RESUMEN
Transcription factor (TF) recruitment to chromatin is central to activation of transcription. TF-chromatin interactions are highly dynamic, which are evaluated by recovery half time (t1/2) in seconds, determined by fluorescence recovery experiments in living cells, and chromatin immunoprecipitation (ChIP) analysis, measured in minutes. These two states are related: the larger the t1/2, the longer the ChIP occupancy resulting in increased transcription. Here we present data showing that this relationship does not always hold. We found that histone deacetylase inhibitors (HDACis) significantly increased t1/2 of green fluorescent protein (GFP) fused androgen receptor (AR) on a tandem array of positive hormone response elements (HREs) in chromatin. This resulted in increased ChIP signal of GFP-AR. Unexpectedly, however, transcription was inhibited. In contrast, the GFP-fused glucocorticoid receptor (GR), acting through the same HREs, displayed a profile consistent with current models. We provide evidence that these differences are mediated, at least in part, by HDACs. Our results provide insight into TF action in living cells and show that very closely related TFs may trigger significantly divergent outcomes at the same REs.
Asunto(s)
Adenocarcinoma/metabolismo , Regulación Neoplásica de la Expresión Génica , Neoplasias Mamarias Animales/metabolismo , Receptores Androgénicos/metabolismo , Receptores de Glucocorticoides/metabolismo , Elementos de Respuesta/genética , Activación Transcripcional/genética , Adenocarcinoma/genética , Anciano , Animales , Inmunoprecipitación de Cromatina , Femenino , Técnica del Anticuerpo Fluorescente , Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas/química , Humanos , Neoplasias Mamarias Animales/genética , Ratones , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores Androgénicos/genética , Receptores de Glucocorticoides/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales CultivadasRESUMEN
Direct modulation of gene expression by targeting oncogenic transcription factors is a new area of research for cancer treatment. ERG, an ETS-family transcription factor, is commonly over-expressed or translocated in leukaemia and prostate carcinoma. In this work, we selected the di-(thiophene-phenyl-amidine) compound DB1255 as an ERG/DNA binding inhibitor using a screening test of synthetic inhibitors of the ERG/DNA interaction followed by electrophoretic mobility shift assays (EMSA) validation. Spectrometry, footprint and biosensor-surface plasmon resonance analyses of the DB1255/DNA interaction evidenced sequence selectivity and groove binding as dimer. Additional EMSA evidenced the precise DNA-binding sequence required for optimal DB1255/DNA binding and thus for an efficient ERG/DNA complex inhibition. We further highlighted the structure activity relationships from comparison with derivatives. In cellulo luciferase assay confirmed this modulation both with the constructed optimal sequences and the Osteopontin promoter known to be regulated by ERG and which ERG-binding site was protected from DNaseI digestion on binding of DB1255. These data showed for the first time the ERG/DNA complex modulation, both in vitro and in cells, by a heterocyclic diamidine that specifically targets a portion of the ERG DNA recognition site.
Asunto(s)
Amidinas/farmacología , Antineoplásicos/farmacología , Tiofenos/farmacología , Transactivadores/antagonistas & inhibidores , Activación Transcripcional/efectos de los fármacos , Amidinas/química , Amidinas/metabolismo , Antineoplásicos/química , Antineoplásicos/metabolismo , Sitios de Unión , Línea Celular Tumoral , ADN/química , ADN/metabolismo , Evaluación Preclínica de Medicamentos , Humanos , Tiofenos/química , Tiofenos/metabolismo , Transactivadores/metabolismo , Regulador Transcripcional ERGRESUMEN
There is a therapeutic need for glucocorticoid receptor (GR) ligands that distinguish between the transrepression and transactivation activity of the GR, the later thought to be responsible for side effects. These ligands are known as "dissociated glucocorticoids" (dGCs). The first published dGCs, RU24782 (9α-fluoro-11ß-hydroxy-16α-methylpregna-21-thiomethyl-1,4-diene-3,20-dione) and RU24858 (9α-fluoro-11ß-hydroxy-16α-methylpregna-21-cyanide-1,4-diene-3,20-dione), do not have the 17α-hydroxyl group that characterizes dexamethasone (Dex; 9α-fluoro-11ß,17α,21-trihydroxy-16α-methylpregna-1,4-diene-3,20-dione), and they differ from one another by having C21-thiomethyl and C21-cyanide moieties, respectively. Our aim was therefore to establish the structural basis of their activity. Both RU24782 and RU24858 induced a transactivation activity highly dependent on the GR expression level but always lower than dexamethasone. They also display less ability than dexamethasone to trigger steroid receptor coactivator 1 (SRC-1) recruitment and histone H3 acetylation. Docking studies, validated by mutagenesis experiments, revealed that dGCs are not anchored by Gln642, in contrast to Dex, which is hydrogen bonded to this residue via its 17α-hydroxyl group. This contact is essential for SRC-1 recruitment and subsequent dexamethasone-induced GR transactivation, but not transrepression. The ability of dGCs to make contacts with Ile747, for both RU24858 and RU24782 and with Asn564 for RU24858 are not strong enough to maintain GR in a conformation able to efficiently recruit SRC-1, unless SRC-1 is overexpressed. Overall, our findings provide some structural guidelines for the synthesis of potential new dissociated glucocorticoids with a better therapeutic ratio.
