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BACKGROUND: The C-terminal-binding protein 1/brefeldin A ADP-ribosylation substrate (CtBP1/BARS) acts both as an oncogenic transcriptional co-repressor and as a fission inducing protein required for membrane trafficking and Golgi complex partitioning during mitosis, hence for mitotic entry. CtBP1/BARS overexpression, in multiple cancers, has pro-tumorigenic functions regulating gene networks associated with "cancer hallmarks" and malignant behavior including: increased cell survival, proliferation, migration/invasion, epithelial-mesenchymal transition (EMT). Structurally, CtBP1/BARS belongs to the hydroxyacid-dehydrogenase family and possesses a NAD(H)-binding Rossmann fold, which, depending on ligands bound, controls the oligomerization of CtBP1/BARS and, in turn, its cellular functions. Here, we proposed to target the CtBP1/BARS Rossmann fold with small molecules as selective inhibitors of mitotic entry and pro-tumoral transcriptional activities. METHODS: Structured-based screening of drug databases at different development stages was applied to discover novel ligands targeting the Rossmann fold. Among these identified ligands, N-(3,4-dichlorophenyl)-4-{[(4-nitrophenyl)carbamoyl]amino}benzenesulfonamide, called Comp.11, was selected for further analysis. Fluorescence spectroscopy, isothermal calorimetry, computational modelling and site-directed mutagenesis were employed to define the binding of Comp.11 to the Rossmann fold. Effects of Comp.11 on the oligomerization state, protein partners binding and pro-tumoral activities were evaluated by size-exclusion chromatography, pull-down, membrane transport and mitotic entry assays, Flow cytometry, quantitative real-time PCR, motility/invasion, and colony assays in A375MM and B16F10 melanoma cell lines. Effects of Comp.11 on tumor growth in vivo were analyzed in mouse tumor model. RESULTS: We identify Comp.11 as a new, potent and selective inhibitor of CtBP1/BARS (but not CtBP2). Comp.11 directly binds to the CtBP1/BARS Rossmann fold affecting the oligomerization state of the protein (unlike other known CtBPs inhibitors), which, in turn, hinders interactions with relevant partners, resulting in the inhibition of both CtBP1/BARS cellular functions: i) membrane fission, with block of mitotic entry and cellular secretion; and ii) transcriptional pro-tumoral effects with significantly hampered proliferation, EMT, migration/invasion, and colony-forming capabilities. The combination of these effects impairs melanoma tumor growth in mouse models. CONCLUSIONS: This study identifies a potent and selective inhibitor of CtBP1/BARS active in cellular and melanoma animal models revealing new opportunities to study the role of CtBP1/BARS in tumor biology and to develop novel melanoma treatments.
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Oxirredutases do Álcool , Proteínas de Ligação a DNA , Melanoma , Humanos , Oxirredutases do Álcool/antagonistas & inibidores , Oxirredutases do Álcool/metabolismo , Oxirredutases do Álcool/genética , Animais , Camundongos , Melanoma/tratamento farmacológico , Melanoma/patologia , Melanoma/metabolismo , Melanoma/genética , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/genética , Proliferação de Células/efeitos dos fármacos , Antineoplásicos/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Entry into mitosis requires not only correct DNA replication but also extensive cell reorganization, including the separation of the Golgi ribbon into isolated stacks. To understand the significance of pre-mitotic Golgi reorganization, we devised a strategy to first block Golgi segregation, with the consequent G2-arrest, and then force entry into mitosis. We found that the cells forced to enter mitosis with an intact Golgi ribbon showed remarkable cell division defects, including spindle multipolarity and binucleation. The spindle defects were caused by reduced levels at the centrosome of the kinase Aurora-A, a pivotal spindle formation regulator controlled by Golgi segregation. Overexpression of Aurora-A rescued spindle formation, indicating a crucial role of the Golgi-dependent recruitment of Aurora-A at the centrosome. Thus, our results reveal that alterations of the pre-mitotic Golgi segregation in G2 have profound consequences on the fidelity of later mitotic processes and represent potential risk factors for cell transformation and cancer development.
