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1.
Front Cell Dev Biol ; 10: 991330, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36158198

RESUMO

The most common type of cancer in the present-day world affecting modern-day men after lung cancer is prostate cancer. Prostate cancer remains on the list of top three cancer types claiming the highest number of male lives. An estimated 1.4 million new cases were reported worldwide in 2020. The incidence of prostate cancer is found predominantly in the regions having a high human development index. Despite the fact that considerable success has been achieved in the treatment and management of prostate cancer, it remains a challenge for scientists and clinicians to curve the speedy advancement of the said cancer type. The most common risk factor of prostate cancer is age; men tend to become more vulnerable to prostate cancer as they grow older. Commonly men in the age group of 66 years and above are the most vulnerable population to develop prostate cancer. The gulf countries are not far behind when it came to accounting for the number of individuals falling prey to the deadly cancer type in recent times. There has been a consistent increase in the incidence of prostate cancer in the gulf countries in the past decade. The present review aims at discussing the development, diagnostics via machine learning, and implementation of treatment of prostate cancer with a special focus on nanotherapeutics, in the gulf countries.

2.
Med Oncol ; 29(2): 1384-90, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21499927

RESUMO

Cancer cells are aided by immune-tolerant functions of HLA-G to escape the immune surveillance. In general, cancer cells can express membranous HLA-G, secrete soluble HLA-G, produce HLA-G positive exosomes, and can be subjected to proteolytic cleavage by matrix metalloproteinases releasing shedding HLA-G1 in stressful conditions. Thus, the downregulation of HLA-G either in transcripts or proteins may affect positively cancer therapy. The aim of this study was to examine the molecular nanoparticles targeting HLA-G. Special focus was accorded to RNA interference particles. Although numerous studies have reported the importance of HLA-G gene expression modulation by nanoparticles, no studies have investigated clinically their efficiency in this modulation.


Assuntos
Terapia Genética , Antígenos HLA-G/química , Antígenos HLA-G/genética , Nanopartículas , Neoplasias/genética , Neoplasias/terapia , Humanos , Prognóstico
4.
Tumour Biol ; 32(6): 1071-86, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21792710

RESUMO

HLA-G is unique among the class I human leukocyte antigens. It plays a pivotal role in immune tolerance and a paradoxical role in therapies. Indeed, HLA-G expression is associated with a good prognosis in organ transplantation and an ominous prognosis in cancer. Recent progress has been made in HLA-G regulation identification, especially on human cell lines; however, little is known about their role in cancer therapy. Based on the role of HLA-G expression in cancer, we investigated the potential impact of the regulation of this expression on the outcome of some cancers. In this communication, we emphasize the importance of screening for HLA-G expression after cancer therapy. Future clinical trials could lead to a better understanding of the implication of HLA-G expression in cancer and lead to a better knowledge of cancer monitoring and recurrence. These studies could also implicate HLA-G as a therapeutic target in cancer therapy.


Assuntos
Antineoplásicos/uso terapêutico , Antígenos HLA-G/imunologia , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/imunologia , Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Antígenos HLA-G/genética , Antígenos HLA-G/metabolismo , Humanos , Neoplasias/genética , Prognóstico
5.
Med Hypotheses ; 77(1): 134-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21507579

RESUMO

HLA-G, a very conserved non-classical class I human leukocyte antigen, is highly expressed in cancer pathologies. Recent evidences about HLA-G implication in immune tolerance announce the probable association between HLA-G and metastasis. We highlighted here possible mechanisms for link between HLA-G regulation and cascade metastasis including initiation, progression, and virulence steps. A thorough understanding of HLA-G implications in metastasis through future clinical studies, may probably lead to the improvement of cancer therapies and the limitation of relapses and metastasis.


