RESUMEN
CONTEXT: Patients with Cushing's syndrome (CS) of any etiology experience a number of physical and psychological symptoms which impact negatively on health-related quality of life (HRQoL). SUBJECTS AND METHODS: HRQoL was measured using CushingQoL questionnaire. RESULTS: The first part of our study was a cross-sectional analysis of 141 patients with CS over a 10-year period. CushingQoL score was lower in pituitary CS compared to adrenal CS. Remission and older age were associated with better outcome on item 7 (physical appearance anxiety). In a multivariate regression analysis after adjustment for etiology, remission status, age, UFC, duration of hypercortisolism and presence of hypercortisolism-associated comorbidities the female gender was the only negative predictor associated with poorer outcome on each of the three scores. The presence of hypercortisolism-associated comorbidities independently predicted poorer outcome on the psychological and the global subscales.The second part of our research was a prospective study of 27 patients with adrenal adenoma. Achievement of remission independently predicted improvement of the total score of any patient. CONCLUSION: Studying in details and understanding the mechanisms of the impaired HRQoL in patients with CS is the only way to become aware of the problem and create methods that could help these patients.
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OBJECTIVE: We described biochemical outcome in regards to different treatment modalities in patients with acromegaly in Bulgaria. PATIENTS AND METHODS: It was a retrospective analysis using data from the Bulgarian Acromegaly Database. Patients with eligible data on at least one treatment modality were included in the study. Disease control was assessed by both GH and IGF-1 values or by GH/IGF-1 alone in cases with one marker. Last follow-up was median 7.0 (range 0.5-51) years after diagnosis. RESULTS: We identified 534 patients with interpretable data, 65.4% of whom were females. Overall surgical cure rate was 28.8%. Adjuvant bromocriptine and cabergoline treatment was analyzed in 133 and 70 patients with disease control achieved in 18.8% and 31.4% respectively. Patients without prior radiotherapy had 16.3% and 18.2% control rates respectively. Predictors of response to dopamine agonist (DA) therapy were disease activity, radiotherapy and medication dose. Adjuvant somatostatin analog (SSA) treatment led to biochemical control in 38.6% of 70 patients. Combination of SSA and cabergoline led to remission in 25% of 20 patients. Growth hormone receptor antagonist (GHRA) alone or in combination resulted in remission in 61.5% of 13 patients. Approximately one third of the patients were cured median 10 years after irradiation. Overall disease control was observed in 51.4% of our patients increasing to 70.3% in the last 5 years of the study period. CONCLUSION: DAs are efficient in less than 20% of non-irradiated patients. They are a good cost-effective alternative for carefully selected patients.
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Acromegalia/terapia , Bromocriptina/administración & dosificación , Bases de Datos Factuales , Agonistas de Dopamina/administración & dosificación , Adolescente , Adulto , Anciano , Bulgaria , Cabergolina , Niño , Ergolinas/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Radioterapia/métodos , Inducción de Remisión , Estudios Retrospectivos , Somatostatina/administración & dosificaciónRESUMEN
PURPOSE: To look at the frequency of second primary malignancies (SECMAL) in patients with multiple myeloma (MM). METHODS: The medical files of 332 patients with MM (whole group), diagnosed and treated at the University Multiprofile Hospital for Active Treatment "Sv. Georgi" and the Comprehensive Oncology Hospital (Plovdiv) for a 20-year period (1990-2010) were retrospectively analyzed. MM patients with SECMAL constituted the study group. A control group comprised patients with solid tumors associated with SECMAL. This group derived from a sample of 21768 patients with solid tumors. RESULTS: In the study group, SECMAL was diagnosed in 4.52% (N=15) of the patients, while in the control group this figure was 5.09% (N=1108) (p>0.05). The diagnosis of MM preceded the occurrence of SECMAL in 35.71% of the study group patients, the median interval being 6.6 years (range 5-14). More frequently the diagnosis of the solid tumor preceded the occurrence of MM (66.67%). Breast cancer and gastric cancer were encountered with the highest frequency (26.67% each). The median survival (77.2 months, range 44-129) was significantly longer in the group with MM and SECMAL compared to the whole group with MM (median 38.6 months, range 10-58; p<0.05). CONCLUSION: The rate of MM with other malignant diseases is comparable with the frequency of SECMAL in other lymphoproliferative disorders and solid tumors. The occurrence of SECMAL during the clinical course of MM is not a frequent event and is expected in the rare cases with longer survival.
