RESUMEN
The kallikrein-related peptidase KLK2 has restricted expression in the prostate luminal epithelium, and its protein target is unknown. The present work reports the hydrolytic activities of KLK2 on libraries of fluorescence resonance energy-transfer peptides from which the sequence SYRIF was the most susceptible substrate for KLK2. The sequence SYRIF is present at the extracellular N-terminal segment (58SYRIF63Q) of IL-10R2. KLK2 was fully active at pH 8.0-8.2, found only in prostate inflammatory conditions, and strongly activated by sodium citrate and glycosaminoglycans, the quantities and structures controlled by prostate cells. Bone-marrow-derived macrophages (BMDM) have IL-10R2 expressed on the cell surface, which is significantly reduced after KLK2 treatment, as determined by flow cytometry (FACS analysis). The IL-10 inhibition of the inflammatory response to LPS/IFN-γ in BMDM cells due to decreased nitric oxide, TNF-α, and IL-12 p40 levels is significantly reduced upon treatment of these cells with KLK2. Similar experiments with KLK3 did not show these effects. These observations indicate that KLK2 proteolytic activity plays a role in prostate inflammation and makes KLK2 a promising target for prostatitis treatment.
Asunto(s)
Calicreínas , Humanos , Masculino , Calicreínas/metabolismo , Calicreínas/química , Arginina/metabolismo , Arginina/química , Próstata/metabolismo , Próstata/efectos de los fármacos , Macrófagos/metabolismo , Macrófagos/efectos de los fármacos , Animales , Ratones , Péptidos/química , Péptidos/farmacología , Péptidos/metabolismo , Dominios Proteicos , Interleucina-10/metabolismo , Especificidad por SustratoRESUMEN
Epidemiological studies show a strong correlation between diabetes and the increased risk of developing different cancers, including melanoma. In the present study, we investigated the impact of a streptozotocin (STZ)-induced hyperglycemic environment on B16F10-Nex2 murine melanoma development. Hyperglycemic male C57Bl/6 mice showed increased subcutaneous tumor development, partially inhibited by metformin. Tumors showed increased infiltrating macrophages, and augmented IL-10 and nitric oxide (NO) concentrations. In vivo neutralization of IL-10, NO synthase inhibition, and depletion of macrophages reduced tumor development. STZ-treated TLR4 KO animals showed delayed tumor development; the transfer of hyperglycemic C57Bl/6 macrophages to TLR4 KO reversed this effect. Increased concentrations of IL-10 present in tumor homogenates of hyperglycemic mice induced a higher number of pre-angiogenic structures in vitro, and B16F10-Nex2 cells incubated with different glucose concentrations in vitro produced increased levels of IL-10. In summary, our findings show that a hyperglycemic environment stimulates murine melanoma B16F10-Nex2 primary tumor growth, and this effect is dependent on tumor cell stimulation, increased numbers of macrophages, and augmented IL-10 and NO concentrations. These findings show the involvement of tumor cells and other components of the tumor microenvironment in the development of subcutaneous melanoma under hyperglycemic conditions, defining novel targets for melanoma control in diabetic patients.
Asunto(s)
Hiperglucemia , Interleucina-10 , Macrófagos , Melanoma Experimental , Ratones Endogámicos C57BL , Óxido Nítrico , Animales , Interleucina-10/metabolismo , Óxido Nítrico/metabolismo , Masculino , Hiperglucemia/metabolismo , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Macrófagos/metabolismo , Macrófagos/efectos de los fármacos , Ratones , Ratones Noqueados , Línea Celular TumoralRESUMEN
Neurotoxicity of amyloid beta (Aß) species generated in early stages of aggregation has been associated with development of Alzheimer's disease (AD). Consequently, the field of action of compounds that can identify and inhibit the formation of these species has enlarged considerably. This study investigates the effect and influence of the luminescent, water soluble metal complex cis-[Ru(phen)2(3,4Apy)2]2+ (RuApy, 3,4Apy = 3,4-diaminopyridine, phen = 1,10-phenanthroline) on the aggregation process and toxicity of Aß1-40 and its Aß1-28, Aß11-22 and Aß29-40 fragments since their early stages. The absence of correlation between the conformations generated by Aß fragments and the full length 1-40 peptide during aggregation and the absence of toxicity of Aß fragments to PC12 cells in all stages of aggregation indicated that the aggregation pathway and toxicity found to the full-length Aß1-40 depends on specific interactions between the three fragments. The toxicity of Aß1-40 was dependent on the aggregation step investigated: species generated at the beginning (15 min) of aggregation were toxic, whereas mature (120 min) fibrils were not. The RuApy complex is not toxic to PC12 cells up to 60 µM, and does not interfere with the aggregation pathway of the Aß fragments, but interferes with the aggregation of Aß1-40 and protects the PC12 cells, maintaining 100% of cell viability against the toxicity of Aß1-40 species generated in early stages of aggregation.
Asunto(s)
Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Complejos de Coordinación/farmacología , Agregación Patológica de Proteínas/metabolismo , Rutenio/farmacología , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/efectos de los fármacos , Animales , Supervivencia Celular/efectos de los fármacos , Complejos de Coordinación/química , Microscopía Electrónica de Transmisión , Células PC12 , Fragmentos de Péptidos/efectos de los fármacos , Fragmentos de Péptidos/metabolismo , Agregación Patológica de Proteínas/patología , Ratas , Rutenio/química , Solubilidad , Agua/químicaRESUMEN
kin17 has been described as a protein involved in the processes of DNA replication initiation, DNA recombination, and DNA repair. kin17 has been studied as a potential molecular marker of breast cancer. This work reports the detection and localization of this protein in the murine melanoma cell line B16F10-Nex2 and in two derived subclones with different metastatic potential, B16-8HR and B16-10CR. Nuclear and chromatin-associated protein fractions were analyzed, and kin17 was detected in all fractions, with an elevated concentration observed in the chromatin-associated fraction of the clone with low metastatic potential, suggesting that the kin17 expression level could be a marker of melanoma.