Because the tripeptide MIF-1 (Pro-Leu-Gly-NH2) is known to attenuate the effects of neuroleptic-induced catalepsy as well as neuroleptic-induced proliferation of dopamine (DA) receptors, we studied the related naturally occurring peptide, Tyr-MIF-1 (Tyr-Pro-Leu-Gly-NH2) for similar properties. Male rats were treated SC for 11 consecutive days with either the DA D1 receptor antagonist SCH 23390 HC1 (0.50 mg/kg per day), the DA D2 receptor antagonist spiperone HCl (0.30 mg/kg per day), or vehicle. Half the rats were cotreated daily with Tyr-MIF-1 (1.0 mg/kg per day). The cataleptic effects of SCH 23390 were not altered by Tyr-MIF-1. Tolerance to SCH 23390-induced catalepsy did not develop during the 11-day treatment, and Tyr-MIF-1 had no effect on SCH 23390-induced catalepsy. However, tolerance developed to spiperone-induced catalepsy, and Tyr-MIF-1 attenuated this development of tolerance (p < 0.001). Locomotor and stereotyped activities of the DA D1 and D2 agonists, SKF 39393 (3.0 mg/kg) and quinpirole (3.0 mg/kg) were not affected by Tyr-MIF-1 after treatment with the DA antagonists was discontinued. Tyr-MIF-1 did not alter the Bmax or Kd for in vitro binding of [3H]SCH 23390 and [3H]spiperone to homogenates of the striatum. These findings indicate that Tyr-MIF-1 is able to selectively affect the development of receptor tolerance to a DA D2 receptor antagonist, and that this effect is unrelated to changes in affinity or numbers of D2 receptors.

Le sepsis est l'une des principales causes de mortalité en Amérique du nord (taux de mortalité : 30 à 60%). Les patients en sepsis qui décèdent sont souvent en"insuffisance surrénalienne relative", caractérisée par leur incapacité de produire suffisamment de glucocorticoïdes (GC) après stimulation à l'ACTH et une dysfonction de l'axe hypothalamo-hypophyso-surrénalien (HHS). La sécrétion de GC est contrôlée par l'hormone adrénocorticotrope (ACTH), la vasopressine (AVP) et des cytokines comme le Macrophage Migration Inhibitory Factor (MIF), un puissant agent pro-inflammatoire. MIF inhibe les effets du cortisol et de l'AVP. Hypothèses : MIF est impliqué dans l'incapacité de la glande surrénale à répondre adéquatement au stress induit par le sepsis. Son action s'exerce au niveau hypophysaire, altérant la sécrétion d'ACTH ou directement au niveau de la glande surrénale, interférant avec l'action de l'ACTH et de l'AVP. Méthodes : Modèle de rat soumis à un sepsis subaigu endotoxinique (10 mg/kg de LPS 055: B5 E.coli, 18 « 2 hs, avec ou sans coinfusion d'anti-MIF) et cultures primaires de cellules corticosurrénaliennes. Résultats : Validation du modèle animal. Les signes cliniques, l'hypertrophie des glandes surrénales accompagnée de modifications de la structure cellulaire et tissulaire, l'augmentation des taux plasmatiques d'ACTH et de corticostérone, la dissociation ACTH/corticostérone et l'augmentation d'AVP valident le modèle. Impact du traitement anti-MIF. Bien qu'aucune amélioration clinique n'ait été observée, le traitement avec de l'anti-MIF restaure une structure des glandes surrénales proche de la normale chez les animaux en sepsis subaigu. Ceci confirme de façon indirecte que, dans ce contexte, le MIF contribue à modifier la structure de ces glandes avec des impacts fonctionnels potentiels. Validation du modèle cellulaire.Le traitement à l'ACTH (10[indice supérieur -8]M) des cellules fasciculées induit une augmentation de corticostérone et le LPS induit une hypertrophie des cellules. Présence de MIF et CD74. In vivo, les immunobuvardages confirment la présence de MIF et CD74 dans l'hypophyse et les glandes surrénales avec une diminution d'expression de MIF hypophysaire opposée à une augmentation au niveau surrénalien lors du sepsis. In vitro, l'immunofluorescence confirme la présence de MIF et CD74 dans les cellules fasciculées, avec une colocalisation après traitement au LPS (0.1 mg/ml). MIF active la voie de p42/44[indice supérieur mapk] confirmant la présence de son récepteur CD74, son co-récepteur CD44 dans la glande surrénale et leur fonctionnalité. Conclusion : Nos modèles valident l'implication de MIF dans la régulation de l'axe hypothalamo-hypophyso-surrénalien et sa fonction surrénalienne.

