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1.
J Drugs Dermatol ; 23(1): 1278-1283, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38206145

RESUMO

BACKGROUND: Clascoterone cream 1% is approved for the treatment of acne vulgaris in patients aged 12 years or older based on results from two identical pivotal Phase 3 trials. Integrated efficacy of clascoterone in patients aged 12 years or older with acne vulgaris from the pivotal trials (NCT02608450 and NCT02608476) and long-term extension (LTE) study (NCT02682264) is reported. METHODS: In the pivotal trials, patients with moderate-to-severe acne vulgaris were randomized 1:1 to twice-daily application of clascoterone cream 1% or vehicle for 12 weeks; they could then enter the LTE study, where all patients applied clascoterone to the face and, if desired, trunk for up to 9 additional months. Efficacy was assessed from treatment success based on Investigator's Global Assessment scores (IGA 0/1) in patients aged 12 years or older in the intention-to-treat population; lesion counts were assessed through week 12. Missing data were handled using multiple imputation in the pivotal studies and were not imputed in the LTE study. RESULTS: Of 1421 patients enrolled, 1143 (clascoterone, 576; vehicle, 567) completed week 12; 600 entered and 343 completed the LTE study. The treatment success rate and most lesion count reductions following clascoterone vs placebo treatment reached statistical significance at week 12; the overall treatment success rate increased to 30.2% for facial acne after 12 months and 31.7% for truncal acne after 9 months of treatment. CONCLUSIONS: The efficacy of clascoterone cream 1% for the treatment of acne vulgaris continued to increase over time for up to 12 months in patients aged 12 years or older with acne vulgaris.   J Drugs Dermatol. 2024;23(1):1278-1283.     doi:10.36849/JDD.7719.


Assuntos
Acne Vulgar , Procedimentos de Cirurgia Plástica , Propionatos , Humanos , Acne Vulgar/diagnóstico , Acne Vulgar/tratamento farmacológico , Cortodoxona , Emolientes
2.
Gastroenterology ; 163(1): 295-304.e5, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35304117

RESUMO

BACKGROUND & AIMS: Artificial intelligence (AI) may detect colorectal polyps that have been missed due to perceptual pitfalls. By reducing such miss rate, AI may increase the detection of colorectal neoplasia leading to a higher degree of colorectal cancer (CRC) prevention. METHODS: Patients undergoing CRC screening or surveillance were enrolled in 8 centers (Italy, UK, US), and randomized (1:1) to undergo 2 same-day, back-to-back colonoscopies with or without AI (deep learning computer aided diagnosis endoscopy) in 2 different arms, namely AI followed by colonoscopy without AI or vice-versa. Adenoma miss rate (AMR) was calculated as the number of histologically verified lesions detected at second colonoscopy divided by the total number of lesions detected at first and second colonoscopy. Mean number of lesions detected in the second colonoscopy and proportion of false negative subjects (no lesion at first colonoscopy and at least 1 at second) were calculated. Odds ratios (ORs) and 95% confidence intervals (CIs) were adjusted by endoscopist, age, sex, and indication for colonoscopy. Adverse events were also measured. RESULTS: A total of 230 subjects (116 AI first, 114 standard colonoscopy first) were included in the study analysis. AMR was 15.5% (38 of 246) and 32.4% (80 of 247) in the arm with AI and non-AI colonoscopy first, respectively (adjusted OR, 0.38; 95% CI, 0.23-0.62). In detail, AMR was lower for AI first for the ≤5 mm (15.9% vs 35.8%; OR, 0.34; 95% CI, 0.21-0.55) and nonpolypoid lesions (16.8% vs 45.8%; OR, 0.24; 95% CI, 0.13-0.43), and it was lower both in the proximal (18.3% vs 32.5%; OR, 0.46; 95% CI, 0.26-0.78) and distal colon (10.8% vs 32.1%; OR, 0.25; 95% CI, 0.11-0.57). Mean number of adenomas at second colonoscopy was lower in the AI-first group as compared with non-AI colonoscopy first (0.33 ± 0.63 vs 0.70 ± 0.97, P < .001). False negative rates were 6.8% (3 of 44 patients) and 29.6% (13 of 44) in the AI and non-AI first arms, respectively (OR, 0.17; 95% CI, 0.05-0.67). No difference in the rate of adverse events was found between the 2 groups. CONCLUSIONS: AI resulted in an approximately 2-fold reduction in miss rate of colorectal neoplasia, supporting AI-benefit in reducing perceptual errors for small and subtle lesions at standard colonoscopy. CLINICALTRIALS: gov, Number: NCT03954548.


