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1.
Blood ; 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39093982

RESUMO

B-cell acute lymphoblastic leukemia (B-ALL) is the most common pediatric cancer, with long-term overall survival rates of ~85%. However, B-ALL harboring rearrangements of the MLL gene (also known as KMT2A), referred to as MLLr B-ALL, is common in infants and is associated with poor 5-year survival (<30%), frequent relapses, and refractoriness to glucocorticoids (GCs). GCs are an essential part of the treatment backbone for B-ALL and GC resistance is a major clinical predictor of poor outcome. Elucidating the mechanisms of GC resistance in MLLr B-ALL is, therefore, critical to guide therapeutic strategies that deepen the response after induction therapy. Neuron-glial antigen-2 (NG2) expression is a hallmark of MLLr B-ALL and is minimally expressed in healthy hematopoietic cells. We recently reported that NG2 expression is associated with poor prognosis and that anti-NG2 immunotherapy strongly reduces/delays relapse in MLLr B-ALL xenograft models. Despite its contribution to MLLr B-ALL pathogenesis and its diagnostic utility, the role of NG2 in MLLr-mediated leukemogenesis/chemoresistance remains elusive. Here we show that NG2 is an epigenetically regulated direct target gene of the leukemic MLL-AF4 fusion protein. NG2 negatively regulates the expression of the GC receptor NR3C1 and confers GC resistance to MLLr B-ALL cells in vitro and in vivo. Mechanistically, NG2 interacts with FLT3 to render ligand-independent activation of FLT3 signaling (a hallmark of MLLr B-ALL) and downregulation of NR3C1 via AP-1-mediated trans-repression. Collectively, our study elucidates the role of NG2 in GC resistance in MLLr B-ALL through FLT3/AP-1-mediated downregulation of NR3C1, providing novel therapeutic avenues for MLLr B-ALL.

2.
J Pers Med ; 14(8)2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39202029

RESUMO

BACKGROUND: This study evaluated the clinical outcomes of applying a 68 Gy EQD2(α/ß=3) dose constraint to the most exposed 2 cm3 area of the vagina in post-operative endometrial cancer patients treated with vaginal-cuff brachytherapy after external beam irradiation and the impact of vaginal dilator use on late vaginal complications. MATERIAL AND METHODS: We analyzed 131 patients treated with vaginal-cuff brachytherapy after external beam irradiation. Group-1 (65 patients) received one fraction of 7 Gy, and Group-2 (66 patients) received one fraction of between 5.5 and 7.0 Gy after applying a 68 Gy EQD2(α/ß=3) dose constraint. Vaginal-cuff relapse, late toxicity, clinical target volume, vaginal dilator use, D90, and EQD2(α/ß=3) at 2 cm3 of the most exposed part of the clinical target volume were evaluated. Descriptive analysis, the chi-squared test, Student's t-test, and the Cox proportional and Kaplan-Meier models were used for the statistical analysis. RESULTS: With a median follow-up of 60 months, the vaginal-cuff relapse rate was 1/131 (0.8%). Late vaginal complications appeared in 36/65 (55.4%) Group-1 patients and 17/66 (25.8%) Group-2 patients (p = 0.003). Multivariate analysis showed that belonging to Group-1 and vaginal dilator use of <9 months were independent prognostic factors of late vaginal complications with hazard ratios of 1.99 (p = 0.021) and 3.07 (p = 0.010), respectively. CONCLUSIONS: A 68 Gy EQD2(α/ß=3) constraint at 2 cm3 of clinical target volume and vaginal dilator use of ≥9 months were independent prognostic factors, having protective effects on late vaginal complications.

3.
J Pers Med ; 14(3)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38541063

RESUMO

(1) Background: High dose gradients and manual steps in brachytherapy treatment procedures can lead to dose errors which make the use of in vivo dosimetry (IVD) highly recommended for verifying brachytherapy treatments. A new procedure was presented to obtain a calibration factor which allows fast and robust calibration of plastic scintillation detector (PSD) probes for the geometry of a compact phantom using Monte Carlo simulations. Additionally, characterization of PSD energy, angular, and temperature dependences was performed. (2) Methods: PENELOPE/PenEasy code was used to obtain the calibration factor. To characterize the energy dependence of the PSD, the signal was measured at different radial and transversal distances. The sensitivity to the angular position was characterized in axial and azimuthal planes. (3) Results: The calibration factor obtained allows for an absorbed dose to water determination in full scatter conditions from ionization measured in a mini polymethylmethacrylate (PMMA) phantom. The energy dependence of the PSD along the radial distances obtained was (2.3 ± 2.1)% (k = 1). The azimuthal angular dependence measured was (2.6 ± 3.4)% (k = 1). The PSD response decreased by (0.19 ± 0.02)%/°C with increasing detector probe temperature. (4) Conclusions: The energy, angular, and temperature dependence of a PSD is compatible with IVD.