Her2-positiver Brustkrebs, der Subtyp des Mammakarzinoms, bei dem eine Überexpression des epidermalen Wachstumsfaktor-Rezeptors-2 (ErbB2/Her2) vorliegt, hat für die betroffenen Frauen eine besonders schlechte Prognose. Eine positive Korrelation zwischen der ErbB2-Expression in Brusttumoren und der Expression des Makrophagen-Migration-inhibierenden Faktors (MIF), einem inzwischen gut bekannten tumorfördernden Protein, konnte bereits gezeigt werden. Ferner konnte gezeigt werden, dass MIF durch das Hitzeschockprotein 90 (Hsp90) in einem Mausmodell des Her2-positiven Brustkrebses stabilisiert wird. Der zugrundeliegende Mechanismus war bisher unverstanden. In dieser Doktorarbeit konnte erstmalig demonstriert werden, dass Hitzeschockfaktor-1 (HSF-1), der Transkriptionsfaktor der stressinduzierten Hitzeschockproteine (HSP), einschließlich Hsp90, in ErbB2-überexprimierenden SK-BR-3-Brustkrebszellen konstitutiv durch ErbB2 aktiviert wird. Durch eine Behandlung mit dem ErbB2-Inhibitor CP724.714 konnte die aktivierende Serin326-Phosphorylierung von HSF-1 verhindert werden. Als Folge wird, wie durch Western-Blot-Analysen gezeigt, die HSP-Maschinerie inhibiert und tumorfördernde Hsp90-Klienten wie MIF, Akt, mutiertes p53, ErbB2 und HSF-1 destabilisiert. Außerdem konnte die unterbleibende HSF-1-Aktivierung durch quantitative PCR-Analysen und Immunfluoreszenzmikroskopie bestätigt werden. Die mechanistischen Untersuchungen konnten die hier erstmalig beschriebene ErbB2-Akt-HSF-1-Achse aufdecken, über die HSF-1 in SK-BR-3-Zellen reguliert wird. Ferner konnte eine ErbB2-Inhibition sogar die HSF-1-Aktivierung durch einen Hitzeschock unterbinden. Unsere Ergebnisse zeigen zum ersten Mal, dass die ErbB-2-Überexpression in SK-BR-3-Zellen eine konstitutive HSF-1-Aktivierung bewirkt, mit der Folge, dass tumorfördernde Hsp90-Klienten wie MIF, HSF-1 selbst, ErbB2 und mutiertes p53 stabilisiert werden. Die neu entdeckte ErbB2-Akt-HSF-1-Hsp90-Klienten-Achse legt möglicherweise neue Angriffspunkte für zusätzliche Pharmaka bei der Therapie Her2-positiven Brustkrebses offen.

Submitted by Pós Imunologia (ppgimicsufba@gmail.com) on 2017-02-14T15:24:05Z No. of bitstreams: 1 DISSERTAÇÃO - Samara Alves Sá Teles.pdf: 1106383 bytes, checksum: 1bb15f702feb2f073001225aaae2d132 (MD5) / Approved for entry into archive by Delba Rosa (delba@ufba.br) on 2017-06-29T13:56:29Z (GMT) No. of bitstreams: 1 DISSERTAÇÃO - Samara Alves Sá Teles.pdf: 1106383 bytes, checksum: 1bb15f702feb2f073001225aaae2d132 (MD5) / Made available in DSpace on 2017-06-29T13:56:29Z (GMT). No. of bitstreams: 1 DISSERTAÇÃO - Samara Alves Sá Teles.pdf: 1106383 bytes, checksum: 1bb15f702feb2f073001225aaae2d132 (MD5) / CAPES / Com o aumento da prevalência de doenças inflamatórias, em especial as alérgicas, a busca por estratégias terapêuticas visando à melhoria de vida dos indivíduos doentes tornou-se um vasto campo de pesquisa. Neste âmbito, o uso de helmintos e derivados que possuem potencial imunomodulatório tem se mostrado eficiente na inibição da inflamação em modelos experimentais dessas doenças. Objetivo: Produzir e analisar, in silico, o antígeno recombinante do Trichuris trichiura homólogo ao fator inibidor de migração de macrófagos (rTt-MIF) e avaliar seu efeito em cultura de células monomorfonucleares de sangue periférico (CMSP) de indivíduos atópicos e não atópicos. Métodos: A análise in silico da proteína foi realizada utilizando diversas ferramentas de bioinformática. A sequência codificadora do antígeno recombinante foi sintetizada e clonada em um plasmídeo de expressão, a partir do qual foi realizada a expressão heteróloga da proteína em sistema procarioto, com posterior purificação por cromatografia de afinidade e determinação do conteúdo proteico e de endotoxina. Após teste cutâneo e dosagem de IgE por ImunoCAP, foram selecionados 12 indivíduos não atópicos e 14 indivíduos atópicos cujo sangue periférico foi coletado para realizar o cultivo de células monomorfonucleares. As células foram cultivadas sob três condições: estímulo do rTt-MIF, meio de cultivo sem estímulo e estimuladas por Pokeweed ou LPS. Após o cultivo, os sobrenadantes foram coletados para realização da dosagem das citocinas IL-10, IFN-γ, IL-5 e IL-17A. Resultados: A molécula caracterizada como estável e solúvel foi produzida, obtida na quantidade de 2,4 mg/mL com 1,9 EU/mL. O rTt-MIF induziu o aumento da produção de IL-10 pelas células dos indivíduos atópicos (P=0,0001) e dos não atópicos (P=0,0005). Em relação às citocinas IFN-γ, IL-5 e IL-17, o rTt-MIF não induziu a produção destas pelas células dos indivíduos atópicos e não atópicos. Conclusão: A ação do rTt-MIF sobre o cultivo de células momonucleares do sangue periférico, de aumentar a produção de IL-10 e não induzir a produção de IFN-γ, IL-5 e IL-17A, mostra o potencial imunomodulador dessa molécula, com possível efeito de reduzir a elevação de eosinófilos, neutrófilos e citocinas inflamatórias. / With the increasing prevalence of inflammatory diseases, in particular allergies, the search for therapeutic strategies aiming to improve life quality of sick individuals has become a vast field of research. In this context, the use of helminths and their derivatives that demonstrate potential immunomodulatory effect has been effective in inhibiting inflammation in experimental models of inflammatory diseases. Objective: To produce and analyze in silico the recombinant antigen from Trichuris trichiura homologous to the macrophage migration inhibitory factor (rTt-MIF) and evaluate its effect on peripheral blood mononuclear cells culture (PBMC) of atopic and non-atopic individuals. Methods: Bioinformatics tools made the analysis in silico. The Tt-MIF codifying sequence was synthesized and cloned into a plasmid, allowing the heterologous expression of the protein in a prokaryotic system, with subsequent purification by affinity chromatography and protein and endotoxin quantifications. After prick test and IgE dosage by ImmunoCAP test, 12 non-atopic individuals and 14 atopic individuals were selected, whose peripheral blood were collected to obtain the mononuclear cells (PBMC) for in vitro culture. Cells were stimulated with the rTt-MIF, as negative control cells were cultivated without stimuli and, as positive control, cells were cultivated with Pokeweed or LPS. After the culture, the supernatants were assayed to quantify IL-10, IFN-γ, IL-5 and IL-17A. Results: The protein characterized as soluble and stable was produced and obtained in the amount of 2,4 mg/mL with 1,9 EU/mL. The rTt-MIF induced a stimulatory effect on IL-10 production by cells from atopic individuals (P=0.0001) and by cells from non-atopic individuals (P=0,0005). The rTt-MIF did not induce the production of IFN-γ, IL-5 and IL-17A by cells from atopic and non-atopic individuals. Conclusion: The effects of rTt-MIF increasing IL-10 production and not inducing the production of IFN-γ, IL-5 and IL-17A on human PBMC cultures are indicative of its immunomodulatory potential, with possible effect of decreasing eosinophilic and neutrophilic presence and inducing immune regulation.

