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1.
Int J Mol Sci ; 23(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36555718

RESUMO

Triple negative breast cancer (TNBC) is the most aggressive subtype of breast cancer in women. It has the poorest prognosis along with limited therapeutic options. Smart nano-based carriers are emerging as promising approaches in treating TNBC due to their favourable characteristics such as specifically delivering different cargos to cancer cells. However, nanoparticles' tumour cell uptake, and subsequent drug release, are essential factors considered during the drug development process. Contemporary qualitative analyses based on imaging are cumbersome and prone to human biases. Deep learning-based algorithms have been well-established in various healthcare settings with promising scope in drug discovery and development. In this study, the performance of five different convolutional neural network models was evaluated. In this research, we investigated two sequential models from scratch and three pre-trained models, VGG16, ResNet50, and Inception V3. These models were trained using confocal images of nanoparticle-treated cells loaded with a fluorescent anticancer agent. Comparative and cross-validation analyses were further conducted across all models to obtain more meaningful results. Our models showed high accuracy in predicting either high or low drug uptake and release into TNBC cells, indicating great translational potential into practice to aid in determining cellular uptake at the early stages of drug development in any area of research.


Assuntos
Antineoplásicos , Aprendizado Profundo , Nanopartículas , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Neoplasias de Mama Triplo Negativas/patologia , Inteligência Artificial , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
2.
Cells ; 11(3)2022 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-35159207

RESUMO

Bone is one of the most common metastatic sites among breast cancer (BC) patients. Once bone metastasis is developed, patients' survival and quality of life will be significantly declined. At present, there are limited therapeutic options for BC patients with bone metastasis. Different nanotechnology-based delivery systems have been developed aiming to specifically deliver the therapeutic agents to the bone. The conjugation of targeting agents to nanoparticles can enhance the selective delivery of various payloads to the metastatic bone lesion. The current review highlights promising and emerging advanced nanotechnologies designed for targeted delivery of anticancer therapeutics, contrast agents, photodynamic and photothermal materials to the bone to achieve the goal of treatment, diagnosis, and prevention of BC bone metastasis. A better understanding of various properties of these new therapeutic approaches may open up new landscapes in medicine towards improving the quality of life and overall survival of BC patients who experience bone metastasis.


Assuntos
Neoplasias Ósseas , Neoplasias da Mama , Nanopartículas , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/secundário , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Nanopartículas/uso terapêutico , Qualidade de Vida
3.
Drug Deliv Transl Res ; 12(5): 1017-1028, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-33970463

RESUMO

Breast cancer remains the most commonly diagnosed cancer and the leading cause of cancer-related death among women worldwide. With the projected increase in breast cancer cases in recent years, optimising treatment becomes increasingly important. Current treatment modalities in breast cancer present major limitations, including chemoresistance, dose-limiting adverse effects and lack of selectivity in aggressive subtypes of breast cancers such as triple-negative breast cancer. Nanodiamonds have demonstrated promising outcomes in preclinical models from their unique surface characteristics allowing optimised delivery of various therapeutic agents, overcoming some of the significant hurdles in conventional treatment modalities. This review will present an update on preclinical findings of nanodiamond-based drug delivery systems for breast cancer therapy to date, challenges with the use of nanodiamonds along with considerations for future research.


Assuntos
Nanodiamantes , Neoplasias de Mama Triplo Negativas , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Nanodiamantes/uso terapêutico
4.
Pharmaceutics ; 15(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36678741