Assuntos
Adenoma , Pólipos do Colo , Neoplasias Colorretais , Adenoma/diagnóstico por imagem , Adenoma/patologia , Inteligência Artificial , Pólipos do Colo/diagnóstico por imagem , Pólipos do Colo/patologia , Colonoscopia/métodos , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/epidemiologia , Detecção Precoce de Câncer/métodos , Humanos
3.
Mol Cancer Ther ; 19(11): 2256-2266, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32847976

RESUMO

CB-03-10 (cortexolone 17α-valerate-21-propionate) is a synthetic steroidal compound derived from cortexolone (11-deoxycortisone), an intermediate in cortisol biosynthesis. Characterization of the activity of CB-03-10 and its main related compound CB-03-05 (cortexolone 17α-valerate) included in vitro binding to the androgen and glucocorticoid receptors (AR and GR), antagonism of AR and GR transcriptional activities, and screening for antitumor activity across a selected panel of human prostate and in triple-negative breast cancer cell lines. CB-03-10 cytotoxic activity in these cancer cell lines was in the low micromolar range and was primarily associated with induction of the apoptotic cascade via activation of caspases. The compound's potential for antitumor activity was verified in a murine xenograft model utilizing the AR-positive LNCaP prostate cancer cell line as well as in an orthotopic model utilizing AR-negative/GR-positive MDA-MB-231 breast cancer cell line. Orally administered CB-03-10 inhibited prostate tumor growth and orthotopically implanted breast tumor growth in these mice and maintained body weight, as compared with vehicle-treated mice. On the basis of AR/GR binding affinities, antagonism of androgen and glucocorticoid-dependent transcriptional activities, and AR/GR mRNA and protein expression, the mechanism of tumor growth suppression is related to AR and GR antagonist activities. Importantly, these compounds lack biologically relevant AR/GR agonist activities. Overall, these preclinical findings support the selection of CB-03-10 for further development as an anticancer agent in cases where resistance to AR-targeted therapy or chemotherapy, via upregulation of GR activity, continues to limit the efficacy and duration of clinical benefit with these interventions.


Assuntos
Antagonistas de Receptores de Andrógenos/farmacologia , Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Receptores de Glucocorticoides/antagonistas & inibidores , Antagonistas de Receptores de Andrógenos/química , Antagonistas de Receptores de Andrógenos/uso terapêutico , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Biomarcadores , Linhagem Celular Tumoral , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Estrutura Molecular , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Ligação Proteica , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Drug Metab Pharmacokinet ; 34(3): 172-180, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31101589

RESUMO

Rifamycin SV (rifamycin), is a member of the ansamycin family of antimicrobial compounds which kills bacteria commonly associated with infectious diarrhea and other enteric infections. Rifamycin has been found to be effective in experimental animal models of gut inflammation and its efficacy in these settings has been attributed partially to immunomodulatory non-bactericidal activities. This study aimed to further evaluate the anti-inflammatory activities of rifamycin by analyzing its effect on two key regulators of inflammation: PXR and NFκB. Rifamycin stimulated PXR transcriptional activity in two PXR reporter cell lines and induced expression of two genes known to be regulated by PXR and are directly involved in cellular detoxification: CYP3A4 and PgP. Moreover, CYP3A4 metabolic activity was induced by rifamycin in HepG2 cells. Rifamycin also antagonized TNFα and LPS-induced NFκB activities and inhibited IL1ß-induced synthesis of inflammatory chemokine, IL8. Although reciprocal regulation of PXR and NFkB by rifamycin was not directly addressed, the data suggest that in the absence of PXR, inhibition of NFκB by rifamycin is not dependent on PXR stimulation. Thus, rifamycin exhibits potent anti-inflammatory activities, characterized by in vitro PXR activation and concomitant CYP3A4 and PgP induction, in parallel with potent NFκB inhibition and concomitant IL8 inhibition.


