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1.
Bone ; 171: 116744, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36958543

RESUMO

BACKGROUND: Fibrous dysplasia/McCune-Albright syndrome (FD/MAS) is a rare genetic bone disease caused by a somatic mutation in the GNAS gene. Currently used bone turnover markers (BTMs) do not correlate with the clinical picture and are not useful to predict or monitor therapy success. This study assessed the correlation of RANKL, OPG, RANKL/OPG ratio, IL-6 and sclerostin with the classic BTMs alkaline phosphatase (ALP), procollagen type 1 propeptide (P1NP) and beta crosslaps (CTX), with pain, skeletal burden score (SBS) and response to bisphosphonate or denosumab treatment. METHODS: Ninety-six serum samples of adult patients >18 years of age with any subtype of FD/MAS were included from the biobank facility of the Leiden University Medical Center, Center for Bone Quality between 2015 and 2021. Standard laboratory assessments were assessed as part of usual care. The concentrations of potential biomarkers RANKL, OPG, sclerostin, IL-6 were analyzed. Data on FD/MAS subtype, age, pain, treatment history and treatment response were retrieved from the electronic patient files. Baseline characteristics were summarized by descriptive statistics. Correlations of the concentrations of the potential biomarkers with classic bone turnover markers, SBS and pain scores were cross-sectionally assessed by Spearman rank order correlation. Correction for multiple testing was performed by Benjamini and Hochberg False Discovery Rate. A sensitivity analyses was performed by excluding patients with SBS below 15 and patients using antiresorptive medication at the time of blood withdrawal or within the wash-out period. In patients treated with bisphosphonates or denosumab after blood withdrawal, pre-treatment concentrations were compared in patients with and without therapy response by Mann Whitney U test. RESULTS: The median age of the patients was 41.2 (Q1-Q3 25.9-52.2) years, 62.5 % was female. Median SBS was 2.5 (Q1-Q3 0.5-7.8). RANKL level correlated weakly with ALP (Spearman rho 0.309, p = 0.004, n = 84), but not with P1NP or CTX. The RANKL/OPG ratio, OPG, IL-6 and sclerostin did not correlate with ALP, P1NP or CTX. None of the potential biomarkers correlated with SBS or pain. Results of the sensitivity analyses were comparable. Pre-treatment biomarker levels were similar in patients with and without improvement in pain scores following bisphosphonate therapy. Pre-treatment RANKL and sclerostin were comparable between patients with and without improvement in pain scores after denosumab therapy. Pre-treatment IL-6 level and the RANKL/OPG ratio seemed to be higher in patients with response to denosumab (IL-6: median 0.64 (Q1-Q3 0.53-0.74) pg/mL, n = 6, RANKL/OPG: median 0.062 (Q1-Q3 0.016-0.331), n = 5) compared to patients without response (IL-6: median 0.35 (0.20-0.54) pg/mL, n = 5, RANKL/OPG: 0.027 (0.024-0.046), n = 4). Pre-treatment IL-6 correlated with the improvement in maximum pain scores (rho 0.962, p < 0.001, n = 9) and average pain scores (rho 0.895, p = 0.001, n = 9) reported during denosumab therapy. CONCLUSION: Increased concentrations of RANKL, IL-6, sclerostin and of the RANKL/OPG ratio do not indicate severity of FD/MAS, as no correlation was observed of these potential biomarkers with the classic BTMs and SBS. Biomarker levels did not correlate with pain and had no value in predicting bisphosphonate treatment response. These biomarkers are not superior over the currently used methods of assessing ALP, P1NP and CTX or evaluating SBS to establish disease extent or activity and provide no reliable results. Yet, possibly pre-treatment IL-6 and the RANKL/OPG ratio may have some predictive value for clinical response to denosumab. Therefore, studies investigating disease activity and treatment response should include lesional imaging and patient-reported outcome measures.