RESUMO

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer with a high risk of metastasis and therapeutic resistance. These issues are closely linked to the tumour microenvironment (TME) surrounding the tumour tissue. The association between residing TME components with tumour progression, survival, and metastasis has been well elucidated. Focusing on cancer cells alone is no longer considered a viable approach to therapy; thus, there is a high demand for TME targeting. The benefit of using nanoparticles is their preferential tumour accumulation and their ability to target TME components. Several nano-based platforms have been investigated to mitigate microenvironment-induced angiogenesis, therapeutic resistance, and tumour progression. These have been achieved by targeting mesenchymal originating cells (e.g., cancer-associated fibroblasts, adipocytes, and stem cells), haematological cells (e.g., tumour-associated macrophages, dendritic cells, and myeloid-derived suppressor cells), and the extracellular matrix within the TME that displays functional and architectural support. This review highlights the importance of nanotechnology-based therapeutics as a promising approach to target the TME and improve treatment outcomes for TNBC patients, which can lead to enhanced survival and quality of life. The role of different nanotherapeutics has been explored in the established TME cell-driven populations.

5.
Biomedicines ; 9(12)2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34944738

RESUMO

Breast cancer is the most diagnosed cancer and is the leading cause of cancer mortality in women. Triple-negative breast cancer (TNBC) is an aggressive form of breast cancer. Often, TNBC is not effectively treated due to the lack of specificity of conventional therapies and results in relapse and metastasis. Breast cancer-associated fibroblasts (BCAFs) are the predominant cells that reside in the tumor microenvironment (TME) and regulate tumorigenesis, progression and metastasis, and therapy resistance. BCAFs secrete a wide range of factors, including growth factors, chemokines, and cytokines, some of which have been proved to lead to a poor prognosis and clinical outcomes. This TME component has been emerging as a promising target due to its crucial role in cancer progression and chemotherapy resistance. A number of therapeutic candidates are designed to effectively target BCAFs with a focus on their tumor-promoting properties and tumor immune response. This review explores various agents targeting BCAFs in TNBC, including small molecules, nucleic acid-based agents, antibodies, proteins, and finally, nanoparticles.

6.
Endocr Relat Cancer ; 28(11): R251-R269, 2021 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-34236041

RESUMO

Cancer is the uncontrolled division of abnormal cells in a specific organ. Globally, about one in six deaths is due to cancer. Despite the plethora of research being undertaken worldwide to find a cure for cancer, it remains a significant challenge. Cancer targeting via agents designed to interfere with some specifically or highly expressed molecules in cancer cells has been a shift in the treatment of various forms of cancers. The development of drug delivery systems, specifically to cancer cells, is a common approach that succeeded in increasing the efficacy and reducing the side effects of different anticancer agents. Gonadotropin-releasing hormone (GnRH) is a naturally occurring hormone with receptors overexpressed in many types of cancers related or unrelated to the reproductive system. Several drug delivery systems were developed using GnRH derivatives as targeting agents. In this review, we first discuss the role of GnRH and its receptors in cancer. Then, we provide a detailed insight into different delivery systems developed using GnRH derivatives as targeting agents in various types of GnRH receptor overexpressing cancers. Some promising findings from these studies indicate that GnRH receptor targeting is a potential strategy to efficiently guide anticancer therapeutics, diagnostic agents, and nucleic acids directly to cancer cells. Lastly, some limitations of the current research and suggestions for more successful outcomes in clinical trials of these delivery systems are highlighted.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Sistemas de Liberação de Medicamentos , Hormônio Liberador de Gonadotropina , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Receptores LHRH
7.
Scientometrics ; 126(8): 7005-7050, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34188334