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Mieloma Múltiple/epidemiología , Neoplasias Primarias Secundarias/epidemiología , Adulto , Anciano , Bulgaria/epidemiología , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Mieloma Múltiple/mortalidad , Neoplasias Primarias Secundarias/mortalidad , Pronóstico , Estudios Retrospectivos , Factores de TiempoRESUMEN
Eighteen histone deacetylases (HDACs) are present in humans, categorized into two groups: zinc-dependent enzymes (HDAC1-11) and NAD(+)-dependent enzymes (sirtuins 1-7). Among zinc-dependent HDACs, HDAC6 is unique. It has a cytoplasmic localization, two catalytic sites, a ubiquitin-binding site, and it selectively deacetylases alpha-tubulin and Hsp90. Here, we report the discovery that the redox regulatory proteins, peroxiredoxin (Prx) I and Prx II are specific targets of HDAC6. Prx are antioxidants enzymes whose main function is H(2)O(2) reduction. Prx are elevated in many cancers and neurodegenerative diseases. The acetylated form of Prx accumulates in the absence of an active HDAC6. Acetylation of Prx increases its reducing activity, its resistance to superoxidation, and its resistance to transition to high-molecular-mass complexes. Thus, HDAC6 and Prx are targets for modulating intracellular redox status in therapeutic strategies for disorders as disparate as cancers and neurodegenerative diseases.
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Histona Desacetilasas/metabolismo , Peroxirredoxinas/metabolismo , Acetilación , Línea Celular Tumoral , Histona Desacetilasa 6 , Histona Desacetilasas/análisis , Humanos , Oxidación-Reducción , Estrés Oxidativo , Peróxidos/metabolismoRESUMEN
A case of solitary eosinophilic granuloma (EG) of the brain in a 53-year-old woman is presented. The tumor developed in the anterior cranial fossa causing destruction of the skull basis and the retrobulbar space, accompanied by vision impairment. The tumor was partially excised and the patient was irradiated postoperatively with 40 Gy 6 MV x-rays, followed by 10 cycles of chemotherapy. Follow-up computed tomography (CT) showed no response at 30 Gy and no progression during chemotherapy. Attention is drawn to cases of EG indolent in growth but resistant to radiation and chemotherapy.
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Neoplasias Encefálicas/radioterapia , Granuloma Eosinófilo/radioterapia , Trastornos de la Visión/etiología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Encefálicas/complicaciones , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/cirugía , Quimioterapia Adyuvante , Progresión de la Enfermedad , Granuloma Eosinófilo/complicaciones , Granuloma Eosinófilo/tratamiento farmacológico , Granuloma Eosinófilo/patología , Granuloma Eosinófilo/cirugía , Femenino , Humanos , Persona de Mediana Edad , Radioterapia Adyuvante , Base del Cráneo/patología , Tomografía Computarizada por Rayos X , Insuficiencia del Tratamiento , Trastornos de la Visión/radioterapiaRESUMEN
Therapy-related acute promyelocytic leukemia (t-APL) is a rare but known complication of chemotherapy and/or radiation therapy. Approximately 200 cases of t-APL have been reported in the literature up until now. The development of t-APL after radioiodine therapy is very rare, keeping in mind the very low doses of radiation exposure of the patient. We present a case of a 47-year-old woman with t-APL t15;17(q22;q21) developed after radioiodine treatment for thyroid carcinoma. The patient was treated with chemotherapy and achieved complete response lasting for 3(+) years. The patient's excellent response to treatment supports the data of the relevant literature that t-APL is associated with a better therapeutic result than the other subtypes of secondary acute myeloid leukemia (AML).