Assuntos
Displasia Fibrosa Óssea , Displasia Fibrosa Poliostótica , Adulto , Humanos , Feminino , Displasia Fibrosa Poliostótica/tratamento farmacológico , Interleucina-6 , Denosumab/uso terapêutico , Difosfonatos/uso terapêutico , Biomarcadores , Dor
2.
Bone ; 169: 116679, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36652988

RESUMO

BACKGROUND: In fibrous dysplasia/McCune-Albright syndrome (FD/MAS), mosaic mutations in the GNAS gene lead to locally abnormal bone turnover. Additionally, patients with FD/MAS, particularly with thoracic lesions, have an increased risk for breast cancer. Development and progression of breast cancer has been associated with expression of Receptor Activator of NF-κB ligand (RANKL) in mammary tissue, and due to the GNAS mutation, RANKL is systemically increased in patients with FD/MAS. Yet it is unknown whether breast cancer in FD/MAS is also dependent on RANKL. We hypothesized that the GNAS mutation might induce RANKL overproduction and an oncogenic niche in mammary tissue, and examined RANKL expression in breast cancer tissue of patients with FD/MAS compared to controls. METHODS: Nine patients with FD/MAS and breast cancer were included and clinical data were retrieved. Patients were matched to controls with breast cancer without FD/MAS based on age and tumor type. Three pregnant breast cancer patients were included as positive controls. Immunohistochemical detection of RANKL was performed on formalin-fixed paraffin-embedded breast cancer specimens. Staining intensity was classified as weak, moderate or intense. The area of positive RANKL staining divided by the total ductal-lobular area was assessed (positive area percentage, PAP). Number of patients with RANKL expression was compared between FD/MAS and control group by chi-square (χ2) test, the PAP by Mann-Whitney U test (MWU). RESULTS: RANKL expression was observed in 3 patients with FD/MAS (38 %), mainly in healthy tissue, and none of the control patients (χ2p = 0.055). The FD/MAS group demonstrated considerably more intense staining than the control group, comparable to positive controls. The median PAP was 0.64 % (range 0.14-2.04 %) in the 3 FD/MAS patients with RANKL expression, 0.01 % (Q1-Q3: 0.0003-0.514 %) in the entire FD/MAS group, 0.006 % (Q1-Q3: 0.001-0.012 %) in the control group (MWU = 0.574), and 0.19 % (0.08-0.32 %) in the pregnant patients. All patients with FD/MAS and RANKL expression had thoracic bone lesions, but no correlation was observed between RANKL expression and presence of the GNAS mutation or FD disease burden. CONCLUSIONS: The triad of a higher number of patients, higher positive area percentage and stronger intensity in the FD/MAS compared to the control group indicates that RANKL may be upregulated in mammary tissue in a subset of patients with FD/MAS, which may explain the increased risk for breast cancer, although the clinical significance remains unclear. Further research is needed to establish risk profiles for the development of RANKL-positive breast cancer and to improve early screening and treatment.


Assuntos
Neoplasias da Mama , Displasia Fibrosa Óssea , Displasia Fibrosa Poliostótica , Humanos , Feminino , Ligantes , Mutação , NF-kappa B
3.
Calcif Tissue Int ; 110(3): 334-340, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34854944

RESUMO

Mazabraud's syndrome (MZB) is a rare condition in which fibrous dysplasia of bone/the McCune-Albright syndrome (FD/MAS) co-exists with intramuscular myxomas. Both FD and the myxomas harbor the GNAS-mutation. Recent studies have shown that extraskeletal, GNAS-related features are associated with a more severe phenotype of FD/MAS. However, patients with MZB are often only seen by orthopedic surgeons. We therefore evaluated MZB patients seen in tertiary referral centers from the Netherlands (LUMC), USA (National Institutes of Health) and France (INSERM UMR 1033 (Lyos), Hôpital Edouard Herriot). All FD/MAS patients known in these centers with an additional diagnosis of a myxoma were included. Demographic information and data on disease extent and extraskeletal manifestations of FD/MAS such as precocious puberty (PP) or café-au-lait patches (CAL) were retrieved from patient's medical records. Thirty MZB patients were included: 20 women (67%) and 10 men (33%). Patients received a diagnosis of MZB (median 42 years, range 16-19) significantly later than the diagnosis of FD/MAS (median 30 years, range 0-60), p < 0.01. Twenty-six patients were diagnosed with polyostotic disease (87%). In 97% the myxoma was located near the skeletal FD lesion. The combination of MZB and MAS was made in 13 patients in whom PP (n = 7), CAL (n = 7), GH-excess (n = 3) and hyperthyroidism (n = 3) were present. Other extraskeletal features were (multinodular) goiter (n = 2) and thyroid cysts (n = 1). Furthermore, in this cohort of patients with MZB several (pre-)malignant tumors were observed; ductal carcinoma in situ of the breast in 3 patients (10%), breast cancer in 1 patient (3.3%), intra pancreatic mucinous neoplasms in 3 patients (10%) and liver adenomas in 2 patients (6.6%). A total of 47% of patients with MZB had an additional extraskeletal feature such as an endocrinopathy. In MZB, 87% of patients suffer from polyostotic FD, 43% of patients have extraskeletal GNAS-features such as an hyperfunctioning endocrinopathy and 30% (pre-)malignant tumors. We therefore advocate that MZB patients should undergo a complete screening and long-term follow-up for extent of bone disease, but also extraskeletal GNAS features of FD/MAS.


