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2.
Spinal Cord ; 51(12): 931-3, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24042993

RESUMO

STUDY DESIGN: Spinal tuberculosis as all other osteoarticular tuberculosis occurs as a result of hematogenous dissemination of Mycobacterium tuberculosis from a primarily infected visceral focus mainly lungs, but Pott's paraplegia occurring secondarily to Scrofuloderma has not been reported till date. PURPOSE: To document such an association of Pott's paraplegia and Scrofuloderma. METHODS: A 29-year-old female presented to us with low backache and paraplegia of 1 month duration. Clinical examination showed multiple healed Scrofuloderma lesions over sterum and neck (Figure 1). Magnetic resonance imaging (Figure 4), computed tomography (Figure 3) and X-ray (Figure 2) showed Pott's spine involving dorsal vertebrae (D8-10) with pre and paravetebral abscess with intraspinal extension. She was treated by minimally invasive surgery to drain pus and granulation tissue by resecting transverse process of D9 vertebra. Drained material was sent for histopathological examination, Zielh-neelsen (ZN) staining, culture and sensitivity for M. tuberculosis. Patient completely recovered neurologically after 1 month of surgery. RESULTS: Patient completely recovered neurologically after surgery and is presently on multidrug chemotherapy and spinal brace. CONCLUSIONS: Pott's paraplegia can occur secondary to Scrofuloderma and it can be managed by multidrug antitubercular therapy and minimally invasive surgical procedure.


Assuntos
Mycobacterium tuberculosis/fisiologia , Tuberculose Cutânea/complicações , Tuberculose da Coluna Vertebral/etiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Tomógrafos Computadorizados , Tuberculose da Coluna Vertebral/diagnóstico , Tuberculose da Coluna Vertebral/tratamento farmacológico , Tuberculose da Coluna Vertebral/cirurgia
3.
Cancer Res ; 51(13): 3451-5, 1991 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-2054784

RESUMO

S-phase-active cytotoxic drugs selectively damage leukemic cells, but the mechanisms of this action are not clear. We have investigated the previously reported potentiation of toxicity of 1-beta-D-arabinofuranosylcytosine (ara-C) to HL-60 cells by the differentiation-inducing steroid, 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], and compared the results with the effects of other drugs which inhibit DNA synthesis. Determination of the intracellular content of the active metabolite of ara-C, ara-CTP, excluded more prolonged retention of the drug as the basis for potentiation of cytotoxicity. Alkaline elution of replicating DNA showed that 1,25(OH)2D3 added with or immediately after ara-C or hydroxyurea reduced the rate maturation of the replicating DNA and resulted in an increased proportion of smaller DNA fragments. However, pretreatment of the cells with 1,25(OH)2D3 inhibited this effect of the drugs on replication of DNA. No direct effect of 1,25(OH)2De on replicating DNA could be detected. The results suggest that the early events which initiate cell differentiation may protect an intact DNA replicative machinery from S-phase-active drugs but reduce the rate of DNA maturation once DNA integrity has been compromised by inhibitors of DNA synthesis.


Assuntos
Calcitriol/administração & dosagem , Citarabina/administração & dosagem , Replicação do DNA/efeitos dos fármacos , Arabinofuranosilcitosina Trifosfato/metabolismo , Calcitriol/análogos & derivados , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA , Esquema de Medicação , Sinergismo Farmacológico , Humanos , Relação Estrutura-Atividade , Células Tumorais Cultivadas
4.
Cancer Res ; 52(13): 3636-41, 1992 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-1617636

RESUMO

Human breast cancer cell proliferation is regulated by growth factors that bind to receptors with intrinsic tyrosine kinase (TK) activity, including the epidermal growth factor (EGF) receptor. To determine whether inhibition of receptor TK activity inhibits tumor growth, we studied the effects of a tyrosine kinase inhibitor, RG-13022, on cultured human breast cancer cells. RG-13022 represents a class of compounds which have been shown to inhibit preferentially the TK activity of the EGF receptor in a cell-free system and also to inhibit EGF-stimulated growth of cultured cells. RG-13022 significantly inhibited EGF-stimulated autophosphorylation of its receptor in two breast cancer cell lines that have abundant, although not amplified, EGF receptor content (MDA-231 and T47D). RG-13022 also inhibited EGF-stimulated DNA synthesis and proliferation of T47D and MCF-7 breast cancer cells in a reversible and dose-dependent manner. Inhibition was observed at 0.1 microM, and it was maximal at 10 microM. The effect was rapid (within 3 h), persisted for 18 h, and was partially reversed by 24 h at 1 microM. At 5 microM, inhibition persisted for more than 50 h. Inhibitory effects were also observed in a panel of estrogen receptor-positive and estrogen receptor-negative breast cancer cell lines. RG-13022 inhibited not only EGF-induced growth but also growth stimulated by insulin, insulin-like growth factor I, insulin-like growth factor II, or transforming growth factor alpha. RG-13022 also totally blocked estrogen-stimulated phosphorylation of the EGF receptor, as well as estrogen-induced cell proliferation, suggesting that functioning TK pathways are required for estrogen action. The TK inhibitor RG-13022 is a potent inhibitor of hormonally regulated growth of human breast cancer. Tyrosine kinase inhibitors have the potential of providing a new strategy for the "endocrine therapy" of breast cancer.


