Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Sci Rep ; 14(1): 3838, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360830

RESUMO

Though new targeted therapies for colorectal cancer, which progresses from local intestinal tumors to metastatic disease, are being developed, tumor specificity remains an important problem, and side effects a major concern. Here, we show that the protein-fatty acid complex BAMLET (bovine alpha-lactalbumin made lethal to tumor cells) can act as a peroral treatment for colorectal cancer. ApcMin/+ mice, which carry mutations relevant to hereditary and sporadic human colorectal cancer, that received BAMLET in the drinking water showed long-term protection against tumor development and decreased expression of tumor growth-, migration-, metastasis- and angiogenesis-related genes. BAMLET treatment via drinking water inhibited the Wnt/ß-catenin and PD-1 signaling pathways and prolonged survival without evidence of toxicity. Systemic disease in the lungs, livers, spleens, and kidneys, which accompanied tumor progression, was inhibited by BAMLET treatment. The metabolic response to BAMLET included carbohydrate and lipid metabolism, which were inhibited in tumor prone ApcMin/+ mice and weakly regulated in C57BL/6 mice, suggesting potential health benefits of peroral BAMLET administration in addition to the potent antitumor effects. Together, these findings suggest that BAMLET administration in the drinking water maintains antitumor pressure by removing emergent cancer cells and reprogramming gene expression in intestinal and extra-intestinal tissues.


Assuntos
Neoplasias Colorretais , Água Potável , Camundongos , Humanos , Animais , Bovinos , Camundongos Endogâmicos C57BL , Transdução de Sinais , beta Catenina
2.
Int J Cancer ; 153(3): 584-599, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-36891980

RESUMO

Bladder cancer is common and one of the most costly cancer forms, due to a lack of curative therapies. Recently, clinical safety and efficacy of the alpha1-oleate complex was demonstrated in a placebo-controlled study of nonmuscle invasive bladder cancer. Our study investigated if long-term therapeutic efficacy is improved by repeated treatment cycles and by combining alpha1-oleate with low-dose chemotherapy. Rapidly growing bladder tumors were treated by intravesical instillation of alpha1-oleate, Epirubicin or Mitomycin C alone or in combination. One treatment cycle arrested tumor growth, with a protective effect lasting at least 4 weeks in mice receiving 8.5 mM of alpha1-oleate alone or 1.7 mM of alpha-oleate combined with Epirubicin or Mitomycin C. Repeated treatment cycles extended protection, defined by a lack of bladder pathology and a virtual absence of bladder cancer-specific gene expression. Synergy with Epirubicin was detected at the lower alpha1-oleate concentration and in vitro, alpha1-oleate was shown to enhance the uptake and nuclear translocation of Epirubicin, by tumor cells. Effects at the chromatin level affecting cell proliferation were further suggested by reduced BrdU incorporation. In addition, alpha1-oleate triggered DNA fragmentation, defined by the TUNEL assay. The results suggest that bladder cancer development may be prevented long-term in the murine model, by alpha1-oleate alone or in combination with low-dose Epirubicin. In addition, the combination of alpha1-oleate and Epirubicin reduced the size of established tumors. Exploring these potent preventive and therapeutic effects will be of immediate interest in patients with bladder cancer.


Assuntos
Neoplasias da Bexiga Urinária , Bexiga Urinária , Animais , Camundongos , Antibióticos Antineoplásicos , Epirubicina , Mitomicina/uso terapêutico , Recidiva Local de Neoplasia/patologia , Ácido Oleico , Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/prevenção & controle , Neoplasias da Bexiga Urinária/patologia
3.
Biofactors ; 48(5): 1145-1159, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35388547

RESUMO

Complexes formed by the alpha1 N-terminal peptide of alpha-lactalbumin and oleic acid (alpha1-oleate) interact with lipid bilayers. Plasma membrane perturbations trigger tumor cell death but normal differentiated cells are more resistant, and their plasma membranes are less strongly affected. This study examined membrane lipid composition as a determinant of tumor cell reactivity. Bladder cancer tissue showed a higher abundance of unsaturated lipids enriched in phosphatidylcholine, PC (36:4) and PC (38:4), and sphingomyelin, SM (36:1) than healthy bladder tissue, where saturated lipids predominated and the lipid extracts from bladder cancer tissue inhibited the tumoricidal effect of the complex more effectively than healthy tissue extracts. Furthermore, unsaturated PC in solution inhibited tumor cell death, and the complex interacted with giant unilamellar vesicles formed by PC, confirming the affinity of alpha1-oleate for fluid membranes enriched in PC. Quartz Crystal Microbalance with dissipation monitoring (QCM-D) detected a preference of the complex for the liquid-disordered phase, suggesting that the insertion into PC-based membranes and the resulting membrane perturbations are influenced by membrane lipid saturation. The results suggest that the membrane lipid composition is functionally important and that specific unsaturated membrane lipids may serve as "recognition motifs" for broad-spectrum tumoricidal molecules such as alpha1-oleate.