Assuntos
Doenças do Sistema Endócrino , Displasia Fibrosa Óssea , Displasia Fibrosa Poliostótica , Mixoma , Puberdade Precoce , Manchas Café com Leite/complicações , Manchas Café com Leite/genética , Feminino , Displasia Fibrosa Óssea/complicações , Displasia Fibrosa Poliostótica/complicações , Displasia Fibrosa Poliostótica/diagnóstico , Displasia Fibrosa Poliostótica/genética , Humanos , Masculino , Mixoma/complicações , Puberdade Precoce/complicações , Puberdade Precoce/genética , Síndrome
4.
Calcif Tissue Int ; 108(3): 346-353, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33226445

RESUMO

Malignant transformation of fibrous dysplasia lesions has been reported in patients with fibrous dysplasia/McCune-Albright syndrome (FD/MAS). Recently, we have observed an increased risk for breast cancer. In this study, the prevalence of skeletal and extraskeletal malignancies in patients with FD/MAS in the Netherlands was assessed by analyzing data from our cohort of FD/MAS patients, the Dutch Pathology Registry (PALGA), and the Netherlands Cancer Registry (NCR). We extracted data on sex, age at diagnosis of FD/MAS, type of FD/MAS, type of malignancy, and age at diagnosis of malignancy and histology of bone and malignant tissue when available, including GNAS-mutation analysis from patients' medical records. Standardized Morbidity Ratios (SMRs) with 95% confidence intervals were calculated. Twelve malignancies were identified in the LUMC FD/MAS cohort and 100 in the PALGA cohort. In this cohort, SMR was increased for osteosarcoma (19.7, 95% CI 3.5-48.9), cervical cancer (4.93, 95%CI 1.7-8.2), thyroid cancer (3.71, 95% CI 1.1-7.8), prostate cancer (3.08, 95% CI 1.8-4.6), and melanoma (2.01, 95%CI 1.2-3.1). SMRs for pancreatic cancer or hepatocellular carcinoma could not be calculated due to low numbers. The small number of malignancies identified in our FD/MAS cohort precluded the calculation of SMRs for our cohort specifically. Our findings show that patients with FD/MAS appear to have an increased risk for osteosarcoma, cervical, thyroid, and prostate cancer and melanoma. However, these data should be interpreted with caution, as true incidence rates of the identified malignancies may be influenced by the inclusion of only patients with histologically confirmed FD/MAS. The etiology of this increased risk for malignancies still needs to be elucidated.


Assuntos
Displasia Fibrosa Poliostótica , Neoplasias , Displasia Fibrosa Poliostótica/epidemiologia , Humanos , Neoplasias/epidemiologia , Países Baixos , Prevalência , Sistema de Registros
6.
Calcif Tissue Int ; 103(5): 469-475, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29948062

RESUMO

Impairments in quality of life (QoL) have been reported in patients with fibrous dysplasia (FD). Here, we examine coping strategies in FD and assess whether these coping strategies are associated with QoL and disease severity. Ninety-two patients (66% females) filled out the Utrecht Coping List (UCL), Short Form-36, and the Brief Pain Inventory (BPI). Coping strategies of patients with FD were compared with reference data from a random sample of Dutch women and patients with chronic pain. Compared to healthy adults, patients expressed more emotions (p < 0.01). Compared to patients with chronic pain, patients with FD used more active coping strategies (p < 0.001), and sought more distraction (p = 0.01) and more social support (p < 0.001). Using more passive coping strategies was associated with more impairment in social function, physical role, mental health, vitality (all p < 0.001), and general health (p < 0.01). Using more avoidant coping strategies was associated with worse mental health and less vitality (both p < 0.01). More expression of emotions was associated with worse mental health (p < 0.01). Type and clinical severity of FD were not associated with coping behavior. Patients with FD have different coping strategies compared to random Dutch reference populations with or without pain. In FD, using more passive coping strategies was associated with more impairment in several aspects of QoL. There was no relationship between coping behavior and clinical characteristics, pointing to biomedical variables not determining the way patients cope with their illness. Recognition of less effective coping strategies can be helpful in the understanding and adaptation of these coping strategies, improving personalized clinical care, with the ultimate goal to improve QoL in patients with FD.