4.
FEBS J ; 291(11): 2423-2448, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38451841

RESUMO

Oxidation of histone H3 at lysine 4 (H3K4ox) is catalyzed by lysyl oxidase homolog 2 (LOXL2). This histone modification is enriched in heterochromatin in triple-negative breast cancer (TNBC) cells and has been linked to the maintenance of compacted chromatin. However, the molecular mechanism underlying this maintenance is still unknown. Here, we show that LOXL2 interacts with RuvB-Like 1 (RUVBL1), RuvB-Like 2 (RUVBL2), Actin-like protein 6A (ACTL6A), and DNA methyltransferase 1associated protein 1 (DMAP1), a complex involved in the incorporation of the histone variant H2A.Z. Our experiments indicate that this interaction and the active form of RUVBL2 are required to maintain LOXL2-dependent chromatin compaction. Genome-wide experiments showed that H2A.Z, RUVBL2, and H3K4ox colocalize in heterochromatin regions. In the absence of LOXL2 or RUVBL2, global levels of the heterochromatin histone mark H3K9me3 were strongly reduced, and the ATAC-seq signal in the H3K9me3 regions was increased. Finally, we observed that the interplay between these series of events is required to maintain H3K4ox-enriched heterochromatin regions, which in turn is key for maintaining the oncogenic properties of the TNBC cell line tested (MDA-MB-231).


Assuntos
Aminoácido Oxirredutases , Heterocromatina , Histonas , Neoplasias de Mama Triplo Negativas , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo , Humanos , Aminoácido Oxirredutases/genética , Aminoácido Oxirredutases/metabolismo , Histonas/metabolismo , Histonas/genética , Feminino , Heterocromatina/metabolismo , Heterocromatina/genética , Linhagem Celular Tumoral , Cromatina/metabolismo , Cromatina/genética , Regulação Neoplásica da Expressão Gênica , DNA Helicases/genética , DNA Helicases/metabolismo
5.
Clin Transl Oncol ; 26(7): 1623-1629, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38267659

RESUMO

INTRODUCTION: Intraoperative electron radiotherapy (IOERT) is a technique aiming to deliver radiotherapy during oncological surgery. In breast IOERT, the applicator and shielding disc placement are correlated with organs at risk (OAR) irradiation, in vivo verification of these parameters is scarcely reported. The aim of our study is to report and analyze possible causes of the misalignment using radiochromic films and compare our results to others reported in the bibliography. METHODS: From November 2019 to April 2023, in vivo verifications were performed for 33 patients. IOERT was performed using a LIAC 10 MeV (Sordina, Italy) electron accelerator. We attached a radiochromic film to the upper side of the polytetrafluoroethylene cover of the shielding disc. The percentage of the irradiation area outside the disc was recorded and various parameters (applicator angulations, prescription depth, tumor location and breast size) were analyzed to find possible correlations. RESULTS: For 29 patients, 20 Gy were prescribed while 10 Gy were prescribed to 4 patients. The average irradiated area outside the disc was 19% (0-56%) corresponding to a surface of 4.5 cm2 (0-17.4 cm2). The applicator of 5 cm was used for most of the patients. The mean prescription depth was 1.4 cm (0.5-2.5 cm). We found no correlation between the analyzed parameters and misalignment. CONCLUSION: This study confirms the presence and magnitude of the misalignments. We strongly recommend in vivo verifications as a quality check during IOERT procedures. The misalignment has no correlation with tumor localization parameters, so the solution could be based on technical improvements of the applicator.