RESUMO

Following the outbreak of SARS-CoV-2 disease, within less than 8 months, the 50 years-old scholarly literature of coronaviruses grew to nearly three times larger than its size prior to 2020. Here, temporal evolution of the coronavirus literature over the last 30 years (N = 43,769) is analysed along with its subdomain of SARS-CoV-2 articles (N = 27,460) and the subdomain of reviews and meta-analytic studies (N = 1027). The analyses are conducted through the lenses of co-citation and bibliographic coupling of documents. (1) Of the N = 1204 review and meta-analytical articles of the coronavirus literature, nearly 88% have been published and indexed during the first 8 months of 2020, marking an unprecedented attention to reviews and meta-analyses in this domain, prompted by the SARS-CoV-2 pandemic. (2) The subset of 2020 SARS-CoV-2 articles is bibliographically distant from the rest of this literature published prior to 2020. Individual articles of the SARS-CoV-2 segment with a bridging role between the two bodies of articles (i.e., before and after 2020) are identifiable. (3) Furthermore, the degree of bibliographic coupling within the 2020 SARS-CoV-2 cluster is much poorer compared to the cluster of articles published prior to 2020. This could, in part, be explained by the higher diversity of topics that are studied in relation to SARS-CoV-2 compared to the literature of coronaviruses published prior to the SARS-CoV-2 disease. (4) The analyses on the subset of SARS-CoV-2 literature identified studies published prior to 2020 that have now proven highly instrumental in the development of various clusters of publications linked to SARS-CoV-2. In particular, the so-called "sleeping beauties" of the coronavirus literature with an awakening in 2020 were identified, i.e., previously published studies of this literature that had remained relatively unnoticed for several years but gained sudden traction in 2020 in the wake of the SARS-CoV-2 outbreak. This work documents the historical development of the literature on coronaviruses as an event-driven literature and as a domain that exhibited, arguably, the most exceptional case of publication burst in the history of science. It also demonstrates how scholarly efforts undertaken during peace time or prior to a disease outbreak could suddenly play a critical role in prevention and mitigation of health disasters caused by new diseases. Supplementary Information: The online version contains supplementary material available at 10.1007/s11192-021-04036-4.

8.
Future Oncol ; 17(6): 711-722, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33136464

RESUMO

In recent years, cancer immunotherapy has evolved as an exciting novel strategy for researchers and clinicians worldwide. Immunotherapeutic agents such as immune checkpoint blockers have changed the standard-of-care treatment provided for many tumors. Unfortunately, only a small proportion of patients respond effectively to these checkpoint inhibitors. Moreover, the immunosuppressive pathways for cancer are probably too complicated to achieve optimal outcome with immune checkpoint inhibitors alone. Combining current therapeutic options and immunotherapy-based approaches is being explored as an effective strategy to treat cancer. The use of nanotechnology-based platforms for delivery of immunotherapeutic agents or combination therapy could offer a major advantage over conventional anticancer treatment options. This review highlights the potential role of different nanotechnology-based strategies in improving the efficacy of immune checkpoint blockade therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Inibidores de Checkpoint Imunológico/administração & dosagem , Neoplasias/tratamento farmacológico , Nanomedicina Teranóstica/métodos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Lipossomos , Imagem Molecular/métodos , Sondas Moleculares/administração & dosagem , Nanopartículas/administração & dosagem , Neoplasias/diagnóstico por imagem , Neoplasias/imunologia , Nanomedicina Teranóstica/tendências , Resultado do Tratamento
9.
Pharm Dev Technol ; 25(9): 1118-1126, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32686553

RESUMO

Metastatic (secondary) bone cancer is one of the major causes of death in patients with advanced cancer. A lack of options for the targeted delivery of a desired therapeutic payload to multiple tumour modules located in the bone is still one of the foremost hurdles in the treatment/prevention of metastatic bone cancer. Curcumin has a proven anticancer potential with known challenges for application as a pharmaceutical agent. We have previously shown that micellar formulations could overcome some of these challenges and enhances its anti-cancer activity. In this study, we have developed a targeted drug delivery system using bisphosphonate (alendronate) conjugated Pluronic F127 micelles that could efficiently target, and specifically deliver curcumin to the osteolytic tumour microenvironment in the bone. Characterization of the formulation of curcumin-encapsulated alendronate-conjugated micelles demonstrated that the micelles have nanoscale size (∼27 nm) with a positive surface charge (+2.87 mV) and 4% drug loading. The alendronate-conjugated micelles showed significant bone-targeting potential. Rapid binding of the micelles to hydroxyapatite surface suggested that these nanoparticles are promising carriers for effective and targeted delivery of curcumin to osteolytic tumours in the bone.


