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1.
Cancer Med ; 13(7): e7091, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38553868

RESUMEN

BACKGROUND: The molecular content of urine is defined by filtration in the kidneys and by local release from tissues lining the urinary tract. Pathological processes and different therapies change the molecular composition of urine and a variety of markers have been analyzed in patients with bladder cancer. The response to BCG immunotherapy and chemotherapy has been extensively studied and elevated urine concentrations of IL-1RA, IFN-α, IFN-γ TNF-α, and IL-17 have been associated with improved outcome. METHODS: In this study, the host response to intravesical alpha 1-oleate treatment was characterized in patients with non-muscle invasive bladder cancer by proteomic and transcriptomic analysis. RESULTS: Proteomic profiling detected a significant increase in multiple cytokines in the treatment group compared to placebo. The innate immune response was strongly activated, including IL-1RA and pro-inflammatory cytokines in the IL-1 family (IL-1α, IL-1ß, IL-33), chemokines (MIP-1α, IL-8), and interferons (IFN-α2, IFN-γ). Adaptive immune mediators included IL-12, Granzyme B, CD40, PD-L1, and IL-17D, suggesting broad effects of alpha 1-oleate treatment on the tumor tissues. CONCLUSIONS: The cytokine response profile in alpha 1-oleate treated patients was similar to that reported in BCG treated patients, suggesting a significant overlap. A reduction in protein levels at the end of treatment coincided with inhibition of cancer-related gene expression in tissue biopsies, consistent with a positive treatment effect. Thus, in addition to killing tumor cells and inducing cell detachment, alpha 1-oleate is shown to activate a broad immune response with a protective potential.


Asunto(s)
Vacuna BCG , Neoplasias de la Vejiga Urinaria , Humanos , Vacuna BCG/uso terapéutico , Proteína Antagonista del Receptor de Interleucina 1/uso terapéutico , Ácido Oléico , Proteómica , Citocinas , Neoplasias de la Vejiga Urinaria/patología , Interferón-alfa/farmacología , Interferón-alfa/uso terapéutico , Inmunidad
2.
Sci Rep ; 14(1): 3838, 2024 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-38360830

RESUMEN

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.


Asunto(s)
Neoplasias Colorrectales , Agua Potable , Ratones , Humanos , Animales , Bovinos , Ratones Endogámicos C57BL , Transducción de Señal , beta Catenina
3.
Int J Cancer ; 153(3): 584-599, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-36891980

RESUMEN

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.


Asunto(s)
Neoplasias de la Vejiga Urinaria , Vejiga Urinaria , Animales , Ratones , Antibióticos Antineoplásicos , Epirrubicina , Mitomicina/uso terapéutico , Recurrencia Local de Neoplasia/patología , Ácido Oléico , Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/prevención & control , Neoplasias de la Vejiga Urinaria/patología
4.
Pathogens ; 13(1)2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-38251349

RESUMEN

Innate immunity is essential for the anti-microbial defense, but excessive immune activation may cause severe disease. In this study, immunotherapy was shown to prevent excessive innate immune activation and restore the anti-bacterial defense. E. coli-infected Asc-/- mice develop severe acute cystitis, defined by IL-1 hyper-activation, high bacterial counts, and extensive tissue pathology. Here, the interleukin-1 receptor antagonist (IL-1RA), which inhibits IL-1 hyper-activation in acute cystitis, was identified as a more potent inhibitor of inflammation and NK1R- and substance P-dependent pain than cefotaxime. Furthermore, IL-1RA treatment inhibited the excessive innate immune activation in the kidneys of infected Irf3-/- mice and restored tissue integrity. Unexpectedly, IL-1RA also accelerated bacterial clearance from infected bladders and kidneys, including antibiotic-resistant E. coli, where cefotaxime treatment was inefficient. The results suggest that by targeting the IL-1 response, control of the innate immune response to infection may be regained, with highly favorable treatment outcomes, including infections caused by antibiotic-resistant strains.

