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1.
Domest Anim Endocrinol ; 88: 106839, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38433026

RESUMEN

The oviduct, the organ of the female reproductive system where fertilization and early embryonic development occur, provides an optimal environment for the final maturation of oocytes, storage, and sperm capacitation and transport of gametes and embryos. During the estrous cycle, the oviduct is affected by ovarian sex hormones, resulting in changes aimed at maintaining an appropriate microenvironment. Normal cell migration is tightly regulated, its role being essential for the development and maintenance of organ and tissue functions as well as for regeneration following injury. Due to their involvement in focal contact formations, focal adhesion kinase (PTK2) and paxillin (PXN) are key proteins in the study of cell migration and adhesion. The objective of this work was to compare the expression of PTK2 and PXN in oviductal cells along the estrous cycle and to determine if their expression is regulated by the presence of 17-ß estradiol (E2) and/or progesterone (P4). No transcripts of PTK2 or of PXN were detected in cells corresponding to the luteal phase. Additionally, hormonal stimulation experiments on bovine oviductal cell cultures (BOECs) were carried out, where P4 inhibited the expression of both genes. Migration assays demonstrated that P4 reduced BOECs migration capacity. P4 treatment also reduced cell adhesion, while E2 increased the number of adhered cells. In conclusion, the presence of E2 and P4 regulates the expression of genes involved in the formation of focal contacts and modifies the migration and adhesion of BOECs. Understanding the effect of steroid hormones on BOECs is critical to grasp the impact of steroid control on oviductal function and its contribution to establishing successful pregnancies.


Asunto(s)
Células Epiteliales , Estradiol , Trompas Uterinas , Adhesiones Focales , Progesterona , Animales , Femenino , Bovinos , Estradiol/farmacología , Progesterona/farmacología , Progesterona/metabolismo , Células Epiteliales/fisiología , Trompas Uterinas/fisiología , Trompas Uterinas/citología , Paxillin/metabolismo , Paxillin/genética , Movimiento Celular , Ciclo Estral/fisiología , Células Cultivadas , Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Regulación de la Expresión Génica , Oviductos/fisiología
2.
Biochem Biophys Res Commun ; 625: 188-195, 2022 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-35988459

RESUMEN

Hepatocellular carcinoma (HCC) has been a long-time public health problem impacting people's heath and challenging healthcare professions because of its poor prognosis and high lethality. More and more evidence indicated the important role of long non-coding RNAs (lncRNAs) in carcinogenesis and cancer metabolism in a variety of cancer types. In this study, we found that FIRRE, a recently identified cancer-associated lncRNA located on chromosome X, is highly expressed in HCC cell lines and tissue samples, and its expression is positively correlated with poor HCC prognosis. In vitro and in vivo functional analyses showed that FIRRE could promote the proliferation, migration, and invasion of HCC. As for the potential mechanism, FIRRE specifically binds to the splicing factor MBNL3 to affect the expression of PXN to regulate the pathological characteristics of HCC cells. In summary, our study showed that the lncRNA FIRRE is a cancer promoting factor and may be a potential biomarker for the prognosis and drug target for the treatment of HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , ARN Largo no Codificante , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/patología , Paxillin/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Regulación hacia Arriba
3.
J Cell Sci ; 134(20)2021 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-34553765

RESUMEN

Protein tyrosine phosphatase 1B (PTP1B, also known as PTPN1) is an established regulator of cell-matrix adhesion and motility. However, the nature of substrate targets at adhesion sites remains to be validated. Here, we used bimolecular fluorescence complementation assays, in combination with a substrate trapping mutant of PTP1B, to directly examine whether relevant phosphotyrosines on paxillin and focal adhesion kinase (FAK, also known as PTK2) are substrates of the phosphatase in the context of cell-matrix adhesion sites. We found that the formation of catalytic complexes at cell-matrix adhesions requires intact tyrosine residues Y31 and Y118 on paxillin, and the localization of FAK at adhesion sites. Additionally, we found that PTP1B specifically targets Y925 on the focal adhesion targeting (FAT) domain of FAK at adhesion sites. Electrostatic analysis indicated that dephosphorylation of this residue promotes the closed conformation of the FAT 4-helix bundle and its interaction with paxillin at adhesion sites.


Asunto(s)
Fosfoproteínas , Proteína Tirosina Fosfatasa no Receptora Tipo 1 , Uniones Célula-Matriz/metabolismo , Proteínas del Citoesqueleto/metabolismo , Quinasa 1 de Adhesión Focal/genética , Quinasa 1 de Adhesión Focal/metabolismo , Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Adhesiones Focales/metabolismo , Paxillin/genética , Paxillin/metabolismo , Fosfoproteínas/metabolismo , Fosforilación , Proteína Tirosina Fosfatasa no Receptora Tipo 1/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 1/metabolismo
4.
Front Endocrinol (Lausanne) ; 12: 640298, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33841333