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Citocinese , Mitose , Complexo de Golgi , CentrossomoRESUMO
PURPOSE: Axillary Web Syndrome (AWS) is a common sequela after surgical axillary lymph node dissection (ALND) often manifesting with reduced range of motion (ROM) of the limb, which requires rehabilitation. Notwithstanding, a standardized rehabilitation protocol is currently lacking in clinical practice. Our primary objective was therefore to evaluate the effectiveness of the use of a snapping manual maneuver (SMM, used in our clinical practice) to increase ROM during abduction (ABD) when compared with a standardized stretching exercise (SSE) protocol. A three-year follow-up of the enrolled patients was also carried out to determine the incidence of Breast Cancer-Related Lymphedema (BCRL). MATERIALS AND METHODS: Between July 2013 and January 2019, we conducted a single-blinded randomized clinical trial. A total of 60 patients, who underwent ALND in our hospital, came to our clinic under medical advice or on voluntary access and reported AWS symptoms. The patients were randomly assigned into two equally divided groups. The treatment of group one consists in the execution of a supervised SSEs protocol, while group two additionally received a manual snapping maneuver. Patients of both groups received two treatment sessions within two weeks. At the end of the session, they were asked to continue the exercises autonomously on a daily basis, three times per day, for one month. RESULTS: There were no statically significant differences in ROM at our one-month follow-up and the incidence of BCRL was equally distributed after three years. CONCLUSIONS: The use of the manual snapping maneuver in addition to stretching once per week for two weeks does not appear to improve the outcome of the patients in comparison with stretching alone and does not appear to be related to lymphedema in our 3 years follow-up.
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Linfedema , Ombro , Humanos , Progressão da Doença , Exercício Físico , Extremidades , Linfedema/etiologia , Linfedema/terapia , Amplitude de Movimento Articular , AxilaRESUMO
Importance: Sentinel lymph node biopsy (SLNB) is the standard of care for axillary node staging of patients with early breast cancer (BC), but its necessity can be questioned since surgery for examination of axillary nodes is not performed with curative intent. Objective: To determine whether the omission of axillary surgery is noninferior to SLNB in patients with small BC and a negative result on preoperative axillary lymph node ultrasonography. Design, Setting, and Participants: The SOUND (Sentinel Node vs Observation After Axillary Ultra-Sound) trial was a prospective noninferiority phase 3 randomized clinical trial conducted in Italy, Switzerland, Spain, and Chile. A total of 1463 women of any age with BC up to 2 cm and a negative preoperative axillary ultrasonography result were enrolled and randomized between February 6, 2012, and June 30, 2017. Of those, 1405 were included in the intention-to-treat analysis. Data were analyzed from October 10, 2022, to January 13, 2023. Intervention: Eligible patients were randomized on a 1:1 ratio to receive SLNB (SLNB group) or no axillary surgery (no axillary surgery group). Main Outcomes and Measures: The primary end point of the study was distant disease-free survival (DDFS) at 5 years, analyzed as intention to treat. Secondary end points were the cumulative incidence of distant recurrences, the cumulative incidence of axillary recurrences, DFS, overall survival (OS), and the adjuvant treatment recommendations. Results: Among 1405 women (median [IQR] age, 60 [52-68] years) included in the intention-to-treat analysis, 708 were randomized to the SLNB group, and 697 were randomized to the no axillary surgery group. Overall, the median (IQR) tumor size was 1.1 (0.8-1.5) cm, and 1234 patients (87.8%) had estrogen receptor-positive ERBB2 (formerly HER2 or HER2/neu), nonoverexpressing BC. In the SLNB group, 97 patients (13.7%) had positive axillary nodes. The median (IQR) follow-up for disease assessment was 5.7 (5.0-6.8) years in the SLNB group and 5.7 (5.0-6.6) years in the no axillary surgery group. Five-year distant DDFS was 97.7% in the SLNB group and 98.0% in the no axillary surgery group (log-rank P = .67; hazard ratio, 0.84; 90% CI, 0.45-1.54; noninferiority P = .02). A total of 12 (1.7%) locoregional relapses, 13 (1.8%) distant metastases, and 21 (3.0%) deaths were observed in the SLNB group, and 11 (1.6%) locoregional relapses, 14 (2.0%) distant metastases, and 18 (2.6%) deaths were observed in the no axillary surgery group. Conclusions and Relevance: In this randomized clinical trial, omission of axillary surgery was noninferior to SLNB in patients with small BC and a negative result on ultrasonography of the axillary lymph nodes. These results suggest that patients with these features can be safely spared any axillary surgery whenever the lack of pathological information does not affect the postoperative treatment plan. Trial Registration: ClinicalTrials.gov Identifier: NCT02167490.
