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1.
Eur Radiol ; 34(4): 2500-2511, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37812294

RESUMO

OBJECTIVE: To determine prognostic value of bone marrow retention index (RI-bm) and bone marrow-to-liver ratio (BLR) measured on baseline dual-phase 18F-FDG PET/CT in a series of newly diagnosed patients with diffuse large B-cell lymphoma (DLBCL) treated homogeneously with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) chemotherapy. PATIENTS AND METHODS: This prospective study enrolled 135 patients with newly diagnosed DLBCL. All patients underwent dual-phase 18F-FDG PET/CT. The following PET parameters were calculated for both tumor and bone marrow: maximum standardized uptake value (SUVmax) at both time points (SUVmax early and SUVmax delayed), SUVmax increment (SUVinc), RI, and BLR. Patients were treated with R-CHOP regimen and response at end of treatment was assessed. RESULTS: The final analysis included 98 patients with complete remission. At a median follow-up of 22 months, 57 patients showed no relapse, 74 survived, and 24 died. The 2-year relapse-free survival (RFS) values for patients with higher and lower RI-bm were 20% and 65.1%, respectively (p < 0.001), and for patients with higher and lower BLR were 30.2% and 69.6%, respectively (p < 0.001). The 2-year overall survival (OS) values for patients with higher and lower RI-bm were 60% and 76.3%, respectively (p = 0.023), and for patients with higher and lower BLR were 57.3% and 78.6%, respectively (p = 0.035). Univariate analysis revealed that RI-bm and BLR were independent significant prognostic factors for both RFS and OS (hazard ratio [HR] = 4.02, p < 0.001, and HR = 3.23, p < 0.001, respectively) and (HR = 2.83, p = 0.030 and HR = 2.38, p = 0.041, respectively). CONCLUSION: Baseline RI-bm and BLR were strong independent prognostic factors in DLBCL patients. CLINICAL RELEVANCE STATEMENT: Bone marrow retention index (RI-bm) and bone marrow-to-liver ratio (BLR) could represent suitable and noninvasive positron emission tomography/computed tomography (PET/CT) parameters for predicting pretreatment risk in patients with newly diagnosed diffuse large B-cell lymphoma (DLBCL) who were treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) chemotherapy. KEY POINTS: • Bone marrow retention index (RI-bm) and bone marrow-to-liver ratio (BLR) are powerful prognostic variables in diffuse large B-cell lymphoma (DLBCL) patients. • High BLR and RI-bm are significantly associated with poor overall survival (OS) and relapse-free survival (RFS). • RI-bm and BLR represent suitable and noninvasive risk indicators in DLBCL patients.


Assuntos
Fluordesoxiglucose F18 , Linfoma Difuso de Grandes Células B , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Prognóstico , Medula Óssea/diagnóstico por imagem , Medula Óssea/patologia , Rituximab/uso terapêutico , Compostos Radiofarmacêuticos/uso terapêutico , Prednisona/uso terapêutico , Vincristina/uso terapêutico , Estudos Prospectivos , Recidiva Local de Neoplasia/patologia , Linfoma Difuso de Grandes Células B/diagnóstico por imagem , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/patologia , Doxorrubicina/uso terapêutico , Ciclofosfamida/uso terapêutico , Fígado/patologia
2.
FASEB J ; 36(10): e22545, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36094323

RESUMO

The kidneys are radiosensitive and dose-limiting organs for radiotherapy (RT) targeting abdominal and paraspinal tumors. Excessive radiation doses to the kidneys ultimately lead to radiation nephropathy. Our prior work unmasked a novel role for the lipid-modifying enzyme, sphingomyelin phosphodiesterase acid-like 3b (SMPDL3b), in regulating the response of renal podocytes to radiation injury. In this study, we investigated the role of SMPDL3b in DNA double-strand breaks (DSBs) repair in vitro and in vivo. We assessed the kinetics of DSBs recognition and repair along with the ATM pathway and nuclear sphingolipid metabolism in wild-type (WT) and SMPDL3b overexpressing (OE) human podocytes. We also assessed the extent of DNA damage repair in SMPDL3b knock-down (KD) human podocytes, and C57BL6 WT and podocyte-specific SMPDL3b-knock out (KO) mice after radiation injury. We found that SMPDL3b overexpression enhanced DSBs recognition and repair through modulating ATM nuclear shuttling. OE podocytes were protected against radiation-induced apoptosis by increasing the phosphorylation of p53 at serine 15 and attenuating subsequent caspase-3 cleavage. SMPDL3b overexpression prevented radiation-induced alterations in nuclear ceramide-1-phosphate (C1P) and ceramide levels. Interestingly, exogenous C1P pretreatment radiosensitized OE podocytes by delaying ATM nuclear foci formation and DSBs repair. On the other hand, SMPDL3b knock-down, in vitro and in vivo, induced a significant delay in DSBs repair. Additionally, increased activation of apoptosis was induced in podocytes of SMPDL3b-KO mice compared to WT mice at 24 h post-irradiation. Together, our results unravel a novel role for SMPDL3b in radiation-induced DNA damage response. The current work suggests that SMPDL3b modulates nuclear sphingolipid metabolism, ATM nuclear shuttling, and DSBs repair.