RESUMEN

Glioblastomas are the most common and aggressive primary brain tumors in adults, and patients with glioblastoma have a median survival of 15 months. Some alternative therapies, such as Src family kinase inhibitors, have failed presumably because other signaling pathways compensate for their effects. In the last ten years, it has been proven that sex hormones such as progesterone (P4) can induce growth, migration, and invasion of glioblastoma cells through its intracellular progesterone receptor (PR), which is mostly known for its role as a transcription factor, but it can also induce non-genomic actions. These non-classic actions are, in part, a consequence of its interaction with cSrc, which plays a significant role in the progression of glioblastomas. We studied the relation between PR and cSrc, and its effects in human glioblastoma cells. Our results showed that P4 and R5020 (specific PR agonist) activated cSrc protein since both progestins increased the p-cSrc (Y416)/cSrc ratio in U251 and U87 human glioblastoma derived cell lines. When siRNA against the PR gene was used, the activation of cSrc by P4 was abolished. The co-immunoprecipitation assay showed that cSrc and PR interact in U251 cells. P4 treatment also promoted the increase in the p-Fak (Y397) (Y576/577)/Fak and the decrease in p-Paxillin (Y118)/Paxillin ratio, which are significant components of the focal adhesion complex and essential for migration and invasion processes. A siRNA against cSrc gene blocked the increase in the p-Fak (Y576/Y577)/Fak ratio and the migration induced by P4, but not the decrease in p-Paxillin (Y118)/Paxillin ratio. We analyzed the potential role of cSrc over PR phosphorylation in three databases, and one putative tyrosine residue in the amino acid 87 of PR was found. Our results showed that P4 induces the activation of cSrc protein through its PR. The latter and cSrc could interact in a bidirectional mode for regulating the activity of proteins involved in migration and invasion of glioblastomas.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Proteína Tirosina Quinasa CSK/metabolismo , Glioblastoma/metabolismo , Receptores de Progesterona/metabolismo , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular/efectos de los fármacos , Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Adhesiones Focales/metabolismo , Humanos , Invasividad Neoplásica , Paxillin/metabolismo , Fosforilación , Progesterona/metabolismo , Proteínas Tirosina Quinasas/metabolismo , ARN Interferente Pequeño/metabolismo , Transducción de Señal/efectos de los fármacos , Tirosina/química
5.
Biochim Biophys Acta Mol Basis Dis ; 1866(8): 165810, 2020 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-32339641

RESUMEN

The current standard of care for locally advanced rectal cancer (RC) is neoadjuvant radio-chemotherapy (NRC) with 5-fluorouracil (5Fu) as the main drug, followed by surgery and adjuvant chemotherapy. While a group of patients will achieve a pathological complete response, a significant percentage will not respond to the treatment. The Unfolding Protein Response (UPR) pathway is generally activated in tumors and results in resistance to radio-chemotherapy. We previously showed that RHBDD2 gene is overexpressed in the advanced stages of colorectal cancer (CRC) and that it could modulate the UPR pathway. Moreover, RHBDD2 expression is induced by 5Fu. In this study, we demonstrate that the overexpression of RHBDD2 in CACO2 cell line confers resistance to 5Fu, favors cell migration, adhesion and proliferation and has a profound impact on the expression of both, the UPR genes BiP, PERK and CHOP, and on the cell adhesion genes FAK and PXN. We also determined that RHBDD2 binds to BiP protein, the master UPR regulator. Finally, we confirmed that a high expression of RHBDD2 in RC tumors after NRC treatment is associated with the development of local or distant metastases. The collected evidence positions RHBDD2 as a promising prognostic biomarker to predict the response to neoadjuvant therapy in patients with RC.


Asunto(s)
Resistencia a Antineoplásicos/genética , Regulación Neoplásica de la Expresión Génica , Proteínas de la Membrana/genética , Neoplasias del Recto/terapia , Respuesta de Proteína Desplegada/efectos de los fármacos , Antimetabolitos Antineoplásicos/farmacología , Células CACO-2 , Adhesión Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Chaperón BiP del Retículo Endoplásmico , Fluorouracilo/farmacología , Quinasa 1 de Adhesión Focal/genética , Quinasa 1 de Adhesión Focal/metabolismo , Adhesiones Focales/efectos de los fármacos , Células HCT116 , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Metástasis Linfática , Proteínas de la Membrana/metabolismo , Terapia Neoadyuvante/métodos , Paxillin/genética , Paxillin/metabolismo , Unión Proteica , Neoplasias del Recto/genética , Neoplasias del Recto/metabolismo , Neoplasias del Recto/patología , Transducción de Señal , Factor de Transcripción CHOP/genética , Factor de Transcripción CHOP/metabolismo , eIF-2 Quinasa/genética , eIF-2 Quinasa/metabolismo
6.
Int. j. morphol ; 38(1): 165-175, Feb. 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1056416

RESUMEN

An alternative hyper-ovulator inducer to replace clomiphene citrate (CC) is needed as it is unsuitable for women with polycystic ovarian syndrome and is associated with low pregnancy rates. Anastrozole is an effective hyper-ovulator inducer, but has not been well researched. In order to determine the effectiveness of anastrozole as a hyper-ovulator inducer and to an extent compare it with CC in similar situations, this study ascertained the effects of these drugs on the expression of the focal adhesion proteins, paxillin and FAK, which are uterine receptivity markers in the surface luminal uterine epithelial cells of day 1 and day 6 pregnant Wistar rats. The results show that paxillin is localized in focal adhesions at the base of the uterine epithelial cells at day 1 of pregnancy whereas at day 6, paxillin disassembles from the basal focal adhesions and localizes and increases its expression apically. FAK is faintly expressed at the basal aspect of the uterine epithelial cells while moderately expressed at the cell-to-cell contact at day 1 in all groups from where it disassembles and relocates apically and becomes more intensely expressed at day 6 of pregnancy in untreated and anastrozole treated rats. Although paxillin is localized apically at day 6, its expression is significantly down-regulated with CC treatment suggesting its interference with the implantation process. These findings seem to suggest that anastrozole could favor implantation.


