeutically, hepatocyte-specific nanoparticle-delivered AEG-1 small interfering RNA provided marked protection from HFD-induced NASH in WT mice. CONCLUSION: AEG-1 might be a key molecule regulating initiation and progression of NASH. AEG-1 inhibitory strategies might be developed as a potential therapeutic intervention in NASH patients. (Hepatology 2017;66:466-480).


Assuntos
Regulação da Expressão Gênica , Glicoproteínas de Membrana/genética , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , PPAR alfa/metabolismo , Análise de Variância , Animais , Biópsia por Agulha , Células Cultivadas , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos CBA , Camundongos Transgênicos , Distribuição Aleatória , Papel (figurativo)
7.
Bioconjug Chem ; 26(8): 1651-61, 2015 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-26079152

RESUMO

Hepatocellular carcinoma (HCC) is a fatal cancer with no effective therapy. Astrocyte elevated gene-1 (AEG-1) plays a pivotal role in hepatocarcinogenesis and inhibits retinoic acid-induced gene expression and cell death. The combination of a lentivirus expressing AEG-1 shRNA and all-trans retinoic acid (ATRA) profoundly and synergistically inhibited subcutaneous human HCC xenografts in nude mice. We have now developed liver-targeted nanoplexes by conjugating poly(amidoamine) (PAMAM) dendrimers with polyethylene glycol (PEG) and lactobionic acid (Gal) (PAMAM-PEG-Gal) which were complexed with AEG-1 siRNA (PAMAM-AEG-1si). The polymer conjugate was characterized by (1)H-NMR, MALDI, and mass spectrometry; and optimal nanoplex formulations were characterized for surface charge, size, and morphology. Orthotopic xenografts of human HCC cell QGY-7703 expressing luciferase (QGY-luc) were established in the livers of athymic nude mice and tumor development was monitored by bioluminescence imaging (BLI). Tumor-bearing mice were treated with PAMAM-siCon, PAMAM-siCon+ATRA, PAMAM-AEG-1si, and PAMAM-AEG-1si+ATRA. In the control group the tumor developed aggressively. ATRA showed little effect due to high AEG-1 levels in QGY-luc cells. PAMAM-AEG-1si showed significant reduction in tumor growth, and the combination of PAMAM-AEG-1si+ATRA showed profound and synergistic inhibition so that the tumors were almost undetectable by BLI. A marked decrease in AEG-1 level was observed in tumor samples treated with PAMAM-AEG-1si. The group treated with PAMAM-AEG-1si+ATRA nanoplexes showed increased necrosis, inhibition of proliferation, and increased apoptosis when compared to other groups. Liver is an ideal organ for RNAi therapy and ATRA is an approved anticancer agent. Our exciting observations suggest that the combinatorial approach might be an effective way to combat HCC.


Assuntos
Carcinoma Hepatocelular/terapia , Moléculas de Adesão Celular/antagonistas & inibidores , Neoplasias Hepáticas/terapia , Nanopartículas/administração & dosagem , RNA Interferente Pequeno/genética , Tretinoína/farmacologia , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Moléculas de Adesão Celular/genética , Proliferação de Células/efeitos dos fármacos , Terapia Combinada , Terapia Genética , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Nanopartículas/química , Proteínas de Ligação a RNA , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
8.
J Biol Chem ; 290(29): 18227-18236, 2015 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-26070567

RESUMO

Astrocyte elevated gene-1 (AEG-1), also known as MTDH (metadherin) or LYRIC, is an established oncogene. However, the physiological function of AEG-1 is not known. To address this question, we generated an AEG-1 knock-out mouse (AEG-1KO) and characterized it. Although AEG-1KO mice were viable and fertile, they were significantly leaner with prominently less body fat and lived significantly longer compared with wild type (WT). When fed a high fat and cholesterol diet (HFD), WT mice rapidly gained weight, whereas AEG-1KO mice did not gain weight at all. This phenotype of AEG-1KO mice is due to decreased fat absorption from the intestines, not because of decreased fat synthesis or increased fat consumption. AEG-1 interacts with retinoid X receptor (RXR) and inhibits RXR function. In enterocytes of AEG-1KO mice, we observed increased activity of RXR heterodimer partners, liver X receptor and peroxisome proliferator-activated receptor-α, key inhibitors of intestinal fat absorption. Inhibition of fat absorption in AEG-1KO mice was further augmented when fed an HFD providing ligands to liver X receptor and peroxisome proliferator-activated receptor-α. Our studies reveal a novel role of AEG-1 in regulating nuclear receptors controlling lipid metabolism. AEG-1 may significantly modulate the effects of HFD and thereby function as a unique determinant of obesity.