Assuntos
Antineoplásicos/química , Neoplasias Ósseas/tratamento farmacológico , Curcumina/química , Difosfonatos/química , Alendronato/administração & dosagem , Alendronato/química , Antineoplásicos/administração & dosagem , Curcumina/administração & dosagem , Difosfonatos/administração & dosagem , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos/efeitos dos fármacos , Durapatita/química , Micelas , Nanopartículas/química , Tamanho da Partícula , Poloxâmero/química , Polímeros/química , Microambiente Tumoral/efeitos dos fármacos
10.
ACS Biomater Sci Eng ; 5(10): 5189-5208, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33455225

RESUMO

A nanotheranostic system was developed using α-lactalbumin along with Fe3O4 nanoparticles as an magnetic resonance imaging (MRI) contrast agent for medical imaging and doxorubicin as the therapeutic agent. α-lactalbumin was precipitated and cross-linked using poly(ethylene glycol) and glutaraldehyde. Besides, polyethylenimine was applied to increase the number of amine groups during cross-linking between α-lactalbumin and Fe3O4 nanoparticles. Interestingly, 90% of the initial protein used for the coaggregation process was incorporated in the prepared 130 nm nanocomposites, which facilitated the 85% doxorubicin loading. Formation of pH-sensitive imine bonds between glutaraldehyde and amine groups on α-lactalbumin and polyethylenimine resulted in higher release of doxorubicin at acidic pHs and consequently development of a pH-sensitive nanocarrier. The designed nanocomposite was less immunogenic owing to stimulating the production of less amounts of C3a, C5a, platelet factor 4, glycoprotein IIb/IIIa, platelet-derived ß-thromboglobulin, interleukin-6, and interleukin-1ß compared to the free doxorubicin. Furthermore, 1000 µg/mL nanocomposite led to 0.2% hemolytic activity, much less than the 5% standard limit. The void nanocarrier induced no significant level of cytotoxicity in breast cancer and normal cells following 96 h incubation. The doxorubicin-loaded nanocomposite presented higher cytotoxicity, apoptosis induction, and doxorubicin uptake in cancer cells than free doxorubicin. Conversely, lower cytotoxicity, apoptosis induction, and doxorubicin uptake were observed in normal cells treated with the doxorubicin-loaded nanocarrier compared to free doxorubicin. In line with the results of in vitro experiments, in vivo studies on tumor-bearing mice showed more suppression of tumor growth by the doxorubicin-loaded nanocomposite compared to the free drug. Moreover, the pharmacokinetic study revealed slow release of doxorubicin from the nanocomposite. Besides, in vitro and in vivo MRI studies presented a higher r2/r1 ratio and comparable contrast to the commercially available DOTAREM, respectively. Our findings suggest that this new nanocomposite is a promising nanotheranostic system with promising potential for cancer therapy and diagnosis.

11.
Curr Pharm Des ; 24(28): 3320-3331, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29921200

RESUMO

BACKGROUND: Breast cancer is the most frequently diagnosed malignancy in women worldwide. Breast cancer tends to metastasize to bone. Around 70% of the breast cancer patients eventually develop bone metastasis. After the bone invasion, metastatic cells disrupt the balance between osteoblastic and osteoclastic activities, leading to skeletal complications, characterized by pain and pathological fractures and hence worsening the patient's quality of life. Once tumor invades the bone, it is hard to treat it with, the so-far available treatments options (e.g. bisphosphonates and denosumab). Bone metastasis should be essentially controlled, in cancer treatment and there is a strong need to explore new, more efficient therapeutic targets. This review discusses the bone physiological processes and the recent advances in exploring different pathways involved in bone metastasis. Furthermore, some novel treatment options, which are under preclinical and clinical investigations, are highlighted. CONCLUSION: A deeper understanding of these metastatic pathways can provide oncology researchers with novel avenues for treating bone metastasis, one of the main challenges to cure breast cancer. The restoration of healthy bone environment will not only improve the patient's quality of life but also reduces the tumor burden.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Animais , Neoplasias Ósseas/secundário , Feminino , Humanos
12.
J Med Chem ; 60(20): 8309-8320, 2017 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-28958147