Para reemplazar el citrato de clomifeno (CC) es necesario un inductor de hiperovulación alternativo, ya que no es adecuado para mujeres con síndrome de ovario poliquístico y está asociado con tasas bajas de embarazo. El anastrozol es un inductor eficaz del hiper-ovulador, pero no se ha investigado adecuadamente. Con el fin de determinar la efectividad del anastrozol como inductor del hiper-ovulador y, en cierta medida, compararlo con CC en situaciones similares, este estudio determinó los efectos de estos fármacos en la expresión de las proteínas de adhesión focal, paxillin y FAK, uterinas marcadores de receptividad en la superficie luminal de células uterinas epiteliales, del día 1 y día 6 en ratas Wistar preñadas. Los resultados muestran que la paxilina se localiza en adherencias focales en la base de las células epiteliales uterinas en el día 1 del embarazo, mientras que en el día 6, la paxilina se desmonta de las adherencias focales basales y localiza y aumenta su expresión apicalmente. FAK se expresa débilmente en el aspecto basal de las células epiteliales uterinas, mientras que se expresa moderadamente en el contacto de célula a célula en el día 1 en todos los grupos, donde se separa y se reubica apicalmente y se expresa con mayor intensidad el día 6 de la preñez, en pacientes no tratados y tratados. ratas tratadas con anastrozol. Aunque la paxillina se localiza apicalmente en el día 6, su expresión está significativamente disminuida con el tratamiento con CC, lo que sugiere su interferencia con el proceso de implantación. Estos hallazgos sugieren que el anastrozol podría favorecer el proceso de implantación.


Asunto(s)
Animales , Femenino , Ratas , Útero/efectos de los fármacos , Anastrozol/farmacología , Ovulación/efectos de los fármacos , Ratas Wistar , Adhesiones Focales/efectos de los fármacos , Epitelio/efectos de los fármacos , Proteína-Tirosina Quinasas de Adhesión Focal/efectos de los fármacos , Paxillin/efectos de los fármacos , Reacción en Cadena en Tiempo Real de la Polimerasa , Microscopía Fluorescente
7.
Mem Inst Oswaldo Cruz ; 114: e180593, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31433004

RESUMEN

BACKGROUND: Cardiac physiology depends on coupling and electrical and mechanical coordination through the intercalated disc. Focal adhesions offer mechanical support and signal transduction events during heart contraction-relaxation processes. Talin links integrins to the actin cytoskeleton and serves as a scaffold for the recruitment of other proteins, such as paxillin in focal adhesion formation and regulation. Chagasic cardiomyopathy is caused by infection by Trypanosoma cruzi and is a debilitating condition comprising extensive fibrosis, inflammation, cardiac hypertrophy and electrical alterations that culminate in heart failure. OBJECTIVES: Since mechanotransduction coordinates heart function, we evaluated the underlying mechanism implicated in the mechanical changes, focusing especially in mechanosensitive proteins and related signalling pathways during infection of cardiac cells by T. cruzi. METHODS: We investigated the effect of T. cruzi infection on the expression and distribution of talin/paxillin and associated proteins in mouse cardiomyocytes in vitro by western blotting, immunofluorescence and quantitative real-time polymerase chain reaction (qRT-PCR). FINDINGS: Talin and paxillin spatial distribution in T. cruzi-infected cardiomyocytes in vitro were altered associated with a downregulation of these proteins and mRNAs levels at 72 h post-infection (hpi). Additionally, we observed an increase in the activation of the focal adhesion kinase (FAK) concomitant with increase in ß-1-integrin at 24 hpi. Finally, we detected a decrease in the activation of FAK at 72 hpi in T. cruzi-infected cultures. MAIN CONCLUSION: The results suggest that these changes may contribute to the mechanotransduction disturbance evidenced in chagasic cardiomyopathy.


Asunto(s)
Cardiomiopatía Chagásica/metabolismo , Miocitos Cardíacos/parasitología , Paxillin/metabolismo , Talina/metabolismo , Trypanosoma cruzi/fisiología , Animales , Western Blotting , Técnica del Anticuerpo Fluorescente Indirecta , Immunoblotting , Mecanotransducción Celular/fisiología , Ratones , Reacción en Cadena en Tiempo Real de la Polimerasa
8.
Toxicon ; 162: 32-39, 2019 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-30849455

RESUMEN

Lonomia obliqua is a caterpillar of potential therapeutic interest whose venom is able to induce severe blood leakage and modulate leukocyte migration. Since both phenotypes are associated with changes in cytoskeleton dynamics and cell adhesion properties, the aim of this study was to analyze the effects of Lonomia obliqua bristle extract (LOBE) in cell adhesion and migration signaling. Proteomic analysis revealed that epithelial cells (CHO-K1) exposed to LOBE (30 µg/mL, 30 min) exhibited changes in levels of actin regulatory proteins, including RhoGTPases. These changes correlated with an increase in the activity of the RhoGTPase family member Rac as measured by Förster resonance energy transfer (FRET). When plated in migration promoting conditions, CHO-K1 cells exposed to LOBE (10 µg/mL) showed an increase in membrane ruffling after short (30 min) period of incubation that was accompanied by changes in the distribution of the adhesion markers paxillin, vinculin and an increase of focal adhesion kinase autophosphorylation levels (Y397), suggesting changes in cell-extracellular matrix (ECM) adhesion properties and signaling. These data suggest that LOBE possesses bioactive molecules that are capable to modulated cell migration signaling, cytoskeletal dynamics and cell-ECM properties of several cell types.


Asunto(s)
Venenos de Artrópodos/toxicidad , Adhesión Celular/efectos de los fármacos , Mariposas Nocturnas/química , Proteína de Unión al GTP rac1/metabolismo , Actinas/metabolismo , Animales , Células CHO , Movimiento Celular/efectos de los fármacos , Cricetulus , Citoesqueleto/fisiología , Larva/química , Paxillin/metabolismo , Fosforilación , Proteoma/análisis , Vinculina/metabolismo
9.
Cell Commun Signal ; 17(1): 27, 2019 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-30894182