Assuntos
Mucosa Intestinal/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Proteínas de Membrana/metabolismo , Aumento de Peso , Tecido Adiposo/metabolismo , Animais , Homeostase , Receptores X do Fígado , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/genética , Obesidade/metabolismo , Receptores Nucleares Órfãos/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Proteínas de Ligação a RNA , Receptores X de Retinoides/metabolismo
9.
J Biol Chem ; 290(25): 15549-15558, 2015 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-25944909

RESUMO

Non-thyroidal illness syndrome (NTIS), characterized by low serum 3,5,3'-triiodothyronine (T3) with normal l-thyroxine (T4) levels, is associated with malignancy. Decreased activity of type I 5'-deiodinase (DIO1), which converts T4 to T3, contributes to NTIS. T3 binds to thyroid hormone receptor, which heterodimerizes with retinoid X receptor (RXR) and regulates transcription of target genes, such as DIO1. NF-κB activation by inflammatory cytokines inhibits DIO1 expression. The oncogene astrocyte elevated gene-1 (AEG-1) inhibits RXR-dependent transcription and activates NF-κB. Here, we interrogated the role of AEG-1 in NTIS in the context of hepatocellular carcinoma (HCC). T3-mediated gene regulation was analyzed in human HCC cells, with overexpression or knockdown of AEG-1, and primary hepatocytes from AEG-1 transgenic (Alb/AEG-1) and AEG-1 knock-out (AEG-1KO) mice. Serum T3 and T4 levels were checked in Alb/AEG-1 mice and human HCC patients. AEG-1 and DIO1 levels in human HCC samples were analyzed by immunohistochemistry. AEG-1 inhibited T3-mediated gene regulation in human HCC cells and mouse hepatocytes. AEG-1 overexpression repressed and AEG-1 knockdown induced DIO1 expression. An inverse correlation was observed between AEG-1 and DIO1 levels in human HCC patients. Low T3 with normal T4 was observed in the sera of HCC patients and Alb/AEG-1 mice. Inhibition of co-activator recruitment to RXR and activation of NF-κB were identified to play a role in AEG-1-mediated down-regulation of DIO1. AEG-1 thus might play a role in NTIS associated with HCC and other cancers.


Assuntos
Carcinoma Hepatocelular/metabolismo , Moléculas de Adesão Celular/metabolismo , Síndromes do Eutireóideo Doente/metabolismo , Neoplasias Hepáticas/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Moléculas de Adesão Celular/genética , Linhagem Celular Tumoral , Regulação para Baixo/genética , Síndromes do Eutireóideo Doente/etiologia , Síndromes do Eutireóideo Doente/genética , Regulação Enzimológica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/genética , Células HEK293 , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Iodeto Peroxidase/biossíntese , Iodeto Peroxidase/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Glicoproteínas de Membrana/genética , Proteínas de Membrana , Camundongos , Camundongos Knockout , NF-kappa B/genética , NF-kappa B/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Ligação a RNA , Receptores X de Retinoides/genética , Receptores X de Retinoides/metabolismo , Tri-Iodotironina/genética , Tri-Iodotironina/metabolismo
10.
J Cell Sci ; 128(6): 1083-9, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25616899

RESUMO

Increased production and assembly of extracellular matrix proteins during transdifferentiation of epithelial cells to a mesenchymal phenotype contributes to diseases such as renal and pulmonary fibrosis. TGF-ß and hypoxia, two cues that initiate injury-induced fibrosis, caused human kidney cells to develop a mesenchymal phenotype, including increased fibronectin expression and secretion. However, upon hypoxia, assembled extracellular fibronectin fibrils were mostly absent, whereas treatment with TGF-ß led to abundant fibrils. Fibrillogenesis required cell-generated force and tension. TGF-ß, but not hypoxia, increased cell contractility, as determined by phosphorylation of myosin light chain and quantifying force and tension generated by cells plated on engineered elastomeric microposts. Additionally, TGF-ß, but not hypoxia, increased the activation of integrins. However, experimentally activating integrins markedly increased the levels of phosphorylated myosin light chain and fibronectin fibril assembly upon hypoxia. Our findings show that deficient integrin activation and subsequent lack of cell contractility are mechanisms that mediate a lack of fibrillogenesis upon hypoxia and they challenge current views on oxygen deprivation being sufficient for fibrosis.