Assuntos
Podócitos , Lesões por Radiação , Animais , Ceramidas/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3 , Quebras de DNA de Cadeia Dupla , Humanos , Rim/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Podócitos/metabolismo , Lesões por Radiação/genética , Lesões por Radiação/metabolismo , Esfingomielina Fosfodiesterase/genética , Esfingomielina Fosfodiesterase/metabolismo
3.
Eur Radiol ; 33(2): 1286-1296, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35962816

RESUMO

OBJECTIVE: To assess the diagnostic accuracy and agreement of CT and MRI in terms of the Bosniak classification version 2019 (BCv2019). MATERIALS AND METHODS: A prospective multi-institutional study enrolled 63 patients with 67 complicated cystic renal masses (CRMs) discovered during ultrasound examination. All patients underwent CT and MRI scans and histopathology. Three radiologists independently assessed CRMs using BCv2019 and assigned Bosniak class to each CRM using CT and MRI. The final analysis included 60 histopathologically confirmed CRMs (41 were malignant and 19 were benign). RESULTS: Discordance between CT and MRI findings was noticed in 50% (30/60) CRMs when data were analyzed in terms of the Bosniak classes. Of these, 16 (53.3%) were malignant. Based on consensus reviewing, there was no difference in the sensitivity, specificity, and accuracy of the BCv2019 with MRI and BCv2019 with CT (87.8%; 95% CI = 73.8-95.9% versus 75.6%; 95% CI = 59.7-87.6%; p = 0.09, 84.2%; 95% CI = 60.4-96.6% versus 78.9%; 95% CI = 54.4-93.9%; p = 0.5, and 86.7%; 95% CI = 64.0-86.6% versus 76.7%; 95% CI = 75.4-94.1%; p = 0.1, respectively). The number and thickness of septa and the presence of enhanced nodules accounted for the majority of variations in Bosniak classes between CT and MRI. The inter-reader agreement (IRA) was substantial for determining the Bosniak class in CT and MRI (k = 0.66; 95% CI = 0.54-0.76, k = 0.62; 95% CI = 0.50-0.73, respectively). The inter-modality agreement of the BCv219 between CT and MRI was moderate (κ = 0.58). CONCLUSION: In terms of BCv2019, CT and MRI are comparable in the classification of CRMs with no significant difference in diagnostic accuracy and reliability. KEY POINTS: • There is no significant difference in the sensitivity, specificity, and accuracy of the BCv2019 with MRI and BCv2019 with CT. • The number of septa and their thickness and the presence of enhanced nodules accounted for the majority of variations in Bosniak classes between CT and MRI. • The inter-reader agreement was substantial for determining the Bosniak class in CT and MRI and the inter-modality agreement of the BCv219 between CT and MRI was moderate.


Assuntos
Doenças Renais Císticas , Neoplasias Renais , Humanos , Doenças Renais Císticas/diagnóstico , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X , Imageamento por Ressonância Magnética , Rim/patologia , Estudos Retrospectivos
4.
Ann Surg Oncol ; 29(1): 460-466, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34324113

RESUMO

PURPOSE: Post-mastectomy radiation therapy (PMRT) improves locoregional control and overall survival in patients with breast cancer. With the evolution of systemic therapy, the benefit of PMRT in patients with triple-negative disease requires further evaluation. PATIENTS AND METHODS: BEATRICE is a phase III randomized clinical trial that examined the efficacy of bevacizumab in patients with triple-negative breast cancer (TNBC). The current study is a retrospective analysis of data on patients enrolled and treated with mastectomy and systemic therapy. The primary endpoint was determining the effect of PMRT on locoregional recurrence rates (LRR). Hazard ratios were estimated using Cox regression, and LRR curves were generated by the Kaplan-Meier method. RESULTS: In total, 940 patients were included in our analysis, of whom 359 (38.2%) received PMRT while 581 (61.8%) did not. At median follow-up of 5 years, no significant difference in LRR was noted between the PMRT and no PMRT groups in node-negative patients (HR = 1.09). Patients with N1 disease had 5-year LRR-free survival of 96% for PMRT versus 91% for no PMRT (HR = 0.46). Most N2 patients received PMRT and had 5-year LRR-free survival of 76%. CONCLUSION: PMRT benefit in TNBC patients treated with modern systemic therapy is lower than historical reports. Delivery of PMRT in patients with N1 disease enrolled in the BEATRICE trial was not shown to improve local control. As this might be due to patient selection for PMRT, future randomized controlled trials are required to assess the role of PMRT in this patient population.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Mastectomia , Estudos Retrospectivos , Neoplasias de Mama Triplo Negativas/radioterapia
5.
BMC Cancer ; 22(1): 1296, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36503610