Assuntos
Adaptação Psicológica , Displasia Fibrosa Óssea/psicologia , Qualidade de Vida/psicologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
7.
Calcif Tissue Int ; 102(1): 23-31, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29022055

RESUMO

Fibrous dysplasia (FD) is a rare bone disorder in which normal bone is replaced by fibrous tissue resulting in pain, deformities, pathological fractures or asymptomatic disease. Illness perceptions are patients' cognitions and emotions about their illness and its treatment, which may impact on Quality of Life (QoL). Here, we explore illness perceptions in patients with FD compared to other disorders, identify factors associated with illness perceptions and evaluate their relationship with QoL. Ninety-seven out of 138 eligible patients from the LUMC FD cohort completed the Illness Perception Questionnaire-Revised (IPQ-R) and the Short Form-36 (SF-36). Age, Gender, Skeletal Burden Score (SBS), FGF-23 levels, type of FD and SF-36 scores were analysed for an association with illness perceptions. We observed significant (p < 0.01) differences in patients' illness perceptions between FD subtypes in the domains: identity, timeline acute/chronic and consequences. Patients with craniofacial FD reported to perceive more consequences (p = 0.022). High SBS was associated with perceiving more negative consequences and attributing the cause of FD to psychological factors (p < 0.01), and high FGF-23 levels with attributing more symptoms to the disease and perceiving more consequences (p < 0.01). The IPQ-R domain identity, timeline acute/chronic, timeline cyclical, consequences, emotional representations and treatment control were significantly associated with impairments in QoL. Illness perceptions in patients with FD relate to QoL, differ from those in patients with other disorders, and are associated with disease severity. Identifying and addressing maladaptive illness perceptions may improve quality of life in patients with FD.


Assuntos
Displasia Fibrosa Óssea/psicologia , Dor/psicologia , Percepção/fisiologia , Qualidade de Vida , Autogestão/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fator de Crescimento de Fibroblastos 23 , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
8.
Isr J Psychiatry Relat Sci ; 48(2): 136-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22120450

RESUMO

Clinical Dilemma: You have diagnosed a 33-year-old male with bipolar disorder and initiated lithium treatment and psycho-social therapy. Two months later his lithium level is within the therapeutic range but his symptoms and function level correlate with moderate depressive episode. Is there a place for adjunctive antidepressant medication?


Assuntos
Antidepressivos/administração & dosagem , Antidepressivos/efeitos adversos , Transtorno Bipolar/tratamento farmacológico , Humanos
9.
Neuroscience ; 190: 37-42, 2011 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-21683126

RESUMO

Previously selected amyloid beta recognizing heavy chain antibody fragments (VHH) affinity binders derived from the Camelid heavy chain antibody repertoire were tested for their propensity to cross the blood-brain barrier (BBB) using an established in vitro BBB co-culture system. Of all tested VHH, ni3A showed highest transmigration efficiency which is, in part, facilitated by a three amino acid substitutions in its N-terminal domain. Additional studies indicated that the mechanism of transcellular passage of ni3A is by active transport. As VHH ni3A combines the ability to recognize amyloid beta and to cross the BBB, it has potential as a tool for non-invasive in vivo imaging and as efficient local drug targeting moiety in patients suffering from cerebral amyloidosis such as Alzheimer's disease (AD) and cerebral amyloid angiopathy (CAA).


Assuntos
Peptídeos beta-Amiloides/imunologia , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Cadeias Pesadas de Imunoglobulinas/metabolismo , Doença de Alzheimer/metabolismo , Transporte Biológico/fisiologia , Síndrome de Down/metabolismo , Humanos , Fragmentos de Imunoglobulinas/metabolismo
10.
J Clin Oncol ; 21(10): 1904-11, 2003 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-12743142