RESUMEN

BACKGROUND: Integrins mediate cell adhesion, migration, and survival by connecting the intracellular machinery with the surrounding extracellular matrix. Previous studies demonstrated the interaction between αvß3 integrin and VEGF type 2 receptor (VEGFR2) in VEGF-induced angiogenesis. DisBa-01, a recombinant His-tag fusion, RGD-disintegrin from Bothrops alternatus snake venom, binds to αvß3 integrin with nanomolar affinity blocking cell adhesion to the extracellular matrix. Here we present in vitro evidence of a direct interference of DisBa-01 with αvß3/VEGFR2 cross-talk and its downstream pathways. METHODS: Human umbilical vein (HUVECs) were cultured in plates coated with fibronectin (FN) or vitronectin (VN) and tested for migration, invasion and proliferation assays in the presence of VEGF, DisBa-01 (1000 nM) or VEGF and DisBa-01 simultaneously. Phosphorylation of αvß3/VEGFR2 receptors and the activation of intracellular signaling pathways were analyzed by western blotting. Morphological alterations were observed and quantified by fluorescence confocal microscopy. RESULTS: DisBa-01 treatment of endothelial cells inhibited critical steps of VEGF-mediated angiogenesis such as migration, invasion and tubulogenesis. The blockage of αvß3/VEGFR2 cross-talk by this disintegrin decreases protein expression and phosphorylation of VEGFR2 and ß3 integrin subunit, regulates FAK/SrC/Paxillin downstream signals, and inhibits ERK1/2 and PI3K pathways. These events result in actin re-organization and inhibition of HUVEC migration and adhesion. Labelled-DisBa-01 colocalizes with αvß3 integrin and VEGFR2 in treated cells. CONCLUSIONS: Disintegrin inhibition of αvß3 integrin blocks VEGFR2 signalling, even in the presence of VEGF, which impairs the angiogenic mechanism. These results improve our understanding concerning the mechanisms of pharmacological inhibition of angiogenesis.


Asunto(s)
Movimiento Celular/efectos de los fármacos , Venenos de Crotálidos/farmacología , Desintegrinas/farmacología , Células Endoteliales de la Vena Umbilical Humana , Integrina alfaVbeta3/metabolismo , Transducción de Señal/efectos de los fármacos , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Adhesión Celular , Células Cultivadas , Quinasa 1 de Adhesión Focal/metabolismo , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Paxillin/metabolismo , Fosfatidilinositol 3-Quinasa/metabolismo , Familia-src Quinasas/metabolismo
10.
Mem. Inst. Oswaldo Cruz ; 114: e180593, 2019. graf
Artículo en Inglés | LILACS | ID: biblio-1020079

RESUMEN

BACKGROUND Cardiac physiology depends on coupling and electrical and mechanical coordination through the intercalated disc. Focal adhesions offer mechanical support and signal transduction events during heart contraction-relaxation processes. Talin links integrins to the actin cytoskeleton and serves as a scaffold for the recruitment of other proteins, such as paxillin in focal adhesion formation and regulation. Chagasic cardiomyopathy is caused by infection by Trypanosoma cruzi and is a debilitating condition comprising extensive fibrosis, inflammation, cardiac hypertrophy and electrical alterations that culminate in heart failure. OBJECTIVES Since mechanotransduction coordinates heart function, we evaluated the underlying mechanism implicated in the mechanical changes, focusing especially in mechanosensitive proteins and related signalling pathways during infection of cardiac cells by T. cruzi. METHODS We investigated the effect of T. cruzi infection on the expression and distribution of talin/paxillin and associated proteins in mouse cardiomyocytes in vitro by western blotting, immunofluorescence and quantitative real-time polymerase chain reaction (qRT-PCR). FINDINGS Talin and paxillin spatial distribution in T. cruzi-infected cardiomyocytes in vitro were altered associated with a downregulation of these proteins and mRNAs levels at 72 h post-infection (hpi). Additionally, we observed an increase in the activation of the focal adhesion kinase (FAK) concomitant with increase in β-1-integrin at 24 hpi. Finally, we detected a decrease in the activation of FAK at 72 hpi in T. cruzi-infected cultures. MAIN CONCLUSION The results suggest that these changes may contribute to the mechanotransduction disturbance evidenced in chagasic cardiomyopathy.


Asunto(s)
Animales , Ratones , Trypanosoma cruzi/fisiología , Cardiomiopatía Chagásica/metabolismo , Miocitos Cardíacos/parasitología , Mecanotransducción Celular/genética , Western Blotting , Reacción en Cadena de la Polimerasa , Técnica del Anticuerpo Fluorescente , Paxillin/metabolismo
11.
J Hematol Oncol ; 10(1): 50, 2017 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-28214467

RESUMEN

Paxilllin is a multifunctional and multidomain focal adhesion adapter protein which serves an important scaffolding role at focal adhesions by recruiting structural and signaling molecules involved in cell movement and migration, when phosphorylated on specific Tyr and Ser residues. Upon integrin engagement with extracellular matrix, paxillin is phosphorylated at Tyr31, Tyr118, Ser188, and Ser190, activating numerous signaling cascades which promote cell migration, indicating that the regulation of adhesion dynamics is under the control of a complex display of signaling mechanisms. Among them, paxillin disassembly from focal adhesions induced by extracellular regulated kinase (ERK)-mediated phosphorylation of serines 106, 231, and 290 as well as the binding of the phosphatase PEST to paxillin have been shown to play a key role in cell migration. Paxillin also coordinates the spatiotemporal activation of signaling molecules, including Cdc42, Rac1, and RhoA GTPases, by recruiting GEFs, GAPs, and GITs to focal adhesions. As a major participant in the regulation of cell movement, paxillin plays distinct roles in specific tissues and developmental stages and is involved in immune response, epithelial morphogenesis, and embryonic development. Importantly, paxillin is also an essential player in pathological conditions including oxidative stress, inflammation, endothelial cell barrier dysfunction, and cancer development and metastasis.