Assuntos
Neoplasias da Mama/patologia , Nitrilas/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Piridinas/farmacologia , Tirfostinas , Divisão Celular/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/metabolismo , Estrogênios/farmacologia , Feminino , Humanos , Fosforilação , Células Tumorais Cultivadas/efeitos dos fármacos
5.
Oncogene ; 20(45): 6538-43, 2001 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-11641778

RESUMO

Maspin is a novel serine protease inhibitor (serpin) with tumor suppressive activity. To date, despite the mounting evidence implicating the potential diagnostic/prognostic and therapeutic value of maspin in breast and prostate carcinoma, the lack of a suitable animal model hampers the in vivo investigation on the role of maspin at different stages of tumor progression. In this study, we used MMTV/TGF-alpha transgenic mouse model to study the expression profile of maspin in mammary tumor progression. Histopathological examinations of MMTV/TGF-alpha transgenic mice revealed TGF-alpha expression leading to hyperproliferation, hyperplasia, and occasional carcinoma in mammary gland. Interestingly, when MMTV/TGF-alpha transgenic mice were breed to homozygocity, they also developed characteristic skin papillomas. Immunohistochemistry analysis of maspin expression in the breast tissues of TGF-alpha transgenic mice showed a direct correlation between down-regulation of maspin expression and tumor progression. The loss of maspin expression was concomitant with the critical transition from carcinoma in situ to invasive carcinoma. Subsequent in-situ hybridization analyses suggest that the down-regulation of maspin expression is primarily a transcriptional event. This data is consistent with the tumor suppressive role of maspin. Furthermore, our data suggests that MMTV/TGF-alpha transgenic mouse model is advantageous for in vivo evaluation of both the expression and the biological function of maspin during the slow multi-stage carcinogenesis of mammary gland.


Assuntos
Carcinoma in Situ/metabolismo , Regulação para Baixo , Neoplasias Mamárias Experimentais/metabolismo , Vírus do Tumor Mamário do Camundongo/genética , Biossíntese de Proteínas , Serpinas/biossíntese , Fator de Crescimento Transformador alfa/genética , Animais , Carcinoma in Situ/genética , Carcinoma in Situ/patologia , Progressão da Doença , Feminino , Genes Supressores de Tumor , Hiperplasia/genética , Hiperplasia/metabolismo , Imuno-Histoquímica , Hibridização In Situ , Glândulas Mamárias Animais/metabolismo , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Transgênicos , Invasividade Neoplásica , Proteínas/genética , Proteínas/imunologia , RNA Neoplásico/biossíntese , Serpinas/genética , Serpinas/imunologia , Transcrição Gênica
6.
Oncogene ; 20(31): 4209-18, 2001 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-11464287

RESUMO

We have shown that ER-negative and invasive human breast cancer cell lines MDA-MB-468 and MDA-MB-231 have constitutively higher mitogen activated protein kinase (ERK1&2/MAPK) when compared to the ER-positive and non-invasive MCF-7 human breast cancer cells. In MCF-7 cells, TGFalpha stimulation induced only transient MAPK activation, leading to a transient increase in cell migration. However, MDA 231 and MDA 468 cells, TGFalpha stimulation induced sustained MAPK activation, which correlated with enhanced cell motility and in vitro invasion. Serum stimulation activates ERK/MAPK activity persistently in both ER-positive and ER-negative breast cancer cells, leading to enhanced and sustained cell migration. Inhibition of MAPK activation by anti-sense MEK expression in MDA-MB-468 cells significantly inhibits cell migration and in vitro invasion. In contrast, MCF-7 cells expressing constitutively activated MEK show a significant increase in MAPK activity and cell migration, but this failed to enhance in vitro invasion. The kinetic profiles of MAPK activation and inhibition show a relationship between the duration and magnitude of MAPK activation and cell migration in both ER-positive and ER-negative human breast cancer cells. These studies show that cell motility is modulated by the magnitude and the duration of MAPK activation; but increased activation of MAPK may not be sufficient to allow in vitro invasion in non-invasive MCF-7 breast cancer cells.