RESUMO

PURPOSE: This trial tested the hypothesis that combined androgen suppression (CAS) and whole-pelvic (WP) radiotherapy (RT) followed by a boost to the prostate improves progression-free survival (PFS) by 10% compared with CAS and prostate-only (PO) RT. This trial also tested the hypothesis that neoadjuvant and concurrent hormonal therapy (NCHT) improves PFS compared with adjuvant hormonal therapy (AHT) by 10%. MATERIALS AND METHODS: Eligibility included localized prostate cancer with an elevated prostate-specific antigen (PSA) < or = 100 ng/mL and an estimated risk of lymph node (LN) involvement of 15%. Between April 1, 1995, and June 1, 1999, 1,323 patients were accrued. Patients were randomly assigned to WP + NCHT, PO + NCHT, WP + AHT, or PO + AHT. Failure for PFS was defined as the first occurrence of local, regional, or distant disease; PSA failure; or death for any cause. RESULTS: With a median follow-up of 59.5 months, WP RT was associated with a 4-year PFS of 54% compared with 47% in patients treated with PO RT (P =.022). Patients treated with NCHT experienced a 4-year PFS of 52% versus 49% for AHT (P =.56). When comparing all four arms, there was a progression-free difference among WP RT + NCHT, PO RT + NCHT, WP RT + AHT, and PO RT + AHT (60% v 44% v 49% v 50%, respectively; P =.008). No survival advantage has yet been seen. CONCLUSION: WP RT + NCHT improves PFS compared with PO RT and NCHT or PO RT and AHT, and compared with WP RT + AHT in patients with a risk of LN involvement of 15%.


Assuntos
Antagonistas de Androgênios/administração & dosagem , Antineoplásicos Hormonais/administração & dosagem , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/radioterapia , Idoso , Idoso de 80 Anos ou mais , California , Quimioterapia Adjuvante , Terapia Combinada , Intervalo Livre de Doença , Esquema de Medicação , Humanos , Metástase Linfática , Masculino , Massachusetts , Michigan , Pessoa de Meia-Idade , Terapia Neoadjuvante , Cidade de Nova Iorque , Ohio , Pennsylvania , Modelos de Riscos Proporcionais , Estudos Prospectivos , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Radioterapia Conformacional , Texas , Resultado do Tratamento , Wisconsin
11.
Int J Radiat Oncol Biol Phys ; 51(5): 1299-304, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11728690

RESUMO

PURPOSE: Patients with recurrent squamous cell cancer of the head and neck (SCH&N) are generally treated with systemic chemotherapy. Improvement in survival has not occurred, despite an increased objective response rate. This study was undertaken to explore the feasibility and toxicity, and estimate the therapeutic impact of, reirradiation (RRT) with concurrent hydroxyurea and 5-fluorouracil. METHODS AND MATERIALS: The eligibility requirements included SCH&N presenting as a second primary or recurrence > or =6 months after definitive RT to > or =45 Gy, with > or =75% of the tumor volume within the previous field. The cumulative spinal cord dose was limited to 50 Gy, and measurable disease was required. Four weekly cycles were given, each separated by 1 week of rest. A cycle consisted of 5 days, Monday through Friday, of 1.5-Gy twice-daily repeated RT, with the fractions separated by > or =6 h, with 1.5 g of hydroxyurea given 2 h and 300 mg/m2 of a 5-fluorouracil IV bolus given 30 min before each second daily fraction. RESULTS: Eighty-six patients were entered; 81 patients were assessable. The median prior radiation dose was 61.2 Gy. The 4 planned cycles were delivered in 79% of patients. Grade 3 mucositis occurred in 14% of patients, and Grade 4 in 5%. Grade 3 acute pharyngeal toxicity was seen in 17%. Grade 3 neutropenia occurred in 9%, Grade 4 in 10%, and Grade 5 in 7%. Six patients died of treatment-related toxicity. Two died of hemorrhage from the tumor site without thrombocytopenia. With a median follow-up of 16.3 months for living patients, the estimated median overall survival was 8.2 months and the estimated 1-year survival rate 41.7%. Patients treated >3 years after the previous RT had a 1-year survival rate of 48% compared with 35% for patients treated within 3 years (p = 0.017). The 1-year survival rate for patients with a second primary was 54% compared with 38% for patients with recurrence (p = 0.083). CONCLUSION: Repeated RT with concurrent chemotherapy as given in this study is a feasible approach for selected, previously irradiated patients with SCH&N and may produce increased median and 1-year survival rates compared with systemic chemotherapy trials reported in the literature. A randomized study should be conducted to compare these two different approaches.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/radioterapia , Fluoruracila/uso terapêutico , Neoplasias de Cabeça e Pescoço/radioterapia , Hidroxiureia/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/mortalidade , Terapia Combinada , Feminino , Fluoruracila/efeitos adversos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Hidroxiureia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida
12.
J Biol Chem ; 276(51): 47834-9, 2001 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-11592960