Assuntos
Anti-Inflamatórios/farmacologia , NF-kappa B/antagonistas & inibidores , Receptor de Pregnano X/genética , Rifamicinas/farmacologia , Ativação Transcricional/efeitos dos fármacos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Células CACO-2 , Técnicas de Cultura de Células , Citocromo P-450 CYP3A/genética , Células HT29 , Células Hep G2 , Humanos , NF-kappa B/genética , Transdução de Sinais
5.
Biomed Rep ; 2(4): 559-563, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24944808

RESUMO

Butyric acid is a physiological component of the colonic environment that possesses anti-inflammatory and antitumor properties, among others. However, little is known regarding its effects following direct application on the colonic surface. This study was conducted to investigate the topical anti-inflammatory effect of calcium butyrate in chemically-induced colitis in rats and to evaluate its antitumor properties in vivo and in vitro. The anti-inflammatory activity of calcium butyrate was evaluated in dinitrobenzene sulfonic acid-induced colitis in rats, following intracolonic instillation for 6 consecutive days and its in vivo antitumor activity was evaluated in F344 rats with the azoxymethane (AOM)-induced aberrant crypt foci (AFC) test, following intracolonic instillation for 4 weeks. The in vitro antiproliferative activity was assessed by incubation for 48 h with the HT29, SW620 and HCT116 intestinal tumour cell lines to evaluate the rate of 3H-thymidine uptake. In dinitrobenzene-induced colitis, the intracolonic instillation of calcium butyrate completely prevented body weight reduction in the animals and counteracted the local noxious effects of the irritant by reducing colon edema (-22.7%, P=0.048) and the area of mucosal damage (-48%, P=0.045). In the AOM-induced AFC test, the intracolonic instillation of calcium butyrate significantly reduced the number of AFC in the entire colon (-22.7%, P<0.05). Calcium butyrate, following incubation with the HT29, SW620 and HCT116 tumour cell lines, induced a significant antiproliferative, dose-dependent effect (P=0.046 to P=0.002) in all three strains, as measured by the reduction in 3H-thymidine uptake. Calcium butyrate directly applied to the mucosa of the rat colon was able to ameliorate colonic inflammation, suggesting a possible beneficial role in the treatment of inflammatory colon diseases. Moreover, calcium butyrate exhibited notable antitumor effects in vivo and in vitro; however, their clinical relevance requires confirmation by additional clinical investigations.

6.
Gut ; 63(3): 433-41, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23436336

RESUMO

OBJECTIVE: Budesonide MMX is a novel oral formulation of budesonide that uses Multi-Matrix System (MMX) technology to extend release to the colon. This study compared the efficacy of budesonide MMX with placebo in patients with active, mild-to-moderate ulcerative colitis (UC). DESIGN: Patients were randomised 1:1:1:1 to receive budesonide MMX 9 mg or 6 mg, or Entocort EC 9 mg (budesonide controlled ileal-release capsules; reference arm) or placebo once daily for 8 weeks. The primary endpoint was combined clinical and endoscopic remission, defined as UC Disease Activity Index score ≤1 with a score of 0 for rectal bleeding and stool frequency, no mucosal friability on colonoscopy, and a ≥1-point reduction in endoscopic index score from baseline. RESULTS: 410 patients were evaluated for efficacy. Combined clinical and endoscopic remission rates with budesonide MMX 9 mg or 6 mg, Entocort EC and placebo were 17.4%, 8.3%, 12.6% and 4.5%, respectively. The difference between budesonide MMX 9 mg and placebo was significant (OR 4.49; 95% CI 1.47 to 13.72; p=0.0047). Budesonide MMX 9 mg was associated with numerically higher rates of clinical (42.2% vs 33.7%) and endoscopic improvement (42.2% vs 31.5%) versus placebo. The rate of histological healing (16.5% vs 6.7%; p=0.0361) and proportion of patients with symptom resolution (23.9% vs 11.2%; p=0.0220) were significantly higher for budesonide MMX 9 mg than placebo. Adverse event profiles were similar across groups. CONCLUSION: Budesonide MMX 9 mg was safe and more effective than placebo at inducing combined clinical and endoscopic remission in patients with active, mild-to-moderate UC.


Assuntos
Anti-Inflamatórios/administração & dosagem , Budesonida/administração & dosagem , Colite Ulcerativa/tratamento farmacológico , Quimioterapia de Indução/métodos , Administração Oral , Adolescente , Adulto , Idoso , Anti-Inflamatórios/uso terapêutico , Budesonida/uso terapêutico , Preparações de Ação Retardada , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Análise de Intenção de Tratamento , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
7.
Int J Antimicrob Agents ; 42(2): 182-6, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23756321

RESUMO

There have been several reports showing convincing evidence for non-bactericidal activities of the rifamycin antibiotics. In particular, the parent compound rifamycin SV has been employed in a limited number of cases to treat rheumatoid arthritis. Moreover, rifamycin SV and its derivative rifaximin have been found to be effective in experimental animal models of gut inflammation. The efficacy of rifamycin SV and rifaximin in these settings has been attributed partially to indirect non-bactericidal activities. To better clarify the mechanisms by which these two antibiotics exert their non-bactericidal effects, their activities were compared in in vitro cellular models of immunomodulation and inflammation. Both antibiotics were found to inhibit cytokine and chemokine synthesis from lipopolysaccharide-activated THP-1 monocytes and macrophages. It was also demonstrated, for the first time, that rifamycin SV exerts anti-inflammatory activities in HT-29 colonic epithelial cells. Moreover, rifamycin SV is also very effective in downregulating secretion of inflammatory cytokines from human CD4 T-cells. In general, both antibiotics show similar activities on all four cell types tested. However, rifamycin SV is less cytotoxic than rifaximin when tested in these cells.


Assuntos
Anti-Inflamatórios/farmacologia , Fatores Imunológicos/farmacologia , Rifamicinas/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linhagem Celular , Citocinas/metabolismo , Células Epiteliais/efeitos dos fármacos , Humanos , Macrófagos/efeitos dos fármacos , Monócitos/efeitos dos fármacos
8.
J Proteomics ; 74(7): 1113-22, 2011 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-21504803

RESUMO

Nitrogen-containing bisphosphonates (N-BPs) are therapeutic agents used to treat osteoporosis and promote osteoblast and osteocyte survival. The molecular mechanisms underlying this effect have been extensively studied, but the global changes induced by N-BPs at the protein level are not known. In this context, we investigated the effect of 10(-7)M Risedronate for 1h and 48h on MLO-Y4 osteocytic cells, through a quantitative, label free shotgun proteomic analysis. We described herein a preliminary proteome map of untreated MLO-Y4 cells, composed of 353 protein species. Moreover, we identified 10 and 15 differentially expressed proteins after 1h and 48h of Risedronate treatment, respectively. Among these, PARK7/DJ-1 protein levels were induced up to 3 times and this event was associated with the activation of the pro-survival Akt pathway that we propose as a novel player in the effect of N-BPs on osteocytes. Risedronate was also able to induce the expression and the secretion of the growth factor pro-granulin. In addition, protein prenylation inhibition appeared to be involved in the modulation of MLO-Y4 proteome by RIS in a protein-specific manner. In conclusion, these findings unveil novel functions targeted by N-BPs in osteocytes and could be useful to design novel pharmaceutical compounds.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Ácido Etidrônico/análogos & derivados , Osteócitos/efeitos dos fármacos , Animais , Western Blotting , Difosfonatos/farmacologia , Ácido Etidrônico/farmacologia , Perfilação da Expressão Gênica , Camundongos , Prenilação de Proteína/efeitos dos fármacos , Proteômica/métodos , Proteínas Proto-Oncogênicas c-akt/fisiologia , Ácido Risedrônico , Espectrometria de Massas em Tandem
9.
Genome Biol ; 10(9): R93, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19744312