5.
Nat Rev Urol ; 19(7): 419-437, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35732832

RESUMEN

Innovative solutions are needed for the treatment of bacterial infections, and a range of antibacterial molecules have been explored as alternatives to antibiotics. A different approach is to investigate the immune system of the host for new ways of making the antibacterial defence more efficient. However, the immune system has a dual role as protector and cause of disease: in addition to being protective, increasing evidence shows that innate immune responses can become excessive and cause acute symptoms and tissue pathology during infection. This role of innate immunity in disease suggests that the immune system should be targeted therapeutically, to inhibit over-reactivity. The ultimate goal is to develop therapies that selectively attenuate destructive immune response cascades, while augmenting the protective antimicrobial defence but such treatment options have remained underexplored, owing to the molecular proximity of the protective and destructive effects of the immune response. The concept of innate immunomodulation therapy has been developed successfully in urinary tract infections, based on detailed studies of innate immune activation and disease pathogenesis. Effective, disease-specific, immunomodulatory strategies have been developed by targeting specific immune response regulators including key transcription factors. In acute pyelonephritis, targeting interferon regulatory factor 7 using small interfering RNA or treatment with antimicrobial peptide cathelicidin was protective and, in acute cystitis, targeting overactive effector molecules such as IL-1ß, MMP7, COX2, cAMP and the pain-sensing receptor NK1R has been successful in vivo. Furthermore, other UTI treatment strategies, such as inhibiting bacterial adhesion and vaccination, have also shown promise.


Asunto(s)
Cistitis , Pielonefritis , Infecciones Urinarias , Antibacterianos/uso terapéutico , Cistitis/tratamiento farmacológico , Humanos , Inmunomodulación , Pielonefritis/tratamiento farmacológico , Pielonefritis/genética , Pielonefritis/microbiología , Infecciones Urinarias/tratamiento farmacológico
6.
Biofactors ; 48(5): 1145-1159, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35388547

RESUMEN

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.


Asunto(s)
Membrana Dobles de Lípidos , Neoplasias de la Vejiga Urinaria , Humanos , Lactalbúmina/química , Lactalbúmina/metabolismo , Lactalbúmina/farmacología , Membrana Dobles de Lípidos/química , Membrana Dobles de Lípidos/metabolismo , Lípidos de la Membrana/química , Lípidos de la Membrana/metabolismo , Ácido Oléico/química , Ácido Oléico/metabolismo , Ácido Oléico/farmacología , Fosfatidilcolinas/química , Esfingomielinas/química , Extractos de Tejidos , Liposomas Unilamelares
7.
Mol Cell Oncol ; 8(5): 1974278, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34859140

RESUMEN

The protein-lipid complex alpha1-oleate, derived from HAMLET (Human Alpha-lactalbumin Made LEthal to Tumor cells), is identified as a molecular entity with significant therapeutic potential. Structural characterization of the complex and results of a successful placebo-controlled clinical trial are presented.

9.
Eur Urol Open Sci ; 31: 49-58, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34467240

RESUMEN

BACKGROUND: Patients with bladder pain syndrome experience debilitating pain and extreme frequency of urination. Numerous therapeutic approaches have been tested, but as the molecular basis of disease has remained unclear, specific therapies are not available. OBJECTIVE: Recently, a systematic gene deletion strategy identified interleukin-1 (IL-1) hyperactivation as a cause of severe cystitis in a murine model. Treatment with an IL-1 receptor antagonist (IL-1RA) restored health in genetically susceptible mice, linking IL-1-dependent inflammation to pain and pathology in the bladder mucosa. The study objective was to investigate whether IL-1RA treatment might be beneficial in patients with bladder pain syndrome. DESIGN SETTING AND PARTICIPANTS: Patients diagnosed with bladder pain syndrome were invited to participate and subjected to daily IL-1RA injections for 1 wk, followed by a treatment break. Patients with other urological disorders accompanied by pain were included as controls. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: When symptoms returned, treatment was resumed and responding patients were maintained on treatment long term, with individualized dosing regimens. Symptom scores were recorded and molecular effects were quantified by neuropeptide and gene expression analysis. DNA samples were subjected to exome genotyping. RESULTS AND LIMITATIONS: IL-1RA treatment reduced bladder pain and the frequency of urination in 13/17 patients (p < 0.001). Substance P levels in urine were lowered, and responders returned to a more normal lifestyle. Neuroinflammatory-dependent and IL-1-dependent gene networks were inhibited, as well as regulators of innate immunity. Genotyping revealed disease-associated IL1R1, NLRP3, and IL1RN DNA sequence variants in the responders. Controls did not benefit from IL-1RA treatment, except for one patent with cystitis cystica. CONCLUSIONS: In this clinical study, IL-1RA treatment is proposed to reduce chronic bladder pain, immediately and in the long term. Despite the limited number of study patients, the potent acute effect and lasting symptom relief indicate that this therapeutic approach may be worth exploring in controlled clinical trials. PATIENT SUMMARY: Treatment with an interleukin-1 (IL-1) receptor antagonist is proposed for treating bladder pain syndrome, as it can result in symptom relief and increase quality of life. Reduced neuroinflammation and IL-1 signaling provided molecular evidence of the treatment effects.