E-rosette formation by human lymphocytes incubated with sheep red blood cells (sRBC) is inhibited by morphine. We studied the ability of the opiate antagonists naloxone and Tyr-MIF-1 (Tyr-Pro-Leu-Gly-NH2) to block this action. Active E-rosette formation by lymphocytes incubated with morphine was reduced from the control of 35.7±1.7% to 23.7±1.5% (p<0.001). Similarly, total E-rosette formation was reduced by morphine from the control of 65.8±1.3% to 53.2±2.9% (p<0.001). These effects were blocked by co-incubation of the lymphocytes with either Tyr-MIF-1 or naloxone (p<0.05). Tyr-MIF-1 was active (p<0.05) at concentrations as dilute as 10-13M. These results indicate that the neuropeptide Tyr-MIF-1 exerts an antiopiate effect at the human T-lymphocyte.

In an attempt to determine the mechanism by which the tripeptide l-prolyl-l-leucyl-glycine amide (PLG, MIF-I) exerts its antiparkinsonian effect, the action of this substance on various postsynaptic components of striatal dopaminergic nerves was studied. It was shown that injection of rats with MIF-I (1 mg/kg, IP×5, 24 hr intervals) did not alter tyrosine hydroxylase, dopa decarboxylase, choline acetyltransferase and glutamic acid decarboxylase activities in the striatum under the conditions tested. The activities of adenylate cyclase, dopamine-stimulated adenylate cyclase, and guanylate cyclase were not altered in vitro by various concentrations of MIF-I (0.1 to 1000 μM), although VIP and neurotensin had some effect. Also the rate of uptake of 3H-dopamine by rat striatal synaptosomes was unchanged, as was the binding of 3H-dopamine and 3H-spiperone to beef caudate membranes. This series of studies indicates that MIF-I does not act directly on the striatal dopamine postsynaptic receptor under the conditions tested, although it is possible that MIF-I could act indirectly at this or another site in vivo by releasing or activating some other factor.

Development of tyrosine kinase inhibitors (TKIs) against oncogenic drivers has significantly improved survival of patients with oncogene-mutated non-small cell lung cancer (NSCLC). However, acquired resistance to TKIs emerges over time in essentially all patients who initially respond. Recent evidence suggests that drug-tolerant persister (DTP) cells, which survive and adapt to targeted therapies during an early phase of treatment, play an important role in the emergence of drug resistance. A previous study reported that cluster of differentiation 74 (CD74) expression is upregulated in epidermal growth factor receptor (EGFR)-mutated lung cancer after treatment with EGFR-TKIs and that CD74 can be one of the DTP cell markers. However, both the mechanism underlying CD74 expression and the role of CD74 in DTP cells remain unclear. In the current study, an attempt was made to identify the mechanism using cell culture systems and transgenic mouse models. The results confirmed CD74 upregulation at the messenger RNA (mRNA) level after treatments with TKIs in various oncogene-mutated cell lines, including those with EGFR mutations, ROS1 fusions, and ALK fusions. The class II transactivator (CIITA), upstream of CD74, and tumor necrosis factor (TNF)-α expression were induced by treatments with TKIs in tumor cells, leading to an increase in CD74 expression. In addition, the results showed that treatments with TKIs enhance the autocrine secretion of macrophage migration inhibitory factor (MIF), a ligand of CD74, from tumor cells. This implied that autocrine stimulation of CD74 signaling blocks apoptosis and causes emergence of DTP cells. To examine whether CD74 plays an important role in the emergence of resistance to TKIs in vivo, experiments were completed in which lung-specific EGFR-L858R-T790M transgenic mice were crossed with Cd74 knockout mice. The results showed that complete deletion of CD74 overcomes or delays resistance to TKIs. Taken together, the results of this study suggest that the MIF-CD74 axis can be a novel target to overcome resistance in driver-mutated NSCLC. / 2026-02-28T00:00:00Z