RESUMO

BACKGROUND: Nitrogen-containing bisphosphonates are the elected drugs for the treatment of diseases in which excessive bone resorption occurs, for example, osteoporosis and cancer-induced bone diseases. The only known target of nitrogen-containing bisphosphonates is farnesyl pyrophosphate synthase, which ensures prenylation of prosurvival proteins, such as Ras. However, it is likely that the action of nitrogen-containing bisphosphonates involves additional unknown mechanisms. To identify novel targets of nitrogen-containing bisphosphonates, we used a genome-wide high-throughput screening in which 5,936 Saccharomyces cerevisiae heterozygote barcoded mutants were grown competitively in the presence of sub-lethal doses of three nitrogen-containing bisphosphonates (risedronate, alendronate and ibandronate). Strains carrying deletions in genes encoding potential drug targets show a variation of the intensity of their corresponding barcodes on the hybridization array over the time. RESULTS: With this approach, we identified novel targets of nitrogen-containing bisphosphonates, such as tubulin cofactor B and ASK/DBF4 (Activator of S-phase kinase). The up-regulation of tubulin cofactor B may explain some previously unknown effects of nitrogen-containing bisphosphonates on microtubule dynamics and organization. As nitrogen-containing bisphosphonates induce extensive DNA damage, we also document the role of DBF4 as a key player in nitrogen-containing bisphosphonate-induced cytotoxicity, thus explaining the effects on the cell-cycle. CONCLUSIONS: The dataset obtained from the yeast screen was validated in a mammalian system, allowing the discovery of new biological processes involved in the cellular response to nitrogen-containing bisphosphonates and opening up opportunities for development of new anticancer drugs.


Assuntos
Proteínas de Ciclo Celular/genética , Difosfonatos/farmacologia , Mutação , Saccharomyces cerevisiae/genética , Alendronato/farmacologia , Western Blotting , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/ultraestrutura , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Divisão Celular/efeitos dos fármacos , Divisão Celular/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Quebras de DNA de Cadeia Dupla , Dano ao DNA , Ácido Etidrônico/análogos & derivados , Ácido Etidrônico/farmacologia , Deleção de Genes , Humanos , Ácido Ibandrônico , Microscopia Confocal , Microscopia Eletrônica , Microtúbulos/efeitos dos fármacos , Microtúbulos/metabolismo , Fosfatos de Poli-Isoprenil/farmacologia , Interferência de RNA , Ácido Risedrônico , Saccharomyces cerevisiae/crescimento & desenvolvimento , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
10.
Bone ; 39(4): 739-53, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16697713

RESUMO

Bisphosphonates are the most important drugs used in the treatment of osteoporosis as they inhibit osteoclast resorption and stimulate proliferation of osteoblasts. However, the molecular mechanisms responsible for these effects are still poorly elucidated. It is known that nucleotide receptors-mediated signaling plays a central role in modulating osteoblasts growth in response to mechanical stress. By using osteoblast-like cell lines (i.e., HOBIT, MG-63, ROS P2Y), which express P2Y receptors, we found that the treatment with risedronate promotes non-lytic ATP release leading to activation of ERKs through the involvement of P2Y receptors triggering. A major role in this signal transduction pathway seems to be the involvement of P2Y(1) and P2Y(2) receptors, since the stimulatory effect of risedronate on ERKs is not appreciable in ROS 17/2.8 cells, which do not express these two receptors. Differential proteomics analysis identified Hsp90 upregulation as a result of risedronate effect on HOBIT and MG-63 cells. The stimulatory effect is dependent on ERKs activation involving nucleotide receptors triggering and leads to increased proliferation of osteoblast-like cells. In fact, functional inactivation of Hsp90 by the specific inhibitor 17-AAG prevents the bisphosphonate-induced mitogenic effects in osteoblasts. These findings show that bisphosphonates, by inducing ATP release, may also act through nucleotide receptors signaling leading to ERKs activation and may exert their mitogenic role on osteoblasts through the involvement of Hsp90.


Assuntos
Difosfonatos/farmacologia , Proteínas de Choque Térmico HSP90/metabolismo , Osteoblastos/efeitos dos fármacos , Receptores Purinérgicos P2/fisiologia , Transdução de Sinais/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Alendronato/farmacologia , Apirase/farmacologia , Western Blotting , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ácido Etidrônico/análogos & derivados , Ácido Etidrônico/farmacologia , Humanos , Espectrometria de Massas , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Modelos Biológicos , Osteoblastos/metabolismo , Ácido Risedrônico , Suramina/farmacologia
11.
Bone ; 36(3): 418-32, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15777650