Assuntos
Neoplasias da Mama , Elétrons , Humanos , Feminino , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Elétrons/uso terapêutico , Controle de Qualidade , Órgãos em Risco/efeitos da radiação , Dosagem Radioterapêutica , Cuidados Intraoperatórios/métodos , Pessoa de Meia-Idade , Aceleradores de Partículas , Idoso , Planejamento da Radioterapia Assistida por Computador/métodos , Adulto
6.
Clin Transl Oncol ; 26(2): 456-460, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37548869

RESUMO

PURPOSE: Brachytherapy (BT) has been used for many years for disease control in tumours of the head and neck area (H&N). It is currently performed with high dose rate (HDR) or pulsed dose rate (PDR), but its use has been reduced due to the implementation of new non-invasive external beam radiotherapy techniques such as intensity modulation (IMRT) and volumetric modulated arc therapy (VMAT) and the improvement of surgical techniques. METHODS: The Spanish Brachytherapy Group (GEB) has carried out a survey to find out the number of centres in Spain that continue to use BT in H&N and its indications and expectations for the future. RESULTS: The results were presented at the XX GEB Consensus Meeting held on October 21, 2022, in Valencia (Spain) and it was confirmed that, although there are fewer and fewer centres that use BT in H&N, there are still units with extensive experience in this technique that should be positioned as referral centres. CONCLUSION: It is necessary to carry out continuous work with other specialities involved, such as H&N surgeons, and other radiation oncologists, to improve the training of residents, both oncologists and medical physicists.


Assuntos
Braquiterapia , Radioterapia de Intensidade Modulada , Humanos , Braquiterapia/métodos , Espanha , Radioterapia de Intensidade Modulada/métodos , Pescoço , Planejamento da Radioterapia Assistida por Computador/métodos , Dosagem Radioterapêutica
7.
Biochim Biophys Acta Rev Cancer ; 1879(1): 189037, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38043804

RESUMO

Snail1 transcriptional factor plays a key role in the control of epithelial to mesenchymal transition, a process that remodels tumor cells increasing their invasion and chemo-resistance as well as reprograms their metabolism and provides stemness properties. During this transition, Snail1 acts as a transcriptional repressor and, as growing evidences have demonstrated, also as a direct activator of mesenchymal genes. In this review, I describe the different proteins that interact with Snail1 and are responsible for these two different functions on gene expression; I focus on the transcriptional factors that associate to Snail1 in their target promoters, both activated and repressed. I also present working models for Snail1 action both as repressor and activator and raise some issues that still need to be investigated.


Assuntos
Transição Epitelial-Mesenquimal , Fatores de Transcrição , Humanos , Fatores de Transcrição da Família Snail/genética , Transição Epitelial-Mesenquimal/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica , Regiões Promotoras Genéticas
8.
Breast Cancer Res ; 25(1): 143, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37964360

RESUMO

BACKGROUND: As in most solid cancers, the emergence of cells with oncogenic mutations in the mammary epithelium alters the tissue homeostasis. Some soluble factors, such as TGFß, potently modify the behavior of healthy stromal cells. A subpopulation of cancer-associated fibroblasts expressing a TGFß target, the SNAIL1 transcription factor, display myofibroblastic abilities that rearrange the stromal architecture. Breast tumors with the presence of SNAIL1 in the stromal compartment, and with aligned extracellular fiber, are associated with poor survival prognoses. METHODS: We used deep RNA sequencing and biochemical techniques to study alternative splicing and human tumor databases to test for associations (correlation t-test) between SNAIL1 and fibronectin isoforms. Three-dimensional extracellular matrices generated from fibroblasts were used to study the mechanical properties and actions of the extracellular matrices on tumor cell and fibroblast behaviors. A metastatic mouse model of breast cancer was used to test the action of fibronectin isoforms on lung metastasis. RESULTS: In silico studies showed that SNAIL1 correlates with the expression of the extra domain A (EDA)-containing (EDA+) fibronectin in advanced human breast cancer and other types of epithelial cancers. In TGFß-activated fibroblasts, alternative splicing of fibronectin as well as of 500 other genes was modified by eliminating SNAIL1. Biochemical analyses demonstrated that SNAIL1 favors the inclusion of the EDA exon by modulating the activity of the SRSF1 splicing factor. Similar to Snai1 knockout fibroblasts, EDA- fibronectin fibroblasts produce an extracellular matrix  that does not sustain TGFß-induced fiber organization, rigidity, fibroblast activation, or tumor cell invasion. The presence of EDA+ fibronectin changes the action of metalloproteinases on fibronectin fibers. Critically, in an mouse orthotopic breast cancer model, the absence of the fibronectin EDA domain completely prevents lung metastasis. CONCLUSIONS: Our results support the requirement of EDA+ fibronectin in the generation of a metastasis permissive stromal architecture in breast cancers and its molecular control by SNAIL1. From a pharmacological point of view, specifically blocking EDA+ fibronectin deposition could be included in studies to reduce the formation of a pro-metastatic environment.