RESUMO

The interaction of the coatomer coat complex with the Golgi membrane is initiated by the active, GTP-bound state of the small GTPase ADP-ribosylation factor 1 (ARF1), whereas GTP hydrolysis triggers coatomer dissociation. The hydrolysis of GTP on ARF1 depends on the action of members of a family of ARF1-directed GTPase-activating proteins (GAPs). Previous studies in well defined systems indicated that the activity of a mammalian Golgi membrane-localized ARF GAP (GAP1) might be subjected to regulation by membrane lipids as well as by the coatomer complex. Coatomer was found to strongly stimulate GAP-dependent GTP hydrolysis on a membrane-independent mutant of ARF1, whereas we reported that GTP hydrolysis on wild type, myristoylated ARF1 loaded with GTP in the presence of phospholipid vesicles was coatomer-independent. To investigate the regulation of ARF1 GAPs under more physiological conditions, we studied GTP hydrolysis on Golgi membrane-associated ARF1. The activities at the Golgi of recombinant GAP1 as well as coatomer-depleted fractions from rat brain cytosol resembled those observed in the presence of liposomes; however, unlike in liposomes, GAP activities on Golgi membranes were approximately doubled upon addition of coatomer. By contrast, endogenous GAP activity in Golgi membrane preparations was unaffected by coatomer. Cytosolic GAP activity was partially reduced following immunodepletion of GAP1, indicating that GAP1 plays a significant although not exclusive role in the regulation of GTP hydrolysis at the Golgi. Unlike the activities of the mammalian proteins, the Saccharomyces cerevisiae Glo3 ARF GAP displayed activity at the Golgi that was highly dependent on coatomer. We conclude that ARF GAPs in themselves can efficiently stimulate GTP hydrolysis on ARF1 at the Golgi, and that coatomer may play an auxiliary role in this reaction, which would lead to an increased cycling rate of ARF1 in COPI-coated regions of the Golgi membrane.


Assuntos
Fator 1 de Ribosilação do ADP/metabolismo , Complexo de Golgi/metabolismo , Guanosina Trifosfato/metabolismo , Animais , Cromatografia por Troca Iônica , Hidrólise , Membranas Intracelulares/metabolismo , Fosfatidilinositóis/metabolismo , Ratos , Proteínas de Saccharomyces cerevisiae/metabolismo
15.
Int J Radiat Oncol Biol Phys ; 51(2): 371-83, 2001 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11567811

RESUMO

PURPOSE: To compare acute toxicity, tumor response, and sphincter preservation in three schedules of concurrent chemoradiation in resectable transmural and/or node-positive extraperitoneal rectal cancer. PATIENTS AND METHODS: Between 1990 and 1999, 163 consecutive patients were treated according to the following combined modalities: FUMIR: between 1990 and 1995, 83 patients were treated with bolus i.v. mitomycin C (MMC), 10 mg/m(2) day 1, plus 24-h continuous infusion i.v. 5-fluorouracil (5-FU) 1,000 mg/m(2) days 1-4, and concurrent external beam radiotherapy (37.8 Gy). PLAFUR-4: between 1995 and 1998, 40 patients were treated with cisplatin (c-DDP) 60 mg/m(2) given as slow infusion (1-4 h) on days 1 and 29, plus 24-h continuous infusion i.v. 5-FU 1,000 mg/m(2), days 1-4 and 29-32 with concurrent external-beam radiotherapy (50.4 Gy). PLAFUR-5: between 1998 and 1999, 40 patients were treated with c-DDP 60 mg/m(2) given as slow infusion (during 1-4 h) on days 1 and 29, plus 24-h continuous infusion i.v. 5-FU 1,000 mg/m(2), days 1-5 and 29-33 with concurrent external-beam radiotherapy (50.4 Gy). RESULTS: Grade > or = 3 acute toxicity occurred in 14%, 5%, and 17% of patients treated in the FUMIR, PLAFUR-4, and PLAFUR-5 studies, respectively (p = 0.201). In the FUMIR, PLAFUR-4, and PLAFUR-5 studies, clinical response rate was 77%, 70%, and 83%, respectively. Tumor downstaging occurred in 57%, 68%, and 58% of patients, respectively. Pathologic complete response was recorded in 9% (FUMIR), 23% (PLAFUR-4), and 20% (PLAFUR-5) of patients. Sphincter-preserving surgery was feasible in 44% (FUMIR), 40% (PLAFUR-4), and 61% (PLAFUR-5) of patients having a distance between the anal-rectal ring and the lower pole of the tumor of 0-30 mm, and in 95%, 100%, and 100%, respectively, in those having a distance of 31-50 mm. Comparing FUMIR vs. PLAFUR, the clinical response rate was similar in the two series: a partial response was observed in 62/81 (77%) patients with FUMIR treatment, and in 61/80 (76%) patients with PLAFUR treatment. Tumor downstaging was observed in 46/81 (57%) patients and in 50/80 (68%) patients, respectively. The pathologic complete response rate was statistically higher in the PLAFUR series: 7/81 (9%) patients with FUMIR treatment and 17/80 (21%) patients with PLAFUR treatment (p = 0.04). Major downstaging (pT0+ pTmic+ pT1) in the FUMIR group was reported in 12/81 (15%) patients versus 31/80 (39%) patients in the PLAFUR group (p = 0.0006). The anal sphincter was preserved in 63/81 (78%) patients with FUMIR treatment and in 69/80 (86%) patients with PLAFUR treatment. The perioperative morbidity was statistically lower with PLAFUR: a perioperative morbidity was experienced by 20/81 (25%) patients with FUMIR treatment and by 9/80 (11%) patients with PLAFUR treatment (p = 0.042). CONCLUSION: In our experience, higher radiation dose (50.4 Gy vs. 37.8 Gy), a second course of concurrent 5-FU, and the use of c-DDP instead of MMC improved the pathologic response rate without increasing acute toxicity and perioperative morbidity. The use of 5-FU 5-day infusion (PLAFUR-5) resulted in higher toxicity with a similar response rate compared to 4-day infusion (PLAFUR-4).