RESUMO

Dynamic mechanical loading increases bone density and strength and promotes osteoblast proliferation, differentiation and matrix production, by acting at the gene expression level. Molecular mechanisms through which mechanical forces are conversed into biochemical signalling in bone are still poorly understood. A growing body of evidence point to extracellular nucleotides (i.e., ATP and UTP) as soluble factors released in response to mechanical stimulation in different cell systems. Runx2, a fundamental transcription factor involved in controlling osteoblasts differentiation, has been recently identified as a target of mechanical signals in osteoblastic cells. We tested the hypothesis that these extracellular nucleotides could be able to activate Runx2 in the human osteoblastic HOBIT cell line. We found that ATP and UTP treatments, as well as hypotonic stress, promote a significant stimulation of Runx2 DNA-binding activity via a mechanism involving PKC and distinct mitogen-activated protein kinase cascades. In fact, by using the specific inhibitors SB203580 (specific for p38 MAPK) and PD98059 (specific for ERK-1/2 MAPK), we found that ERK-1/2, but not p38, play a major role in Runx2 activation. On the contrary, another important transcription factor, i.e., Egr-1, that we previously demonstrated being activated by extracellular released nucleotides in this osteoblastic cell line, demonstrated to be susceptible to both ERK-1/2 and p38 kinases. These data suggest a possible differential involvement of these two transcription factors in response to extracellularly released nucleotides. The biological relevance of our data is strengthened by the finding that a target gene of Runx2, i.e., Galectin-3, is up-regulated by ATP stimulation of HOBIT cells with a comparable kinetic of that found for Runx2. Since it is known that osteocytes are the primary mechanosensory cells of the bone, we hypothesize that they may signal mechanical loading to osteoblasts through release of extracellular nucleotides. Altogether, these data suggest a molecular mechanism explaining the purinoreceptors-mediated activation of specific gene expression in osteoblasts and could be of help in setting up new pharmacological strategies for the intervention in bone loss pathologies.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Líquido Extracelular/fisiologia , Oligodesoxirribonucleotídeos/farmacologia , Osteoblastos/metabolismo , Fatores de Transcrição/metabolismo , Trifosfato de Adenosina/farmacologia , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core , Citoplasma/efeitos dos fármacos , Citoplasma/metabolismo , Proteínas de Ligação a DNA/genética , Líquido Extracelular/efeitos dos fármacos , Humanos , Oligodesoxirribonucleotídeos/metabolismo , Osteoblastos/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Estresse Mecânico , Transativadores/fisiologia , Fator de Transcrição AP-2 , Fatores de Transcrição/genética , Uridina Trifosfato/farmacologia
12.
Free Radic Res ; 39(3): 269-81, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15788231

RESUMO

The Early Growth Response protein (Egr-1) is a C(2)H(2)-zinc finger-containing transcriptional regulator involved in the control of cell proliferation and apoptosis. Its DNA-binding activity is redox regulated in vitro through the oxidation-reduction of Cys residues within its DNA-binding domain. APE/Ref-1 is a DNA-repair enzyme with redox modulating activities on several transcription factors. In this study, by evaluating the effects of different stimuli, we found a similar timing of activation being suggestive for a common and co-linear regulation for the two proteins. Indeed, we show that APE/Ref-1 increases the Egr-1 DNA-binding activity in unstimulated osteoblastic HOBIT cells. H(2)O(2) stimulation induces a strong interaction between Egr-1 and APE/Ref-1 at early times upon activation, as assayed by immunoprecipitation experiments. By using a cell transfection approach, we demonstrated the functional role of this interaction showing that two specific Egr-1 target genes, the PTEN phosphatase and the thymidine kinase (TK) genes promoters, are activated by contransfection of APE/Ref-1. Interestingly, by using a cell transfection approach and Chromatin immunoprecipitation assays, we were able to demonstrate that Egr-1 stimulates the transcriptional activity of APE/Ref-1 gene promoter by a direct interaction with specific DNA-binding site on its promoter. Taken together, our data delineate a new molecular mechanism of Egr-1 activation occurring soon after H(2)O(2) stimulation in osteoblastic cells and suggest a model for a positive loop between APE/Ref-1 and Egr-1 that could explain the early transcriptional activation of APE/Ref-1 gene expression.