Asunto(s)
Glucocorticoides/farmacología , Receptores de Glucocorticoides/genética , Activación Transcripcional/efectos de los fármacos , Transporte Activo de Núcleo Celular , Animales , Sitios de Unión , Células COS , Células Cultivadas , Chlorocebus aethiops , Dexametasona/farmacología , Glucocorticoides/química , Glucocorticoides/metabolismo , Humanos , Coactivador 1 de Receptor Nuclear/fisiología , Regiones Promotoras Genéticas , Conformación Proteica , Receptores de Glucocorticoides/química , Receptores de Glucocorticoides/metabolismo , Factores de Transcripción/genéticaRESUMEN
This work concerns the successful enantiomeric separation of pyroglutamic acid derivatives, known to be P2X7 receptor antagonists, achieved by electrokinetic chromatography. After a broad screening, two negatively charged cyclodextrins, sulfobutylether-ß-cyclodextrin (SBE-ß-CD), and highly sulfated-γ-cyclodextrin (HS-γ-CD) were chosen as stereoselective agents to cooperate with the BGE for complexation. A fused silica capillary coated with polyethylene oxide, filled with a phosphate buffer (25 mM, pH 2.5) containing various concentrations of CD, was used. Assuming a 1:1 stoichiometry, calculations of the binding constants, employing the three different linearization plots, were performed from the corrected electrophoretic mobilities values of the enantiomers, at different concentrations of SBE-ß-CD and HS-γ-CD in the BGE. The highest complexation was found with the SBE-ß-CD. Among the three equations, results showed better linearity (R(2) > 0.99) using the y-reciprocal fit. This plotting method was then performed to determine the binding constants of each enantiomer at different temperature for compounds 1 and 2 with SBE-ß-CD and HS-γ-CD in order to access to the thermodynamic parameters of the eight complexes. The linearity of the Van't Hoff plot, in the range of 288-303 K leading to negative enthalpy values, showed that the complexation phenomenon is enthalpically controlled and thermodynamically favored.
Asunto(s)
Cromatografía Capilar Electrocinética Micelar/métodos , Antagonistas Purinérgicos/química , Antagonistas Purinérgicos/aislamiento & purificación , gamma-Ciclodextrinas/química , Reproducibilidad de los Resultados , Estereoisomerismo , TermodinámicaRESUMEN
Immuno-therapy has become a leading strategy to fight cancer. Over the past few years, immuno-therapies using checkpoint inhibitor monoclonal antibodies (mAbs) against programmed death receptor 1 (PD-1) and programmed death ligand 1 (PD-L1) have demonstrated improved survival compared with chemotherapy. We describe the microwave-assisted synthesis and the characterization of an innovative series of synthetic compounds endowed with nanomolar activity against PD-L1. The properties of the compounds were characterized using several biophysical techniques including microscale thermophoresis (MST) and fluorescence resonance energy transfer (FRET) measurements. A few small molecules demonstrated a high affinity for human PD-L1, potently disrupted the PD-L1:PD-1 interaction and inhibited Src homology region 2 domain-containing phosphatase (SHP2) recruitment to PD-1. More than 30 molecules from the pyrazolone family have been synthesized and 5 highly potent "PD-L1 silencing compounds" have been identified, based on in vitro measurements. Structure-activity relationships have been defined and ADME properties were evaluated. The phenyl-pyrazolone unit offers novel perspectives to design PD-L1-targeting agents, potentially useful to combat cancer and other pathologies implicating the PD-1/PD-L1 checkpoint.