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Radioisótopos de Yodo/efectos adversos , Leucemia Promielocítica Aguda/etiología , Neoplasias Inducidas por Radiación/etiología , Neoplasias de la Tiroides/radioterapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Femenino , Humanos , Leucemia Promielocítica Aguda/tratamiento farmacológico , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/patología , Persona de Mediana Edad , Neoplasias Inducidas por Radiación/tratamiento farmacológico , Neoplasias Inducidas por Radiación/genética , Neoplasias Inducidas por Radiación/patología , Pronóstico , Neoplasias de la Tiroides/cirugía , Resultado del TratamientoRESUMEN
BACKGROUND: The aim of the study was to evaluate diurnal blood pressure (BP) profiles in patients with primary aldosteronism and to compare them to those in subjects with essential hypertension. The effects of specific therapy on the circadian BP profiles have been studied. MATERIALS AND METHODS: Sixty-four patients with primary aldosteronism were included in the study. Thirty of them revealed an aldosterone-producing adenoma (APA) and 34 had idiopathic hyperaldosteronism (IHA) due to bilateral adrenal hyperplasia. RESULTS: We did not find any significant differences in ambulatory BP monitoring (ABPM) between patients with APA and IHA. However, the circadian BP variation in the patients with primary hyperaldosteronism due to APA was preserved, while the patients with IHA showed lower nocturnal decline in comparison with patients with essential hypertension. There was a significant decline in office and ambulatory BP levels after treatment in the patients with both APA and IHA. The awake-sleep BP difference in patients with APA remained unchanged after surgical treatment, while in patients with IHA the night-time systolic and diastolic BP decline was significantly higher after spironolactone treatment. CONCLUSIONS: Primary hyperaldosteronism due to APA was associated with normal circadian BP variability and the surgical treatment led to highly significant decline in all BP parameters but had no influence on the extent of nocturnal BP variation. Spironolactone therapy restored normal nocturnal BP decline in patients with IHA. Reduction of night-time BP decline in patients with IHA is more likely to be related to the duration of the disease rather than to the aldosterone levels.
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Presión Sanguínea , Ritmo Circadiano/fisiología , Hiperaldosteronismo/fisiopatología , Adenoma/fisiopatología , Enfermedades de las Glándulas Suprarrenales/fisiopatología , Adulto , Monitoreo Ambulatorio de la Presión Arterial , Femenino , Humanos , Hiperaldosteronismo/terapia , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Sueño , Espironolactona/uso terapéutico , VigiliaRESUMEN
PURPOSE: To analyse the therapeutic effect of palliative radiation therapy (RT) in multiple myeloma (MM) patients with bone lesions and soft tissue formations, to compare the therapeutic efficacy of two different RT regimens, the effect of RT on basic disease parameters, and its impact on survival in MM patients. PATIENTS AND METHODS: 162 patients with MM were diagnosed and followed for a 10-year period (1994-2004). Eighty-seven (53.7%) of them with myeloma bone disease (MBD) underwent palliative RT with two different regimens. The effect of RT on MBD and its complications was assessed. Patients with RT were compared in 10 parameters before and after RT. Survival was compared between the irradiated and non irradiated groups and also between patients treated with two different RT regimens, using Kaplan-Meier method and log-rank test. RESULTS: RT was applied in 92.1% of the patients with vertebral fractures, in 90.9% of the patients with non-vertebral fractures, and in 94.1% of the patients with extramedullary tumor formations. In 89.6% of the patients complete or partial pain palliation was achieved and in 58.6% resolution of neurologic symptoms occurred. The levels of hemoglobin (Hb), white blood cell (WBC) and platelet counts (PLT), bone marrow infiltration, serum calcium (Ca), creatinine, albumin, CRP, LDH, beta2-microglobulin did not change significantly before and after RT. Median survival of patients on RT was 32 months (range 30-34) vs. 33 months (range 28-36) for patients without RT (p>0.05). Median survival was 32 months (range 27-37) for patients on 2x8 Gy. vs. 34 months (range 25-39) for those on 5x4 Gy (p>0.05). CONCLUSION: RT is a very effective method in bone pain palliation in vertebral and non-vertebral fractures and reduction of extramedullary formations, but does not influence the survival of patients with MM.
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Neoplasias Óseas/radioterapia , Mieloma Múltiple/radioterapia , Cuidados Paliativos , Neoplasias de los Tejidos Blandos/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Óseas/mortalidad , Neoplasias Óseas/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/mortalidad , Mieloma Múltiple/patología , Estadificación de Neoplasias , Dolor/radioterapia , Neoplasias de los Tejidos Blandos/mortalidad , Neoplasias de los Tejidos Blandos/patología , Fracturas de la Columna Vertebral/radioterapia , Tasa de SupervivenciaRESUMEN
The aim of the study was to evaluate the circadian blood pressure (BP) profiles in patients with two forms of Cushing's syndrome, and to compare them to those in patients with essential hypertension. The study included 100 patients with Cushing's syndrome (80 with pituitary adenomas and 20 with adrenal adenomas) and 40 with essential hypertension. Twenty-four-h ambulatory BP monitoring was performed before and after therapy. All 3 groups had similar office-, 24-h-, awake-, and sleep BP mean values. The awake-sleep differences between the patients with two forms of Cushing's syndrome were similar. The night-time BP decline in the patients with Cushing's disease, as well as in those with adrenal adenomas, was significantly lower than that in the patients with essential hypertension. In the patients with both forms of Cushing's syndrome, there was a highly significant decline in the office and ambulatory BP levels after the treatment, and the awake-sleep systolic BP difference became significantly higher. The night-time diastolic BP decline was significantly higher after treatment in patients with adrenal adenomas and not-significantly higher in patients with Cushing's disease. In the patients with Cushing's disease, the duration of hypertension was greater, and lower percentage of normalized BP after treatment was observed in comparison with the patients with adrenal adenomas. The significant negative correlation between duration of the disease and extent of the night-time BP decline suggests that the 'non-dipping' profile is related not only to hypercortisolism itself but also to the severity of hypertension and duration of the disease.