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Neoplasias da Mama , Biópsia de Linfonodo Sentinela , Humanos , Feminino , Pessoa de Meia-Idade , Biópsia de Linfonodo Sentinela/métodos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Neoplasias da Mama/mortalidade , Estudos Prospectivos , Resultados Negativos , Recidiva Local de Neoplasia/patologia , Linfonodos/diagnóstico por imagem , Linfonodos/cirurgia , Linfonodos/patologia , Ultrassonografia , RecidivaRESUMO
Circulating tumor cells (CTCs) are tumor cells that have penetrated the circulatory system preserving tumor properties and heterogeneity. Detection and characterization of CTCs has high potential clinical values and many technologies have been developed for CTC identification. These approaches remain challenged by the extraordinary rarity of CTCs and the difficulty of efficiently distinguishing cancer from the much larger number of white blood cells in the bloodstream. Consequently, there is still a need for efficient and rapid methods to capture the broad spectrum of tumor cells circulating in the blood. Herein, we exploit the peculiarities of cancer metabolism for discriminating cancer from WBCs. Using deuterated glucose and Raman microscopy we show that a) the known ability of cancer cells to take up glucose at greatly increased rates compared to non-cancer cells results in the lipid generation and accumulation into lipid droplets and, b) by contrast, leukocytes do not appear to generate visible LDs. The difference in LD abundance is such that it provides a reliable parameter for distinguishing cancer from blood cells. For LD sensitive detections in a cell at rates suitable for screening purposes, we test a polarization-sensitive digital holographic imaging (PSDHI) technique that detects the birefringent properties of the LDs. By using polarization-sensitive digital holographic imaging, cancer cells (prostate cancer, PC3 and hepatocarcinoma cells, HepG2) can be rapidly discriminated from leukocytes with reliability close to 100%. The combined Raman and PSDHI microscopy platform lays the foundations for the future development of a new label-free, simple and universally applicable cancer cells' isolation method.
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KDEL receptors (KDELRs) are ubiquitous seven-transmembrane domain proteins encoded by three mammalian genes. They bind to and retro-transport endoplasmic reticulum (ER)-resident proteins with a C-terminal Lys-Asp-Glu-Leu (KDEL) sequence or variants thereof. In doing this, KDELR participates in the ER quality control of newly synthesized proteins and the unfolded protein response. The binding of KDEL proteins to KDELR initiates signaling cascades involving three alpha subunits of heterotrimeric G proteins, Src family kinases, protein kinases A (PKAs), and mitogen-activated protein kinases (MAPKs). These signaling pathways coordinate membrane trafficking flows between secretory compartments and control the degradation of the extracellular matrix (ECM), an important step in cancer progression. Considering the basic cellular functions performed by KDELRs, their association with various diseases is not surprising. KDELR mutants unable to bind the collagen-specific chaperon heat-shock protein 47 (HSP47) cause the osteogenesis imperfecta. Moreover, the overexpression of KDELRs appears to be linked to neurodegenerative diseases that share pathological ER-stress and activation of the unfolded protein response (UPR). Even immune function requires a functional KDELR1, as its mutants reduce the number of T lymphocytes and impair antiviral immunity. Several studies have also brought to light the exploitation of the shuttle activity of KDELR during the intoxication and maturation/exit of viral particles. Based on the above, KDELRs can be considered potential targets for the development of novel therapeutic strategies for a variety of diseases involving proteostasis disruption, cancer progression, and infectious disease. However, no drugs targeting KDELR functions are available to date; rather, KDELR has been leveraged to deliver drugs efficiently into cells or improve antigen presentation.
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The biosynthetic transport route that constitutes the secretory pathway plays a fundamental role in the cell, providing to the synthesis and transport of around one third of human proteins and most lipids. Signaling molecules within autoregulatory circuits on the intracellular membranes of the secretory pathway regulate these processes, especially at the level of the Golgi complex. Indeed, cancer cells can hijack several of these signaling molecules, and therefore also the underlying regulated processes, to bolster their growth or gain more aggressive phenotypes. Here, we review the most important autoregulatory circuits acting on the Golgi, emphasizing the role of specific signaling molecules in cancer. In fact, we propose to draw awareness to highlight the Golgi-localized regulatory systems as potential targets in cancer therapy.