Assuntos
Neoplasias da Mama , Neoplasias Pulmonares , Animais , Feminino , Humanos , Camundongos , Processamento Alternativo , Neoplasias da Mama/genética , Fibronectinas/genética , Fibronectinas/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Fatores de Processamento de Serina-Arginina/genética , Fatores de Processamento de Serina-Arginina/metabolismo , Fator de Crescimento Transformador beta/metabolismo
9.
Radiother Oncol ; 189: 109909, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37699447

RESUMO

PURPOSE: To compare two vaginal brachytherapy (VBT) schedules in postoperative endometrial carcinoma (PEC) patients considering vaginal-cuff relapses (VCR), late toxicities, dosimetry analysis and vaginal dilator use. MATERIAL AND METHODS: 110 PEC patients were treated with exclusive high-dose-rate VBT using two schedules. Group-1:44-patients received 6 Gy×3fractions (September-2011-April-2014); Group-2:66-patients were treated with 7.5 Gy×2fractions with a dose limit of equivalent total doses in 2-Gy fr (EQD2(α/ß=3)) of 68 Gy in the most exposed 2 cm3 of clinical target volume (CTV) (July-2015-November-2021). The dose was prescribed at 5 mm from the applicator surface. Were evaluated the overall radiation dose delivered to 90% of the CTV (D90), the CTV receiving 100% of the prescription dose (V100) and the EQD2(α/ß=3) received in the most exposed 2 cm3 to dose in CTV. Late toxicity was prospectively assessed using RTOG scores for bladder and rectum and objective LENT-SOMA criteria for late vaginal toxicity (LVT). STATISTICS: Descriptive analysis, Chi-square, Student's t-tests and Kaplan and Meier method. RESULTS: The median follow-up was 60 months (15.9-60). There were no VCR or late toxicities in bladder or rectum. LVT ≥ G1 appeared in 26/44 (59.1%) in Group-1 and 25/66 (37.9%) in Group-2. The mean EQD2(α/ß=3) received by the most exposed 2 cm3 of CTV was 63.7 Gy ± 10.0 in Group-1 and 60.5 Gy ± 3.8 in Group-2 (p = 0.063). There were no differences in adherence to vaginal dilator use ≥9 months, overall D90 and V100. CONCLUSION: Considering the lack of vaginal relapses and similar LVT over time, 7.5 Gy×2fractions seem more efficient in terms of patient comfort, workload, and cost. This is the first study using dosimetry parameters to compare effectivity of schedules. Larger series are needed to confirm the present results.


Assuntos
Braquiterapia , Neoplasias do Endométrio , Feminino , Humanos , Braquiterapia/efeitos adversos , Braquiterapia/métodos , Recidiva Local de Neoplasia/patologia , Vagina/patologia , Neoplasias do Endométrio/radioterapia , Neoplasias do Endométrio/cirurgia , Recidiva
10.
Mol Oncol ; 17(8): 1492-1513, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37199012