RESUMO

BACKGROUND: Intrahepatic cholangiocarcinoma (CCA) is amongst the most common primary liver tumors worldwide. CCA carries a bad prognosis prompting research to establish new treatment modalities other than surgery and the current chemotherapeutic regimens adopted. Hence, this trial explores a new therapeutic approach, to combine stereotactic body radiation therapy (SBRT) and immunotherapy (Nivolumab), and asses its clinical benefit and safety profile after induction chemotherapy in CCA. METHODOLOGY: This is a Phase II open-label, single-arm, multicenter study that investigates Nivolumab (PD-1 inhibitor) treatment at Day 1 followed by SBRT (30 Gy in 3 to 5 fractions) at Day 8, then monthly Nivolumab in 40 patients with non-resectable locally advanced, metastatic or recurrent intrahepatic or extrahepatic CCA. Eligible patients were those above 18 years of age with a pathologically and radiologically confirmed diagnosis of non-resectable locally advanced or metastatic or recurrent intrahepatic or extrahepatic CCA, following 4 cycles of cisplatin-based chemotherapy with an estimated life expectancy of more than 3 months, among other criteria. The primary endpoint is the progression free survival (PFS) rate at 8 months and disease control rate (DCR). The secondary endpoints are overall survival (OS), tumor response rate (TRR), duration of response, evaluation of biomarkers: CD3 + , CD4 + and CD8 + T cell infiltration, as well as any change in the PD-L1 expression through percutaneous core biopsy when compared with the baseline biopsy following 1 cycle of Nivolumab and SBRT. DISCUSSION: SRBT alone showed promising results in the literature by both inducing the immune system locally and having abscopal effects on distant metastases. Moreover, given the prevalence of PD-L1 in solid tumors, targeting it or its receptor has become the mainstay of novel immunotherapeutic drugs use. A combination of both has never been explored in the scope of CCA and that is the aim of this study. TRIAL REGISTRATION: ClinicalTrials.gov NCT04648319 , April 20, 2018.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Lactente , Nivolumabe/efeitos adversos , Antígeno B7-H1 , Quimioterapia de Indução , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/radioterapia , Neoplasias dos Ductos Biliares/radioterapia , Ductos Biliares Intra-Hepáticos
6.
Int J Cancer ; 149(8): 1520-1528, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34013530

RESUMO

Patients with metastatic breast cancer are usually considered incurable. Recent advances have resulted in significant improvements in survival for patients with metastatic breast cancer. Due to the lack of randomised trials and heterogeneous disease biology, treatment decisions for patients with oligometastatic breast cancer vary widely. Some patients are treated similar to those with widespread disease while others are treated more aggressively. We conducted a review of the evidence for treatment options in oligometastatic breast cancer and consulted ClinicalTrials.gov to explore currently accruing or studies in development aimed at investigating oligometastatic disease in breast cancer. Surgery to the primary tumour in patients with metastatic breast cancer has failed to show any advantage over systemic therapy. However, there may be a benefit in women with controlled systemic disease who are hormone receptor positive with bone-predominant metastasis. Stereotactic radiotherapy has gained increased interest in this setting due to its excellent efficacy and lower rates of associated toxicity. A significant challenge remains in identifying the patient population who would benefit from such an approach, and to do so, we need to understand the distinct biology of oligometastatic breast cancer. Unique miRNA expression and low levels of tumour infiltrating lymphocytes in the immune micro-environment have been described in tumour tissues in patients with oligometastatic breast cancer. There is ongoing research aimed to better characterise these tumours, thus, allowing the selection of patients who would truly benefit from multi-modality treatment in an attempt for long-term survival and cure.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Terapia Combinada , Feminino , Humanos , Metástase Neoplásica
7.
FASEB J ; 34(6): 7915-7926, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32293077

RESUMO

The intracellular molecular pathways involved in radiation-induced nephropathy are still poorly understood. Glomerular endothelial cells are key components of the structure and function of the glomerular filtration barrier but little is known about the mechanisms implicated in their injury and repair. The current study establishes the response of immortalized human glomerular endothelial cells (GEnC) to ionizing radiation (IR). We investigated the role of sphingolipids and the lipid-modifying enzyme sphingomyelin phosphodiesterase acid-like 3b (SMPDL3b) in radiation-induced GEnC damage. After delivering a single dose of radiation, long and very-long-chain ceramide species, and the expression levels of SMPDL3b were elevated. In contrast, levels of ceramide-1-phosphate (C1P) dropped in a time-dependent manner although mRNA and protein levels of ceramide kinase (CERK) remained stable. Treatment with C1P or knocking down SMPDL3b partially restored cell survival and conferred radioprotection. We also report a novel role for the NADPH oxidase enzymes (NOXs), namely NOX1, and NOX-derived reactive oxygen species (ROS) in radiation-induced GEnC damage. Subjecting cultured endothelial cells to radiation was associated with increased NOX activity and superoxide anion generation. Silencing NOX1 using NOX1-specific siRNA mitigated radiation-induced oxidative stress and cellular injury. In addition, we report a novel connection between NOX and SMPDL3b. Treatment with the NOX inhibitor, GKT, decreased radiation-induced cellular injury and restored SMPDL3b basal levels of expression. Our findings indicate the importance of SMPDL3b as a potential therapeutic target in radiation-induced kidney damage.