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Adenosine diphosphate (ADP)-ribosylation is a posttranslational modification involved in key regulatory events catalyzed by ADP-ribosyltransferases (ARTs). Substrate identification and localization of the mono-ADP-ribosyltransferase PARP12 at the trans-Golgi network (TGN) hinted at the involvement of ARTs in intracellular traffic. We find that Golgin-97, a TGN protein required for the formation and transport of a specific class of basolateral cargoes (e.g., E-cadherin and vesicular stomatitis virus G protein [VSVG]), is a PARP12 substrate. PARP12 targets an acidic cluster in the Golgin-97 coiled-coil domain essential for function. Its mutation or PARP12 depletion, delays E-cadherin and VSVG export and leads to a defect in carrier fission, hence in transport, with consequent accumulation of cargoes in a trans-Golgi/Rab11-positive intermediate compartment. In contrast, PARP12 does not control the Golgin-245-dependent traffic of cargoes such as tumor necrosis factor alpha (TNFα). Thus, the transport of different basolateral proteins to the plasma membrane is differentially regulated by Golgin-97 mono-ADP-ribosylation by PARP12. This identifies a selective regulatory mechanism acting on the transport of Golgin-97- vs. Golgin-245-dependent cargoes. Of note, PARP12 enzymatic activity, and consequently Golgin-97 mono-ADP-ribosylation, depends on the activation of protein kinase D (PKD) at the TGN during traffic. PARP12 is directly phosphorylated by PKD, and this is essential to stimulate PARP12 catalytic activity. PARP12 is therefore a component of the PKD-driven regulatory cascade that selectively controls a major branch of the basolateral transport pathway. We propose that through this mechanism, PARP12 contributes to the maintenance of E-cadherin-mediated cell polarity and cell-cell junctions.
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ADP-Ribosilação/fisiologia , Autoantígenos/metabolismo , Caderinas/metabolismo , Membrana Celular/metabolismo , Complexo de Golgi/metabolismo , Proteínas da Matriz do Complexo de Golgi/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Proteína Quinase C/metabolismo , Antígenos CD , Catálise , Células HeLa , Humanos , Transporte Proteico , Fator de Necrose Tumoral alfa , Rede trans-Golgi/metabolismoRESUMO
BACKGROUND: In the randomised, phase 3 equivalence trial on electron intraoperative radiotherapy (ELIOT), accelerated partial breast irradiation (APBI) with the use of intraoperative radiotherapy was associated with a higher rate of ipsilateral breast tumour recurrence (IBTR) than whole-breast irradiation (WBI) in patients with early-stage breast cancer. Here, we aimed to examine the planned long-term recurrence and survival outcomes from the ELIOT trial. METHODS: This single-centre, randomised, phase 3 equivalence trial was done at the European Institute of Oncology (Milan, Italy). Eligible women, aged 48-75 years with a clinical diagnosis of a unicentric breast carcinoma with an ultrasound diameter not exceeding 25 mm, clinically negative axillary lymph nodes, and who were suitable for breast-conserving surgery, were randomly assigned (1:1) via a web-based system, with a random permuted block design (block size of 16) and stratified by clinical tumour size, to receive post-operative WBI with conventional fractionation (50 Gy given as 25 fractions of 2 Gy, plus a 10 Gy boost), or 21 Gy intraoperative radiotherapy with electrons (ELIOT) in a single dose to the tumour bed during surgery. The trial was open label and no-one was masked to treatment group assignment. The primary endpoint was the occurrence of IBTR. The trial was designed assuming a 5-year IBTR rate of 3% in the WBI group and equivalence of the two groups, if the 5-year IBTR rate in the ELIOT group did not exceed a 2·5 times excess, corresponding to 7·5%. Overall survival was the secondary endpoint. The main analysis was done by intention to treat. The cumulative incidence of IBTR events and overall survival were assessed at 5, 10, and 15 years of follow-up. This trial is registered with ClinicalTrials.gov, NCT01849133. FINDINGS: Between Nov 20, 2000, and Dec 27, 2007, 1305 women were enrolled and randomly assigned: 654 to the WBI group and 651 to the ELIOT group. After a median follow-up of 12·4 years (IQR 9·7-14·7), 86 (7%) patients developed IBTR, with 70 (11%) cases in the ELIOT group and 16 (2%) in the WBI group, corresponding to an absolute excess of 54 IBTRs in the ELIOT group (HR 4·62, 95% CI 2·68-7·95, p<0·0001). In the ELIOT group, the 5-year IBTR rate was 4·2% (95% CI 2·8-5·9), the 10-year rate was 8·1% (6·1-10·3), and the 15-year rate was 12·6% (9·8-15·9). In the WBI group, the 5-year IBTR rate was 0·5% (95% CI 0·1-1·3), the 10-year rate was 