Asunto(s)
Inhibidores de Puntos de Control Inmunológico , Neoplasias , Pirazolonas , Antígeno B7-H1 , Humanos , Ligandos , Receptor de Muerte Celular Programada 1 , Pirazolonas/farmacologíaRESUMEN
Only a subpopulation of non-small cell lung cancer (NSCLC) patients responds to immunotherapies, highlighting the urgent need to develop therapeutic strategies to improve patient outcome. We develop a chemical positive modulator (HEI3090) of the purinergic P2RX7 receptor that potentiates αPD-1 treatment to effectively control the growth of lung tumors in transplantable and oncogene-induced mouse models and triggers long lasting antitumor immune responses. Mechanistically, the molecule stimulates dendritic P2RX7-expressing cells to generate IL-18 which leads to the production of IFN-γ by Natural Killer and CD4+ T cells within tumors. Combined with immune checkpoint inhibitor, the molecule induces a complete tumor regression in 80% of LLC tumor-bearing mice. Cured mice are also protected against tumor re-challenge due to a CD8-dependent protective response. Hence, combination treatment of small-molecule P2RX7 activator followed by immune checkpoint inhibitor represents a strategy that may be active against NSCLC.
Asunto(s)
Carcinoma Pulmonar de Lewis/terapia , Inhibidores de Puntos de Control Inmunológico/farmacología , Inmunoterapia/métodos , Receptores Purinérgicos P2X7/inmunología , Bibliotecas de Moléculas Pequeñas/farmacología , Animales , Carcinoma Pulmonar de Lewis/genética , Carcinoma Pulmonar de Lewis/inmunología , Línea Celular Tumoral , Terapia Combinada , Femenino , Células HEK293 , Humanos , Inhibidores de Puntos de Control Inmunológico/inmunología , Interferón gamma/inmunología , Interferón gamma/metabolismo , Interleucina-18/genética , Interleucina-18/inmunología , Interleucina-18/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Estructura Molecular , Receptores Purinérgicos P2X7/genética , Receptores Purinérgicos P2X7/metabolismo , Bibliotecas de Moléculas Pequeñas/química , Análisis de Supervivencia , Carga Tumoral/efectos de los fármacos , Carga Tumoral/inmunologíaRESUMEN
This report deals with the design, the synthesis, and the pharmacological evaluation of pyroglutamide-based P2X7 antagonists. A dozen were shown to possess improved properties, among which inhibition of YO-PRO-1/TO-PRO-3 uptake and IL1ß release upon BzATP activation of the receptor and dampening signs of DSS-induced colitis on mice, in comparison with reference antagonist GSK1370319A. Docking study and biological evaluation of synthesized compounds has highlighted new SAR, and low toxicity profiles of pyroglutamides herein described are clues for the finding of a usable h-P2X7 antagonist drug. Such a drug would raise the hope for a cure to many P2X7-dependent pathologies, including inflammatory, neurological, and immune diseases.
Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/metabolismo , Antagonistas del Receptor Purinérgico P2X/administración & dosificación , Antagonistas del Receptor Purinérgico P2X/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Animales , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Sulfato de Dextran/toxicidad , Femenino , Células HEK293 , Humanos , Enfermedades Inflamatorias del Intestino/inducido químicamente , Ratones , Ratones Endogámicos C57BLRESUMEN
BACKGROUND: Chronic ER stress and dysfunction is a hallmark of obesity and a critical contributor to metaflammation, abnormal hormone action and altered substrate metabolism in metabolic tissues, such as liver and adipocytes. Lack of STAMP2 in lean mice induces inflammation and insulin resistance on a regular diet, and it is dysregulated in the adipose tissue of obese mice and humans. We hypothesized that the regulation of STAMP2 is disrupted by ER stress. METHODS: 3T3-L1 and MEF adipocytes were treated with ER stress inducers thapsigargin and tunicamycin, and inflammation inducer TNFα. The treatments effect on STAMP2 expression and enzymatic function was assessed. In addition, 3T3-L1 adipocytes and HEK cells were utilized for Stamp2 promoter activity investigation performed with luciferase and ChIP assays. RESULTS: ER stress significantly reduced both STAMP2 mRNA and protein expression in cultured adipocytes whereas TNFα had the opposite effect. Concomitant with loss of STAMP2 expression during ER stress, intracellular localization of STAMP2 was altered and total iron reductase activity was reduced. Stamp2 promoter analysis by reporter assays and chromatin immunoprecipitation, showed that induction of ER stress disrupts C/EBPα-mediated STAMP2 expression. CONCLUSION: These data suggest a clear link between ER stress and quantitative and functional STAMP2-deficiency.
Asunto(s)
Adipocitos/metabolismo , Estrés del Retículo Endoplásmico , Inflamación/metabolismo , Proteínas de la Membrana/metabolismo , Adipocitos/patología , Animales , Células Cultivadas , Estrés del Retículo Endoplásmico/efectos de los fármacos , Inflamación/inducido químicamente , Proteínas de la Membrana/análisis , Proteínas de la Membrana/deficiencia , Ratones , ARN Mensajero/análisis , Tapsigargina/farmacología , Factor de Necrosis Tumoral alfa/farmacologíaRESUMEN
Ferrocene analogs of known fatty acid amide hydrolase inhibitors and CB2 ligands have been synthesized and characterized spectroscopically and crystallographically. The resulting bio-organometallic isoxazoles were assayed for their effects on CB1 and CB2 receptors as well as on fatty acid amide hydrolase. None had any fatty acid amide hydrolase activity but compound 3, 5-(2-(pentyloxy)phenyl)-N-ferrocenylisoxazole-3-carboxamide, was found to be a potent CB2 ligand (Ki = 32.5 nM).
Asunto(s)
Compuestos Ferrosos/química , Metalocenos/química , Receptor Cannabinoide CB2/química , Amidohidrolasas/antagonistas & inhibidores , Amidohidrolasas/metabolismo , Sitios de Unión , Compuestos Ferrosos/síntesis química , Compuestos Ferrosos/metabolismo , Humanos , Ligandos , Metalocenos/síntesis química , Metalocenos/metabolismo , Conformación Molecular , Simulación del Acoplamiento Molecular , Unión Proteica , Receptor Cannabinoide CB1/química , Receptor Cannabinoide CB1/metabolismo , Receptor Cannabinoide CB2/metabolismoRESUMEN
A series of novel oxazolo[5,4-d]pyrimidines was designed via a scaffold hopping strategy and synthesized through a newly developed approach. All these compounds were evaluated for their biological activity toward CB1/CB2 cannabinoid receptors, their metabolic stability in mice liver microsomes and their cytotoxicity against several cell lines. Eight compounds have been identified as CB2 ligands with Ki values less than 1⯵M. It is noteworthy that 2-(2-chlorophenyl)-5-methyl-7-(4-methylpiperazin-1-yl) oxazolo[5,4-d]pyrimidine 47 and 2-(2-chlorophenyl)-7-(4-ethylpiperazin-1-yl)- 5-methyloxazolo[5,4-d]pyrimidine 48 showed CB2 binding affinity in the nanomolar range and significant selectivity over CB1 receptors. Interestingly, functionality studies imply that they behave as competitive neutral antagonists. Moreover, all tested compounds are devoid of cytotoxicity toward several cell lines, including Chinese hamster ovary cells (CHO) and human colorectal adenocarcinoma cells HT29.