RESUMO

Gonadotropin-releasing hormone (GnRH) agonists (e.g., triptorelin) are used for androgen suppression therapy. They possess improved stability as compared to the natural GnRH, yet they suffer from a poor pharmacokinetic profile. To address this, we used a GnRH peptide-modified dendrimer platform with and without lipidation strategy. Dendrimers were synthesized on a polylysine core and bore either native GnRH (1, 2, and 5) or lipid-modified GnRH (3 and 4). Compound 3, which bore a lipidic moiety in a branched tetramer structure, showed approximately 10-fold higher permeability and metabolic stability and 39 times higher antitumor activity against hormone-resistant prostate cancer cells (DU145) relative to triptorelin. In gonadotropin-release experiments, dendrimer 3 was shown to be the most potent construct. Dendrimer 3 showed similar luteinizing hormone (LH)-release activity to triptorelin in mice. Our findings indicate that dendrimer 3 is a promising analog with higher potency for the treatment of hormone-resistant prostate cancer than the currently available GnRH agonists.


Assuntos
Proliferação de Células/efeitos dos fármacos , Dendrímeros/farmacologia , Hormônio Liberador de Gonadotropina/agonistas , Gonadotropinas/metabolismo , Animais , Células CACO-2 , Permeabilidade da Membrana Celular/efeitos dos fármacos , Dendrímeros/química , Dendrímeros/farmacocinética , Hormônio Foliculoestimulante/metabolismo , Humanos , Hormônio Luteinizante/metabolismo , Camundongos , Pamoato de Triptorrelina/farmacologia
14.
Expert Opin Drug Deliv ; 13(4): 507-22, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26787260

RESUMO

INTRODUCTION: Oral delivery of therapeutic peptide hormones offers the promise of greater patient compliance when compared to parenteral administration routes. However, it is a huge challenge in the pharmaceutical field. Due to increasing demand for oral delivery of peptide hormones such as insulin, gonadotropin-releasing hormones, and calcitonin, various technologies have been explored to overcome the associated hurdles. AREAS COVERED: This review article summarizes the physiological barriers to the oral delivery of peptide hormones and some of the key strategies to circumvent these barriers and enhance peptide hormones' oral bioavailability. In addition, recent advances in oral formulation strategies of peptide hormones, under development and within the clinical trial stages, are discussed. EXPERT OPINION: The pharmaceutical industry has devoted much effort to develop new, and often complex peptide hormone products based on formulation strategy. Use of the native structure of the peptide hormones in oral formulations could result in an unpredictable pharmacokinetic profile. Authors believe that considering chemical modification prior to formulation is essential to achieve orally active products. Although no major breakthrough has been achieved for effective oral delivery of peptides hormones yet, the substantial efforts by industrial and academic laboratories might yield successful results in near future.


Assuntos
Química Farmacêutica/métodos , Sistemas de Liberação de Medicamentos/métodos , Hormônios Peptídicos/administração & dosagem , Administração Oral , Disponibilidade Biológica , Calcitonina/administração & dosagem , Hormônio Liberador de Gonadotropina/administração & dosagem , Humanos , Insulina/administração & dosagem
15.
Pharm Dev Technol ; 21(6): 664-71, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25946073

RESUMO

This study aimed at evaluating whether derivatization of luteinizing hormone-releasing hormone (LHRH) peptide with an amphiphilic lipoamino acid moiety could allow, along with other technological and/or pharmacokinetic advantages, to improve its encapsulation in liposomes, potentially driving its further body distribution and cellular uptake. Experimental data confirmed that a lipophilic derivative of LHRH was efficiently incorporated in various liposomal systems, differing in lipid composition and surface charge, and obtained using different methods of production. Incubation of liposomes, loaded with a fluorescent derivative of the LHRH prodrug, with NCTC keratinocytes or Caco-2 cell cultures showed that the carriers can be rapidly internalized. Conversely, the internalization of the free prodrug occurred only at very high concentrations.