Assuntos
Antígenos HLA/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Metástase Neoplásica/imunologia , Antígenos HLA-G , Humanos
6.
Med Oncol ; 28(2): 641-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20373059

RESUMO

Malignancy is one of the comorbidities linked to golimumab, a biological TNF-α blocker. In this systematic review and meta-analysis, we searched different databases and analyzed original publications to elucidate the remaining open question about the real association of malignancies with golimumab therapy. The most frequent cancer in patients treated with golimumab, in association or not with methotrexate, is the lung adenocarcinoma. However, lymphoma is not very commonly represented in these patients. We show that there is no major and evident risk of malignancies associated with golimumab in current scientific literature. An increased risk of malignancies may be associated with golimumab, but this warrants further clinical confirmation. Also, this risk mentioned in different studies must be taken with caution because of number of limits and biases.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Antirreumáticos/efeitos adversos , Neoplasias/induzido quimicamente , Artrite Reumatoide/tratamento farmacológico , Humanos , Metotrexato/uso terapêutico
7.
J Med Chem ; 50(16): 3937-44, 2007 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-17602466

RESUMO

Cinnamtannin B-1, a natural A-type proanthocyanidin recently identified as a radical scavenger component of Laurus nobilis L., exerts antiaggregant and antiapoptotic effects in human platelets. Here, we have investigated the intracellular mechanisms involved in the antiaggregant effects of cinnamtannin B-1. Cinnamtannin B-1 showed a greater free radical scavenging activity than vitamin C, vitamin E, or Trolox, among other antioxidants and reduced thrombin-evoked tubulin reorganization and platelet aggregation. Thrombin-evoked activation of Btk and pp60(src) was also inhibited by cinnamtannin B-1. In conclusion, we show that cinnamtannin B-1 is a powerful oxygen radical scavenger that reduces thrombin-evoked microtubular remodeling and activation of the tyrosine kinases Btk and pp60(src), which leads to inhibition of platelet aggregation. These observations suggest that cinnamtannin B-1 may prevent thrombotic complications associated to platelet hyperaggregability and hyperactivity, although further studies are necessary to establish appropriate therapeutic strategies.


Assuntos
Antocianinas/farmacologia , Sequestradores de Radicais Livres/farmacologia , Laurus , Inibidores da Agregação Plaquetária/farmacologia , Tirosina Quinase da Agamaglobulinemia , Cálcio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Ativação Enzimática , Humanos , Técnicas In Vitro , Microtúbulos/efeitos dos fármacos , Fosforilação , Proantocianidinas , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Trombina/metabolismo , Tirosina/metabolismo
8.
Arch Biochem Biophys ; 465(1): 16-25, 2007 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-17543880

RESUMO

Thrombin induces platelet activation through a variety of intracellular mechanisms, including Ca(2+) mobilization. The protein of the exocytotic machinery SNAP-25, but not VAMPs, is required for store-operated Ca(2+) entry, the main mechanism for Ca(2+) influx in platelets. Hence, we have investigated the role of the SNAP-25 and VAMPs in thrombin-induced platelet aggregation. Platelet stimulation with thrombin or selective activation of thrombin receptors PAR-1, PAR-4 or GPIb-IX-V results in platelet aggregation that, except for GPIb-IX-V receptor, requires Ca(2+) entry for full activation. Depletion of the intracellular Ca(2+) stores using pharmacological tools was unable to induce aggregation except when cytosolic Ca(2+) concentration reached a critical level (around 1.5 microM). Electrotransjection of cells with anti-SNAP-25 antibody reduced thrombin-evoked platelet aggregation, while electrotransjection of anti-VAMP-1, -2 and -3 antibody had no effect. These findings support a role for SNAP-25 but not VAMP-1, -2 and -3 in platelet aggregation, which is likely mediated by the regulation of Ca(2+) mobilization in human platelets.


Assuntos
Citoesqueleto de Actina/metabolismo , Plaquetas/fisiologia , Cálcio/metabolismo , Agregação Plaquetária/fisiologia , Proteínas SNARE/metabolismo , Transdução de Sinais/fisiologia , Trombina/administração & dosagem , Plaquetas/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , Agregação Plaquetária/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
9.
Biochem J ; 401(1): 167-74, 2007 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-16939417