1·1% (0·5-2·2), and the 15-year rate was 2·4% (1·4-4·0). At final follow-up on March 11, 2019, 193 (15%) women had died from any cause, with no difference between the two groups (98 deaths in the ELIOT group vs 95 in the WBI group; HR 1·03, 95% CI 0·77-1·36, p=0·85). In the ELIOT group, the overall survival rate was 96·8% (95% CI 95·1-97·9) at 5 years, 90·7% (88·2-92·7) at 10 years, and 83·4% (79·7-86·4) at 15 years; and in the WBI group, the overall survival rate was 96·8% (95·1-97·9) at 5 years, 92·7% (90·4-94·4) at 10 years, and 82·4% (78·5-85·6) at 15 years. We did not collect long-term data on adverse events. INTERPRETATION: The long-term results of this trial confirmed the higher rate of IBTR in the ELIOT group than in the WBI group, without any differences in overall survival. ELIOT should be offered to selected patients at low-risk of IBTR. FUNDING: Italian Association for Cancer Research, Jacqueline Seroussi Memorial Foundation for Cancer Research, Umberto Veronesi Foundation, American Italian Cancer Foundation, The Lombardy Region, and Italian Ministry of Health.
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Neoplasias da Mama/radioterapia , Elétrons/uso terapêutico , Recidiva Local de Neoplasia/epidemiologia , Adulto , Idoso , Mama/efeitos da radiação , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
Glycosphingolipids are important components of the plasma membrane where they modulate the activities of membrane proteins including signalling receptors. Glycosphingolipid synthesis relies on competing reactions catalysed by Golgi-resident enzymes during the passage of substrates through the Golgi cisternae. The glycosphingolipid metabolic output is determined by the position and levels of the enzymes within the Golgi stack, but the mechanisms that coordinate the intra-Golgi localisation of the enzymes are poorly understood. Here, we show that a group of sequentially-acting enzymes operating at the branchpoint among glycosphingolipid synthetic pathways binds the Golgi-localised oncoprotein GOLPH3. GOLPH3 sorts these enzymes into vesicles for intra-Golgi retro-transport, acting as a component of the cisternal maturation mechanism. Through these effects, GOLPH3 controls the sub-Golgi localisation and the lysosomal degradation rate of specific enzymes. Increased GOLPH3 levels, as those observed in tumours, alter glycosphingolipid synthesis and plasma membrane composition thereby promoting mitogenic signalling and cell proliferation. These data have medical implications as they outline a novel oncogenic mechanism of action for GOLPH3 based on glycosphingolipid metabolism.
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Proliferação de Células , Glicoesfingolipídeos/biossíntese , Complexo de Golgi/metabolismo , Proteínas de Membrana/metabolismo , Células Cultivadas , Células HeLa , Humanos , Lisossomos/metabolismo , Proteínas de Membrana/genética , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , Transdução de SinaisRESUMO
PURPOSE: To evaluate clinical results of catheter-based interstitial high-dose-rate (HDR) brachytherapy (BT) as adjuvant treatment in previously irradiated recurrent breast cancer. MATERIAL AND METHODS: Between January 2011 and September 2015, 31 consecutive patients with histologically confirmed recurrent breast cancer after conservative surgery and conventional whole breast radiotherapy, were retreated with a second conservative surgical resection and reirradiated with adjuvant interstitial HDR-BT. None of the brachytherapy implant was performed during the quadrantectomy procedure. A dose of 34 Gy in 10 fractions, 2 fractions per day, with a minimal interval of 6 hours was delivered. RESULTS: At the time of the implant, the median age of patients was 59.7 years (range, 39.3-74.9 years). The median time from first treatment until BT for local recurrence was 11.9 years (range, 2.5-27.8 years). The median interval between salvage surgery and BT was 3.6 months (range, 1-8.2 months). No acute epidermitis or soft tissue side effects higher than grade 2 were recorded, with good cosmetic results in all patients. Most of the patients presented grade 1-2 late side effects. Only one patient developed grade 3 liponecrosis. After a median follow-up of 73.7 months (range, 28.8-102.4 months), the overall survival and cancer specific survival were 87.1% and 90.3%, respectively; 5-year local control and 5-year progression-free survival rate were 90.3% and 83.9%, respectively. CONCLUSIONS: Our preliminary analysis showed that HDR-BT is a feasible treatment for partial breast reirradiation offering very low complications rate and fast procedure. Higher patients' cohort is warranted in order to define the role of this treatment modality in the breast conservative management of local recurrence.