Assuntos
Bicamadas Lipídicas , Neoplasias da Bexiga Urinária , Humanos , Lactalbumina/química , Lactalbumina/metabolismo , Lactalbumina/farmacologia , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Lipídeos de Membrana/química , Lipídeos de Membrana/metabolismo , Ácido Oleico/química , Ácido Oleico/metabolismo , Ácido Oleico/farmacologia , Fosfatidilcolinas/química , Esfingomielinas/química , Extratos de Tecidos , Lipossomas Unilamelares
4.
Nat Commun ; 12(1): 3427, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103518

RESUMO

Partially unfolded alpha-lactalbumin forms the oleic acid complex HAMLET, with potent tumoricidal activity. Here we define a peptide-based molecular approach for targeting and killing tumor cells, and evidence of its clinical potential (ClinicalTrials.gov NCT03560479). A 39-residue alpha-helical peptide from alpha-lactalbumin is shown to gain lethality for tumor cells by forming oleic acid complexes (alpha1-oleate). Nuclear magnetic resonance measurements and computational simulations reveal a lipid core surrounded by conformationally fluid, alpha-helical peptide motifs. In a single center, placebo controlled, double blinded Phase I/II interventional clinical trial of non-muscle invasive bladder cancer, all primary end points of safety and efficacy of alpha1-oleate treatment are reached, as evaluated in an interim analysis. Intra-vesical instillations of alpha1-oleate triggers massive shedding of tumor cells and the tumor size is reduced but no drug-related side effects are detected (primary endpoints). Shed cells contain alpha1-oleate, treated tumors show evidence of apoptosis and the expression of cancer-related genes is inhibited (secondary endpoints). The results are especially encouraging for bladder cancer, where therapeutic failures and high recurrence rates create a great, unmet medical need.


Assuntos
Peptídeos/química , Peptídeos/uso terapêutico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Sequência de Aminoácidos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Endocitose/efeitos dos fármacos , Determinação de Ponto Final , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Ácidos Oleicos/química , Peptídeos/farmacologia , Placebos , Conformação Proteica , Espectroscopia de Prótons por Ressonância Magnética , Termodinâmica , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia
5.
J Clin Invest ; 131(4)2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33320835

RESUMO

Unlike pathogens, which attack the host, commensal bacteria create a state of friendly coexistence. Here, we identified a mechanism of bacterial adaptation to the host niche, where they reside. Asymptomatic carrier strains were shown to inhibit RNA polymerase II (Pol II) in host cells by targeting Ser2 phosphorylation, a step required for productive mRNA elongation. Assisted by a rare, spontaneous loss-of-function mutant from a human carrier, the bacterial NlpD protein was identified as a Pol II inhibitor. After internalization by host cells, NlpD was shown to target constituents of the Pol II phosphorylation complex (RPB1 and PAF1C), attenuating host gene expression. Therapeutic efficacy of a recombinant NlpD protein was demonstrated in a urinary tract infection model, by reduced tissue pathology, accelerated bacterial clearance, and attenuated Pol II-dependent gene expression. The findings suggest an intriguing, evolutionarily conserved mechanism for bacterial modulation of host gene expression, with a remarkable therapeutic potential.


Assuntos
Infecções por Escherichia coli , Proteínas de Escherichia coli , Escherichia coli , Regulação Bacteriana da Expressão Gênica/imunologia , Lipoproteínas , RNA Polimerase II , Infecções Urinárias , Animais , Linhagem Celular Tumoral , Escherichia coli/genética , Escherichia coli/imunologia , Infecções por Escherichia coli/genética , Infecções por Escherichia coli/imunologia , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/imunologia , Feminino , Humanos , Lipoproteínas/genética , Lipoproteínas/imunologia , Camundongos , RNA Polimerase II/genética , RNA Polimerase II/imunologia , Infecções Urinárias/genética , Infecções Urinárias/imunologia
6.
Horm Mol Biol Clin Investig ; 41(2)2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31967960

RESUMO

Background Inflammation is one of the most important responses of the body against infection or disease, and it protects tissues from injury; however, it causes redness, swelling, pain, fever and loss of function. The aim of this present study was to evaluate the anti-inflammatory activity of emu oil (Eu) formulated nanofibrous scaffold in HFFF2 fibroblast cells. Materials and methods Eu was formulated successfully in nanofibers through the electrospinning method. Besides, the morphological and structural properties of Eu nanofibres were evaluated using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The MTT assay (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) was performed to evaluate the HFFF2 fibroblast cells' viability. Also, real-time polymerase chain reaction (PCR) was used to evaluate the anti-inflammatory signaling pathway in treated HFFF2 cells with Eu nanofiber. Results Our study showed that the Eu nanofiber increased the viability of fibroblast HFFF2 cells (p < 0.05). Also, the expression of interleukin1 (IL1), IL6 and tumor necrosis factor- alpha (TNF-α) pro-inflammatory cytokines genes were significantly decreased in treated HFFF2 cells with Eu nanofiber (p < 0.05). Conclusions In conclusion, Eu nanofiber scaffold potentially can reduce the inflammation process through downregulation of IL-1, IL-6 and TNF-α cytokines.


Assuntos
Anti-Inflamatórios/farmacologia , Interleucina-1/biossíntese , Interleucina-6/biossíntese , Nanofibras/química , Óleos/farmacologia , Alicerces Teciduais , Fator de Necrose Tumoral alfa/biossíntese , Animais , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Implantes de Medicamento , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Inflamação , Interleucina-1/genética , Interleucina-6/genética , Microscopia Eletrônica de Varredura , Óleos/administração & dosagem , Poliésteres , Polietilenoglicóis , Reação em Cadeia da Polimerase em Tempo Real , Espectroscopia de Infravermelho com Transformada de Fourier , Fator de Necrose Tumoral alfa/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA