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Objective We use the dynamic electroencephalography–functional magnetic resonance imaging (EEG-fMRI) method to incorporate variability in the amplitude and field of the interictal epileptic discharges (IEDs) into the fMRI analysis. We ask whether IED variability analysis can (a) identify additional activated brain regions during the course of IEDs, not seen in standard analysis; and (b) demonstrate the origin and spread of epileptic activity. We explore whether these functional changes recapitulate the structural connections and propagation of epileptic activity during seizures. Methods Seventeen patients with focal epilepsy and at least 30 IEDs of a single type during simultaneous EEG-fMRI were studied. IED variability and EEG source imaging (ESI) analysis extracted time-varying dynamic changes. General linear modeling (GLM) generated static functional maps. Dynamic maps were compared to static functional maps. The dynamic sequence from IED variability was compared to the ESI results. In a subset of patients, we investigated structural connections between active brain regions using diffusion-based fiber tractography. Results IED variability distinguished the origin of epileptic activity from its propagation in 15 of 17 (88%) patients. This included two cases where no result was obtained from the standard GLM analysis. In both of these cases, IED variability revealed activation in line with the presumed epileptic focus. Two cases showed no result from either method. Both had very high spike rates associated with dysplasia in the postcentral gyrus. In all 15 cases with dynamic activation, the observed dynamics were concordant with ESI. Fiber tractography identified specific white matter pathways between brain regions that were active at IED onset and propagation. Significance Dynamic techniques involving IED variability can provide additional power for EEG-fMRI analysis, compared to standard analysis, revealing additional biologically plausible information in cases with no result from the standard analysis and gives insight into the origin and spread of IEDs.

Epilepsy is associated with genetic risk factors and cortico-subcortical network alterations, but associations between neurobiological mechanisms and macroscale connectomics remain unclear. This multisite ENIGMA-Epilepsy study examined whole-brain structural covariance networks in patients with epilepsy and related findings to postmortem co-expression patterns of epilepsy risk genes. Brain network analysis included 578 adults with temporal lobe epilepsy (TLE), 288 adults with idiopathic generalized epilepsy (IGE), and 1,328 healthy controls from 18 centres worldwide. Graph theoretical analysis of structural covariance networks revealed increased clustering and path length in orbitofrontal and temporal regions in TLE, suggesting a shift towards network regularization. Conversely, people with IGE showed decreased clustering and path length in fronto-temporo-parietal cortices, indicating a random network configuration. Syndrome-specific topological alterations reflected expression patterns of risk genes for hippocampal sclerosis in TLE and for generalized epilepsy in IGE. These imaging-genetic signatures could guide diagnosis, and ultimately, tailor therapeutic approaches to specific epilepsy syndromes.

Temporal lobe epilepsy (TLE), a common drug-resistant epilepsy in adults, is primarily a limbic network disorder associated with predominant unilateral hippocampal pathology. Structural MRI has provided an in vivo window into whole-brain grey matter pathology in TLE relative to controls, by either mapping (i) atypical inter-hemispheric asymmetry or (ii) regional atrophy. However, similarities and differences of both atypical asymmetry and regional atrophy measures have not been systematically investigated. Here, we addressed this gap using the multi-site ENIGMA-Epilepsy dataset comprising MRI brain morphological measures in 732 TLE patients and 1,418 healthy controls. We compared spatial distributions of grey matter asymmetry and atrophy in TLE, contextualized their topographies relative to spatial gradients in cortical microstructure and functional connectivity, and examined clinical associations using machine learning. We identified a marked divergence in the spatial distribution of atypical inter-hemispheric asymmetry and regional atrophy mapping. The former revealed a temporo-limbic disease signature while the latter showed diffuse and bilateral patterns. Our findings were robust across individual sites and patients. Cortical atrophy was significantly correlated with disease duration and age at seizure onset, while degrees of asymmetry did not show a significant relationship to these clinical variables. Our findings highlight that the mapping of atypical inter-hemispheric asymmetry and regional atrophy tap into two complementary aspects of TLE-related pathology, with the former revealing primary substrates in ipsilateral limbic circuits and the latter capturing bilateral disease effects. These findings refine our notion of the neuropathology of TLE and may inform future discovery and validation of complementary MRI biomarkers in TLE.

Aims\ud The causes of distinct patterns of reduced cortical thickness in the common human epilepsies, detectable on neuroimaging and with important clinical consequences, are unknown. We investigated the underlying mechanisms of cortical thinning using a systems-level analysis.\ud \ud Methods\ud Imaging-based cortical structural maps from a large-scale epilepsy neuroimaging study were overlaid with highly spatially resolved human brain gene expression data from the Allen Human Brain Atlas. Cell-type deconvolution, differential expression analysis and cell-type enrichment analyses were used to identify differences in cell-type distribution. These differences were followed up in post-mortem brain tissue from humans with epilepsy using Iba1 immunolabelling. Furthermore, to investigate a causal effect in cortical thinning, cell-type-specific depletion was used in a murine model of acquired epilepsy.\ud \ud Results\ud We identified elevated fractions of microglia and endothelial cells in regions of reduced cortical thickness. Differentially expressed genes showed enrichment for microglial markers and, in particular, activated microglial states. Analysis of post-mortem brain tissue from humans with epilepsy confirmed excess activated microglia. In the murine model, transient depletion of activated microglia during the early phase of the disease development prevented cortical thinning and neuronal cell loss in the temporal cortex. Although the development of chronic seizures was unaffected, the epileptic mice with early depletion of activated microglia did not develop deficits in a non-spatial memory test seen in epileptic mice not depleted of microglia.\ud \ud Conclusions\ud These convergent data strongly implicate activated microglia in cortical thinning, representing a new dimension for concern and disease modification in the epilepsies, potentially distinct from seizure control.

Brain atrophy in human epilepsy syndromes is explainable by network architecture and strongest in hub regions., Epilepsy is increasingly conceptualized as a network disorder. In this cross-sectional mega-analysis, we integrated neuroimaging and connectome analysis to identify network associations with atrophy patterns in 1021 adults with epilepsy compared to 1564 healthy controls from 19 international sites. In temporal lobe epilepsy, areas of atrophy colocalized with highly interconnected cortical hub regions, whereas idiopathic generalized epilepsy showed preferential subcortical hub involvement. These morphological abnormalities were anchored to the connectivity profiles of distinct disease epicenters, pointing to temporo-limbic cortices in temporal lobe epilepsy and fronto-central cortices in idiopathic generalized epilepsy. Negative effects of age on atrophy further revealed a strong influence of connectome architecture in temporal lobe, but not idiopathic generalized, epilepsy. Our findings were reproduced across individual sites and single patients and were robust across different analytical methods. Through worldwide collaboration in ENIGMA-Epilepsy, we provided deeper insights into the macroscale features that shape the pathophysiology of common epilepsies.

SUMMARYEpilepsy is increasingly conceptualized as a network disorder. In this cross-sectional mega-analysis, we integrated neuroimaging and connectome analysis to identify network associations with atrophy patterns in 1,021 adults with epilepsy compared to 1,564 healthy controls from 19 international sites. In temporal lobe epilepsy, areas of atrophy co-localized with highly interconnected cortical hub regions, whereas idiopathic generalized epilepsy showed preferential subcortical hub involvement. These morphological abnormalities were anchored to the connectivity profiles of distinct disease epicenters, pointing to temporo-limbic cortices in temporal lobe epilepsy and fronto-central cortices in idiopathic generalized epilepsy. Indices of progressive atrophy further revealed a strong influence of connectome architecture on disease progression in temporal lobe, but not idiopathic generalized, epilepsy. Our findings were reproduced across individual sites and single patients, and were robust across different analytical methods. Through worldwide collaboration in ENIGMA-Epilepsy, we provided novel insights into the macroscale features that shape the pathophysiology of common epilepsies.

Objective The aim of this report is to present our clinical experience of electroencephalography–functional magnetic resonance imaging (EEG-fMRI) in localizing the epileptogenic focus, and to evaluate the clinical impact and challenges associated with the use of EEG-fMRI in pharmacoresistant focal epilepsy. Methods We identified EEG-fMRI studies (n = 118) in people with focal epilepsy performed at our center from 2003 to 2018. Participants were referred from our Comprehensive Epilepsy Program in an exploratory research effort to address often difficult clinical questions, due to complex and difficult-to-localize epilepsy. We assessed the success of each study, the clinical utility of the result, and when surgery was performed, the postoperative outcome. Results Overall, 50% of EEG-fMRI studies were successful, meaning that data were of good quality and interictal epileptiform discharges were recorded. With an altered recruitment strategy since 2012 with increased inclusion of patients who were inpatients for video-EEG monitoring, we found that this patients in this selected group were more likely to have epileptic discharges detected during EEG-fMRI (96% of inpatients vs 29% of outpatients, P

Cocaine dependence (CD) is highly comorbid with personality disorders, with implications for poorer treatment response. The neurobiological mechanisms of this comorbidity are unclear. We aimed to test the role of comorbid personality disorders in the neuroanatomy of CD. We examined 4 groups using high-resolution structural neuroimaging, psychological questionnaires and cognitive tests: CD (n = 19), CD and personality disorder type B (CD + B, n = 21), CD and personality disorder C (CD + C, n = 13) and 21 controls. We compared groups in neuroanatomy and hypothesised that (i) CD would show altered striatal areas ascribed to reward processing (i.e., accumbens, caudate and putamen), (ii) CD + B and CD + C would show altered areas supporting emotional regulation/social valuation and anxiety/avoidance (i.e., OFC and amygdala). The CD + B group had larger caudate volumes than CD (p = .01, d = 0.94) and reduced lateral OFC thickness than CD + C (p = .056, d = 0.71). Exploratory correlations showed that altered neural integrity of the OFC and of the caudate nucleus in these groups exacerbated with worse personality disorder severity and impulsivity scores. CD with and without comorbid personality disorders may have partially distinct underlying mechanisms and targets for treatment.

ObjectiveTo examine cerebral cortex thickness in asymptomatic first-degree relatives of patients with mesial temporal lobe epilepsy (MTLE).MethodsWe investigated 127 asymptomatic first-degree relatives of patients with MTLE due to hippocampal sclerosis (HS) (mean age ± SD = 39.4 ± 13 years) and 203 healthy control individuals (mean age ± SD = 36.0 ± 11 years). Participants underwent a comprehensive clinical evaluation and structural brain MRI at 3 study sites. Images were processed simultaneously at each site using a surface-based morphometry method to quantify global brain measures, hippocampal volumes, and cerebral cortical thickness. Differences in brain measures between relatives of patients and controls were examined using generalized models, while controlling for relevant covariates, including age and sex.ResultsNone of the asymptomatic first-degree relatives of MTLE + HS patients showed evidence of HS on qualitative image assessments. Compared to the healthy controls, the asymptomatic relatives of patients displayed no significant differences in intracranial volume, average hemispheric surface area, or hippocampal volume. Similarly, no significant cerebral cortical thinning was identified in the relatives of patients. This was consistent across the 3 cohorts.ConclusionLack of cortical thickness changes in the asymptomatic relatives of patients indicates that the previously characterized MTLE + HS-related cortical thinning is not heritable, and is likely driven by disease-related factors. This finding therefore argues for early and aggressive intervention in patients with medically intractable epilepsy.

ObjectiveThe process of manually marking up epileptic spikes for simultaneous electroencephalogram (EEG) and resting state functional MRI (rsfMRI) analysis in epilepsy studies is a tedious and subjective task for a human expert. The aim of this study was to evaluate whether automatic EEG spike detection can facilitate EEG-rsfMRI analysis, and to assess its potential as a clinical tool in epilepsy.MethodsWe implemented a fast algorithm for detection of uniform interictal epileptiform discharges (IEDs) in one-hour scalp EEG recordings of 19 refractory focal epilepsy datasets (from 16 patients) who underwent a simultaneous EEG-rsfMRI recording. Our method was based on matched filtering of an IED template (derived from human markup) used to automatically detect other ‘similar’ EEG events. We comprehensively compared simultaneous EEG-rsfMRI results between automatic IED detection and standard analysis with human EEG markup only.ResultsIn contrast to human markup, automatic IED detection takes a much shorter time to detect IEDs and export an output text file containing spike timings. In 13/19 focal epilepsy cases, statistical EEG-rsfMRI maps based on automatic spike detection method were comparable with human markup, and in 6/19 focal epilepsy cases it revealed additional brain regions not seen with human EEG markup. Additional events detected by our automated method independently revealed similar patterns of activation to a human markup. Overall, automatic IED detection provides greater statistical power in EEG-rsfMRI analysis compared to human markup in a short timeframe.ConclusionsAutomatic spike detection is a simple and fast method that can reproduce comparable and, in some cases, even superior results compared to the common practice of manual EEG markup in EEG-rsfMRI analysis of epilepsy.SignificanceOur study shows that IED detection algorithms can be effectively used in epilepsy clinical settings. This work further helps in translating EEG-rsfMRI research into a fast, reliable and easy-to-use clinical tool for epileptologists. Our IED detection approach will be publicly available as a MATLAB package at: https://github.com/omidvarnia/Automatic_focal_spike_detection.HighlightsAutomatic spike detection increases the number of detected uniform epileptic interictal discharges and enhances statistical power of EEG-rsfMRI inter-subject variability maps,Automatic spike detection can identify additional activated brain regions with presumed epileptogenic focus not seen in standard analysis based on human markup,Automatic spike detection can shorten the IED identification process.