Asunto(s)
Movimiento Celular , Paxillin/metabolismo , Animales , Adhesiones Focales/metabolismo , Humanos , Patología Molecular , Fosforilación , Transducción de Señal
12.
Mol Cell Endocrinol ; 430: 1-11, 2016 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-27130522

RESUMEN

Breast cancer is the most common malignancy in women, with metastases being the cause of death in 98%. In previous works we have demonstrated that retinoic acid (RA), the main retinoic acid receptor (RAR) ligand, is involved in the metastatic process by inhibiting migration through a reduced expression of the specific migration-related proteins Moesin, c-Src, and FAK. At present, our hypothesis is that RA also acts for short periods in a non-genomic action to cooperate with motility reduction and morphology of breast cancer cells. Here we identify that the administration of 10(-6) M RA (10-20 min) induces the activation of the migration-related proteins Moesin, FAK, and Paxillin in T-47D breast cancer cells. The phosphorylation exerted by the selective agonists for RARα and RARß, on Moesin, FAK, and Paxillin was comparable to the activation exerted by RA. The RARγ agonist only led to a weak activation, suggesting the involvement of RARα and RARß in this pathway. We then treated the cells with different inhibitors that are involved in cell signaling to regulate the mechanisms of cell motility. RA failed to activate Moesin, FAK, and Paxillin in cells treated with Src inhibitor (PP2) and PI3K inhibitor (WM), suggesting the participation of Src-PI3K in this pathway. Treatment with 10(-6) M RA for 20 min significantly decreased cell adhesion. However, when cells were treated with 10(-6) M RA and FAK inhibitor, the RA did not significantly inhibit adhesion, suggesting a role of FAK in the adhesion inhibited by RA. By immunofluorescence and immunoblotting analysis we demonstrated that RA induced nuclear FAK translocation leading to a reduced cellular adhesion. These findings provide new information on the actions of RA for short periods. RA participates in cell adhesion and subsequent migration, modulating the relocation and activation of proteins involved in cell migration.


Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Núcleo Celular/metabolismo , Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Proteínas de Microfilamentos/metabolismo , Paxillin/metabolismo , Tretinoina/farmacología , Adhesión Celular/efectos de los fármacos , Línea Celular Tumoral , Núcleo Celular/efectos de los fármacos , Femenino , Proteínas de Choque Térmico HSP27/metabolismo , Proteínas del Choque Térmico HSP72 , Humanos , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación , Transporte de Proteínas/efectos de los fármacos , Receptores de Ácido Retinoico/agonistas , Receptores de Ácido Retinoico/metabolismo , Receptor alfa de Ácido Retinoico/agonistas , Receptor alfa de Ácido Retinoico/metabolismo , Transducción de Señal/efectos de los fármacos , Proteína p53 Supresora de Tumor/metabolismo , Familia-src Quinasas/metabolismo
13.
J Cell Biochem ; 117(9): 2170-81, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27061092

RESUMEN

Adrenocorticotropic hormone (ACTH) treatment has been proven to promote paxillin dephosphorylation and increase soluble protein tyrosine phosphatase (PTP) activity in rat adrenal zona fasciculata (ZF). Also, in-gel PTP assays have shown the activation of a 115-kDa PTP (PTP115) by ACTH. In this context, the current work presents evidence that PTP115 is PTP-PEST, a PTP that recognizes paxillin as substrate. PTP115 was partially purified from rat adrenal ZF and PTP-PEST was detected through Western blot in bioactive samples taken in each purification step. Immunohistochemical and RT-PCR studies revealed PTP-PEST expression in rat ZF and Y1 adrenocortical cells. Moreover, a PTP-PEST siRNA decreased the expression of this phosphatase. PKA phosphorylation of purified PTP115 isolated from non-ACTH-treated rats increased KM and VM . Finally, in-gel PTP assays of immunoprecipitated paxillin from control and ACTH-treated rats suggested a hormone-mediated increase in paxillin-PTP115 interaction, while PTP-PEST and paxillin co-localize in Y1 cells. Taken together, these data demonstrate PTP-PEST expression in adrenal ZF and its regulation by ACTH/PKA and also suggest an ACTH-induced PTP-PEST-paxillin interaction. J. Cell. Biochem. 117: 2170-2181, 2016. © 2016 The Authors. Journal of Cellular Biochemistry Published by Wiley Periodicals, Inc.


Asunto(s)
Hormona Adrenocorticotrópica/farmacología , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Paxillin/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 12/biosíntesis , Zona Fascicular/metabolismo , Animales , Línea Celular Tumoral , Proteínas Quinasas Dependientes de AMP Cíclico/genética , Ratones , Paxillin/genética , Unión Proteica/efectos de los fármacos , Proteína Tirosina Fosfatasa no Receptora Tipo 12/genética , Ratas , Zona Fascicular/citología
14.
Mol Cell Endocrinol ; 430: 56-67, 2016 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-27095481

RESUMEN

Breast cancer is the major cause of cancer-related death in women. Its treatment is particularly difficult when metastasis occurs. The ability of cancer cells to move and invade the surrounding environment is the basis of local and distant metastasis. Cancer cells are able to remodel the actin cytoskeleton, which requires the recruitment of numerous structural and regulatory proteins that modulate actin filaments dynamics, including Paxillin or the Neural Wiskott-Aldrich Syndrome Protein (N-WASP). We show that 17-ß estradiol (E2) induces phosphorylation of Paxillin and its translocation toward membrane sites where focal adhesion complexes are assembled. This cascade is triggered by a Gαi1/Gß protein-dependent signaling of estrogen receptor α (ERα) to c-Src, focal adhesion kinase (FAK) and Paxillin. Within this complex, activated Paxillin recruits the small GTPase Cdc42, which triggers N-WASP phosphorylation. This results in the redistribution of Arp2/3 complexes at sites where membrane structures related to cell movement are formed. Recruitment of Paxillin, Cdc42 and N-WASP is necessary for cell adhesion, migration and invasion induced by E2 in breast cancer cells. In parallel, we investigated whether Raloxifene (RAL), a selective estrogen receptor modulator (SERMs), could inhibit or revert the effects of E2 in breast cancer cell movement. We found that, in the presence of E2, RAL acts as an ER antagonist and displays an inhibitory effect on estrogen-promoted cell adhesion and migration via FAK/Paxillin/N-WASP. Our findings identify an original mechanism through which estrogen regulates breast cancer cell motility and invasion via Paxillin. These results may have clinical relevance for the development of new therapeutic strategies for cancer treatment.