10.
Nat Commun ; 12(1): 3427, 2021 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-34103518

RESUMEN

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.


Asunto(s)
Péptidos/química , Péptidos/uso terapéutico , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Secuencia de Aminoácidos , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Endocitosis/efectos de los fármacos , Determinación de Punto Final , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ácidos Oléicos/química , Péptidos/farmacología , Placebos , Conformación Proteica , Espectroscopía de Protones por Resonancia Magnética , Termodinámica , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/patología
11.
Nat Rev Urol ; 18(8): 468-486, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34131331

RESUMEN

The most common and lethal bacterial pathogens have co-evolved with the host. Pathogens are the aggressors, and the host immune system is responsible for the defence. However, immune responses can also become destructive, and excessive innate immune activation is a major cause of infection-associated morbidity, exemplified by symptomatic urinary tract infections (UTIs), which are caused, in part, by excessive innate immune activation. Severe kidney infections (acute pyelonephritis) are a major cause of morbidity and mortality, and painful infections of the urinary bladder (acute cystitis) can become debilitating in susceptible patients. Disease severity is controlled at specific innate immune checkpoints, and a detailed understanding of their functions is crucial for strategies to counter microbial aggression with novel treatment and prevention measures. One approach is the use of bacterial molecules that reprogramme the innate immune system, accelerating or inhibiting disease processes. A very different outcome is asymptomatic bacteriuria, defined by low host immune responsiveness to bacteria with attenuated virulence. This observation provides the rationale for immunomodulation as a new therapeutic tool to deliberately modify host susceptibility, control the host response and avoid severe disease. The power of innate immunity as an arbitrator of health and disease is also highly relevant for emerging pathogens, including the current COVID-19 pandemic.


Asunto(s)
Anticuerpos Antivirales/inmunología , COVID-19/epidemiología , Inmunidad Innata , SARS-CoV-2/inmunología , Infecciones Urinarias/diagnóstico , COVID-19/inmunología , Humanos , Pandemias , Índice de Severidad de la Enfermedad , Infecciones Urinarias/epidemiología , Infecciones Urinarias/inmunología
12.
Nat Biotechnol ; 39(6): 754-764, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33574609

RESUMEN

Is the oncogene MYC upregulated or hyperactive? In the majority of human cancers, finding agents that target c-MYC has proved difficult. Here we report specific bacterial effector molecules that inhibit cellular MYC (c-MYC) in human cells. We show that uropathogenic Escherichia coli (UPEC) degrade the c-MYC protein and attenuate MYC expression in both human cells and animal tissues. c-MYC protein was rapidly degraded by both cell-free bacterial lysates and the purified bacterial protease Lon. In mice, intravesical or peroral delivery of Lon protease delayed tumor progression and increased survival in MYC-dependent bladder and colon cancer models, respectively. These results suggest that bacteria have evolved strategies to control c-MYC tissue levels in the host and that the Lon protease shows promise for therapeutic targeting of c-MYC in cancer.