Assuntos
Transdiferenciação Celular , Células Epiteliais/citologia , Matriz Extracelular/metabolismo , Fibronectinas/metabolismo , Fibrose/patologia , Hipóxia/fisiopatologia , Túbulos Renais Proximais/citologia , Western Blotting , Células Cultivadas , Células Epiteliais/metabolismo , Fibrose/metabolismo , Humanos , Integrinas/metabolismo , Túbulos Renais Proximais/metabolismo , Fator de Crescimento Transformador beta/metabolismo
11.
Hepat Oncol ; 2(3): 303-312, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26798451

RESUMO

AEG-1 is an oncogene that is overexpressed in all cancers, including hepatocellular carcinoma. AEG-1 plays a seminal role in promoting cancer development and progression by augmenting proliferation, invasion, metastasis, angiogenesis and chemoresistance, all hallmarks of aggressive cancer. AEG-1 mediates its oncogenic function predominantly by interacting with various protein complexes. AEG-1 acts as a scaffold protein, activating multiple protumorigenic signal transduction pathways, such as MEK/ERK, PI3K/Akt, NF-κB and Wnt/ß-catenin while regulating gene expression at transcriptional, post-transcriptional and translational levels. Our recent studies document that AEG-1 is fundamentally required for activation of inflammation. A comprehensive and convincing body of data currently points to AEG-1 as an essential component critical to the onset and progression of cancer. The present review describes the current knowledge gleaned from patient and experimental studies as well as transgenic and knockout mouse models, on the impact of AEG-1 on hepatocarcinogenesis.

12.
Hepatology ; 61(3): 915-29, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25065684

RESUMO

UNLABELLED: Astrocyte elevated gene-1 (AEG-1) and c-Myc are overexpressed in human hepatocellular carcinoma (HCC) functioning as oncogenes. AEG-1 is transcriptionally regulated by c-Myc, and AEG-1 itself induces c-Myc by activating the Wnt/ß-catenin-signaling pathway. We now document the cooperation of AEG-1 and c-Myc in promoting hepatocarcinogenesis by analyzing hepatocyte-specific transgenic mice expressing either AEG-1 (albumin [Alb]/AEG-1), c-Myc (Alb/c-Myc), or both (Alb/AEG-1/c-Myc). Wild-type and Alb/AEG-1 mice did not develop spontaneous HCC. Alb/c-Myc mice developed spontaneous HCC without distant metastasis, whereas Alb/AEG-1/c-Myc mice developed highly aggressive HCC with frank metastasis to the lungs. Induction of carcinogenesis by N-nitrosodiethylamine significantly accelerated the kinetics of tumor formation in all groups. However, in Alb/AEG-1/c-Myc, the effect was markedly pronounced with lung metastasis. In vitro analysis showed that Alb/AEG-1/c-Myc hepatocytes acquired increased proliferation and transformative potential with sustained activation of prosurvival and epithelial-mesenchymal transition-signaling pathways. RNA-sequencing analysis identified a unique gene signature in livers of Alb/AEG-1/c-Myc mice that was not observed when either AEG-1 or c-Myc was overexpressed. Specifically, Alb/AEG-1/c-Myc mice overexpressed maternally imprinted noncoding RNAs (ncRNAs), such as Rian, Meg-3, and Mirg, which are implicated in hepatocarcinogenesis. Knocking down these ncRNAs significantly inhibited proliferation and invasion by Alb/AEG-1/c-Myc hepatocytes. CONCLUSION: Our studies reveal a novel cooperative oncogenic effect of AEG-1 and c-Myc that might explain the mechanism of aggressive HCC. Alb/AEG-1/c-Myc mice provide a useful model to understand the molecular mechanism of cooperation between these two oncogenes and other molecules involved in hepatocarcinogenesis. This model might also be of use for evaluating novel therapeutic strategies targeting HCC.