Assuntos
Células Endoteliais/metabolismo , Nefropatias/metabolismo , Glomérulos Renais/metabolismo , Esfingomielina Fosfodiesterase/metabolismo , Animais , Linhagem Celular , Humanos , Glomérulos Renais/efeitos da radiação , Masculino , Camundongos Endogâmicos C57BL , NADPH Oxidase 1/metabolismo , RNA Mensageiro/metabolismo , Radiação , Espécies Reativas de Oxigênio/metabolismo , Superóxidos/metabolismo
8.
BMC Cancer ; 20(1): 831, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32873251

RESUMO

BACKGROUND: Current standard practice for locally advanced rectal cancer (LARC) entails a multidisciplinary approach that includes preoperative chemoradiotherapy, followed by total mesorectal excision, and then adjuvant chemotherapy. The latter has been accompanied by low compliance rates and no survival benefit in phase III randomized trials, so the strategy of administering neoadjuvant, rather than adjuvant, chemotherapy has been adapted by many trials, with improvement in pathologic complete response. Induction chemotherapy with oxaliplatin has been shown to have increased efficacy in rectal cancer, while short-course radiation therapy with consolidation chemotherapy increased short-term overall survival rate and decreased toxicity levels, making it cheaper and more convenient than long-course radiation therapy. This led to recognition of total neoadjuvant therapy as a valid treatment approach in many guidelines despite limited available survival data. With the upregulation (PDL-1) expression in rectal tumors after radiotherapy and the increased use of in malignant melanoma, the novel approach of combining immunotherapy with chemotherapy after radiation may have a role in further increasing pCR and improving overall outcomes in rectal cancer. METHODS: The study is an open label single arm multi- center phase II trial. Forty-four recruited LARC patients will receive 5Gy x 5fractions of SCRT, followed by 6 cycles of mFOLFOX-6 plus avelumab, before TME is performed. The hypothesis is that the addition of avelumab to mFOLFOX-6, administered following SCRT, will improve pCR and overall outcomes. The primary outcome measure is the proportion of patients who achieve a pCR, defined as no viable tumor cells on the excised specimen. Secondary objectives are to evaluate 3-year progression-free survival, tumor response to treatment (tumor regression grades 0 & 1), density of tumor-infiltrating lymphocytes, correlation of baseline Immunoscore with pCR rates and changes in PD-L1 expression. DISCUSSION: Recent studies show an increase in PD-L1 expression and density of CD8+ TILs after CRT in rectal cancer patients, implying a potential role for combinatory strategies using PD-L1- and programmed-death- 1 inhibiting drugs. We aim through this study to evaluate pCR following SCRT, followed by mFOLFOX-6 with avelumab, and then TME procedure in patients with LARC. TRIAL REGISTRATION: Trial Registration Number and Date of Registration: ClinicalTrials.gov NCT03503630, April 20, 2018.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/radioterapia , Anticorpos Monoclonais Humanizados/administração & dosagem , Antineoplásicos Imunológicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Imunoterapia/métodos , Terapia Neoadjuvante/métodos , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/radioterapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ensaios Clínicos Fase II como Assunto , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Compostos Organoplatínicos/administração & dosagem , Intervalo Livre de Progressão , Estudos Prospectivos , Adulto Jovem
9.
FASEB J ; 33(12): 14051-14066, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31661292

RESUMO

Cancer was recently annexed to diabetic complications. Furthermore, recent studies suggest that cancer can increase the risk of diabetes. Consequently, diabetes and cancer share many risk factors, but the cellular and molecular pathways correlating diabetes and colon and rectal cancer (CRC) remain far from understood. In this study, we assess the effect of hyperglycemia on cancer cell aggressiveness in human colon epithelial adenocarcinoma cells in vitro and in an experimental animal model of CRC. Our results show that Nox (NADPH oxidase enzyme) 4-induced reactive oxygen species (ROS) production is deregulated in both diabetes and CRC. This is paralleled by inactivation of the AMPK and activation of the mammalian target of rapamycin (mTOR) C1 signaling pathways, resulting in 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) accumulation, induction of DNA damage, and exacerbation of cancer cell aggressiveness, thus contributing to the genomic instability and predisposition to increased tumorigenesis in the diabetic milieu. Pharmacologic activation of AMPK, inhibition of mTORC1, or blockade of Nox4 reduce ROS production, restore the homeostatic signaling of 8-oxoguanine DNA glycosylase/8-oxodG, and lessen the progression of CRC malignancy in a diabetic milieu. Taken together, our results identify the AMPK/mTORC1/Nox4 signaling axis as a molecular switch correlating diabetes and CRC. Modulating this pathway may be a strategic target of therapeutic potential aimed at reversing or slowing the progression of CRC in patients with or without diabetes.-Mroueh, F. M., Noureldein, M., Zeidan, Y. H., Boutary, S., Irani, S. A. M., Eid, S., Haddad, M., Barakat, R., Harb, F., Costantine, J., Kanj, R., Sauleau, E.-A., Ouhtit, A., Azar, S. T., Eid, A. H., Eid, A. A. Unmasking the interplay between mTOR and Nox4: novel insights into the mechanism connecting diabetes and cancer.