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OBJECTIVES: We performed an observational prospective cohort study to investigate post-traumatic stress symptoms, emerging after cancer diagnosis, which could influence patients' short- and long-term adjustment to illness, in order to foster screening measures and management of psychological factors in daily clinical pathways. METHODS: Patients' post-traumatic stress symptoms, psychological well-being and perceived quality of life were assessed through standardised questionnaires. The Profile of Mood States questionnaire was administered at pre-operative assessment (T0), surgical admission (T1) and discharge from hospital (T2). The Impact of Event Scale and the State-Trait Anxiety Inventory were administered at T0, T1, T2 and 2 years after discharge (T3). At 2-year follow-up, women were also asked to rate their perceived quality of life on a 0-10 visual analogue scale. RESULTS: Between January 2014 and April 2015, 150 women were enrolled. Results showed that more than 90% of patients experienced post-traumatic stress symptoms after cancer diagnosis (14% with severe symptoms and 76.7% with moderate symptoms) and post-traumatic stress disorder (PTSD) symptoms that persisted up to the 2-year from discharge follow-up, with significant improvement only 2 years after hospital discharge. In particular, mediation models showed that intrusive thoughts impede mood adjustment to the disease during the pre-surgical phase, with anxiety amplifying the negative effect, while symptoms of avoidance are more detrimental in the long term for patients' quality of life. CONCLUSION: PTSD symptom clusters have different influence on short- and long-term reaction to illness. Based on this evidence, appropriate interventions to manage PTSDs in the context of oncology should be developed.
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Celiac Disease (CD) is an autoimmune disease characterized by inflammation of the intestinal mucosa due to an immune response to wheat gliadins. Some gliadin peptides (e.g., A-gliadin P57-68) induce an adaptive Th1 pro-inflammatory response. Other gliadin peptides (e.g., A-gliadin P31-43) induce a stress/innate immune response involving interleukin 15 (IL15) and interferon α (IFN-α). In the present study, we describe a stressed/inflamed celiac cellular phenotype in enterocytes and fibroblasts probably due to an alteration in the early-recycling endosomal system. Celiac cells are more sensitive to the gliadin peptide P31-43 and IL15 than controls. This phenotype is reproduced in control cells by inducing a delay in early vesicular trafficking. This constitutive lesion might mediate the stress/innate immune response to gliadin, which can be one of the triggers of the gliadin-specific T-cell response.
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Doença Celíaca/imunologia , Gliadina/imunologia , Fragmentos de Peptídeos/imunologia , Adolescente , Estudos de Casos e Controles , Doença Celíaca/metabolismo , Doença Celíaca/patologia , Criança , Pré-Escolar , Endocitose/imunologia , Endossomos/imunologia , Endossomos/metabolismo , Enterócitos/imunologia , Enterócitos/metabolismo , Enterócitos/patologia , Receptores ErbB/metabolismo , Fibroblastos/imunologia , Fibroblastos/metabolismo , Fibroblastos/patologia , Gliadina/metabolismo , Humanos , Imunidade Inata , Interleucina-15/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Fragmentos de Peptídeos/metabolismo , Células Th1/imunologiaRESUMO
BACKGROUND: Shp1, a tyrosine-phosphatase-1 containing the Src-homology 2 (SH2) domain, is involved in inflammatory and immune reactions, where it regulates diverse signalling pathways, usually by limiting cell responses through dephosphorylation of target molecules. Moreover, Shp1 regulates actin dynamics. One Shp1 target is Src, which controls many cellular functions including actin dynamics. Src has been previously shown to be activated by a signalling cascade initiated by the cytosolic-phospholipase A2 (cPLA2) metabolite glycerophosphoinositol 4-phosphate (GroPIns4P), which enhances actin polymerisation and motility. While the signalling cascade downstream Src has been fully defined, the mechanism by which GroPIns4P activates Src remains unknown. METHODS: Affinity chromatography, mass spectrometry and co-immunoprecipitation studies were employed to identify the GroPIns4P-interactors; among these Shp1 was selected for further analysis. The specific Shp1 residues interacting with GroPIns4P were revealed by NMR and validated by site-directed mutagenesis and biophysical methods such as circular dichroism, isothermal calorimetry, fluorescence spectroscopy, surface plasmon resonance and computational modelling. Morphological and motility assays were performed in NIH3T3 fibroblasts. RESULTS: We find that Shp1 is the direct cellular target of GroPIns4P. GroPIns4P