Asunto(s)
Oxazoles/farmacología , Pirimidinas/farmacología , Receptor Cannabinoide CB2/antagonistas & inhibidores , Animales , Unión Competitiva/efectos de los fármacos , Células CHO , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Cricetulus , Relación Dosis-Respuesta a Droga , Células HT29 , Humanos , Masculino , Ratones , Microsomas Hepáticos/química , Microsomas Hepáticos/metabolismo , Estructura Molecular , Oxazoles/síntesis química , Oxazoles/química , Pirimidinas/síntesis química , Pirimidinas/química , Receptor Cannabinoide CB2/metabolismo , Relación Estructura-ActividadRESUMEN
The P2X receptors are seven-transmembrane domain G protein-coupled receptors and the 7 subtypes of P2X receptors identified in humans, and named P2X1 to P2X7, are channel receptors whose endogenous ligand is ATP. New antagonists of the P2X7 receptor were developed, since this purinergic receptor was highlighted to be involved in many diseases such as different types of pain, cancer, ischemia, neurodegenerative diseases (including Parkinson's and Alzheimer's diseases) characterized by inflammatory processes. With the aim of evaluate the impact of chirality on the pharmacological activity of a new P2X7R antagonist, a semi-preparative method was developed in supercritical fluid chromatography (SFC). Among four polysaccharide based chiral stationary phases: Chiralcel OD-H and OJ-H and Chiralpak AS-H and AD-H, the last one namely amylose tris (3,5-dimethylphenylcarbamate) with a mobile phase consisted of carbon dioxide-ethanol (80:20, v/v), led to the successful separation of the enantiomers in short run time and with good resolution. Limits of detection and quantification were calculated and were found equal for compound 1, to 1.37 µM and 4.57 µM respectively, for peak 1 and were equal to 1.60 µM and 5.30 µM respectively, for peak 2 at λ=210 nm. Before carrying out the pharmacological evaluation of each enantiomer, two complementary methodologies, e.g. liquid chromatography and capillary electrophoresis were performed in parallel to improve the limits of detection and quantification to assess the enantiomeric purity. HPLC using a Chiralpak AD stationary phase led to four times lower limits of detection and quantification with regard to SFC. In the same time, capillary electrophoresis involving dual cyclodextrins system constituted of a SBE-ß-CD and a MM-ß-CD mixture enhanced the signal-to-noise ratio and led to similar limits of detection and quantification with regard to SFC. No trace of the other enantiomer was found in the isolated one. Biological activities of individual enantiomers were then evaluated and revealed no cytotoxicity against cell lines and a significant difference in terms of their IC50 values with respect to the investigated racemate (6.43 µM): 3.49 µM for the (R)-enantiomer and >10(-4)µM for the (S)-enantiomer, for compound 1, showing that, this antagonist activity is stereospecific.
Asunto(s)
Amilosa/análogos & derivados , Celulosa/análogos & derivados , Cromatografía Líquida de Alta Presión/métodos , Fenilcarbamatos/química , Antagonistas del Receptor Purinérgico P2X/química , Antagonistas del Receptor Purinérgico P2X/aislamiento & purificación , Amilosa/química , Celulosa/química , Modelos Lineales , Antagonistas del Receptor Purinérgico P2X/análisis , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , EstereoisomerismoRESUMEN
Closely related transcription factors (TFs) can bind to the same response elements (REs) with similar affinities and activate transcription. However, it is unknown whether transcription is similarly orchestrated by different TFs bound at the same RE. Here we have compared the recovery half time (t1/2), binding site occupancy and the resulting temporal changes in transcription upon binding of two closely related steroid receptors, the androgen and glucocorticoid receptors (AR and GR), to their common hormone REs (HREs). We show that there are significant differences at all of these levels between AR and GR at the MMTV HRE when activated by their ligands. These data show that two TFs bound at the same RE can have significantly different modes of action that can affect their responses to environmental cues.