Assuntos
Neoplasias da Mama/patologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias da Mama/enzimologia , Neoplasias da Mama/metabolismo , Ativação Enzimática , Humanos , Receptores de Estrogênio/metabolismo , Fator de Crescimento Transformador alfa/farmacologia , Células Tumorais Cultivadas
7.
Int J Radiat Oncol Biol Phys ; 37(5): 1005-10, 1997 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-9169806

RESUMO

PURPOSE: Based on the clinical evidence of mucosal protection by GM-CSF during cytotoxic chemotherapy, a pilot study was undertaken to determine the safety and mucosal reaction of patients receiving GM-CSF while undergoing definitive conventional fractionated radiotherapy in head and neck carcinoma. METHODS AND MATERIALS: Patients were considered eligible if buccal mucosa and oropharynx were included in the teleradiation field. Ten adult patients with squamous cell carcinoma of head and neck (buccal mucosa--8 and posterior 1/3 tongue--2) were entered into the trial. Radiation therapy was delivered with telecobalt machine at conventional 2 Gy fraction and 5 fractions/week. The radiation portals consisted of two parallel opposing lateral fields. GM-CSF was given subcutaneously at a dose of 1 microg/kg body weight, daily, after 20 Gy until the completion of radiation therapy. Patients were evaluated daily for mucosal reaction, pain, and functional impairment. RESULTS: The median radiation dose was 66 Gy. Eight patients received > or = 60 Gy. The tolerance to GM-CSF was good. All 10 patients completed the planned daily dose of GM-CSF without interruption. Mucosal toxicity was Grade I in four patients till the completion of radiotherapy (dose range 50-66 Gy). Six patients developed Grade II reaction, fibrinous mucosal lesions of maximum size 1.0-1.5 cm, during radiotherapy. None developed Grade III mucositis. The maximum mucosal pain was Grade I during GM-CSF therapy. In two patients after starting GM-CSF the pain reduced in intensity. Functional impairment was mild to moderate. All patients were able to maintain adequate oral intake during the treatment period. Total regression of mucosal reaction occured within 8 days following completion of radiotherapy. CONCLUSIONS: GM-CSF administration concurrently with conventional fractionated radiotherapy was feasible without significant toxicity. The acute side effects of radiotherapy namely mucositis, pain, and functional impairment were nil to minimal. The results are suggestive of mucosal protection by GM-CSF during radiotherapy and warrants further study in randomized double blind trial.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Neoplasias de Cabeça e Pescoço/radioterapia , Mucosa Bucal/efeitos da radiação , Estomatite/prevenção & controle , Adulto , Estudos de Viabilidade , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Projetos Piloto , Dosagem Radioterapêutica , Estomatite/etiologia
8.
Mol Cell Endocrinol ; 117(1): 53-8, 1996 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-8734473

RESUMO

In prostate cancer cells, the binding of peptide growth factors to specific receptors increases tyrosine kinases (TK) activity to regulate cell proliferation, cell differentiation, and signaling processes. To determine whether inhibition of receptor TK activity inhibits tumor growth, we studied the effects of a tyrosine kinase inhibitor, RG-13022 (tyrphostin), on cultured human prostate cancer cells. RG-13022 significantly inhibited TGF alpha-induced phosphorylation of EGF receptor (EGFR). This compound inhibited TGF alpha-stimulated [3H]thymidine incorporation in a dose-dependent manner with IC50 being 30 microM. Clonogenicity in soft agar was reduced in the presence of RG-13022. Inhibitory effects were also observed in androgen-positive LNCaP cells and androgen-negative PC3 cells. RG-13022 not only inhibited TGF alpha-induced growth but also growth stimulated by epidermal growth factor (EGF), acidic fibroblast growth factor (aFGF) and serum. In addition, RG-13022 also blocked androgen-stimulated cell proliferation, suggesting that functioning TK pathways are required for androgen-induced growth. This novel synthetic inhibitor may be useful in providing a new strategy for future therapeutic intervention for prostate cancer.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Nitrilas/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Proteínas Tirosina Quinases/antagonistas & inibidores , Piridinas/farmacologia , Tirfostinas , Androgênios/farmacologia , Divisão Celular/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/efeitos dos fármacos , Receptores ErbB/metabolismo , Humanos , Masculino , Fosfatidilinositol 3-Quinases , Fosforilação , Fosfotransferases (Aceptor do Grupo Álcool)/efeitos dos fármacos , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Próstata/enzimologia , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/patologia , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador alfa/farmacologia , Células Tumorais Cultivadas
9.
Int J Oncol ; 15(2): 301-6, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10402241