RESUMO

Snail1 is a transcriptional factor required for cancer-associated fibroblast (CAF) activation, and mainly detected in CAFs in human tumors. In the mouse mammary tumor virus-polyoma middle tumor-antigen (MMTV-PyMT) model of murine mammary gland tumors, Snai1 gene deletion, besides increasing tumor-free lifespan, altered macrophage differentiation, with fewer expressing low levels of MHC class II. Snail1 was not expressed in macrophages, and in vitro polarization with interleukin-4 (IL4) or interferon-γ (IFNγ) was not altered by Snai1 gene depletion. We verified that CAF activation modified polarization of naïve bone-marrow-derived macrophages (BMDMΦs). When BMDMΦs were incubated with Snail1-expressing (active) CAFs or with conditioned medium derived from these cells, they exhibited a lower cytotoxic capability than when incubated with Snail1-deleted (inactive) CAFs. Gene expression analysis of BMDMΦs polarized by conditioned medium from wild-type or Snai1-deleted CAFs revealed that active CAFs differentially stimulated a complex combination of genes comprising genes that are normally induced by IL4, downregulated by IFNγ, or not altered during the two canonical differentiations. Levels of RNAs relating to this CAF-induced alternative polarization were sensitive to inhibitors of factors specifically released by active CAFs, such as prostaglandin E2 and TGFß. Finally, CAF-polarized macrophages promoted the activation of the immunosuppressive regulatory T cells (T-regs). Our results imply that an active CAF-rich tumor microenvironment induces the polarization of macrophages to an immunosuppressive phenotype, preventing the macrophage cytotoxic activity on tumor cells and enhancing the activation of T-reg cells.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias , Humanos , Camundongos , Animais , Fibroblastos Associados a Câncer/metabolismo , Interleucina-4/farmacologia , Meios de Cultivo Condicionados/metabolismo , Diferenciação Celular , Macrófagos/metabolismo , Microambiente Tumoral , Linhagem Celular Tumoral , Neoplasias/patologia
11.
Clin Transl Oncol ; 25(6): 1748-1755, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36752959

RESUMO

PURPOSE: Analyse the impact of different prognostic factors on G2-late vaginal complications after vaginal brachytherapy (VBT) ± external beam radiotherapy (EBRT) in postoperative endometrial cancer (PEC). METHODS: One hundred and twenty-six PEC patients treated with VBT ± EBRT were retrospectively analysed considering age, body mass index, applicator diameter, clinical target volume (CTV), use of dilators, chemotherapy and EQD2(α/ß=3) at the most exposed 2 cm3 of the CTV as prognostic factors for vaginal complications. Late vaginal complications were evaluated using objective LENT-SOMA criteria. STATISTICS: descriptive analysis, Chi-square, Fisher and Student tests were applied. Univariate and multivariate analyses were performed with the Baptista-Pike exact method and multiple logistic regression. RESULTS: Mean age was 65 years (SD ± 10), and median follow-up was 66 months (8-104). 19/126 patients (15%) showed G2-late vaginal complications, and 107/126 (85%) G0-G1. Univariate analysis showed: CTV ≤ 9 cm3 (p = 0.036), use of dilators < 9 months (p = 0.015), and total ≥ 68 Gy EQD2 received by 2 cm3 of CTV (p = 0.039) were associated with G2-late vaginal toxicity. Multivariate analysis showed the use of dilators < 9 months as an independent prognostic factor for G2-late vaginal toxicity (p = 0.043, OR 8.59, CI 1.59-159.9). CONCLUSION: The use of dilators < 9 months in VBT ± EBRT for PEC was an independent prognostic factor for G2-late vaginal toxicity. The use of vaginal dilators ≥ 9 months requires further analysis in studies evaluating late vaginal toxicity.


Assuntos
Braquiterapia , Neoplasias do Endométrio , Feminino , Humanos , Braquiterapia/efeitos adversos , Braquiterapia/métodos , Estudos Retrospectivos , Prognóstico , Vagina/patologia , Neoplasias do Endométrio/radioterapia , Neoplasias do Endométrio/cirurgia , Neoplasias do Endométrio/patologia , Estadiamento de Neoplasias
12.
EMBO Rep ; 24(4): e54895, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36704936

RESUMO

Colon tumors of the mesenchymal subtype have the lowest overall survival. Snail1 is essential for the acquisition of this phenotype, characterized by increased tumor stemness and invasion, and high resistance to chemotherapy. Here, we find that Snail1 expression in colon tumor cells is dependent on an autocrine noncanonical Wnt pathway. Accordingly, depletion of Ror2, the co-receptor for noncanonical Wnts such as Wnt5a, potently decreases Snail1 expression. Wnt5a, Ror2, and Snail1 participate in a self-stimulatory feedback loop since Wnt5a increases its own synthesis in a Ror2- and Snail1-dependent fashion. This Wnt5a/Ror2/Snail1 axis controls tumor invasion, chemoresistance, and formation of tumor spheres. It also stimulates TGFß synthesis; consequently, tumor cells expressing Snail1 are more efficient in activating cancer-associated fibroblasts than the corresponding controls. Ror2 downmodulation or inhibition of the Wnt5a pathway decreases Snail1 expression in primary colon tumor cells and their ability to form tumors and liver metastases. Finally, the expression of SNAI1, ROR2, and WNT5A correlates in human colon and other tumors. These results identify inhibition of the noncanonical Wnt pathway as a putative colon tumor therapy.