Assuntos
NADPH Oxidase 4/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Animais , Antibióticos Antineoplásicos/farmacologia , Glicemia , Células CACO-2 , Dano ao DNA , Diabetes Mellitus Experimental , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HT29 , Humanos , Hipoglicemiantes/farmacologia , Masculino , Metformina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , NADPH Oxidase 4/genética , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/genética , Regulação para Cima
10.
Bioorg Chem ; 102: 104089, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32717691

RESUMO

Novel symmetric molecules, bearing a benzidine prolinamide core, two terminal carbamate caps of variable sizes and nature, including natural and unnatural amino acids were developed. Several terminal N-carbamate substituents of the core structure, ranging from linear methyl, ethyl and butyl groups to branching isobutyl group; and an aromatic substituent were also synthesized. Series 1 has hydrophobic AA residues, namely S and R phenylglycine and a terminal carbamate capping group, whereas Series 2 bears sulphur containing amino acids, specifically S and R methionine and the natural R methylcysteine. The novel compounds were tested for their inhibitory activity (EC50) and their cytotoxicity (CC50), using an HCV 1b (Con1) reporter replicon cell line. Compound 4 with the unnatural capping residue, bearing d-Phenylglycine amino acid residue and N-isobutyloxycarbonyl capping group, was the most active within the two series, with EC50 = 0.0067 nM. Moreover, it showed high SI50 > 14788524 and was not cytotoxic at the highest tested concentration (100 µΜ), indicating its safety profile. Compound 4 also inhibited HCV genotypes 2a, 3a and 4a. Compared to the clinically approved NS5A inhibitor Daclatasvir, compound 4 shows higher activity against genotypes 1b and 3a, as well as improved safety profile.


Assuntos
Aminoácidos/farmacologia , Antivirais/farmacologia , Benzidinas/farmacologia , Carbamatos/farmacologia , Hepacivirus/efeitos dos fármacos , Aminoácidos/química , Antivirais/síntese química , Antivirais/química , Benzidinas/síntese química , Benzidinas/química , Carbamatos/química , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , RNA Viral/efeitos dos fármacos , Estereoisomerismo , Relação Estrutura-Atividade
11.
Int J Mol Sci ; 21(12)2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32599736

RESUMO

Although once considered as structural components of eukaryotic biological membranes, research in the past few decades hints at a major role of bioactive sphingolipids in mediating an array of physiological processes including cell survival, proliferation, inflammation, senescence, and death. A large body of evidence points to a fundamental role for the sphingolipid metabolic pathway in modulating the DNA damage response (DDR). The interplay between these two elements of cell signaling determines cell fate when cells are exposed to metabolic stress or ionizing radiation among other genotoxic agents. In this review, we aim to dissect the mediators of the DDR and how these interact with the different sphingolipid metabolites to mount various cellular responses.


Assuntos
Dano ao DNA , Radiação Ionizante , Transdução de Sinais , Esfingolipídeos/metabolismo , Estresse Fisiológico , Animais , Diferenciação Celular , Sobrevivência Celular , Reparo do DNA , Humanos
12.
Tech Coloproctol ; 23(2): 151-159, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30783863

RESUMO

BACKGROUND: This study aimed to determine if the nature of circumferential resection margin (CRM) involvement, either by tumour or lymph nodes, had an impact upon local recurrence and survival in rectal cancer. METHODS: A retrospective analysis of a prospectively collected database was performed. Consecutive patients with stage I-III rectal cancer having curative surgery were included. All specimens were analysed by a single histopathologist. Statistical analysis was performed using chi-squared test and Kaplan-Meier. RESULTS: Of 265 patients, 29 (11%) had a positive CRM. Compared to patients with a negative CRM, a positive margin due to tumour was associated with a higher 5-year cumulative incidence of local recurrence (43.7% versus 8.8%, p = 0.001) and distant metastases (62% versus 13.6%, p = 0.001) with poorer 5-year cancer-specific survival (32% versus 87.8%, p = 0.001). Although patients with margin positivity due to lymph nodes had a higher rate of distant metastases (41.3% versus 13.6%, p = 0.004) and poorer 5-year cancer-specific survival (59.3% versus 87.8%, p = 0.038), the rate of local recurrence was comparable to that of patients with negative margins (8.3% versus 8.8%, p = 0.694). CONCLUSIONS: Our findings suggest that the nature of CRM involvement may be important in determining prognosis in rectal cancer. Local recurrence is higher only when there is tumour present at the margin. Lymph node involvement of the margin confers similar risk of local recurrence to patients with CRM-negative, node-positive disease. These results need further evaluation in multicentre, prospective studies.