Objective The dominant model of cognitive impairment in focal epilepsy has emphasised structural bases for cognitive deficits. Current theories of cognition in the healthy brain emphasise the importance of the reweighting of brain network interactions in support of task performance. Here, we explore the hypothesis that cognitive deficits in epilepsy arise through abnormalities of dynamic functional network interactions. Method We studied 19 healthy controls and 37 temporal lobe epilepsy (TLE) patients, using a behavioural measure of verbal fluency (the Controlled Oral Word Association Test) and an fMRI verbal fluency paradigm (Orthographic Lexical Retrieval). Results Behaviourally, verbal fluency was significantly impaired in TLE. Psychophysiological interaction analyses of the fMRI data, which capture state-dependent changes in network connectivity, revealed reduced task-dependent modulations of connectivity from left superior medial frontal cortex to left middle frontal gyrus in TLE patients. Individual differences in verbal fluency among TLE cases was correlated with task-dependent changes in connectivity from left posterior cingulate to left superior medial frontal cortex, and from left superior medial frontal cortex to a range of right predominant brain areas. Interpretation These data reveal that the typical pattern of task-driven shifts in network connectivity is not observed in TLE. Our observations go beyond simple structure-function associations and suggest that failure of network flexibility can be an important contributor to cognitive impairment in epilepsy.

ObjectiveTo map functional MRI (fMRI) connectivity within and between the somatosensory cortex, putamen, and ventral thalamus in individuals from a family with a GABAergic deficit segregating with febrile seizures and genetic generalized epilepsy.MethodsWe studied 5 adults from a family with early-onset absence epilepsy and/or febrile seizures and a GABAA receptor subunit gamma2 pathogenic variant (GABRG2[R43Q]) vs 5 age-matched controls. We infer differences between participants with the GABRG2 pathogenic variant and controls in resting-state fMRI connectivity within and between the somatosensory cortex, putamen, and ventral thalamus.ResultsWe observed increased fMRI connectivity within the somatosensory cortex and between the putamen and ventral thalamus in all individuals with the GABRG2 pathogenic variant compared with controls. Post hoc analysis showed less pronounced changes in fMRI connectivity within and between the primary visual cortex and precuneus.ConclusionsAlthough our sample size was small, this preliminary study suggests that individuals with a GABRG2 pathogenic variant, raising risk of febrile seizures and generalized epilepsy, display underlying increased functional connectivity both within the somatosensory cortex and in striatothalamic networks. This human network model aligns with rodent research and should be further validated in larger cohorts, including other individuals with generalized epilepsy with and without known GABA pathogenic variants.

Glucocorticoids (GCs) are very effective at preventing carcinogen- and tumor promoter-induced skin inflammation, hyperplasia, and mouse skin tumor formation. The effects of GCs are mediated by a well-known transcription factor, the glucocorticoid receptor (GR). GR acts via two different mechanisms: transcriptional regulation that requires DNA-binding (transactivation) and DNA binding-independent protein-protein interactions between GR and other transcription factors, such as nuclear factor kappa B (NF-κB) or activator protein 1 (AP-1; transrepression). We hypothesize that the transrepression activities of the GR are sufficient to suppress skin tumor promotion. We obtained two GCs (RU24858 and RU24782) that have dissociated downstream effects and induce only transrepression activities of the GR in a number of systems. These compounds bind the GR with high affinity and repress AP-1 and NF-κB activities while showing a lack of GR transactivation. RU24858, RU24782, or control full GCs desoximetasone (DES) and fluocinolone acetonide (FA) were applied to the dorsal skin of SENCAR mice prior to application of the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA), two times per week for 2 weeks. DES, FA and RU24858 reversed TPA-induced epidermal hyperplasia and proliferation, while RU24782 treatment had no effect on these markers of skin tumor promotion. All tested compounds decreased TPA-induced c-jun mRNA levels in skin. DES, FA, and RU24858, but not RU24782, were also able to reverse TPA-induced increases in the mRNA levels of COX-2 and iNOS. These findings show that RU24858 but not RU24782 reduced TPA-induced epidermal hyperplasia, proliferation, and inflammation, while both compounds reversed c-jun mRNA increases in the skin.