Assuntos
Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Liberador de Gonadotropina/metabolismo , Pró-Fármacos/administração & dosagem , Pró-Fármacos/metabolismo , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Composição de Medicamentos , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Lipossomos
16.
Chem Sci ; 7(4): 2492-2500, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-28660018

RESUMO

Glycosylation of peptides is a promising strategy for modulating the physicochemical properties of peptide drugs and for improving their absorption through biological membranes. This review highlights various methods for the synthesis of glycoconjugates and recent progress in the development of glycosylated peptide therapeutics. Furthermore, the impacts of glycosylation in overcoming the existing barriers that restrict oral and brain delivery of peptides are described herein.

17.
Int J Pharm ; 495(1): 106-111, 2015 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-26325323

RESUMO

In the current study, the efficacy and pharmacokinetic profile of lactose-conjugated luteinizing hormone releasing hormone (LHRH) was examined following oral administration in male rats. A rapid and sensitive liquid chromatography/mass spectrometry technique was developed and applied for measuring the concentration of lactose[Q(1)][w(6)]LHRH (compound 1) in rat plasma in order to allow measurement of pharmacokinetic parameters. LH release was evaluated using a sandwich ELISA. Maximum serum concentration (Cmax = 0.11 µg/ml) was reached at 2h (Tmax) following oral administration of the compound at 10mg/kg. The half-life was determined to be 2.6h. The absolute bioavailability of the orally administered compound was found to be 14%, which was a remarkable improvement compared to zero-to-low oral bioavailability of the native peptide. Compound 1 was effective in stimulating LH release at 20mg/kg after oral administration. The method was validated at a linear range of 0.01-20.0 µg/ml and a correlation coefficient of r(2) ≥ 0.999. The accuracy and precision values showed the reliability and reproducibility of the method for evaluation of the pharmacokinetic parameters. These findings showed that the lactose derivative of LHRH has a therapeutic potential to be further developed as an orally active therapeutics for the treatment of hormone-dependent diseases.


Assuntos
Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/farmacologia , Lactose/química , Administração Oral , Animais , Disponibilidade Biológica , Hormônio Liberador de Gonadotropina/química , Hormônio Liberador de Gonadotropina/farmacocinética , Meia-Vida , Lactose/administração & dosagem , Lactose/sangue , Hormônio Luteinizante/sangue , Masculino , Ratos
18.
AAPS J ; 17(5): 1135-43, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25956382

RESUMO

The enzymatic stability, antitumor activity, and gonadotropin stimulatory effects of glycosylated luteinizing hormone-releasing hormone (LHRH) analogs were investigated in this study. Conjugation of carbohydrate units, including lactose (Lac), glucose (GS), and galactose (Gal) to LHRH peptide protected the peptide from proteolytic degradation and increased the peptides' half-lives in human plasma, rat kidney membrane enzymes, and liver homogenate markedly. Among all seven modified analogs, compound 1 (Lac-[Q(1)][w(6)]LHRH) and compound 6 (GS(4)-[w(6)]LHRH) were stable in human plasma during 4 h of experiment. The half-lives of compounds 1 and 6 improved significantly in kidney membrane enzymes (from 3 min for LHRH to 68 and 103 min, respectively). The major cleavage sites for most of the glycosylated compounds were found to be at Trp(3)-Ser(4) and Ser(4)-Tyr(5) in compounds 1-5. Compound 6 was hydrolyzed at Ser(4)-Tyr(5) and the sugar conjugation site. The antiproliferative activity of the glycopeptides was evaluated on LHRH receptor-positive prostate cancer cells. The glycosylated LHRH derivatives had a significant growth inhibitory effect on the LNCaP cells after a 48-h treatment. It was demonstrated that compound 1 significantly increased the release of luteinizing hormone (LH) at 5 and 10 nM concentrations and compound 5 (GS-[Q(1)]LHRH) stimulated the release of follicle-stimulating hormone (FSH) at 5 nM concentration in dispersed rat pituitary cells (p < 0.05). In our studies, compound 1-bearing lactose and D-Trp was the most stable and active and is a promising candidate for future preclinical investigations in terms of in vitro biological activity and metabolic stability.