Assuntos
Linfonodos/patologia , Margens de Excisão , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia , Idoso , Bases de Dados Factuais , Feminino , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Reto/patologia , Reto/cirurgia , Estudos Retrospectivos
13.
FASEB J ; 31(2): 771-780, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27836988

RESUMO

The molecular mechanisms responsible for the development of proteinuria and glomerulosclerosis in radiation nephropathy remain largely unknown. Podocytes are increasingly recognized as key players in the pathogenesis of proteinuria in primary and secondary glomerular disorders. The lipid-modulating enzyme sphingomyelin phosphodiesterase acid-like 3B (SMPDL3b) is a key determinant of podocyte injury and a known off target of the anti-CD20 antibody rituximab (RTX). The current study investigates the role of sphingolipids in radiation-induced podocytopathy. After a single dose of radiation (8 Gy), several ceramide species were significantly elevated. In particular, C16:00, C24:00, and C24:1 ceramides were the most abundant ceramide species detected. These changes were paralleled by a time-dependent drop in SMPDL3b protein, sphingosine, and sphingosine-1-phosphate levels. Interestingly, SMPDL3b-overexpressing podocytes had higher basal levels of sphingosine-1-phosphate and maintained basal ceramide levels after irradiation. Morphologically, irradiated podocytes demonstrated loss of filopodia and remodeling of cortical actin. Furthermore, the actin binding protein ezrin relocated from the plasma membrane to the cytosol as early as 2 h after radiation. In contrast, SMPDL3b overexpressing podocytes were protected from radiation-induced cytoskeletal remodeling. Treatment with RTX before radiation exposure partially protected podocytes from SMPDL3b loss, cytoskeletal remodeling, and caspase 3 cleavage. Our results demonstrate that radiation injury induces early cytoskeletal remodeling, down-regulation of SMPDL3b, and elevation of cellular ceramide levels. Overexpression of SMPDL3b and pretreatment with RTX confer a radioprotective effect in cultured podocytes. These findings indicate a potential role for SMPDL3b and RTX in radiation-induced podocytopathy.-Ahmad, A., Mitrofanova, A., Bielawski, J., Yang, Y., Marples, B., Fornoni, A., Zeidan, Y. H. Sphingomyelinase-like phosphodiesterase 3b mediates radiation-induced damage of renal podocytes.


Assuntos
Nucleotídeo Cíclico Fosfodiesterase do Tipo 3/metabolismo , Podócitos/metabolismo , Podócitos/efeitos da radiação , Esfingomielina Fosfodiesterase/metabolismo , Animais , Ceramidas/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3/genética , Regulação para Baixo , Regulação Enzimológica da Expressão Gênica , Humanos , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Rituximab/administração & dosagem , Rituximab/farmacologia , Esfingomielina Fosfodiesterase/genética
14.
Ann Dermatol Venereol ; 145(12): 785-789, 2018 Dec.
Artigo em Francês | MEDLINE | ID: mdl-30389201

RESUMO

INTRODUCTION: Griscelli syndrome (GS) is a rare autosomal-recessive genetic disease characterized by hypopigmentation of skin and hair. We report a case of GS type 3 with late diagnosis. OBSERVATION: A 31-year-old female patient had presented depigmentation of the hair and eyebrows as well as diffuse skin hypopigmentation during childhood. Microscopic analysis of a hair shaft revealed irregularly distributed clumps of melanin. DNA sequencing showed a homozygous C103T (R35W) transition in exon 1 of MLPH, confirming Griscelli syndrome type 3. DISCUSSION: Three clinical phenotypes of GS have been described based on the underlying genetic defect. GS type 1 and 2 are associated respectively with a central nervous system dysfunction and an immune defect. GS type 3 is an isolated cutaneous form. Diagnosis is confirmed on microscopic examination of hair shafts. 15 cases of GS type 3 have been reported: 9 in males and 6 in females. Mean age at diagnosis is around 12 years. Nine of the reported patients were of Arab origin, four of Turkish origin, and one of Indian origin. R35W mutation was described in 9 cases and E98X and R35Q mutations were each found in one case. CONCLUSION: GS should be suspected in patients presenting gray silvery hair, particularly when these patients are of Arab or Turkish origin.


Assuntos
Piebaldismo/genética , Transtornos da Pigmentação/genética , Complicações na Gravidez/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Adulto , Argélia/etnologia , Consanguinidade , Diagnóstico Tardio , Diagnóstico Diferencial , Éxons/genética , Feminino , Cabelo/química , Cabelo/patologia , Cor de Cabelo/genética , Humanos , Melaninas/análise , Mutação de Sentido Incorreto , Fenótipo , Piebaldismo/patologia , Transtornos da Pigmentação/patologia , Mutação Puntual , Gravidez , Complicações na Gravidez/patologia
15.
Ann Dermatol Venereol ; 145(4): 278-287, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29463465