The purpose of our study was to determine the effect of the combined action of phytochemicals on the early stages of skin tumorigenesis, i.e. initiation and promotion. We tested calcium D-glucarate (CG) given in the diet, while resveratrol (RES) and ursolic acid (UA) were applied topically. The 7,12-dimethylbenz[a]anthracene (DMBA)-initiated, 12-O-tetradecanoylphorbol-13-acetate (TPA)-promoted multistage skin carcinogenesis model in SENCAR mice was used. Mice received one topical dose of DMBA, then after one month, two weekly doses of TPA for 14 weeks until sacrifice. RES or UA were applied 20 min prior to DMBA or TPA treatment and 2% dietary CG was given from 2 weeks prior to 2 weeks after the DMBA dose or continually beginning 2 weeks prior to the first dose of TPA. UA applied alone and in combination with CG during the promotion stage was the only inhibitor of tumor multiplicity and tumor incidence. A number of combinations reduced epidermal proliferation, but only UA and the combination UA+CG applied during promotion significantly reduced epidermal hyperplasia. DMBA/TPA application resulted in significant increases in c-jun and p50, which were reversed by a number of different treatments. DMBA/TPA treatment also strongly increased mRNA levels of inflammation markers COX-2 and IL-6. All anti-promotion treatments caused a marked decrease in COX-2 and IL-6 expression compared to the DMBA/TPA control. These results show that UA is a potent inhibitor of skin tumor promotion and inflammatory signaling and it may be useful in the prevention of skin cancer and other epithelial cancers in humans.

Sturge-Weber syndrome is a rare, sporadic, neurocutaneous disorder classically characterized by a facial nevus in the trigeminal distribution (port wine stain), leptomeningeal angiomatosis, and glaucoma, although intracranial changes can be present without cutaneous involvement.1 Seizures occur in up to 75% of individuals, are often associated with headache, and stroke-like episodes causing prolonged neurologic deficits are also described.1,2

The purpose of our study was to determine the inhibitory effect of combined phytochemicals on chemically induced murine skin tumorigenesis. Our hypothesis was that concurrent topical and dietary treatment with selected compounds would lead to more efficient prevention of skin cancer. We tested ellagic acid and calcium D-glucarate as components of diets, while resveratrol was applied topically; grape seed extract was applied topically or in the diet. The 4-week inflammatory-hyperplasia assay based on the 7,12-dimethylbenz[a]anthracene (DMBA)–induced skin carcinogenesis model in SENCAR mice was used. We have found that all the selected combinations caused a marked decrease of epidermal thickness compared with the DMBA-treated group and also with groups treated with a single compound and DMBA. All combinations of resveratrol with other compounds showed a synergistic effect on hyperplasia and Ha-ras mutations. Skin tissue of mice receiving the combinations showed decreased cell proliferation and Bcl2 expression; decreased p21, a regulator of cell cycle; and decreased marker of inflammation cyclooxygenase-2. All the selected combinations diminished the DMBA-induced mRNA expression of the CYP1B1 level, and also caused a marked decrease of proto-oncogenes c-jun and c-fos, components of transcription factor activator protein. In conclusion, all combinations showed either additive or synergistic effects and their joint actions allowed for decreasing the doses of the compounds. Especially, resveratrol combinations with ellagic acid, grape seed extract, and other phytochemicals are very potent inhibitors of skin tumorgenesis, based on the suppression of epidermal hyperplasia as well as on the modulation of intermediate biomarkers of cell proliferation, cell survival, inflammation, oncogene mutation, and apoptosis. Cancer Prev Res; 3(2); 170–8