directly binds to the Shp1-SH2 domain region (with the crucial residues being Ser 118, Arg 138 and Ser 140) and thereby promotes the association between Shp1 and Src, and the dephosphorylation of the Src-inhibitory phosphotyrosine in position 530, resulting in Src activation. As a consequence, fibroblast cells exposed to GroPIns4P show significantly enhanced wound healing capability, indicating that GroPIns4P has a stimulatory role to activate fibroblast migration. GroPIns4P is produced by cPLA2 upon stimulation by diverse receptors, including the EGF receptor. Indeed, endogenously-produced GroPIns4P was shown to mediate the EGF-induced cell motility. CONCLUSIONS: This study identifies a so-far undescribed mechanism of Shp1/Src modulation that promotes cell motility and that is dependent on the cPLA2 metabolite GroPIns4P. We show that GroPIns4P is required for EGF-induced fibroblast migration and that it is part of a cPLA2/GroPIns4P/Shp1/Src cascade that might have broad implications for studies of immune-inflammatory response and cancer.
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Movimento Celular , Receptores ErbB/metabolismo , Fosfatos de Inositol/metabolismo , Fosfolipases A2/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Transdução de Sinais , Quinases da Família src/metabolismo , Animais , Sítios de Ligação , Fator de Crescimento Epidérmico/farmacologia , Camundongos , Células NIH 3T3 , Fosforilação , Ligação Proteica , Proteína Tirosina Fosfatase não Receptora Tipo 6/química , Células RAW 264.7 , Cicatrização , Domínios de Homologia de srcRESUMO
Inter-organelle signalling has essential roles in cell physiology encompassing cell metabolism, aging and temporal adaptation to external and internal perturbations. How such signalling coordinates different organelle functions within adaptive responses remains unknown. Membrane traffic is a fundamental process in which membrane fluxes need to be sensed for the adjustment of cellular requirements and homeostasis. Studying endoplasmic reticulum-to-Golgi trafficking, we found that Golgi-based, KDEL receptor-dependent signalling promotes lysosome repositioning to the perinuclear area, involving a complex process intertwined to autophagy, lipid-droplet turnover and Golgi-mediated secretion that engages the microtubule motor protein dynein-LRB1 and the autophagy cargo receptor p62/SQSTM1. This process, here named 'traffic-induced degradation response for secretion' (TIDeRS) discloses a cellular mechanism by which nutrient and membrane sensing machineries cooperate to sustain Golgi-dependent protein secretion.
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Autofagia , Gotículas Lipídicas/metabolismo , Lisossomos/metabolismo , Receptores de Peptídeos/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Núcleo Celular/ultraestrutura , Dineínas/metabolismo , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/ultraestrutura , Complexo de Golgi/metabolismo , Complexo de Golgi/ultraestrutura , Células HeLa , Humanos , Lisossomos/ultraestrutura , Microscopia Eletrônica de Transmissão , Microtúbulos/metabolismo , Microtúbulos/ultraestrutura , Transporte Proteico , Proteína Sequestossoma-1/metabolismo , Transdução de SinaisRESUMO
Ketoprofen L-lysine salt (KLS), is widely used due to its analgesic efficacy and tolerability, and L-lysine was reported to increase the solubility and the gastric tolerance of ketoprofen. In a recent report, L-lysine salification has been shown to exert a gastroprotective effect due to its specific ability to counteract the NSAIDs-induced oxidative stress and up-regulate gastroprotective proteins. In order to derive further insights into the safety and efficacy profile of KLS, in this study we additionally compared the effect of lysine and arginine, another amino acid counterion commonly used for NSAIDs salification, in control and in ethanol challenged human gastric mucosa model. KLS is widely used for the control of post-surgical pain and for the management of pain and fever in inflammatory conditions in children and adults. It is generally well tolerated in pediatric patients, and data from three studies in >900 children indicate that oral administration is well tolerated when administered for up to 3 weeks after surgery. Since only few studies have so far investigated the effect of ketoprofen on gastric mucosa maintenance and adaptive mechanisms, in the second part of the study we applied the cMap approach to compare ketoprofen-induced and ibuprofen-induced gene expression profiles in order to explore compound-specific targeted biological pathways. Among the several genes exclusively modulated by ketoprofen, our attention was particularly focused on genes involved in the maintenance of gastric mucosa barrier integrity (cell junctions, morphology, and viability). The hypothesis was further validated by Real-time PCR.
Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Arginina/farmacologia , Células Epiteliais/efeitos dos fármacos , Etanol/toxicidade , Mucosa Gástrica/efeitos dos fármacos , Ibuprofeno/farmacologia , Cetoprofeno/análogos & derivados , Lisina/análogos & derivados , Anti-Inflamatórios não Esteroides/toxicidade , Arginina/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Citoproteção , Combinação de Medicamentos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes/efeitos dos fármacos , Humanos , Ibuprofeno/toxicidade , Cetoprofeno/farmacologia , Cetoprofeno/toxicidade , Lisina/farmacologia , Lisina/toxicidade , Células MCF-7 , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Tempo , Transcriptoma/efeitos dos fármacosRESUMO
Following a clinical trial in which the Halsted mastectomy was compared to the less invasive quadrantectomy, no differences were reported in terms of local recurrence, disease-free or overall survival between the two. As a result, Umberto Veronesi was the first in the world to state that the radical mastectomy appeared to involve unnecessary mutilation in patients with breast cancer of less than 2 cm and no palpable axillary nodes. To date, the Veronesi quadrantectomy is routinely considered for breast cancer treatment. This brief review, which highlights the main advances over the last 50 years, is dedicated to Professor Umberto Veronesi.
RESUMO
The presence of a functional protein at the appropriate location in the cell is the result of the processes of transcription, translation, folding and trafficking to the correct destination. There are numerous diseases that are caused by protein misfolding, mainly due to mutations in the respective gene. The consequences of this misfolding may be that proteins effectively lose their function, either by being removed by the cellular quality control machinery or by accumulating at the incorrect intracellular or extracellular location. A number of mutations that lead to protein misfolding and affect trafficking to the final destination, e.g. Cystic fibrosis, Wilson's disease, and Progressive Familial Intrahepatic 1 cholestasis, result in proteins that retain partial function if their folding and trafficking is restored either by molecular or pharmacological means. In this review, we discuss several mutant proteins within this class of misfolding diseases and provide an update on the status of molecular and therapeutic developments and potential therapeutic strategies being developed to counter these diseases.
Assuntos
Transporte Proteico/genética , Proteínas/genética , Deficiências na Proteostase/genética , Colestase Intra-Hepática/genética , Colestase Intra-Hepática/patologia , Fibrose Cística/genética , Fibrose Cística/patologia , Degeneração Hepatolenticular/genética , Degeneração Hepatolenticular/patologia , Humanos , Proteínas/metabolismo , Deficiências na Proteostase/patologiaRESUMO
BACKGROUND AND PURPOSE: Whole breast radiotherapy (WBRT) is one of the possible reasons for the low rate of axillary recurrence after breast-conserving surgery (BCS). PATIENTS AND METHODS: We retrospectively collected data from 4,129 consecutive patients with breast cancer ⩽2cm and negative sentinel lymph node who underwent BCS between 1997 and 2007. We compared the risk of axillary lymph node recurrence between patients treated by WBRT (n=2939) and patients who received partial breast irradiation (PBI; n=1,190) performed by a single dose of electron intraoperative radiotherapy. RESULTS: Median tumour diameter was 1.1cm in both WBRT and PBI. Women who received WBRT were significantly younger and expressed significantly more multifocality, extensive in situ component, negative oestrogen receptor status and HER2 over-expression than women who received PBI. After a median follow-up of 8.3years, 37 and 28 axillary recurrences were observed in the WBRT and PBI arm, respectively, corresponding to a 10-year cumulative incidence of 1.3% and 4.0% (P<0.001). Multivariate analysis resulted in a hazard ratio of 0.30 (95% CI 0.17-0.51) in favour of WBRT. CONCLUSIONS: In this large series of women with T1 breast cancer and negative sentinel lymph node treated by BCS, WBRT lowered the risk of axillary recurrence by two thirds as compared to PBI.