Asunto(s)
Neoplasias del Colon/patología , Genes myc , Neoplasias de la Vejiga Urinaria/patología , Escherichia coli Uropatógena/enzimología , Enfermedad Aguda , Animales , Modelos Animales de Enfermedad , Infecciones por Escherichia coli/patología , Eliminación de Gen , Ratones , Nefritis/genética
13.
J Clin Invest ; 131(4)2021 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-33320835

RESUMEN

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.


Asunto(s)
Infecciones por Escherichia coli , Proteínas de Escherichia coli , Escherichia coli , Regulación Bacteriana de la Expresión Génica/inmunología , Lipoproteínas , ARN Polimerasa II , Infecciones Urinarias , Animales , Línea Celular Tumoral , Escherichia coli/genética , Escherichia coli/inmunología , Infecciones por Escherichia coli/genética , Infecciones por Escherichia coli/inmunología , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/inmunología , Femenino , Humanos , Lipoproteínas/genética , Lipoproteínas/inmunología , Ratones , ARN Polimerasa II/genética , ARN Polimerasa II/inmunología , Infecciones Urinarias/genética , Infecciones Urinarias/inmunología
14.
Mol Biol Evol ; 37(11): 3083-3093, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-32521018

RESUMEN

A challenging question in evolutionary theory is the origin of cell division and plausible molecular mechanisms involved. Here, we made the surprising observation that complexes formed by short alpha-helical peptides and oleic acid can create multiple membrane-enclosed spaces from a single lipid vesicle. The findings suggest that such complexes may contain the molecular information necessary to initiate and sustain this process. Based on these observations, we propose a new molecular model to understand protocell division.


Asunto(s)
Células Artificiales/química , División Celular , Lactalbúmina/química , Membranas/química , Ácido Oléico/química , Vesículas Citoplasmáticas/química , Péptidos/química
15.
Int J Cancer ; 147(9): 2479-2492, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-32319672

RESUMEN

Potent chemotherapeutic agents are required to counteract the aggressive behavior of cancer cells and patients often experience severe side effects, due to tissue toxicity. Our study addresses if a better balance between efficacy and toxicity can be attained using the tumoricidal complex alpha1-oleate, formed by a synthetic, alpha-helical peptide comprising the N-terminal 39 amino acids of alpha-lactalbumin and the fatty acid oleic acid. Bladder cancer was established, by intravesical instillation of MB49 cells on day 0 and the treatment group received five instillations of alpha1-oleate (1.7-17 mM) on days 3 to 11. A dose-dependent reduction in tumor size, bladder size and bladder weight was recorded in the alpha1-oleate treated group, compared to sham-treated mice. Tumor markers Ki-67, Cyclin D1 and VEGF were inhibited in a dose-dependent manner, as was the expression of cancer-related genes. Remarkably, toxicity for healthy tissue was not detected in alpha1-oleate-treated, tumor-bearing mice or healthy mice or rabbits, challenged with increasing doses of the active complex. The results define a dose-dependent therapeutic effect of alpha1-oleate in a murine bladder cancer model.


Asunto(s)
Antineoplásicos/administración & dosificación , Lactalbúmina/administración & dosificación , Ácido Oléico/administración & dosificación , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Vejiga Urinaria/efectos de los fármacos , Administración Intravesical , Animales , Antineoplásicos/química , Antineoplásicos/toxicidad , Línea Celular Tumoral/trasplante , Modelos Animales de Enfermedad , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Lactalbúmina/química , Lactalbúmina/toxicidad , Ratones , Ácido Oléico/química , Ácido Oléico/toxicidad , Conejos , Pruebas de Toxicidad Subcrónica , Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/patología
16.
PLoS Pathog ; 15(6): e1007671, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31181116