Asunto(s)
Complejo 2-3 Proteico Relacionado con la Actina/metabolismo , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Estrógenos/metabolismo , Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Paxillin/metabolismo , Transducción de Señal , Proteína Neuronal del Síndrome de Wiskott-Aldrich/metabolismo , Citoesqueleto de Actina/efectos de los fármacos , Citoesqueleto de Actina/metabolismo , Adhesión Celular/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Receptor alfa de Estrógeno/metabolismo , Femenino , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/metabolismo , Subunidades beta de la Proteína de Unión al GTP/metabolismo , Humanos , Invasividad Neoplásica , Fosforilación/efectos de los fármacos , Transporte de Proteínas/efectos de los fármacos , Clorhidrato de Raloxifeno/farmacología , Transducción de Señal/efectos de los fármacos , Proteína de Unión al GTP cdc42/metabolismo , Familia-src Quinasas/metabolismo
15.
Eur Urol ; 69(4): 710-719, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26159288

RESUMEN

BACKGROUND: Low-risk patients suffering from prostate cancer (PCa) are currently placed under active surveillance rather than undergoing radical prostatectomy. However, clear parameters for selecting the right patient for each strategy are not available, and new biomarkers and treatment modalities are needed. Low-molecular-weight protein tyrosine phosphatase (LMWPTP) could present such a target. OBJECTIVE: To correlate expression levels of LMWPTP in primary PCa to clinical outcome, and determine the role of LMWPTP in prostate tumor cell biology. DESIGN, SETTING, AND PARTICIPANTS: Acid phosphatase 1, soluble (ACP1) expression was analyzed on microarray data sets, which were subsequently used in Ingenuity Pathway Analysis. Immunohistochemistry was performed on a tissue microarray containing material of 481 PCa patients whose clinicopathologic data were recorded. PCa cell line models were used to investigate the role of LMWPTP in cell proliferation, migration, adhesion, and anoikis resistance. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The association between LMWPTP expression and clinical and pathologic outcomes was calculated using chi-square correlations and multivariable Cox regression analysis. Functional consequences of LMWPTP overexpression or downregulation were determined using migration and adhesion assays, confocal microscopy, Western blotting, and proliferation assays. RESULTS AND LIMITATIONS: LMWPTP expression was significantly increased in human PCa and correlated with earlier recurrence of disease (hazard ratio [HR]:1.99; p<0.001) and reduced patient survival (HR: 1.53; p=0.04). Unbiased Ingenuity analysis comparing cancer and normal prostate suggests migratory propensities in PCa. Indeed, overexpression of LMWPTP increases PCa cell migration, anoikis resistance, and reduces activation of focal adhesion kinase/paxillin, corresponding to decreased adherence. CONCLUSIONS: Overexpression of LMWPTP in PCa confers a malignant phenotype with worse clinical outcome. Prospective follow-up should determine the clinical potential of LMWPTP overexpression. PATIENT SUMMARY: These findings implicate low-molecular-weight protein tyrosine phosphatase as a novel oncogene in prostate cancer and could offer the possibility of using this protein as biomarker or target for treatment of this disease.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Movimiento Celular , Neoplasias de la Próstata/enzimología , Proteínas Tirosina Fosfatasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Anciano , Anoicis , Biomarcadores de Tumor/genética , Adhesión Celular , Línea Celular Tumoral , Proliferación Celular , Distribución de Chi-Cuadrado , Quinasa 1 de Adhesión Focal/metabolismo , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Peso Molecular , Análisis Multivariante , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia , Selección de Paciente , Paxillin/metabolismo , Valor Predictivo de las Pruebas , Pronóstico , Modelos de Riesgos Proporcionales , Prostatectomía , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/terapia , Proteínas Tirosina Fosfatasas/genética , Proteínas Proto-Oncogénicas/genética , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Análisis de Matrices Tisulares , Transfección , Regulación hacia Arriba , Espera Vigilante
16.
Infect Immun ; 82(6): 2255-65, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24643541

RESUMEN

EspC is a non-locus of enterocyte effacement (LEE)-encoded autotransporter produced by enteropathogenic Escherichia coli (EPEC) that is secreted to the extracellular milieu by a type V secretion system and then translocated into epithelial cells by the type III secretion system. Here, we show that this efficient EspC delivery into the cell leads to a cytopathic effect characterized by cell rounding and cell detachment. Thus, EspC is the main protein involved in epithelial cell cytotoxicity detected during EPEC adhesion and pedestal formation assays. The cell detachment phenotype is triggered by cytoskeletal and focal adhesion disruption. EspC-producing EPEC is able to cleave fodrin, paxillin, and focal adhesion kinase (FAK), but these effects are not observed when cells are infected with an espC isogenic mutant. Recovery of these phenotypes by complementing the mutant with the espC gene but not with the espC gene mutated in the serine protease motif highlights the role of the protease activity of EspC in the cell detachment phenotype. In vitro assays using purified proteins showed that EspC, but not EspC with an S256I substitution [EspCS256I], directly cleaves these cytoskeletal and focal adhesion proteins. Kinetics of protein degradation indicated that EspC-producing EPEC first cleaves fodrin (within the 11th and 9th repetitive units at the Q1219 and D938 residues, respectively), and this event sequentially triggers paxillin degradation, FAK dephosphorylation, and FAK degradation. Thus, cytoskeletal and focal adhesion protein cleavage leads to the cell rounding and cell detachment promoted by EspC-producing EPEC.