Assuntos
DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Proteínas Imediatamente Precoces/metabolismo , Osteoblastos , Estresse Oxidativo , Fatores de Transcrição/metabolismo , Sequência de Bases , Sítios de Ligação , Linhagem Celular , Proliferação de Células , Imunoprecipitação da Cromatina , DNA/metabolismo , Reparo do DNA , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , Proteínas de Ligação a DNA/genética , Proteína 1 de Resposta de Crescimento Precoce , Ensaio de Desvio de Mobilidade Eletroforética , Humanos , Peróxido de Hidrogênio/farmacologia , Proteínas Imediatamente Precoces/genética , Dados de Sequência Molecular , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Oxidantes/farmacologia , Oxirredução , PTEN Fosfo-Hidrolase , Monoéster Fosfórico Hidrolases/genética , Monoéster Fosfórico Hidrolases/metabolismo , Regiões Promotoras Genéticas/genética , Timidina Quinase/genética , Timidina Quinase/metabolismo , Fatores de Transcrição/genética , Transcrição Gênica , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Dedos de Zinco
13.
Arzneimittelforschung ; 54(12): 881-6, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15646372

RESUMO

The aim of this study was to investigate the antiandrogenic activity of a new monoester of cortexolone, cortexolone 17alpha-propionate (CAS 19608-29-8, CB-03-01). Although the compound displayed a strong local antiandrogenic activity in hamster's flank organ test, it did not exhibit antiandrogenic activity in rats after subcutaneous injection, nor did it affect gonadotropins hypersecretion when injected to parabiotic rats. As topical antiandrogen, the steroid resulted about 4 times more active than progesterone (CAS 57-83-0) and, when compared to known antiandrogen standards, it was about 3 times more potent than flutamide (CAS 13311-84-7), about 2 times more effective than finasteride (CAS 98319-26-7) and approximately as active as cyproterone acetate (CAS 427-51-0). Its pharmacological activity seemed to be primarily related to its ability to antagonistically compete at androgen receptor level; nevertheless its primary pharmacological target needs to be further investigated. Its topical activity, along with the apparent absence of systemic effects, anticipates this compound to have the potential of representing a novel and safe therapeutic approach for androgen-dependent skin disorders.


Assuntos
Antagonistas de Androgênios/farmacologia , Cortodoxona/análogos & derivados , Cortodoxona/farmacologia , Propionatos/farmacologia , Administração Tópica , Antagonistas de Androgênios/toxicidade , Animais , Corticosterona/sangue , Cortodoxona/toxicidade , Cricetinae , Feminino , Glucocorticoides/antagonistas & inibidores , Gonadotropinas/metabolismo , Injeções Intravenosas , Masculino , Mesocricetus , Orquiectomia , Progesterona/sangue , Propionatos/toxicidade , Ratos , Ratos Wistar , Propionato de Testosterona/antagonistas & inibidores , Propionato de Testosterona/farmacologia
14.
Biochem J ; 373(Pt 3): 815-24, 2003 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-12729460

RESUMO

Extracellular nucleotides exert an important role in controlling cell physiology by activating intracellular signalling cascades. Osteoblast HOBIT cells express P2Y(1) and P2Y(2) G-protein-coupled receptors, and respond to extracellular ATP by increasing cytosolic calcium concentrations. Early growth response protein 1 (Egr-1) is a C(2)H(2)-zinc-finger-containing transcriptional regulator responsible for the activation of several genes involved in the control of cell proliferation and apoptosis, and is thought to have a central role in osteoblast biology. We show that ATP treatment of HOBIT cells increases Egr-1 protein levels and binding activity via a mechanism involving a Ca(2+)-independent protein kinase C isoform. Moreover, hypotonic stress and increased medium turbulence, by inducing ATP release, result in a similar effect on Egr-1. Increased levels of Egr-1 protein expression and activity are achieved at very early times after stimulation (5 min), possibly accounting for a rapid way for changing the osteoblast gene-expression profile. A target gene for Egr-1 that is fundamental in osteoblast physiology, COL1A2, is up-regulated by ATP stimulation of HOBIT cells in a timescale that is compatible with that of Egr-1 activation.


Assuntos
Trifosfato de Adenosina/farmacologia , Proteínas de Ligação a DNA/metabolismo , Proteínas Imediatamente Precoces , Osteoblastos/efeitos dos fármacos , Proteína Quinase C/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Bases , Linhagem Celular , Colágeno/genética , Colágeno Tipo I , Primers do DNA , Proteína 1 de Resposta de Crescimento Precoce , Ensaio de Desvio de Mobilidade Eletroforética , Humanos , Osteoblastos/enzimologia , Osteoblastos/metabolismo , Estresse Mecânico
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