Assuntos
Neoplasias Hepáticas Experimentais/etiologia , Proteínas de Membrana/fisiologia , Proteínas Proto-Oncogênicas c-myc/fisiologia , Albuminas/análise , Animais , Carcinogênese , Células Cultivadas , Transição Epitelial-Mesenquimal , Neoplasias Hepáticas Experimentais/patologia , Neoplasias Pulmonares/secundário , Proteínas de Membrana/análise , Camundongos , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-myc/análise , Proteínas de Ligação a RNA
13.
Int J Oncol ; 46(2): 465-73, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25405367

RESUMO

The staphylococcal nuclease and tudor domain containing 1 (SND1) is a multifunctional protein overexpressed in breast, prostate, colorectal and hepatocellular carcinomas and malignant glioma. Molecular studies have revealed the multifaceted activities of SND1 involved in regulating gene expression at transcriptional as well as post-transcriptional levels. Early studies identified SND1 as a transcriptional co-activator. SND1 is also a component of RNA-induced silencing complex (RISC) thus mediating RNAi function, a regulator of mRNA splicing, editing and stability, and plays a role in maintenance of cell viability. Such diverse actions allow the SND1 to modulate a complex array of molecular networks, thereby promoting carcinogenesis. Here, we describe the crucial role of SND1 in cancer development and progression, and highlight SND1 as a potential target for therapeutic intervention.


Assuntos
Transformação Celular Neoplásica/genética , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias/genética , Proteínas Nucleares/genética , Carboxipeptidases/genética , Endonucleases , Humanos , Terapia de Alvo Molecular , Neoplasias/patologia , Proteínas Nucleares/biossíntese , Interferência de RNA , Splicing de RNA/genética
14.
Cancer Res ; 74(21): 6184-93, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25193383

RESUMO

Activation of the oncogene AEG-1 (MTDH, LYRIC) has been implicated recently in the development of hepatocellular carcinoma (HCC). In mice, HCC can be initiated by exposure to the carcinogen DEN, which has been shown to rely upon activation of NF-κB in liver macrophages. Because AEG-1 is an essential component of NF-κB activation, we interrogated the susceptibility of mice lacking the AEG-1 gene to DEN-induced hepatocarcinogenesis. AEG-1-deficient mice displayed resistance to DEN-induced HCC and lung metastasis. No difference was observed in the response to growth factor signaling or activation of AKT, ERK, and ß-catenin, compared with wild-type control animals. However, AEG-1-deficient hepatocytes and macrophages exhibited a relative defect in NF-κB activation. Mechanistic investigations showed that IL6 production and STAT3 activation, two key mediators of HCC development, were also deficient along with other biologic and epigenetics findings in the tumor microenvironment, confirming that AEG-1 supports an NF-κB-mediated inflammatory state that drives HCC development. Overall, our findings offer in vivo proofs that AEG-1 is essential for NF-κB activation and hepatocarcinogenesis, and they reveal new roles for AEG-1 in shaping the tumor microenvironment for HCC development.


Assuntos
Carcinoma Hepatocelular/genética , Moléculas de Adesão Celular/genética , Neoplasias Hepáticas/genética , Neoplasias Experimentais/genética , Animais , Carcinogênese/genética , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/secundário , Proteínas de Membrana , Camundongos , NF-kappa B , Neoplasias Experimentais/induzido quimicamente , Proteínas de Ligação a RNA , Transdução de Sinais/genética
15.
Cancer Res ; 74(16): 4364-77, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25125681

RESUMO

Retinoid X receptor (RXR) regulates key cellular responses such as cell growth and development, and this regulation is frequently perturbed in various malignancies, including hepatocellular carcinoma (HCC). However, the molecule(s) that physically govern this deregulation are mostly unknown. Here, we identified RXR as an interacting partner of astrocyte-elevated gene-1 (AEG-1)/metadherin (MTDH), an oncogene upregulated in all cancers. Upon interaction, AEG-1 profoundly inhibited RXR/retinoic acid receptor (RAR)-mediated transcriptional activation. Consequently, AEG-1 markedly protected HCC and acute myelogenous leukemia (AML) cells from retinoid- and rexinoid-induced cell death. In nontumorigenic cells and primary hepatocytes, AEG-1/RXR colocalizes in the nucleus in which AEG-1 interferes with recruitment of transcriptional coactivators to RXR, preventing transcription of target genes. In tumor cells and AEG-1 transgenic hepatocytes, overexpressed AEG-1 entraps RXR in cytoplasm, precluding its nuclear translocation. In addition, ERK, activated by AEG-1, phosphorylates RXR that leads to its functional inactivation and attenuation of ligand-dependent transactivation. In nude mice models, combination of all-trans retinoic acid (ATRA) and AEG-1 knockdown synergistically inhibited growth of human HCC xenografts. The present study establishes AEG-1 as a novel homeostatic regulator of RXR and RXR/RAR that might contribute to hepatocarcinogenesis. Targeting AEG-1 could sensitize patients with HCC and AML to retinoid- and rexinoid-based therapeutics.