RESUMO

Physiological agonists increase cytosolic free Ca2+ concentration to regulate a number of cellular processes. The platelet thrombin receptors, PAR (protease-activated receptor) 1 PAR-4 and GPIb-IX-V (glycoprotein Ib-IX-V) have been described as potential contributors of thrombin-induced platelet aggregation. Platelets present two separate Ca2+ stores, the DTS (dense tubular system) and acidic organelles, differentiated by the distinct sensitivity of their respective SERCAs (sarcoplasmic/endoplasmic-reticulum Ca2+-ATPases) to TG (thapsigargin) and TBHQ [2,5-di-(tert-butyl)-1,4-hydroquinone]. However, the involvement of the thrombin receptors in Ca2+ release from each Ca2+ store remains unknown. Depletion of the DTS using ADP, which releases Ca2+ solely from the DTS, in combination with 10 nM TG, to selectively inhibit SERCA2 located on the DTS reduced Ca2+ release evoked by the PAR-1 agonist, SFLLRN, and the PAR-4 agonist, AYPGKF, by 80 and 50% respectively. Desensitization of PAR-1 and PAR-4 or pre-treatment with the PAR-1 and PAR-4 antagonists SCH 79797 and tcY-NH2 reduced Ca2+ mobilization induced by thrombin, and depletion of the DTS after desensitization or blockade of PAR-1 and PAR-4 had no significant effect on Ca2+ release stimulated by thrombin through the GPIb-IX-V receptor. Converse experiments showed that depletion of the acidic stores using TBHQ reduced Ca2+ release evoked by SFLLRN or AYPGKF, by 20 and 50% respectively, and abolished thrombin-stimulated Ca2+ release through the GPIb-IX-V receptor when PAR-1 and PAR-4 had been desensitized or blocked. Our results indicate that thrombin-induced activation of PAR-1 and PAR-4 evokes Ca2+ release from both Ca2+ stores, while activation of GPIb-IX-V by thrombin releases Ca2+ solely from the acidic compartments in human platelets.


Assuntos
Plaquetas/fisiologia , Cálcio/sangue , Receptores de Trombina/fisiologia , Plaquetas/citologia , Sobrevivência Celular , Citosol/fisiologia , Humanos , Cinética , Receptores de Trombina/sangue , Trombina/fisiologia
10.
J Physiol ; 570(Pt 2): 309-23, 2006 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-16308346

RESUMO

A major pathway for Ca(2+) entry in non-excitable cells is activated following depletion of intracellular Ca(2+) stores. A de novo conformational coupling between elements in the plasma membrane (PM) and Ca(2+) stores has been proposed as the most likely mechanism to activate this capacitative Ca(2+) entry (CCE) in several cell types, including platelets. Here we report that a cytochrome P450 metabolite, 5,6-EET, might be a component of the de novo conformational coupling in human platelets. In these cells, 5,6-EET induces divalent cation entry without having any detectable effect on Ca(2+) store depletion. 5,6-EET-induced Ca(2+) entry was sensitive to the CCE blockers 2-APB, lanthanum, SKF-96365 and nickel and impaired by incubation with anti-hTRPC1 antibody. Ca(2+) entry stimulated by low concentrations of thapsigargin, which selectively depletes the dense tubular system and induces EET production, was impaired by the cytochrome P450 inhibitor 17-ODYA, which has no effect on CCE mediated by depletion of the acidic stores using 2,5-di-(tert-butyl)-1,4-hydroquinone. We have found that 5,6-EET-induced Ca(2+) entry requires basal levels of H(2)O(2), which might maintain a redox state favourable for this event. Finally, our results indicate that 5,6-EET induces the activation of tyrosine kinase proteins and the reorganization of the actin cytoskeleton, which might provide a support for the transport of portions of the Ca(2+) store towards the PM to facilitate de novo coupling between IP(3)R type II and hTRPC1 detected by coimmunoprecipitation. We propose that the involvement of 5,6-EET in TG-induced coupling between IP(3)R type II and hTRPC1 and subsequently CCE is compatible with the de novo conformational coupling in human platelets.


Assuntos
Ácido 8,11,14-Eicosatrienoico/análogos & derivados , Plaquetas/metabolismo , Cálcio/metabolismo , Permeabilidade da Membrana Celular , Membrana Celular/fisiologia , Ácido 8,11,14-Eicosatrienoico/farmacologia , Actinas/análise , Actinas/fisiologia , Anticorpos/imunologia , Anticorpos/farmacologia , Compostos de Boro/farmacologia , Canais de Cálcio/fisiologia , Membrana Celular/química , Permeabilidade da Membrana Celular/efeitos dos fármacos , Citocalasina D/farmacologia , Sistema Enzimático do Citocromo P-450/fisiologia , Citoesqueleto/química , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/fisiologia , Ativação Enzimática , Humanos , Peróxido de Hidrogênio/farmacologia , Imidazóis/farmacologia , Receptores de Inositol 1,4,5-Trifosfato , Lantânio/farmacologia , Manganês/metabolismo , Níquel/farmacologia , Proteínas Tirosina Quinases/metabolismo , Receptores Citoplasmáticos e Nucleares/fisiologia , Canais de Cátion TRPC/imunologia , Canais de Cátion TRPC/fisiologia , Tapsigargina/farmacologia
11.
Cell Signal ; 18(8): 1252-61, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16300929