RESUMEN

Pathogens rely on a complex virulence gene repertoire to successfully attack their hosts. We were therefore surprised to find that a single fimbrial gene reconstitution can return the virulence-attenuated commensal strain Escherichia coli 83972 to virulence, defined by a disease phenotype in human hosts. E. coli 83972pap stably reprogrammed host gene expression, by activating an acute pyelonephritis-associated, IRF7-dependent gene network. The PapG protein was internalized by human kidney cells and served as a transcriptional agonist of IRF-7, IFN-ß and MYC, suggesting direct involvement of the fimbrial adhesin in this process. IRF-7 was further identified as a potent upstream regulator (-log (p-value) = 61), consistent with the effects in inoculated patients. In contrast, E. coli 83972fim transiently attenuated overall gene expression in human hosts, enhancing the effects of E. coli 83972. The inhibition of RNA processing and ribosomal assembly indicated a homeostatic rather than a pathogenic end-point. In parallel, the expression of specific ion channels and neuropeptide gene networks was transiently enhanced, in a FimH-dependent manner. The studies were performed to establish protective asymptomatic bacteriuria in human hosts and the reconstituted E. coli 83972 variants were developed to improve bacterial fitness for the human urinary tract. Unexpectedly, P fimbriae were able to drive a disease response, suggesting that like oncogene addiction in cancer, pathogens may be addicted to single super-virulence factors.


Asunto(s)
Adhesinas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Proteínas Fimbrias/metabolismo , Fimbrias Bacterianas/metabolismo , Adhesinas de Escherichia coli/genética , Línea Celular , Escherichia coli/genética , Escherichia coli/patogenicidad , Femenino , Proteínas Fimbrias/genética , Fimbrias Bacterianas/genética , Humanos , Factor 7 Regulador del Interferón/metabolismo , Interferón beta/metabolismo , Riñón/metabolismo , Riñón/microbiología , Proteínas Proto-Oncogénicas c-myc/metabolismo
17.
J Mol Biol ; 431(14): 2612-2627, 2019 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-31082436

RESUMEN

As chaperones, heat shock proteins (HSPs) protect host cells against misfolded proteins that constitute a by-product of protein synthesis. Certain HSPs are also expressed on the surface of tumor cells, possibly to scavenge extracellular unfolded protein ligands and prevent them from becoming cytotoxic. HAMLET-a complex of partially unfolded alpha-lactalbumin and oleic acid-is relying on its N-terminal alpha-helical domain to perturb tumor cell membranes, and the cells die as a consequence of this interaction. Here we show that in parallel, cell surface HSPs bind the beta-sheet domain of alpha-lactalbumin and activate a temporarily protective loop, involving vesicular uptake and lysosomal accumulation. Later, HAMLET destroys lysosomal membrane integrity, and HAMLET release kills the remaining tumor cells. HSPs were identified as HAMLET targets in a proteomic screen and Hsp70-specific antibodies or shRNAs inhibited HAMLET uptake by tumor cells, which showed increased Hsp70 surface expression compared to differentiated cells. The results suggest that HAMLET engages tumor cells by two parallel recognition mechanisms, defined by alpha-helical- or beta-sheet domains of alpha-lactalbumin and resulting in an immediate death response, or a delay due to transient accumulation of the complex in the lysosomes. This dual response pattern was conserved among tumor cells but not seen in normal, differentiated cells. By two different mechanisms, HAMLET thus achieves a remarkably efficient elimination of tumor cells.


Asunto(s)
Apoptosis/efectos de los fármacos , Proteínas de Choque Térmico/química , Proteínas de Choque Térmico/metabolismo , Neoplasias Renales/patología , Lactalbúmina/farmacología , Neoplasias Pulmonares/patología , Ácidos Oléicos/farmacología , Conformación Proteica en Lámina beta/efectos de los fármacos , Secuencia de Aminoácidos , Antineoplásicos/farmacología , Humanos , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Estructura Secundaria de Proteína , Células Tumorales Cultivadas
18.
Sci Rep ; 8(1): 11015, 2018 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-30030504