Assuntos
Hormônio Foliculoestimulante/metabolismo , Hormônio Liberador de Gonadotropina/farmacologia , Fígado/metabolismo , Hormônio Luteinizante/metabolismo , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Glicosilação , Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/farmacocinética , Meia-Vida , Humanos , Masculino , Hipófise/citologia , Hipófise/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
19.
ChemMedChem ; 10(5): 901-10, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25809441

RESUMO

The immunoneutralization of gonadotropin-releasing hormone (GnRH) can be used for the treatment of human hormone-dependent male and female cancers or as immunocontraceptives in animals. Vaccine candidates 1 [Th(K-LP)GnRH], 2 [GnRH(K-LP)Th], 3 [GnRH(K-Th)LP], and 4 [Th(K-GnRH)LP] (for which K=lysine, LP=lipopeptide Ser-Ser-C16 -C16 , and Th=T helper cell epitope influenza HA2), were synthesized by assembling a CD4(+) T helper cell epitope (Th), GnRH, and an adjuvanting lipid moiety (LP) in various spatial arrangements. All compounds were efficiently taken up by antigen-presenting cells with significant immunogenicity without an external adjuvant. Compounds 2, 3, and 4, in which GnRH is conjugated through its C terminus, produced higher GnRH-specific antibody responses than construct 1, in which the GnRH moiety is conjugated through its N terminus. All four constructs induced a significant antiproliferative effect (up to 55 %) on GnRH-receptor-positive LNCaP cells, but showed weaker activity in the GnRH-receptor-negative SKOV-3 cell line. Marked degenerative changes were observed in morphology and follicular development in the ovaries of immunized mice, with approximately 30 % higher degenerative antral and atretic follicles.


Assuntos
Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Hormônio Liberador de Gonadotropina/imunologia , Vacinas Sintéticas/química , Vacinas Sintéticas/imunologia , Animais , Células Dendríticas/imunologia , Feminino , Humanos , Injeções Intramusculares , Macrófagos/imunologia , Camundongos Endogâmicos BALB C , Estrutura Molecular , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Vacinas Sintéticas/administração & dosagem
20.
Vaccine ; 33(12): 1453-8, 2015 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-25678242

RESUMO

Immunocastration using gonadotropin-releasing hormone (GnRH)-based vaccines has been investigated in rams to reduce aggressive and sexual behaviour and to control meat quality. Despite considerable efforts, a practical GnRH vaccine has yet to be developed for rams. In the present study, a A GnRH-lipopeptide vaccine (GnRH-LP) including two copies of GnRH, 2-amino-d,l-hexadecanoic acid (C16), and a unique T helper epitope, was examined in rams. Rams received a primary and secondary vaccination of GnRH-LP without additional adjuvant (Group 1) or with the adjuvant AdjuVac™ (Group 2). In both Group 1 and 2 anti-GnRH antibody titres increased after secondary vaccination, however, the antibody titres were higher (p<0.01) for rams in Group 2. The latter rams showed a marked decrease in testicular size. The marked and sustained reduction in testicular size in rams treated with GnRH-LP+AdjuVac™ provides the basis for an effective immunocastration vaccine in rams.


Assuntos
Anticorpos/imunologia , Hormônio Liberador de Gonadotropina/imunologia , Carneiro Doméstico/imunologia , Testículo/anatomia & histologia , Vacinas de Subunidades Antigênicas/imunologia , Adjuvantes Imunológicos , Animais , Epitopos de Linfócito T , Hormônio Liberador de Gonadotropina/genética , Masculino , Vacinas de DNA/imunologia
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