Asunto(s)
Adhesión Bacteriana/fisiología , Proteínas Portadoras/metabolismo , Escherichia coli Enteropatógena/patogenicidad , Células Epiteliales/metabolismo , Proteínas de Escherichia coli/fisiología , Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Proteínas de Microfilamentos/metabolismo , Paxillin/metabolismo , Adhesión Celular , Línea Celular , Células Epiteliales/patología , Infecciones por Escherichia coli/microbiología , Humanos
17.
Salvador; s.n; 2014. 145 p. ilus.
Tesis en Portugués | LILACS | ID: biblio-1000981

RESUMEN

As ORFs I e IV do genoma do HTLV-1 codificam, respectivamente, as proteínas p12/p8 (acessória) e Tax (regulatória). p12/p8, de 99 aminoácidos, pode ser clivada em sua extremidade amino terminal gerando a proteína p8. A primeira clivagem proteolítica de p12 remove o sinal de retenção ao RE, enquanto a segunda clivagem, gera o produto de 8kDa, referido como p8. p12 localiza-se no sistema de endomembranes, residindo em RE e aparato de Golgi, enquanto p8 dirige-se para a membrana plasmática, onde é recrutada para a sinapse imunológica, através da ligação com o receptor de células T (TCR), além de participar da sinapse virológica e da formação de conduítes. A proteína Tax, por outro lado, atua como transativador transcricional do HTLV-1, sendo referida também na indução da expressão de diversos genes celulares, aumentando a proliferação e a migração das células infectadas. Na via de transporte de vesículas secretórias, vesículas produzidas como pós-Golgi são transportadas ao longo do citoesqueleto por motores celulares. A Miosina-Va, um motor não convencional, transporta diversos cargos, incluindo vesículas secretórias, vesículas sinápticas e de retículo endoplasmático. Outra proteína relacionada ao citoesqueleto é a Paxilina, que atua como molécula adaptadora nas adesões focais e cuja expressão está aumentada em indivíduos TSP-HAM...


HTLV-1 ORFs I and IV encode respectively p12/p8 (accessory protein) and Tax (regulatory protein). The 99 amino acid p12 protein can be proteolytically cleaved at the amino terminus to generate the p8 protein. The first proteolytic cleavage removes the ER retention/retrieval signal at the amino terminus of p12, while the second cleavage generates the p8 protein. The p12 protein localizes to cellular endomembranes, within the ER and Golgi apparatus, while p8 traffics to lipid rafts at the cell surface and is recruited to the immunological synapse upon T-cell receptor (TCR) ligation, virological synapse and conduits. Tax on the other hand acts as viral transactivator and induces expression of many cellular genes, increasing proliferation and migration of infected cells. In secretory vesicle transport, vesicles produced as post-Golgi are moved along the cytoskeleton by motor proteins. The unconventional myosin motor, Myosin-Va, moves several cargoes including secretory vesicles, synaptic vesicles, and the endoplasmic reticulum. Another cytoskeleton associated protein is Paxillin, an adapter on focal adhesions which expression is increased in TSP-HAM patients...


Asunto(s)
Humanos , Paxillin/biosíntesis , Paxillin/toxicidad , Paxillin/ultraestructura , Productos del Gen tax/análisis , Productos del Gen tax/inmunología , Productos del Gen tax/aislamiento & purificación , Productos del Gen tax/sangre , Productos del Gen tax/síntesis química , Virus Linfotrópico T Tipo 1 Humano/inmunología , Virus Linfotrópico T Tipo 1 Humano/patogenicidad
18.
J Cell Sci ; 126(Pt 17): 3835-47, 2013 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-23813952

RESUMEN

Migration and invasion are essential steps associated with tumor cell metastasis and increasing evidence points towards endosome trafficking being essential in this process. Indeed, the small GTPase Rab5, a crucial regulator of early endosome dynamics, promotes cell migration in vitro and in vivo. Precisely how Rab5 participates in these events remains to be determined. Considering that focal adhesions represent structures crucial to cell migration, we specifically asked whether Rab5 activation promoted focal adhesion disassembly and thereby facilitated migration and invasion of metastatic cancer cells. Pulldown and biosensor assays revealed that Rab5-GTP loading increased at the leading edge of migrating tumor cells. Additionally, targeting of Rab5 by different shRNA sequences, but not control shRNA, decreased Rab5-GTP levels, leading to reduced cell spreading, migration and invasiveness. Re-expression in knockdown cells of wild-type Rab5, but not the S34N mutant (GDP-bound), restored these properties. Importantly, Rab5 association with the focal adhesion proteins vinculin and paxillin increased during migration, and expression of wild-type, but not GDP-bound Rab5, accelerated focal adhesion disassembly, as well as FAK dephosphorylation on tyrosine 397. Finally, Rab5-driven invasiveness required focal adhesion disassembly, as treatment with the FAK inhibitor number 14 prevented Matrigel invasion and matrix metalloproteinase release. Taken together, these observations show that Rab5 activation is required to enhance cancer cell migration and invasion by promoting focal adhesion disassembly.