Assuntos
Canal Anal/cirurgia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Diarreia/etiologia , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Leucopenia/etiologia , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Mitomicina/efeitos adversos , Estadiamento de Neoplasias , Seleção de Pacientes , Estudos Prospectivos , Dosagem Radioterapêutica , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia
16.
Skeletal Radiol ; 30(4): 192-8, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11392292

RESUMO

OBJECTIVE: To report on the imaging evolution of florid reactive periostitis (FRP) and bizarre parosteal osteochondromatous proliferation (BPOP) of the phalanges of the hands from prospective diagnosis to operation and on postsurgical outcome. DESIGN AND PATIENTS: Three patients (2 female, 1 male; age range 11-34 years) presented with a swollen digit of the hand. Following presumptive radiographic diagnosis of FRP, they were closely observed both clinically and radiographically until operation. All three patients had radiographs of the involved digit, and one patient had an MR imaging examination. The interval between presumptive diagnosis and operation ranged from 2 to 8 months. Following operation, the patients have been clinically followed for 9-13 months (mean 10 months). RESULTS: In each of the patients, maturing of periosteal reaction without bone destruction was observed within 1-2 weeks of the presumptive diagnosis of FRP. Periosteal reaction was initially minimal in relation to the extent of soft tissue swelling and subsequently became more florid. In one patient, the lesion ossified, became adherent to the phalanx, and had an "osteochondromatous" appearance. In another patient, periosteal reaction was seen on both sides of the phalanx with an intact phalanx. In the sole patient who had MR imaging, edema was seen in the phalanx distal to the symptomatic site and the metacarpal proximal to the symptomatic site. CONCLUSIONS: Close clinical and radiographic correlation permits an accurate pre-biopsy diagnosis of FRP. The first follow-up radiograph taken within 2 weeks usually provides re-assurance of the accuracy of the diagnosis. FRP may progress to BPOP. Arbitrary antibiotic treatment can be avoided, and a planned surgical approach can be adopted.