RESUMO

INTRODUCTION: Syphilis is a sexually transmitted disease that can affect numerous organs in its secondary or tertiary stages. We describe a case of secondary syphilis with pulmonary involvement and we present a literature review. PATIENTS AND METHODS: A 69-year-old male patient was admitted to hospital for dyspnoea and extended papular exanthema with palmoplantar involvement. The serological test for syphilis was positive. Ocular examination showed bilateral papillitis and retinal haemorrhage. Chest radiography revealed an interstitial alveolar infiltrate predominantly in the upper lobes, mild pleural effusion and hilar adenopathy. These infiltrates were slightly hypermetabolic on PET scan suggesting inflammatory or infectious origin. Treatment with intravenous penicillin G was effective on cutaneous, ocular and pulmonary manifestations. DISCUSSION: Lung involvement in secondary syphilis is poorly known and rarely described. We found 27 cases of pulmonary syphilis reported in English and the main European languages since 1967. Mean age at diagnosis was 46 years with clear male predominance (89%). HIV co-infection was declared in 5 cases. Treponema pallidum was found in 6 patients using PCR on bronchoalveolar lavage (BAL) (3 patients) or on a lung biopsy (1 patient), immunohistochemistry (IHC) on BAL (1 patient) and Giemsa staining on a pleural fluid sample (1 patient). Chest X-rays may show unilateral or bilateral infiltrates or nodules with or without pleural effusion or hilar adenopathy. Sub-pleural involvement is frequent and penicillin is the treatment of choice. CONCLUSION: Pulmonary syphilitic involvement should be suspected where pulmonary symptoms or radiological changes occur in secondary syphilis. IHC, special staining or PCR on BAL, pleural fluid or lung tissue are useful for the identification of spirochetes.


Assuntos
Antibacterianos/administração & dosagem , Doenças Pulmonares Intersticiais/diagnóstico , Penicilina G/administração & dosagem , Derrame Pleural/tratamento farmacológico , Sífilis/complicações , Sífilis/tratamento farmacológico , Administração Intravenosa , Idoso , Dispneia/microbiologia , Exantema/microbiologia , Humanos , Doenças Pulmonares Intersticiais/tratamento farmacológico , Doenças Pulmonares Intersticiais/microbiologia , Masculino , Derrame Pleural/diagnóstico , Derrame Pleural/microbiologia , Hemorragia Retiniana/microbiologia , Sífilis/diagnóstico , Sorodiagnóstico da Sífilis , Resultado do Tratamento
17.
Int J Mol Sci ; 18(12)2017 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-29186855

RESUMO

Sphingolipids, long thought to be passive components of biological membranes with merely a structural role, have proved throughout the past decade to be major players in the pathogenesis of many human diseases. The study and characterization of several genetic disorders like Fabry's and Tay Sachs, where sphingolipid metabolism is disrupted, leading to a systemic array of clinical symptoms, have indeed helped elucidate and appreciate the importance of sphingolipids and their metabolites as active signaling molecules. In addition to being involved in dynamic cellular processes like apoptosis, senescence and differentiation, sphingolipids are implicated in critical physiological functions such as immune responses and pathophysiological conditions like inflammation and insulin resistance. Interestingly, the kidneys are among the most sensitive organ systems to sphingolipid alterations, rendering these molecules and the enzymes involved in their metabolism, promising therapeutic targets for numerous nephropathic complications that stand behind podocyte injury and renal failure.


Assuntos
Doença de Fabry/metabolismo , Nefropatias/metabolismo , Podócitos/metabolismo , Esfingolipídeos/metabolismo , Doença de Tay-Sachs/metabolismo , Animais , Doença de Fabry/genética , Doença de Fabry/terapia , Humanos , Nefropatias/genética , Nefropatias/terapia , Doença de Tay-Sachs/genética , Doença de Tay-Sachs/terapia , Pesquisa Translacional Biomédica
18.
J Surg Res ; 200(2): 648-54, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26541684

RESUMO

BACKGROUND: Pediatric facial fractures, although uncommon, have a significant impact on public health and the US economy by the coexistence of other injuries and developmental deformities. Violence is one of the most frequent mechanisms leading to facial fracture. Teaching hospitals, while educating future medical professionals, have been linked to greater resource utilization in differing scenarios. This study was designed to compare the differences in patient characteristics and outcomes between teaching and non-teaching hospitals for violence-related pediatric facial fractures. METHODS: Using the 2000-2009 Kids' Inpatient Database, 3881 patients younger than 18 years were identified with facial fracture and external cause of injury code for assault, fight, or abuse. Patients admitted at teaching hospitals were compared to those admitted at non-teaching hospitals in terms of demographics, injuries, and outcomes. RESULTS: Overall, 76.2% of patients had been treated at teaching hospitals. Compared to those treated at non-teaching hospitals, these patients were more likely to be younger, non-white, covered by Medicaid, from lower income zip codes, and have thoracic injuries; but mortality rate was not significantly different. After adjusting for potential confounders, teaching status of the hospital was not found as a predictor of either longer lengths of stay (LOS) or charges. CONCLUSIONS: There is an insignificant difference between LOS and charges at teaching and non-teaching hospitals after controlling for patient demographics. This suggests that the longer LOS observed at teaching hospitals is related to these institutions being more often involved in the care of underserved populations and patients with more severe injuries.