Assuntos
Neoplasias do Colo , Via de Sinalização Wnt , Humanos , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Fibroblastos
13.
Rep Pract Oncol Radiother ; 27(5): 905-913, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36523812

RESUMO

Background: Salvage surgery is considered an option for isolated recurrences of retroperitoneal and pelvic tumors, in patients who have undergone previous radiotherapy. In order to increase local control intra operative electron radiation therapy (IOERT) can be used in these patients to administer additional radiation dose. We evaluated the outcomes and adverse effects in patients with retroperitoneal sarcoma and gynecologic tumors after salvage surgery and IOERT. Materials and methods: Twenty patients were retrospectively analyzed. Twenty-three IOERT treatments were performed after surgery. Six (30%) were sarcoma and 14 (70%) were gynecological carcinoma. Administered dose depended on previous dose received with external beam radiotherapy (EBRT) and proximity to critical structures. The toxicities were scored using the Common Terminology Criteria for Adverse Events version 4.0. Results: The median age of the patients was 51 years (range 34-70). After a median follow-up of 32 months (range 1-68), in the sarcoma group the local control rate was 66.6%; while in the gynecological group the local control rate was 64.3%. In relation to late toxicity, one patient had a Grade 2 vesicovaginal fistula, and one patient presented Grade 4 enterocolitis and enteric intestinal fistula. Conclusions: IOERT could have a role in the treatment of retroperitoneal sarcomas in primary tumors after EBRT, as it may suggest a benefit in local control or recurrences after surgical resection in those at high risk of microscopic residual disease. The addition of IOERT to salvage resection for isolated recurrence of gynecologic cancers suggest favorable local control in cases with concern for residual microscopic disease.

14.
J Pers Med ; 12(6)2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35743696

RESUMO

(1) Background: In brachytherapy, there are still many manual procedures that can cause adverse events which can be detected with in vivo dosimetry systems. Plastic scintillator dosimeters (PSD) have interesting properties to achieve this objective such as real-time reading, linearity, repeatability, and small size to fit inside brachytherapy catheters. The purpose of this study was to evaluate the performance of a PSD in postoperative endometrial brachytherapy in terms of source dwell time accuracy. (2) Methods: Measurements were carried out in a PMMA phantom to characterise the PSD. Patient measurements in 121 dwell positions were analysed to obtain the differences between planned and measured dwell times. (3) Results: The repeatability test showed a relative standard deviation below 1% for the measured dwell times. The relative standard deviation of the PSD sensitivity with accumulated absorbed dose was lower than 1.2%. The equipment operated linearly in total counts with respect to absorbed dose and also in count rate versus absorbed dose rate. The mean (standard deviation) of the absolute differences between planned and measured dwell times in patient treatments was 0.0 (0.2) seconds. (4) Conclusions: The PSD system is useful as a quality assurance tool for brachytherapy treatments.

16.
Theranostics ; 11(16): 7671-7684, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335957

RESUMO

Snail1 is a transcriptional factor required for epithelial to mesenchymal transition and activation of cancer-associated fibroblasts (CAF). Apart from that, tumor endothelial cells also express Snail1. Here, we have unraveled the role of Snail1 in this tissue in a tumorigenic context. Methods: We generated transgenic mice with an endothelial-specific and inducible Snail1 depletion. This murine line was crossed with MMTV-PyMT mice that develop mammary gland tumors and the consequence of Snail1 depletion in the endothelium were investigated. We also interfere Snail1 expression in cultured endothelial cells. Results: Specific Snail1 depletion in the endothelium of adult mice does not promote an overt phenotype; however, it delays the formation of mammary gland tumors in MMTV-PyMT mice. These effects are associated to the inability of Snail1-deficient endothelial cells to undergo angiogenesis and to enhance CAF activation in a paracrine manner. Moreover, tumors generated in mice with endothelium-specific Snail1 depletion are less advanced and show a papillary phenotype. Similar changes on onset and tumor morphology are observed by pretreatment of MMTV-PyMT mice with the angiogenic inhibitor Bevacizumab. Human breast papillary carcinomas exhibit a lower angiogenesis and present lower staining of Snail1, both in endothelial and stromal cells, compared with other breast neoplasms. Furthermore, human breast tumors datasets show a strong correlation between Snail1 expression and high angiogenesis. Conclusion: These findings show a novel role for Snail1 in endothelial cell activation and demonstrate that these cells impact not only on angiogenesis, but also on tumor onset and phenotype.