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Presión Sanguínea/fisiología , Ritmo Circadiano , Síndrome de Cushing/etiología , Síndrome de Cushing/terapia , Hipertensión/fisiopatología , Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT)/complicaciones , Adenoma/complicaciones , Neoplasias de las Glándulas Suprarrenales/complicaciones , Adulto , Femenino , Humanos , Hidrocortisona/sangre , Masculino , Persona de Mediana Edad , Hipersecreción de la Hormona Adrenocorticotrópica Pituitaria (HACT)/terapia , Índice de Severidad de la EnfermedadRESUMEN
UNLABELLED: The application of serum osteocalcine as a marker of osseous synthesis in patients with renal osteodystrophy is still disputable because of its predominantly renal excretion. The aim of the present study was to investigate the level of serum osteocalcine in pre-dialysis patients with chronic renal failure (CRF). MATERIAL AND METHODS: 47 patients aged 22-60 years (26 males and 22 females) with chronic renal failure were studied. 23 of them were stage I CRF patients (creatinine up to 353.6 mumol/l) and 24 were stage II and III CRF patients (creatinine up to 800 mumol/l). 35 healthy subjects (15 males and 20 females) were used as controls. Serum osteocalcine was measured by a radioimmunologic assay (ELSA-OSTEO-CIS, France). Serum creatinine, calcium, phosphorus and alkaline phosphatase were detected on a biochemical analyzer "Optima" (Kone Instruments, Finland) using the standard techniques recommended by IFCC. RESULTS: Serum osteocalcine was significantly elevated in patients with stage I CRF (45.61 +/- 7.75 ng/ml), compared to the control group (14.61 +/- 1.02, p < 0.001; u = 3.96). A significant increase was also found in patients with stage II and III CRF (120.48 +/- 15.96 ng/ml, p < 0.001; u = 4.22). No significant difference in osteocalcine level was found between male and female patients (83.77 +/- 15.09 vs. 94.52 +/- 16.88). 32 (68%) patients of the entire sample had osteocalcine above the reference values. These included 11 out of 23 patients with stage I CRF (47%) and 21 out of 24 patients with stage II and III CRF (87%). A moderately positive correlation was established between osteocalcine level and the duration of CRF (0.57), as well as between serum creatinine (0.39) and phosphorus (0.34). A moderately negative correlation was discovered between creatinine clearance (-0.42) and total serum calcium (-0.37). CONCLUSIONS: Serum osteocalcine could be used as a marker for bone synthesis in pre-dialysis patients with CRF. Our results indicate that more than 50% of the patients show evidence for renal osteodystrophy.
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Fallo Renal Crónico/sangre , Osteocalcina/sangre , Adulto , Calcio/sangre , Creatinina/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fósforo/sangre , Valores de ReferenciaRESUMEN
UNLABELLED: Therapeutical approach in brain metastases still remains the major problem in many cancer patients, especially in those with primary lung lesion. The aim of the present study was to test the tolerance to a whole brain telegammatherapy with a daily dose of 2 Gy in patients with lung cancer, to evaluate the improvement of sensory and motor deficits, and to define the more appropriate total dose (20 or 30 Gy) with regard to the patient survival. MATERIAL AND METHODS: Thirty nine patients with lung cancer and verified brain metastases underwent a whole brain telegammatherapy to a total dose of 20-30 Gy. Solitary metastases were found in 45 percent of the patients but all were defined as inoperable cases. The other patients had two or more brain lesions. RESULTS: All patients tolerated well the fraction and the total dose. The mean survival of the patients was 6.6 months with confidence interval 5.8-7.4 months. The survival difference between treatments with 20 and 30 Gy total dose did not reach statistical significance. Significant improvement was found in the Karnofsky index, intracranial pressure, headache, and neurologic symptoms after radiotherapy. CONCLUSION: Radiation therapy in patients with brain metastases from lung cancer is well tolerated and improves the quality of life.