Asunto(s)
Receptores Androgénicos/metabolismo , Receptores de Glucocorticoides/metabolismo , Elementos de Respuesta/genética , Western Blotting , Línea Celular , Inmunoprecipitación de Cromatina , Recuperación de Fluorescencia tras Fotoblanqueo , Humanos , Receptores Androgénicos/genética , Receptores de Glucocorticoides/genética , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Analytical enantioseparation of three pyroglutamide derivatives with pharmacological activity against the purinergic receptor P2X7, was run in both high-performance liquid chromatography and supercritical fluid chromatography. Four polysaccharide based chiral stationary phases, namely amylose and cellulose tris (3,5-dimethylphenylcarbamate), amylose tris ((S)-α-methylbenzylcarbamate) and cellulose tris (4-methylbenzoate) with various mobile phases consisted of either heptane/alcohol (ethanol and 2-propanol) or carbon dioxide/alcohol (methanol or ethanol) mixtures, were investigated. After analytical screenings, the best conditions were transposed, for compound 1, to semi-preparative scale. Each approach was fully validated to meet the International Conference on Harmonisation requirements and compared. Whereas the limits of detection and quantification were near six-fold better in HPLC than in SFC (respectively 0.20 and 0.66 µM versus 1.11 and 3.53 µM for one of the enantiomers), in terms of low solvent consumption (7.2 mL of EtOH versus 3.2 mL of EtOH plus 28.8 mL of toxic and inflammable heptane per injection in SFC and HPLC, respectively), time effective cost (9 min versus 40 min per injection in SFC and HPLC, respectively) and yields (98% versus 71% in SFC and HPLC, respectively), the latter method proved its ecological superiority.
Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Cromatografía con Fluido Supercrítico/métodos , Polisacáridos/química , Ácido Pirrolidona Carboxílico , Receptores Purinérgicos P2X7 , EstereoisomerismoRESUMEN
The ability of inhibitors of transcription and translation to prevent glucocorticoid-induced apoptosis has been interpreted to indicate that the cell death machinery requires de novo protein synthesis. The transcriptional inhibitors actinomycin D (Act D) and DRB as well as the translational inhibitors CHX and puromycin inhibited early loss of mitochondrial membrane integrity in a dose-dependent manner. This effect was not observed with the transcriptional inhibitor α-amanitin suggesting they may have additional effects. Their role in the glucocorticoid receptor (GR) intracellular trafficking was therefore investigated. Here, we show that Act D and CHX reduced glucocorticoid binding, GR turnover and impaired GR nuclear translocation. We performed the same experiments in different thymocyte subpopulations of Balb/c mice. At the highest dose tested, actinomycin D and cycloheximide abolished glucocorticoid-induced cell death of CD4+CD8+ and CD4+CD8-. In all subsets, Act D, DRB, as well as CHX and puromycin prevented receptor nuclear translocation, indicating a general alteration of GR trafficking. Overall, our data support a direct effect of macromolecular inhibitors on GR activation and trafficking. Finally, direct alterations of the functional properties of the glucocorticoid receptor might be responsible for cell death prevention by actinomycin D, DRB, cycloheximide and puromycin.
Asunto(s)
Inhibidores de la Síntesis del Ácido Nucleico/farmacología , Inhibidores de la Síntesis de la Proteína/farmacología , Receptores de Glucocorticoides/metabolismo , Alfa-Amanitina/farmacología , Animales , Células Cultivadas , Cicloheximida/farmacología , Dactinomicina/farmacología , Glucocorticoides/metabolismo , Células HeLa , Humanos , Sustancias Macromoleculares/antagonistas & inhibidores , Sustancias Macromoleculares/metabolismo , Ratones , Ratones Endogámicos BALB C , Unión Proteica , Transporte de Proteínas/efectos de los fármacos , Puromicina/farmacología , Timo/citología , Timo/efectos de los fármacos , Timo/metabolismoRESUMEN
Unlike classical protein extraction techniques, proteomic mapping using a selective subcellular extraction kit revealed S100A11 as a new member of the S100 protein family modulated by glucocorticoids in keratinocytes. Glucocorticoids (GC)-induced S100A11 redistribution in the "organelles and membranes" compartment. Microscopic examination indicated that glucocorticoids specifically routed cytoplasmic S100A11 toward perinuclear compartment. Calcium, a key component of skin terminal differentiation, directed S100A11 to the plasma membrane as previously reported. When calcium was added to glucocorticoids, minor change was observed at the proteomic level while confocal microscopy revealed a rapid and dramatic translocation of S100A11 toward plasma membrane. This effect was accompanied by strong nuclear condensation, loss of mitochondrial potential and DNA content, and increased high molecular weight S100A11 immunoreactivity, suggesting corticoids accelerate calcium-induced terminal differentiation. Finally, our results suggest GC-induced S100A11 relocalization could be a key step in both keratinocyte homeostasis and glucocorticoids side effects in human epidermis.