Assuntos
Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Receptores X de Retinoides/metabolismo , Retinoides/antagonistas & inibidores , Animais , Moléculas de Adesão Celular/antagonistas & inibidores , Diferenciação Celular/fisiologia , Técnicas de Silenciamento de Genes , Células HEK293 , Xenoenxertos , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Nus , Camundongos Transgênicos , Fosforilação , Regiões Promotoras Genéticas , Proteínas de Ligação a RNA , Receptores X de Retinoides/antagonistas & inibidores , Receptores X de Retinoides/genética , Retinoides/metabolismo , Transdução de Sinais , Transfecção , Tretinoína/farmacologia , Regulação para Cima
16.
FEBS Open Bio ; 4: 353-61, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24918049

RESUMO

Staphylococcal nuclease domain containing-1 (SND1) is overexpressed in human hepatocellular carcinoma (HCC) patients and promotes tumorigenesis by human HCC cells. We now document that SND1 increases angiotensin II type 1 receptor (AT1R) levels by increasing AT1R mRNA stability. This results in activation of ERK, Smad2 and subsequently the TGFß signaling pathway, promoting epithelial-mesenchymal transition (EMT) and migration and invasion by human HCC cells. A positive correlation was observed between SND1 and AT1R expression levels in human HCC patients. Small molecule inhibitors of SND1, alone or in combination with AT1R blockers, might be an effective therapeutic strategy for late-stage aggressive HCC.

17.
J Hepatocell Carcinoma ; 1: 9-19, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-27508172

RESUMO

Hepatocellular carcinoma (HCC) is a vicious and highly vascular cancer with a dismal prognosis. It is a life-threatening illness worldwide that ranks fifth in terms of cancer prevalence and third in cancer deaths. Most patients are diagnosed at an advanced stage by which time conventional therapies are no longer effective. Targeted molecular therapies, such as the multikinase inhibitor sorafenib, provide a modest increase in survival for advanced HCC patients and display significant toxicity. Thus, there is an immense need to identify novel regulators of HCC that might be targeted effectively. The insulin-like growth factor (IGF) axis is commonly abnormal in HCC. Upon activation, the IGF axis controls metabolism, tissue homeostasis, and survival. Insulin-like growth factor-binding protein 7 (IGFBP7) is a secreted protein of a family of low-affinity IGF-binding proteins termed "IGFBP-related proteins" that have been identified as a potential tumor suppressor in HCC. IGFBP7 has been implicated in regulating cellular proliferation, senescence, and angiogenesis. In this review, we provide a comprehensive discussion of the role of IGFBP7 in HCC and the potential use of IGFBP7 as a novel biomarker for drug resistance and as an effective therapeutic strategy.

18.
J Biomed Nanotechnol ; 10(12): 3601-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26000373

RESUMO

Multi-walled-carbon nanotubes (MWNTs) are widely explored as carriers for drug delivery due to their facile transport through cellular membranes and are reportedly found to be effective against cancer. In the present study, we have evaluated cellular uptake of Docetaxel (DTX) conjugated MWNTs from human breast cancer cells (MCF-7 and MDA-mb-231) and have provided primary results on cytotoxicity of the same. Efficient internalization of the drug conjugate (DTX-MWNTs) inside the cell was corroborated with the help of confocal microscopy, transmission electron microscopy and flow cytometry. The comparison of cytotoxicity of the conjugate and DTX was done by MTT assay. Results of the study indicated increased efficacy of the conjugates over the drug in terms of their cytotoxicity. It was observed that such conjugation of drug to MWNTs can be explored as a strategy to improve therapeutic index of cytotoxic drugs such as DTX and thereby enriching cancer therapies of coming time.