Assuntos
Neoplasias da Mama/genética , Fatores de Transcrição da Família Snail/metabolismo , Animais , Neoplasias da Mama/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Carcinogênese/patologia , Linhagem Celular Tumoral , Células Endoteliais/metabolismo , Transição Epitelial-Mesenquimal/genética , Transição Epitelial-Mesenquimal/fisiologia , Feminino , Fibroblastos/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neovascularização Patológica/patologia , Fatores de Transcrição da Família Snail/genética , Fatores de Transcrição/metabolismo
17.
Nat Commun ; 12(1): 3932, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34168145

RESUMO

Chemical descriptors encode the physicochemical and structural properties of small molecules, and they are at the core of chemoinformatics. The broad release of bioactivity data has prompted enriched representations of compounds, reaching beyond chemical structures and capturing their known biological properties. Unfortunately, bioactivity descriptors are not available for most small molecules, which limits their applicability to a few thousand well characterized compounds. Here we present a collection of deep neural networks able to infer bioactivity signatures for any compound of interest, even when little or no experimental information is available for them. Our signaturizers relate to bioactivities of 25 different types (including target profiles, cellular response and clinical outcomes) and can be used as drop-in replacements for chemical descriptors in day-to-day chemoinformatics tasks. Indeed, we illustrate how inferred bioactivity signatures are useful to navigate the chemical space in a biologically relevant manner, unveiling higher-order organization in natural product collections, and to enrich mostly uncharacterized chemical libraries for activity against the drug-orphan target Snail1. Moreover, we implement a battery of signature-activity relationship (SigAR) models and show a substantial improvement in performance, with respect to chemistry-based classifiers, across a series of biophysics and physiology activity prediction benchmarks.


Assuntos
Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Relação Estrutura-Atividade , Linhagem Celular Tumoral , Bases de Dados de Produtos Farmacêuticos , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Fatores de Transcrição da Família Snail/antagonistas & inibidores , Fatores de Transcrição da Família Snail/genética , Fatores de Transcrição da Família Snail/metabolismo
18.
Med Clin (Barc) ; 157(11): 513-523, 2021 12 10.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33183766

RESUMO

OBJECTIVE: To know the vascular age (VA) of a sample of general population included in the RICARTO study. PATIENTS AND METHOD: Epidemiological study of the general population aged ≥18 from the Health Area of Toledo, based on the health card database. VA was calculated from the absolute cardiovascular risk (CVR) estimated with the Framingham and SCORE equations (type2 diabetes increased CVR in SCORE 2-fold in men and 4-fold in women). Patients with cardiovascular or renal disease were excluded. An ANCOVA analysis was conducted to adjust and compare the mean of VA by age and sex. RESULTS: 1,496 subjects (53.54% women) were analyzed. Mean (SD) age was 48.77 (14.89) years old and. Mean VA was 51.37 (19.13) with Framingham equation and 57.09 (17.63) years old with SCORE equation. VA was significantly higher in men, low education level, arterial hypertension, dyslipidemia, hypertriglyceridemia, diabetes mellitus, abdominal obesity, general obesity, smoking and in individuals with 5CVR factors vs none (P<.001 in all). Higher differences (Cohen's D >0.5) were found in non-diabetic vs diabetic people (1.58 Framingham; 2.44 SCORE), normotensive vs hypertensive subjects (1.64 Framingham; 1.19 SCORE), and non-dyslipidemia vs presence of dyslipidemia (0.95 Framingham; 0.66 SCORE). CONCLUSIONS: VA of our sample is two and a half years older than chronological one with Framingham equation and more than eight years with SCORE equation. Control of CVR factors is the key to get a VA closer to real and to obtain a better cardiovascular health in the population.