Assuntos
Preços Hospitalares/estatística & dados numéricos , Hospitais de Ensino/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Traumatismos Maxilofaciais/epidemiologia , Fraturas Cranianas/epidemiologia , Violência/estatística & dados numéricos , Adolescente , Criança , Maus-Tratos Infantis/estatística & dados numéricos , Pré-Escolar , Bases de Dados Factuais , Feminino , Hospitais de Ensino/economia , Humanos , Lactente , Tempo de Internação/economia , Masculino , Traumatismos Maxilofaciais/economia , Traumatismos Maxilofaciais/etiologia , Traumatismos Maxilofaciais/terapia , Estudos Retrospectivos , Fraturas Cranianas/economia , Fraturas Cranianas/etiologia , Fraturas Cranianas/terapia , Resultado do Tratamento , Estados Unidos/epidemiologia
19.
Foot (Edinb) ; 59: 102090, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38537500

RESUMO

BACKGROUND: Non insertional Achilles tendinopathy [AT] is a degenerative condition that is prevalent in runners. 30% have no preceding history and many runners do not develop AT. Overuse, pronation, and compromised blood supply are hypothesised as causal. The exact precipitant is still unknown. The link between medial arch instability and AT has not been made. The purpose of this study was to investigate the association between spring ligament (SL) laxity and first ray (FRI) instability, and the presence of (AT). METHODS: Ethical approval was obtained. Patients were identified from hospital databases for unilateral AT, allowing the opposite unaffected foot to be used as an internal control. SL laxity was measured using the lateral translation score and FRI was measured using a modified digital Klauemeter. Ultrasound was used to assess the tendoachilles [TA] in affected vs unaffected legs. RESULTS: 17 patients were recruited with a mean age of 55.6 and mean body mass index (BMI) of 33.3. The average symptom duration was 3.62 years. There were 12 left feet and 5 right feet. There was no statistical difference in dorsiflexion angles for the TA or the gastrocnemius. All Beighton scores < 5. Lateral translation scores, FRI scores and TA thickness was significantly greater in AT feet [p < 0.05]. More affected feet had Tibialis posterior tendon pain (TP) [p < 0.05]. CONCLUSIONS: Feet with AT exhibit higher lateral translation scores and greater FRI compared to healthy feet, and combined with previous literature evidence, suggests alteration of the subtalar axis alters force moments that may lead to an intrinsic overload of the TA, when the foot enters a "zone of conflict". Medial arch instability, in particular SL laxity and FRI, may contribute to the development of non-insertional AT and treatment of this with early arch support may prevent progressive degeneration.


Assuntos
Tendão do Calcâneo , Instabilidade Articular , Tendinopatia , Humanos , Tendinopatia/fisiopatologia , Tendinopatia/diagnóstico por imagem , Tendão do Calcâneo/diagnóstico por imagem , Tendão do Calcâneo/fisiopatologia , Feminino , Masculino , Pessoa de Meia-Idade , Instabilidade Articular/fisiopatologia , Adulto , Idoso , Corrida/fisiologia , Ultrassonografia
20.
Cureus ; 16(5): e60979, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38910761

RESUMO

BACKGROUND: Current guidelines recommend shifting physician-led care (PLC) for type 2 diabetes mellitus (T2DM) to more effective multidisciplinary health care (MHC). However, few researchers have studied its real-life implementation in Saudi Arabia. Therefore, we aimed to assess the implementation and compare the outcomes of an MDC diabetes management program (DMP) among T2DM patients to a PLC at a general hospital after one year of follow-up in a real-world practice setting. METHODS: We conducted this comparative patient files review study by analyzing medical records of all T2DM patients at two private care centers. Both were compared for their effectiveness in achieving two outcomes: the glycated hemoglobin (HbA1c) <7% and low-density lipoprotein-cholesterol (LDL-c) <70 mg/dl at the end of the first year. Additionally, we assessed the implementation of the DMP. RESULTS: Eight hundred thirty-four medical records were reviewed, 537 from DMP, and 279 from the PLC center. The personal health coordination was almost complete (97.8%) in the DMP, but the implementation was incomplete regarding nutrition (65.7%), dental exam (64.8%), and foot care (58.3%). Both care groups were matched for age (p = 0.056), gender (p = 0.085), duration of diabetes (p = 0.217), and basal glycemic control (p = 0.171). The DMP showed a significant net decrease in HbA1c (-0.5 [IQR 1.47%] vs -0.2 [IQR 3.05%], p = 0.0001) and LDL-c (-10 [IQR 50] vs -5 [IQR 60.5] mg/dl, p = 0.004) compared to PLC. A higher percentage of patients achieved glycemic control in the DMP than in the PLC (49.4% vs 38.7%, p = 0.038). However, both programs demonstrated similar outcomes in lipid control (28.7% vs. 30%, p = 0.695). CONCLUSION: Despite some gaps in implementation, one year of DMP showed better glycemic control among T2DM patients compared to PLC. Both programs were comparable in terms of lipid control. Further studies identifying the gaps in care implementation could improve sustainability, future replication, and generalizability of similar programs to other healthcare systems in Saudi Arabia.

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