L’hypertension pulmonaire (HP) est définie par une élévation de la pression artérielle pulmonaire moyenne (PAPm) au-delà de 25 mm de mercure (Hg) au repos en raison de l’augmentation progressive et soutenue des résistances vasculaires pulmonaires, menant à l'insuffisance cardiaque droite. La dysfonction endothéliale pulmonaire associée à l'HTAP est maintenant considérée comme un mécanisme pathogénique clé qui pourrait être préjudiciable à la fois pour la susceptibilité et le développement du remodelage vasculaire pulmonaire. Au niveau des cellules endothéliales (CE), la fixation du facteur inhibiteur de la migration des macrophages (MIF), un des plus anciens médiateurs immunologiques connus, sur le CD74 va initier une cascade de signalisation intracellulaire clef pour la prolifération, la survie cellulaire et la production de différents facteurs inflammatoires. C’est pourquoi, ces travaux de doctorat ont visés à : 1) Etudier l’importance de la voie MIF/CD74 dans l'acquisition/maintien d’un phénotype pro-inflammatoire des CE pulmonaires dans l'HTAP ; 2) Tester l’efficacité de nouveaux antagonistes de MIF, synthétisés et brevetés par la société MIFCARE, contre ce phénotype endothélial et le développement d’HP expérimentales.Nos données mettent en lumière le rôle critique de la voie MIF/CD74 pour le phénotype aberrant des CE pulmonaires HTAP et soulignent son importance comme nouvelle cible thérapeutique prometteuse pour lutter contre le remodelage vasculaire pulmonaire. Cette meilleure compréhension du rôle de la voie MIF/CD74 dans le phénotype endothélial aberrant, nous a permis l’identification d’une nouvelle molécule à forte affinité, administrable par voie orale, capable de ralentir la progression d’HP expérimentales (brevet européen en soumission). Cependant, des études plus poussées, en cours de réalisation, sont encore nécessaires avant de pouvoir transférer ces connaissances vers une utilisation clinique de ces nouveaux candidats « médicaments ». / Pulmonary arterial hypertension (PAH) is a severe progressive cardiopulmonary disorder characterized by vascular proliferation and remodeling of the small pulmonary arteries. These can lead to a progressive increase in pulmonary vascular resistance and ultimately to right ventricular failure and death. Pulmonary endothelial dysfunction and pro-inflammatory phenotype associated with PAH are now considered as a key pathogenic mechanism that could be detrimental to both the susceptibility and development of the pulmonary vascular remodeling.In pulmonary endothelial cells (EC), the binding of the immune mediator MIF (Macrophage Migration Inhibitory Factor), to its receptor CD74 initiates an intracellular signaling cascade leading to cell proliferation, cell survival and the secretion of various inflammatory mediators. Therefore, the present work seeks to: (1) Determine the importance of the MIF/CD74 signaling pathway in the acquisition of an abnormal pro-inflammatory EC phenotype in PAH; (2) Test the efficacies of MIF inhibitors, synthesized and patented by MIFCARE, on this abnormal pro-inflammatory EC phenotype and on the development of experimental pulmonary hypertension (PH).Our data highlight the critical role of the MIF/CD74 axis in the endothelial dysfunction and pro-inflammatory phenotype of pulmonary EC in PAH. In addition, our data emphasize its importance as a promising new therapeutic target to prevent the pulmonary vascular remodeling associated to this disorder. Furthermore, we were successful in identifying an agent from a novel class of MIF antagonists optimized for in vivo use that have the ability to partially reverse established PH in rats and to partially inhibit the pro-inflammatory EC phenotype observed in PAH.Collectively, we demonstrated the importance of the MIF/CD74 axis and that its inhibition with MIF antagonist agents could represent a promising strategy for the treatment of PAH (under patent). However, further studies are still needed before transferring this knowledge to clinical use of these new candidates.