Assuntos
Doenças Cardiovasculares , Hipertensão , Adolescente , Pressão Sanguínea , Doenças Cardiovasculares/epidemiologia , Feminino , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco , Espanha/epidemiologia
19.
Cancer Res ; 81(2): 438-451, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33229340

RESUMO

Tumors are complex tissues composed of transformed epithelial cells as well as cancer-activated fibroblasts (CAF) that facilitate epithelial tumor cell invasion. We show here that CAFs and other mesenchymal cells rely much more on glutamine than epithelial tumor cells; consequently, they are more sensitive to inhibition of glutaminase. Glutamine dependence drove CAF migration toward this amino acid when cultured in low glutamine conditions. CAFs also invaded a Matrigel matrix following a glutamine concentration gradient and enhanced the invasion of tumor cells when both cells were cocultured. Accordingly, glutamine directed invasion of xenografted tumors in immunocompromised mice. Stimulation of glutamine-driven epithelial tumor invasion by fibroblasts required previous CAF activation, which involved the TGFß/Snail1 signaling axis. CAFs moving toward Gln presented a polarized Akt2 distribution that was modulated by the Gln-dependent activity of TRAF6 and p62 in the migrating front, and depletion of these proteins prevented Akt2 polarization and Gln-driven CAF invasion. Our results demonstrate that glutamine deprivation promotes CAF migration and invasion, which in turn facilitates the movement of tumor epithelial cells toward nutrient-rich territories. These results provide a novel molecular mechanism for how metabolic stress enhances invasion and metastasis. SIGNIFICANCE: Cancer-associated fibroblasts migrate and invade toward free glutamine and facilitate invasion of tumor epithelial cells, accounting for their movement away from the hostile conditions of the tumor towards nutrient-rich adjacent tissues. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/81/2/438/F1.large.jpg.


Assuntos
Neoplasias da Mama/patologia , Fibroblastos Associados a Câncer/patologia , Movimento Celular , Transição Epitelial-Mesenquimal , Glutamina/farmacologia , Neoplasias Epiteliais e Glandulares/patologia , Animais , Apoptose , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Fibroblastos Associados a Câncer/efeitos dos fármacos , Fibroblastos Associados a Câncer/metabolismo , Proliferação de Células , Feminino , Humanos , Camundongos , Camundongos Nus , Neoplasias Epiteliais e Glandulares/tratamento farmacológico , Neoplasias Epiteliais e Glandulares/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Cancers (Basel) ; 12(10)2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33092163

RESUMO

Background: To evaluate whether EQD2(α/ß = 3Gy) at 2 cm3 of the most exposed area of the vagina is related to late vaginal toxicity in postoperative endometrial cancer (PEC) patients (p) treated with exclusive brachytherapy (BT). Methods: From 2014 to 2017, 43p were included in this study. BT was administered: 3-fractions of 6Gy in 37p and 2-fractions of 7.5Gy in 6p. The dose was prescribed at a depth of 5 mm from the applicator surface with dose-point optimization based on distance. The active treatment length was 2.5 cm. CTV-D90 and the dose to the most exposed 2 cm3 of the vagina was calculated for each patient. Late toxicity of the bladder and rectum was assessed using Radiation Therapy Oncology Group (RTOG) criteria, and vaginal toxicity by objective Late Effects Normal Tissue Task Force (LENT)-Subjective, Objective, Management, Analytic (SOMA) (LENT-SOMA) criteria. Statistics: frequency tables, mean, median, range, standard deviation, and box plot. Results: The median follow-up was 51 months (12-68). 20 p (46.5%) and 2 p (4.7%) developed G1 and G2 vaginal complications, respectively. Only 1/2 p-G2 receiving EQD2(α/ß = 3Gy) at 2 cm3 >68Gy presented vaginal shortening and 18/20 p-G1 received doses < 68Gy. Conclusions: PECp receiving exclusive brachytherapy with doses < 68Gy EQD2(α/ß = 3Gy) at 2 cm2 of the vagina presented only G0-G1 vaginal toxicity, except for one with bleeding telangiectasias. Larger prospective studies are necessary to confirm the present results.

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