Asunto(s)
Neoplasias de la Mama/metabolismo , Adhesión Celular/fisiología , Adhesiones Focales/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas de Unión al GTP rab5/metabolismo , Línea Celular Tumoral , Movimiento Celular , Activación Enzimática , Femenino , Humanos , Invasividad Neoplásica , Metástasis de la Neoplasia , Paxillin/metabolismo , Interferencia de ARN , ARN Interferente Pequeño , Vinculina/metabolismo , Proteínas de Unión al GTP rab5/genética
19.
Sao Paulo Med J ; 131(2): 71-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23657508

RESUMEN

CONTEXT AND OBJECTIVE: The possible role of adhesion molecules in early breast carcinogenesis has been shown in the literature. We aimed to analyze early adhesion imbalances in non-nodular breast lesions and their association with precursor lesions, in order to ascertain whether these alterations exist and contribute towards early carcinogenesis. DESIGN AND SETTING: Retrospective cross-sectional study based on medical records at a private radiological clinic in São Paulo, Brazil. METHODS: We retrospectively reviewed the medical records of all consecutive women attended between August 2006 and July 2007 who presented mammographic evidence of breast microcalcifications classified as Breast Imaging Reporting and Data System Atlas (BI-RADS) type 4. These women underwent stereotaxic biopsy. Clinical, radiological and pathological data were collected, and immunohistochemical assays searched for claudin, paxillin, FRA-1 and HER-2. RESULTS: Over this period, 127 patients were evaluated. Previous BI-RADS diagnoses showed that 69 cases were in category 4A, 47 in 4B and 11 in 4C. Morphological assessment showed benign entities in 86.5%. Most of the benign lesions showed preserved claudin expression, associated with paxillin (P < 0.001). Paxillin and HER-2 expressions were correlated. FRA-1 expression was also strongly associated with HER-2 expression (P < 0.001). CONCLUSIONS: Although already present in smaller amounts, imbalance of adhesion molecules is not necessarily prevalent in non-nodular breast lesions. Since FRA-1 expression reached statistically significant correlations with radiological and morphological diagnoses and HER-2 status, it may have a predictive role in this setting.


Asunto(s)
Calcinosis/metabolismo , Claudinas/análisis , Paxillin/análisis , Proteínas Proto-Oncogénicas c-fos/análisis , Receptor ErbB-2/análisis , Anticuerpos Monoclonales , Biomarcadores de Tumor/análisis , Mama/patología , Neoplasias de la Mama/química , Neoplasias de la Mama/patología , Calcinosis/patología , Métodos Epidemiológicos , Femenino , Humanos , Hiperplasia/metabolismo , Hiperplasia/patología , Lesiones Precancerosas/química , Lesiones Precancerosas/patología
20.
São Paulo med. j ; São Paulo med. j;131(2): 71-79, abr. 2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-671680

RESUMEN

CONTEXT AND OBJECTIVE The possible role of adhesion molecules in early breast carcinogenesis has been shown in the literature. We aimed to analyze early adhesion imbalances in non-nodular breast lesions and their association with precursor lesions, in order to ascertain whether these alterations exist and contribute towards early carcinogenesis. DESIGN AND SETTING Retrospective cross-sectional study based on medical records at a private radiological clinic in São Paulo, Brazil. METHODS We retrospectively reviewed the medical records of all consecutive women attended between August 2006 and July 2007 who presented mammographic evidence of breast microcalcifications classified as Breast Imaging Reporting and Data System Atlas (BI-RADS) type 4. These women underwent stereotaxic biopsy. Clinical, radiological and pathological data were collected, and immunohistochemical assays searched for claudin, paxillin, FRA-1 and HER-2. RESULTS Over this period, 127 patients were evaluated. Previous BI-RADS diagnoses showed that 69 cases were in category 4A, 47 in 4B and 11 in 4C. Morphological assessment showed benign entities in 86.5%. Most of the benign lesions showed preserved claudin expression, associated with paxillin (P < 0.001). Paxillin and HER-2 expressions were correlated. FRA-1 expression was also strongly associated with HER-2 expression (P < 0.001). CONCLUSIONS Although already present in smaller amounts, imbalance of adhesion molecules is not necessarily prevalent in non-nodular breast lesions. Since FRA-1 expression reached statistically significant correlations with radiological and morphological diagnoses and HER-2 status, it may have a predictive role in this setting. .


CONTEXTO E OBJETIVO A literatura tem mostrado a importância de moléculas de adesão na carcinogênese precoce de mama. Objetivamos analisar desequilíbrios precoces de adesão em lesões não nodulares da mama e associação com lesões precursoras, a fim de verificar se essas alterações existem e contribuem com a carcinogênese. TIPO DE ESTUDO E LOCAL Estudo retrospectivo baseado em prontuários médicos, numa clínica radiológica privada em São Paulo, Brasil. MÉTODOS Revisamos retrospectivamente prontuários de todas as mulheres consecutivamente atendidas com evidência mamográfica de microcalcificações mamárias, classificadas como tipo 4 do Breast Imaging Reporting and Data System Atlas (BI-RADS) entre agosto de 2006 e julho de 2007. Elas foram submetidas a biópsia estereotáxica. Dados clínicos, radiológicos e histopatológicos foram coletados e ensaios de imunoistoquímica procuraram por claudina, paxilina, HER-2 e FRA-1. RESULTADOS No período, 127 pacientes foram avaliadas. Diagnósticos de BI-RADS anteriores tinham 69 casos na categoria 4A, 47 em 4B, e 11 em 4C. A avaliação morfológica mostrou entidades benignas em 86,5%. A maioria das lesões benignas mostrou expressão preservada de claudina, associada a paxilina (P < 0,001). Expressões de paxilina e HER-2 foram correlacionadas. Expressão de FRA-1 associou-se à de HER-2 (P < 0,001). CONCLUSÕES Embora já presente em menor quantidade, o desequilíbrio de moléculas de adesão não é necessariamente prevalente em lesões mamárias nodulares e talvez a expressão de FRA-1 possa ter um papel preditivo neste cenário, uma vez que atingiu correlações ...


Asunto(s)
Femenino , Humanos , Calcinosis/metabolismo , Claudinas/análisis , Paxillin/análisis , Proteínas Proto-Oncogénicas c-fos/análisis , /análisis , Anticuerpos Monoclonales , Neoplasias de la Mama/química , Neoplasias de la Mama/patología , Mama/patología , Calcinosis/patología , Métodos Epidemiológicos , Hiperplasia/metabolismo , Hiperplasia/patología , Lesiones Precancerosas/química , Lesiones Precancerosas/patología , Biomarcadores de Tumor/análisis
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