Assuntos
Neoplasias da Mama/química , Neoplasias da Mama/tratamento farmacológico , Nanocápsulas/química , Nanoconjugados/química , Nanotubos de Carbono/química , Taxoides/administração & dosagem , Taxoides/química , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Docetaxel , Feminino , Humanos , Células MCF-7 , Nanocápsulas/administração & dosagem , Nanocápsulas/ultraestrutura , Nanoconjugados/administração & dosagem , Nanoconjugados/ultraestrutura , Nanotubos de Carbono/ultraestrutura , Tamanho da Partícula , Frações Subcelulares/química , Frações Subcelulares/patologia , Resultado do Tratamento
19.
Mol Ther ; 21(4): 758-66, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23319057

RESUMO

Hepatocellular carcinoma (HCC) is a highly fatal disease mandating development of novel, targeted therapies to elicit prolonged survival benefit to the patients. Insulin-like growth factor-binding protein-7 (IGFBP7), a secreted protein belonging to the IGFBP family, functions as a potential tumor suppressor for HCC. In the present study, we evaluated the therapeutic efficacy of a replication-incompetent adenovirus expressing IGFBP7 (Ad.IGFBP7) in human HCC. Ad.IGFBP7 profoundly inhibited viability and induced apoptosis in multiple human HCC cell lines by inducing reactive oxygen species (ROS) and activating a DNA damage response (DDR) and p38 MAPK. In orthotopic xenograft models of human HCC in athymic nude mice, intravenous administration of Ad.IGFBP7 profoundly inhibited primary tumor growth and intrahepatic metastasis. In a nude mice subcutaneous model, xenografts from human HCC cells were established in both flanks and only left-sided tumors received intratumoral injection of Ad.IGFBP7. Growth of both left-sided injected tumors and right-sided uninjected tumors were markedly inhibited by Ad.IGFBP7 with profound suppression of angiogenesis. These findings indicate that Ad.IGFBP7 might be a potent therapeutic eradicating both primary HCC and distant metastasis and might be an effective treatment option for terminal HCC patients.


Assuntos
Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/terapia , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/terapia , Adenoviridae/genética , Animais , Carcinoma Hepatocelular/genética , Humanos , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/genética , Neoplasias Hepáticas/genética , Masculino , Camundongos , Camundongos Nus , Espécies Reativas de Oxigênio/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Hepatology ; 56(5): 1782-91, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22689379

RESUMO

UNLABELLED: Astrocyte elevated gene-1 (AEG-1) is a key contributor to hepatocellular carcinoma (HCC) development and progression. To enhance our understanding of the role of AEG-1 in hepatocarcinogenesis, a transgenic mouse with hepatocyte-specific expression of AEG-1 (Alb/AEG1) was developed. Treating Alb/AEG-1, but not wild-type (WT) mice, with N-nitrosodiethylamine resulted in multinodular HCC with steatotic features and associated modulation of expression of genes regulating invasion, metastasis, angiogenesis, and fatty acid synthesis. Hepatocytes isolated from Alb/AEG-1 mice displayed profound resistance to chemotherapeutics and growth factor deprivation with activation of prosurvival signaling pathways. Alb/AEG-1 hepatocytes also exhibited marked resistance toward senescence, which correlated with abrogation of activation of a DNA damage response. Conditioned media from Alb/AEG-1 hepatocytes induced marked angiogenesis with elevation in several coagulation factors. Among these factors, AEG-1 facilitated the association of factor XII (FXII) messenger RNA with polysomes, resulting in increased translation. Short interfering RNA-mediated knockdown of FXII resulted in profound inhibition of AEG-1-induced angiogenesis. CONCLUSION: We uncovered novel aspects of AEG-1 functions, including induction of steatosis, inhibition of senescence, and activation of the coagulation pathway to augment aggressive hepatocarcinogenesis. The Alb/AEG-1 mouse provides an appropriate model to scrutinize the molecular mechanism of hepatocarcinogenesis and to evaluate the efficacy of novel therapeutic strategies targeting HCC.


Assuntos
Carcinoma Hepatocelular/genética , Moléculas de Adesão Celular/genética , Transformação Celular Neoplásica/genética , Modelos Animais de Doenças , Neoplasias Hepáticas/genética , Neovascularização Patológica/genética , Animais , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Senescência Celular/genética , Dietilnitrosamina , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Fator XII/genética , Fator XII/metabolismo , Ácidos Graxos/biossíntese , Fígado Gorduroso/genética , Fígado Gorduroso/patologia , Fluoruracila/farmacologia , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Fígado/irrigação sanguínea , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Proteínas de Membrana , Camundongos , Camundongos Transgênicos , Invasividade Neoplásica/genética , Metástase Neoplásica , Análise de Sequência com Séries de Oligonucleotídeos , Polirribossomos , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA
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