O processo da carcinogênese é provocado por múltiplos estágios, envolvendo desordens potencialmente malignas, iniciação, invasão, progressão e metástase. O prognóstico do carcinoma epidermoide de boca (CEB) ainda permanece desfavorável devido ao diagnóstico tardio. Para mitigar esta complicação, biomarcadores tem sido utilizados para ajudar no diagnóstico precoce e entender melhor a influência sobre a carcinogênese oral, onde vias de sinalização são ativadas, principalmente a PI3K/AKT. MIF foi relacionada a progressão de diversos tipos cânceres, porém pouco se sabe seu papel na evolução do CEB. Por isso, o objetivo deste estudo foi identificar e caracterizar através do padrão de expressão imuno-histoquímico proteínas participantes da via de sinalização de PI3K/AKT: AKT1 e PAKT e sua associação com a expressão de MIF em fragmento de mucosa, hiperqueratose sem e com displasia e CEB correlacionando com a progressão da doença e características clinico-demográficos. Foram utilizados 73 blocos de parafina, avaliados quanto à porcentagem da expressão de cada marcador e coletados os dados clínicos epidemiológicos referentes para correlaciona-los à imunomarcação. A imunonopositividade ocorreu nos casos de mucosa normal, sem e com displasia e CEB. Nos casos de mucosa normal foram positivos para PAKT (50%), AKT (60%), MIF (80%). Em sem displasia, foi observado imunomarcação para PAKT (50%) e MIF (50%). Com displasia houve marcação PAKT (81,81%) e MIF (81%). Nos espécimes de CEB ocorreu em PAKT(100%), AKT (95,23%) e MIF (90,5%). Todos os anticorpos tiveram alta expressão no CEB em comparação com a mucosa normal (p<0,0001), sem displasia (p<0,0001) e com displasia (p<0,0001). Observou-se também influência sobre o fator de risco como tabagismo, etilismo e etnia, respectivamente para os grupos sem displasia, CEB e com displasia. Assim, estas proteínas podem ser consideradas potenciais marcadores preditores do CEB. / The carcinogenesis process is caused by multiple stages, involving potentially malignant disorders, initiation, invasion, progression and metastasis. The prognosis of squamous cell carcinoma (CEB) remains unfavorable due to late diagnosis. To mitigate this complication, biomarkers have been used to aid in early diagnosis and better understand the influence on oral carcinogenesis, which are activated signaling pathways, particularly PI3K / AKT. MIF was related to progression of many types cancers, but its role in the evolution of CEB is little known. Therefore, the aim of this study was to identify and characterize by the expression pattern of immunohistochemical participants proteins signaling pathway PI3K / AKT: AKT1 and PAKT and its association with MIF expression in normal mucosa, hyperkeratosis with and without dysplasia and CEB correlating with the progression of the disease and clinical and demographic characteristics. 73 paraffin blocks were used, in which evaluated the percentage of expression of each marker and collected epidemiological clinical data to correlate them to immunostaining. The imunonopositividade occurred in cases of normal mucosa, hyperkeratosis with and without dysplasia. In cases of normal mucosa were positive for PAKT (50%), AKT (60%), MIF (80%). In no dysplasia, immunostaining was observed PAKT (50%) and MIF (50%). With dysplasia was marking PAKT (81.81%) and MIF (81%). In CEB specimens occurred in PAKT (100%), AKT (95.23%) and MIF (90.5%). All antibodies had high expression in the CEB compared to normal mucosa (p <0.0001) without dysplasia (p <0.0001), and dysplasia (p <0.0001). It was also observed influence on the risk factors such as smoking, alcohol consumption and the ethnicity, respectively, for with dysplasia groups, CEB and without dysplasia. Thus, these proteins can be considered potential early diagnostic markers of CEB.