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Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundario , Neoplasias Pulmonares/patología , Neoplasias Encefálicas/fisiopatología , Relación Dosis-Respuesta en la Radiación , Humanos , Persona de Mediana Edad , Calidad de Vida , Análisis de Supervivencia , Resultado del TratamientoRESUMEN
UNLABELLED: The aim of the present investigation was to examine the influence of age, sex and body weight on osseous changes in pre-dialysis patients with chronic renal failure (CRF). 87 patients (44 males and 43 females) aged 18-60 years with CRF were studied. The levels of serum creatinine, total and ionized calcium, phosphorus, alkaline phosphatase, intact parathormone and serum osteocalcine were followed up. Body weight is presented as BMI. 47 of the patients were subjected to double X-ray absorptiometry of lumbar vertebra (Lunar) and 40 patients were examined by computed tomography osteometry. RESULTS: No reliable differences in the levels of biochemical parameters in male and female patients with the same degree of CRF were established. A tendency towards an increase in the level of intact parathormone and serum osteocalcine in women with both initial and advanced CRF was recorded. The BMI in patients with advanced CRF was lower as compared to those with initial CRF. Different stages of osseous changes were observed in 29 males (74.35%) and in 25 females (60.97%). A tendency for a higher frequency and severity of osseous changes in men aged up to 40 years was observed. After this age males and females were equally affected. A high positive correlation (r = 0.50) between BMI and the percentage of the normal Bone Mineral Density/Bone Mineral Content in females with CRF stage II and III was noticed. CONCLUSIONS: No significant difference in the frequency and severity of osseous changes in male and female uremic patients was observed. Bone changes were more frequent and pronounced in males up to 40 years of age, while this tendency reversed after the menopause. The higher body weight was beneficial for the osseous changes only in females with advanced CRF, while in all other patients no correlation with densitometric parameters was noticed.
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Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/etiología , Fallo Renal Crónico/complicaciones , Adolescente , Adulto , Factores de Edad , Índice de Masa Corporal , Densidad Ósea , Femenino , Humanos , Fallo Renal Crónico/metabolismo , Fallo Renal Crónico/patología , Masculino , Persona de Mediana Edad , Factores SexualesRESUMEN
DNA-dependent protein kinase (DNA-PK) is the only eukaryotic protein kinase known to be specifically activated by double-stranded DNA (dsDNA) termini, accounting for its importance in repair of dsDNA breaks and its role in physiologic processes involving dsDNA breaks, such as V(D)J recombination. In this study we conducted kinase and binding analyses using DNA-PK on DNA termini of various lengths in the presence and absence of Ku. We confirmed our previous observations that DNA-PK can bind DNA termini in the absence of Ku, and we determined rate constants for binding. However, in the presence of Ku, DNA-PK can assume either a productive or a nonproductive configuration, depending on the length of the DNA terminus. For dsDNA greater than 26 bp, the productive mode is achieved and Ku increases the affinity of the DNA-PK for the Ku:DNA complex. The change in affinity is achieved by increases in both the kinetic association rate and reduction in the kinetic dissociation rate. For dsDNA smaller than 26 bp, the nonproductive mode, in which DNA-PK is bound to Ku:DNA but is inactive as a kinase, is assumed. Both the productive and nonproductive configurations are likely to be of physiologic importance, depending on the distance of the dsDNA break site to other protein complexes, such as nucleosomes.
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Antígenos Nucleares , ADN Helicasas , Proteínas de Unión al ADN/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , ADN/metabolismo , Proteína Quinasa Activada por ADN , Activación Enzimática , Células HeLa , Humanos , Autoantígeno Ku , Espectrometría de Masas , Conformación de Ácido Nucleico , Relación Estructura-ActividadRESUMEN
DNA-dependent protein kinase (DNA-PK or the scid factor) and Ku are critical for DNA end-joining in V(D)J recombination and in general non-homologous double-strand break repair. One model for the function of DNA-PK is that it forms a complex with Ku70/86, and this complex then binds to DNA ends, with Ku serving as the DNA-binding subunit. We find that DNA-PK can itself bind to linear DNA fragments ranging in size from 18 to 841 bp double-stranded (ds) DNA, as indicated by: (i) mobility shifts; (ii) crosslinking between the DNA and DNA-PK; and (iii) atomic-force microscopy. Binding of the 18 bp ds DNA to DNA-PK activates it for phosphorylation of protein targets, and this level of activation is not increased by addition of purified Ku70/86. Ku can stimulate DNA-PK activity beyond this level only when the DNA fragments are long enough for the independent binding to the DNA of both DNA-PK and Ku. Atomic-force microscopy indicates that under such conditions, the DNA-PK binds at the DNA termini, and Ku70/86 assumes a position along the ds DNA that is adjacent to the DNA-PK.