The purpose of our study was to determine the effect of combined action of phytochemicals on early stages of skin tumorgenesis, i.e., initiation and promotion. We tested calcium D-glucarate (CG) given in the diet, while resveratrol (RES) and ursolic acid (URA) were applied topically. The 7,12-dimethylbenz[a]anthracene (DMBA)-initiated, 12-O-tetradecanoylphorbol-13-acetate (TPA)-promoted multistage skin carcinogenesis model in SENCAR mice was used. Mice (6-7 weeks old) with shaved backs received one topical dose of DMBA (20 nmol), then after one month, two weekly doses (2 µg each) of TPA (tumor promoter) for 14 weeks until sacrifice. The phytochemicals RES (2.5 μmol) or URA (1 μmol) were applied topically 20 min prior to DMBA or TPA treatment and 2% dietary CG was given in the AIN-93G diet from 2 weeks prior to 2 weeks after the DMBA dose or continually beginning 2 weeks prior to the first dose of TPA. We determined the tumor incidence (% of mice with tumors) and tumor multiplicity (number of tumors per mouse) and using RT-PCR and immunochistochemical analyses, we checked the expression of some cell proliferation and inflammation related genes. URA applied alone and in combination with CG during the promotion stage was a strong inhibitor of tumor multiplicity and tumor incidence. Combinations of URA with dietary CG appeared to show some synergistic effects. All compounds and their combinations reduced epidermal proliferation, but only URA and a combination CG/URA applied during promotion significantly reduced hyperplasia, as determined by epidermal thickness measurements taken at 14 weeks of TPA treatment. DMBA/TPA treatments resulted in epidermal hyperplasia, characterized by significant increase in transcription factor AP-1 components and nuclear factor kappa B (NFkB) expression levels with a simultaneously increased expression of the inflammation markers COX-2 and IL-6, compared to untreated controls. All anti-promotion treatments (either single compounds or their combinations) caused a marked decrease of inflammation related genes levels compared to the DMBA/TPA control. On the other hand, only URA and URA with dietary CG diminished the induced expression of proto-oncogenes c-jun and c-fos (components of AP-1) and the expression of NFkB protein p50. These results show that URA is a potent inhibitor of skin tumor promotion and it may be useful in the prevention of skin cancer and other epithelial cancers in humans. Supported by NIH grants CA 102747 and P30 CA 54174-16S1. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3470.

Glucocorticoids are very effective in preventing carcinogen- and tumor promoter-induced skin inflammation, hyperplasia, and mouse skin tumor formation when applied to skin together with a carcinogen. Their control of cellular functions is mediated by a well-known transcription factor, glucocorticoid receptor (GR). GR acts via two different mechanisms: transcriptional regulation that requires DNA-binding and protein-protein interaction between GR and other transcription factors, such as nuclear factor kappa B (NF-κB) or activator protein 1 (AP-1), which is independent of DNA binding. We hypothesize that only the transrepression activities of the GR are sufficient to suppress skin tumor development. To test our hypothesis, we have synthesized two glucocorticoids (RU24858 and RU24782) that induce only transrepression activities of the GR. These two compounds are able to bind to the GR with high affinity and repress the AP-1 and NF-κB activity while showing reduced transactivation activities in vitro. Different doses (0.001, 0.01 and 0.1 mg) of RU24858, RU24782, desoxymethasone (DES) and fluocinolone acetonide (FA) or acetone were applied to the dorsal skin of female SENCAR mice 20 min. prior to TPA application (2 μg), two times per week for two weeks. Keratinocytes proliferation rates were estimated by measuring epidermis thickness and BrdU incorporation index. Immunohistochemistry and RT-PCR techniques were also used to evaluate expression level of genes involved in inflammation and cell cycle regulation. All studied compounds did not influence keratinocytes proliferation when applied alone. Application of DES, FA and RU24858 reversed TPA induced hyperplasia, in dose-depended manner, while RU24782 treatment had no effect on epidermis thickness or the BrdU incorporation index in TPA treated skins. All tested compounds were able to decrease c-jun mRNA level both in acetone and TPA-treated skins. DES, FA and RU24858 were also able to decrease elevated by TPA mRNA level of IL-6, COX-2 and iNOS. RU24782 did not influence mRNAs levels of these genes. These findings suggest that RU24782 had no effect on TPA-induced inflammation and hyperplasia in SENCAR mice, while RU24858 was able to reduce all tested inflammation markers, having only slight effect on epidermal hyperplasia. Supported by NIH grants CA 0796065-06 and P30 CA 54174-16S1. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2477.