RESUMO

Platelets express, among others, initiator caspase 9 and effector caspase 3. Upon activation by physiological agonists, calcium ionophores or under shear stress they might develop apoptotic events. Although it is well known that the cytoskeletal network plays a crucial role in apoptosis, the relationship between caspases 3 and 9 and the cytoskeleton is poorly understood. Here we demonstrate that the physiological agonist thrombin is able to induce activation of caspases 3 and 9 in human platelets and significantly increases the amount in the cytoskeleton of the active forms of both caspases and the procaspases 3 and 9. After stimulation with thrombin the amount of active caspases 3 and 9 in the cytosolic and cytoskeletal fractions were significantly reduced in Ro-31-8220-treated cells, which demonstrates that caspases activation and association with the cytoskeleton needs the contribution of PKC. Inhibition of actin polymerization by cytochalasin D inhibits translocation and activation of both caspases, suggesting that thrombin stimulates caspase 3 and 9 activation and association with the reorganizing actin cytoskeleton. Finally, our results show that inhibition of thrombin-induced caspase activation has no effect on their translocation to the cytoskeleton although impairment of thrombin-evoked caspase translocation has negative effects on caspase activity, suggesting that translocation to the cytoskeleton might be important for caspase activation by thrombin in human platelets.


Assuntos
Citoesqueleto de Actina/enzimologia , Plaquetas/efeitos dos fármacos , Plaquetas/enzimologia , Caspases/metabolismo , Proteína Quinase C/metabolismo , Trombina/farmacologia , Biopolímeros , Caspase 3 , Caspase 9 , Inibidores de Caspase , Citocalasina D/farmacologia , Citosol/enzimologia , Ativação Enzimática/efeitos dos fármacos , Humanos , Transporte Proteico/efeitos dos fármacos
12.
Cell Signal ; 17(8): 1011-21, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15894173

RESUMO

Store-mediated Ca(2+) entry (SMCE), which is rapidly activated by depletion of the intracellular Ca(2+) stores, is a major mechanism for Ca(2+) influx. Several studies have involved tyrosine kinases in the activation of SMCE, such as pp60(src), although at present those involved in the early activation steps are unknown. Here we report the involvement of Bruton's tyrosine kinase (Btk) in the early stages of SMCE in human platelets. Cell treatment with thrombin or thapsigargin (TG) plus ionomycin (Iono) results in rapid activation of Btk, which was independent of rise in intracellular Ca(2+) concentration ([Ca(2+)](i)) but dependent on H(2)O(2) generation. Platelet treatment with Btk inhibitors, LFM-A13 or terreic acid, significantly reduced TG+Iono- and thrombin-evoked SMCE. Btk was rapidly activated by addition of low concentrations of H(2)O(2), whose effect on Ca(2+) entry was prevented by Btk inhibitors. Our results indicate that pp60(src) and Btk co-immunoprecipitate after platelet stimulation with TG+Iono, thrombin or H(2)O(2). In addition, we have found that LFM-A13 impaired actin filament reorganization after store depletion and agonist-induced activation of pp60(src), while the inhibitor of pp60(src), a protein that requires actin reorganization for its activation, did not modify Btk activation, suggesting that Btk is upstream of pp60(src). We propose a role for Btk in the early steps of activation of SMCE in human platelets.


Assuntos
Plaquetas/enzimologia , Cálcio/metabolismo , Proteínas Tirosina Quinases/química , Actinas/metabolismo , Tirosina Quinase da Agamaglobulinemia , Plaquetas/metabolismo , Western Blotting , Sobrevivência Celular , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Ativação Enzimática , Humanos , Peróxido de Hidrogênio/farmacologia , Imunoprecipitação , Ionomicina/farmacologia , Fosforilação , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Tapsigargina/metabolismo , Trombina/metabolismo , Fatores de Tempo
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