Assuntos
Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/cirurgia , Osteocondroma/diagnóstico por imagem , Osteocondroma/cirurgia , Periostite/diagnóstico por imagem , Periostite/cirurgia , Adulto , Criança , Feminino , Dedos , Humanos , Masculino , Radiografia , Resultado do Tratamento
18.
Am J Clin Oncol ; 24(6): 623-7, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11801768

RESUMO

Standard management of advanced carcinoma arising from the base of the tongue or infiltrating that region from contiguous areas (henceforth referred to as base of tongue complex [BTC] tumors) with radical surgery and postoperative radiation therapy results in extensive loss of function affecting deglutition, speech, and physical appearance. From January 1995, 16 patients with advanced stage BTC tumors were entered in this phase II study. Eleven patients (74%) had N2-3 neck disease. To optimize neck control, those with clinical N+ nodes at presentation had neck dissection. This was followed by hyperfractionated radiotherapy at 120 cGy twice daily to a median dose of 7,320 cGy to the primary and 6,240 cGy to areas with pathologically positive nodes. Concomitant chemotherapy was administered during weeks 1 and 4 of the radiation therapy using bolus cisplatin 75 to 100 mg/m2 on day 1 and continuous infusional 5-fluorouracil 750 to 1,000 mg/m2/d from days 1 to 4 of each chemotherapy cycle. Survival curves were plotted for various events, using actuarial life table methods. A functional assessment was made at least 1 year after completion of treatment using a previously validated Head/Neck Performance Status Scale. The median follow-up period was 23 months. There was a 100% complete response to the treatment at the primary site. The actuarial 4-year local (primary site) control was 100%, locoregional control (including nodes) was 69%, and disease-specific survival was 70% at 4 years. The predominant acute toxicity (63% incidence) was reversible grade III mucositis resulting in a median of 9 days' interruption in treatment. All of the patients were able to complete the prescribed treatment course, and there were no treatment-related deaths. Quality of Life assessment after treatment examined all facets of oropharyngeal function. Of note, none of the patients required long-term tube feedings. For the nine patients who responded to the functional assessment questionnaire, the results were excellent (score >75). The mean score for ability to eat in public was 75, mean of 76 for normalcy of diet, and 91 for understandability of speech. Concomitant hyperfractionated chemoradiation therapy produced excellent functional preservation with good long-term control in this patient group with historically poor prognosis. A 4-year actuarial local control rate of 69% was obtained, which is comparable to results of radical surgery and adjuvant radiation therapy. Further studies with modifications of fractionation and use of newer chemotherapy agents/radioprotectors will improve on these gains while reducing toxicity.


Assuntos
Carcinoma de Células Escamosas/terapia , Qualidade de Vida , Neoplasias da Língua/terapia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada , Deglutição , Intervalo Livre de Doença , Fracionamento da Dose de Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Otorrinolaringológicos , Faringe , Indução de Remissão , Fala
20.
J Biol Chem ; 275(31): 23615-9, 2000 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-10811810

RESUMO

The binding of the coat protein complex, coatomer, to the Golgi is mediated by the small GTPase ADP-ribosylation factor-1 (ARF1), whereas the dissociation of coatomer, requires GTP hydrolysis on ARF1, which depends on a GTPase-activating protein (GAP). Recent studies demonstrate that when GAP activity is assayed in a membrane-free environment by employing an amino-terminal truncation mutant of ARF1 (Delta17-ARF1) and a catalytic fragment of the ARF GTPase-activating protein GAP1, GTP hydrolysis is strongly stimulated by coatomer (Goldberg, J., (1999) Cell 96, 893-902). In this study, we investigated the role of coatomer in GTP hydrolysis on ARF1 both in solution and in a phospholipid environment. When GTP hydrolysis was assayed in solution using Delta17-ARF1, coatomer stimulated hydrolysis in the presence of the full-length GAP1 as well as with a Saccharomyces cerevisiae ARF GAP (Gcs1) but had no effect on hydrolysis in the presence of the phosphoinositide dependent GAP, ASAP1. Using wild-type myristoylated ARF1 loaded with GTP in the presence of phospholipid vesicles, GAP1 by itself stimulated GTP hydrolysis efficiently, and coatomer had no additional effect. Disruption of the phospholipid vesicles with detergent resulted in reduced GAP1 activity that was stimulated by coatomer, a pattern that resembled Delta17-ARF1 activity. Our findings suggest that in the biological membrane, the proximity between ARF1 and its GAP, which results from mutual binding to membrane phospholipids, may be sufficient for stimulation of ARF1 GTPase activity.


Assuntos
Fator 1 de Ribosilação do ADP/metabolismo , Proteína Coatomer/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Guanosina Trifosfato/metabolismo , Fosfolipídeos/metabolismo , Fator 1 de Ribosilação do ADP/genética , Arginina/genética , Proteínas de Transporte/metabolismo , Proteínas Ativadoras de GTPase/genética , Hidrólise , Mutação , Ácido Mirístico/metabolismo , Processamento de Proteína Pós-Traducional , Deleção de Sequência
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