RESUMO

It is well documented that epidermal growth factor (EGF) inhibits proliferation of A431 and MDA-468 cells via activation of p21/WAF1. In the present study, we have shown that treatment of MDA-468 and A431 cells that express high levels of EGFR with 100 ng/ml of EGF leads to 14.9-fold increase in epidermal growth factor receptor (EGFR) autophosphorylation and high levels of p21/WAF1-induction (6. 7-fold), down regulation of cdk2 activity and growth arrest. When MDA-468 or A431 cells were simultaneously treated with 100 ng/ml EGF and RG13022, a relatively specific tyrosine kinase inhibitor, there was a significant reduction in p21/WAF1 levels. In contrast, when MDA-468, A432 cells that are treated with low levels of EGF (10 ng/ml) or other cells which express low to moderate levels of EGFRs such as MCF-7, MCF-10A, MDA-231 and SKBR-3 breast cells were exposed to 100 ng/ml of EGF there was a 3.8-fold increase in EGFR autophosphorylation, leading to 1.6-fold induction of p21/WAF1 and increased cell proliferation. These results suggest that the level of EGFR tyrosine kinase activity may regulate p21/WAF1 induction in cancer cells.


Assuntos
Ciclinas/biossíntese , Inibidores Enzimáticos/metabolismo , Proteínas de Neoplasias/biossíntese , Proteínas Tirosina Quinases/metabolismo , Divisão Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21 , Proteínas de Ligação a DNA/metabolismo , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/metabolismo , Humanos , Fosforilação , Fator de Transcrição STAT1 , Transdução de Sinais/efeitos dos fármacos , Transativadores/metabolismo , Células Tumorais Cultivadas
10.
Int J Mol Med ; 5(2): 165-71, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10639596

RESUMO

The ubiquitin-mediated proteolytic system has been implicated in the turnover of a number of intracellular proteins. In the present study, we investigated the novelty and potential role of bryostatin 1, a macrocyclic lactone isolated from the marine bryozoan, Bugula neritina, in inducing the ubiquitin-mediated proteolysis of the oncoprotein Bcl-2. Immunoprecipitation and immunoblotting analyses revealed that Bcl-2 is ubiquitinated following exposure of the acute lymphoblastic leukemia (ALL) cell line Reh to 1 nM bryostatin 1. Bcl-2 protein rapidly decreases to 50% of that recorded in the control after 24 h of bryostatin 1 treatment. In the subsequent 24 h, Bcl-2 protein again rapidly decreases to 6% of its pre-bryostatin 1 level at which time a plateau is reached and maintained for another 72 h. Furthermore, ubiquitin-Bcl-2 conjugates are detected in untreated as well as bryostatin 1 treated cells, indicating that ubiquitin-dependent proteolysis plays a role in the normal turnover of Bcl-2. However, ubiquitin-Bcl-2 conjugates increase in a time-dependent manner following bryostatin 1 treatment. Lactacystin, which inhibits the proteinase activities of the proteasome, inhibited the bryostatin 1-induced decrease of Bcl-2 protein. The effect of bryostatin 1 on the proteolytic efficiency of the 26S proteasome in Reh cell extracts was also investigated and shown to increase following 1 h of bryostatin 1 treatment. Proteolytic activity reached its highest point by 3 h, and subsequently returned to control levels by 12 h, post-bryostatin 1 treatment. In addition, bryostatin 1 treatment of the Reh cell line decreased expression of bcl-2 mRNA within 3 h. However, bcl-2 mRNA expression returned after 24 h. We speculate that this decrease in mRNA together with increased 26S proteolytic activity accounts for the initial rapid decrease recorded in Bcl-2 protein. These findings indicate that bryostatin 1 treatment of Reh ALL cells decreases Bcl-2 expression through two processes: a) enhanced Bcl-2 protein degradation through the activation of the ubiquitin-proteasome pathway and b) decreased bcl-2 mRNA expression.


Assuntos
Antineoplásicos/farmacologia , Cisteína Endopeptidases/metabolismo , Lactonas/farmacologia , Complexos Multienzimáticos/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ubiquitinas/metabolismo , Acetilcisteína/análogos & derivados , Acetilcisteína/farmacologia , Northern Blotting , Western Blotting , Briostatinas , Extratos Celulares , Humanos , Macrolídeos , Testes de Precipitina , Leucemia-Linfoma Linfoblástico de Células Precursoras , Complexo de Endopeptidases do Proteassoma , Ligação Proteica , Células Tumorais Cultivadas
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