RESUMEN

The nervous system is engaged by infection, indirectly through inflammatory cascades or directly, by bacterial attack on nerve cells. Here we identify a neuro-epithelial activation loop that participates in the control of mucosal inflammation and pain in acute cystitis. We show that infection activates Neurokinin-1 receptor (NK1R) and Substance P (SP) expression in nerve cells and bladder epithelial cells in vitro and in vivo in the urinary bladder mucosa. Specific innate immune response genes regulated this mucosal response, and single gene deletions resulted either in protection (Tlr4-/- and Il1b-/- mice) or in accentuated bladder pathology (Asc-/- and Nlrp3-/- mice), compared to controls. NK1R/SP expression was lower in Tlr4-/- and Il1b-/- mice than in C56BL/6WT controls but in Asc-/- and Nlrp3-/- mice, NK1R over-activation accompanied the exaggerated disease phenotype, due, in part to transcriptional de-repression of Tacr1. Pharmacologic NK1R inhibitors attenuated acute cystitis in susceptible mice, supporting a role in disease pathogenesis. Clinical relevance was suggested by elevated urine SP levels in patients with acute cystitis, compared to patients with asymptomatic bacteriuria identifying NK1R/SP as potential therapeutic targets. We propose that NK1R and SP influence the severity of acute cystitis through a neuro-epithelial activation loop that controls pain and mucosal inflammation.


Asunto(s)
Cistitis/patología , Células Neuroepiteliales/fisiología , Receptores de Neuroquinina-1/metabolismo , Adulto , Animales , Cistitis/inmunología , Femenino , Expresión Génica/efectos de los fármacos , Humanos , Inmunidad Mucosa/fisiología , Inflamación/patología , Interleucina-1beta/genética , Macrófagos , Masculino , Ratones , Ratones Endogámicos C57BL , Mucositis/patología , Músculo Liso/metabolismo , Células Neuroepiteliales/metabolismo , Neutrófilos , Dolor/patología , Sustancia P/metabolismo , Receptor Toll-Like 4/genética , Vejiga Urinaria/metabolismo , Vejiga Urinaria/patología
19.
Biochem Biophys Res Commun ; 482(3): 454-458, 2017 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-28212731

RESUMEN

HAMLET (Human Alpha-lactalbumin Made LEthal to Tumor cells) is a tumoricidal protein-lipid complex with broad effects against cancer cells of different origin. The therapeutic potential is emphasized by a high degree of specificity for tumor tissue. Here we review early studies of HAMLET, in collaboration with the Orrenius laboratory, and some key features of the subsequent development of the HAMLET project. The early studies focused on the apoptotic response that accompanies death in HAMLET treated tumor cells and the role of mitochondria in this process. In subsequent studies, we have identified a sequence of interactions that starts with the membrane integration of HAMLET and the activation of ion fluxes followed by HAMLET internalization, progressive inhibition of MAPK kinases and GTPases and sorting of HAMLET to different cellular compartments, including the nuclei. Therapeutic efficacy of HAMLET has been demonstrated in animal models of glioblastoma, bladder cancer and intestinal cancer. In clinical studies, HAMLET has been shown to target skin papillomas and bladder cancers. The findings identify HAMLET as a new drug candidate with promising selectivity for cancer cells and a strong therapeutic potential.


Asunto(s)
Antineoplásicos/farmacología , Lactalbúmina/farmacología , Ácidos Oléicos/farmacología , Animales , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Cromatina/efectos de los fármacos , Humanos , Transporte Iónico/efectos de los fármacos , Lactalbúmina/química , Modelos Moleculares , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Neoplasias/prevención & control , Ácidos Oléicos/química , Oncogenes , Inhibidores de Proteasoma/farmacología , Inhibidores de Proteínas Quinasas/farmacología
20.
Bio Protoc ; 7(3): e2129, 2017 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-34458450

RESUMEN

This urinary tract infection model was used to monitor the efficacy of a new virulence factor of the uropathogenic Escherichia coli strain CFT073 in vivo. The new virulence factor which we designated TIR-containing protein C (TcpC) blocks Toll-like receptor signaling and the NLRP3 inflammasome signaling cascade by interacting with key components of both pattern recognition receptor systems ( Cirl et al., 2008 ; Waldhuber et al., 2016 ). We infected wild type and knock-out mice with wildtype CFT073 and a mutant CFT073 strain lacking tcpC. This protocol describes how the mice were infected, how CFT073 was prepared and how the infection was monitored. The protocol was derived from our previously published work and allowed us to demonstrate that TcpC is a powerful virulence factor by increasing the bacterial burden of CFT073 in the urine and kidneys. Moreover, TcpC was responsible for the development of kidney abscesses since infection of mice with wildtype but not tcpC-deficient CFT073 mutants caused this complication.

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