O processo da carcinogênese é provocado por múltiplos estágios, envolvendo desordens potencialmente malignas, iniciação, invasão, progressão e metástase. O prognóstico do carcinoma epidermoide de boca (CEB) ainda permanece desfavorável devido ao diagnóstico tardio. Para mitigar esta complicação, biomarcadores tem sido utilizados para ajudar no diagnóstico precoce e entender melhor a influência sobre a carcinogênese oral, onde vias de sinalização são ativadas, principalmente a PI3K/AKT. MIF foi relacionada a progressão de diversos tipos cânceres, porém pouco se sabe seu papel na evolução do CEB. Por isso, o objetivo deste estudo foi identificar e caracterizar através do padrão de expressão imuno-histoquímico proteínas participantes da via de sinalização de PI3K/AKT: AKT1 e PAKT e sua associação com a expressão de MIF em fragmento de mucosa, hiperqueratose sem e com displasia e CEB correlacionando com a progressão da doença e características clinico-demográficos. Foram utilizados 73 blocos de parafina, avaliados quanto à porcentagem da expressão de cada marcador e coletados os dados clínicos epidemiológicos referentes para correlaciona-los à imunomarcação. A imunonopositividade ocorreu nos casos de mucosa normal, sem e com displasia e CEB. Nos casos de mucosa normal foram positivos para PAKT (50%), AKT (60%), MIF (80%). Em sem displasia, foi observado imunomarcação para PAKT (50%) e MIF (50%). Com displasia houve marcação PAKT (81,81%) e MIF (81%). Nos espécimes de CEB ocorreu em PAKT(100%), AKT (95,23%) e MIF (90,5%). Todos os anticorpos tiveram alta expressão no CEB em comparação com a mucosa normal (p<0,0001), sem displasia (p<0,0001) e com displasia (p<0,0001). Observou-se também influência sobre o fator de risco como tabagismo, etilismo e etnia, respectivamente para os grupos sem displasia, CEB e com displasia. Assim, estas proteínas podem ser consideradas potenciais marcadores preditores do CEB. / The carcinogenesis process is caused by multiple stages, involving potentially malignant disorders, initiation, invasion, progression and metastasis. The prognosis of squamous cell carcinoma (CEB) remains unfavorable due to late diagnosis. To mitigate this complication, biomarkers have been used to aid in early diagnosis and better understand the influence on oral carcinogenesis, which are activated signaling pathways, particularly PI3K / AKT. MIF was related to progression of many types cancers, but its role in the evolution of CEB is little known. Therefore, the aim of this study was to identify and characterize by the expression pattern of immunohistochemical participants proteins signaling pathway PI3K / AKT: AKT1 and PAKT and its association with MIF expression in normal mucosa, hyperkeratosis with and without dysplasia and CEB correlating with the progression of the disease and clinical and demographic characteristics. 73 paraffin blocks were used, in which evaluated the percentage of expression of each marker and collected epidemiological clinical data to correlate them to immunostaining. The imunonopositividade occurred in cases of normal mucosa, hyperkeratosis with and without dysplasia. In cases of normal mucosa were positive for PAKT (50%), AKT (60%), MIF (80%). In no dysplasia, immunostaining was observed PAKT (50%) and MIF (50%). With dysplasia was marking PAKT (81.81%) and MIF (81%). In CEB specimens occurred in PAKT (100%), AKT (95.23%) and MIF (90.5%). All antibodies had high expression in the CEB compared to normal mucosa (p <0.0001) without dysplasia (p <0.0001), and dysplasia (p <0.0001). It was also observed influence on the risk factors such as smoking, alcohol consumption and the ethnicity, respectively, for with dysplasia groups, CEB and without dysplasia. Thus, these proteins can be considered potential early diagnostic markers of CEB.