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Antígenos Nucleares , ADN Helicasas , Proteínas de Unión al ADN/metabolismo , ADN/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Western Blotting , Caseínas/metabolismo , ADN/química , ADN/ultraestructura , Reparación del ADN , ADN Superhelicoidal/metabolismo , Proteína Quinasa Activada por ADN , Proteínas de Unión al ADN/aislamiento & purificación , Proteínas de Unión al ADN/ultraestructura , Electroforesis en Gel de Poliacrilamida , Activación Enzimática/fisiología , Enzimas Inmovilizadas , Células HeLa , Humanos , Autoantígeno Ku , Microscopía de Fuerza Atómica , Proteínas Nucleares/aislamiento & purificación , Proteínas Nucleares/ultraestructura , Conformación de Ácido Nucleico , Fosforilación , Proteínas Serina-Treonina Quinasas/aislamiento & purificación , Proteínas Serina-Treonina Quinasas/ultraestructura , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Rayos UltravioletaRESUMEN
A convergence of information from biochemistry, yeast and mammalian genetics, immunology, and radiation biology has permitted identification of some of the protein participants - Ku, DNA-PK, XRCC4 - and the reaction intermediates in DNA end joining, suggesting how broken chromosomal ends may be recognized and repaired in eukaryotic cells. Some components may be defective in inherited disorders.
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Antígenos Nucleares , ADN Helicasas , Reparación del ADN/fisiología , Proteínas de Unión al ADN/fisiología , Proteínas Nucleares/fisiología , Proteínas Serina-Treonina Quinasas/fisiología , Proteínas de Saccharomyces cerevisiae , Animales , Proteína Quinasa Activada por ADN , Autoantígeno Ku , Levaduras/genéticaRESUMEN
The Ku protein, a DNA-binding complex that is composed of two subunits of 70 kDa and of 86 kDa, has been suggested to play a role in gene transcription. The dependence of the in vitro DNA-binding activity of affinity-purified Ku protein on reduced cysteine residues has been studied using sulphydryl-modifying agents. Inhibition of the DNA-binding activity was caused by alkylation with N-ethylmaleimide and by crosslinking with azadicarboxylic acid bis(dimethylamide). Treatment of the protein with a large excess of N-ethylmaleimide after it had bound to DNA did not completely dissociate the complex from the DNA, suggesting that some cysteines may be in direct contact with DNA. Pre-incubation of the protein at 37 degrees C or above caused rapid inactivation of DNA binding. The elevated temperature azadicarboxylic acid bis(dimethylamide) treatments resulted in the formation of a crosslinked product, which was detected by Western blotting. The effects of azadicarboxylic acid bis(dimethylmaleimide) and heat were completely reversible by treatment with a reducing agent, such as dithiothreitol. These results demonstrate that in vitro DNA-binding activity of the Ku protein requires reduced sulphydryl groups. Interestingly, the DNA-binding activity of Ku protein was protected from heat inactivation by the presence of a HeLa cell nuclear extract, suggesting that a nuclear factor or factors may be responsible for the maintenance of the reduced cysteines of the Ku protein in vivo. Thus, the biochemical function of the Ku protein may be regulated through oxidation-reduction of its cysteine residues.
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Antígenos Nucleares , Cisteína/metabolismo , ADN Helicasas , Proteínas de Unión al ADN/metabolismo , ADN/metabolismo , Proteínas Nucleares/metabolismo , Autoantígenos , Cisteína/química , Células HeLa , Calor , Humanos , Concentración de Iones de Hidrógeno , Autoantígeno Ku , Oxidación-ReducciónRESUMEN
To find the association between survival and various prognostic factors such as age, extent of surgical intervention, duration of complaints, site of tumour, histologic grade of the tumours and the Karnofsky performance status, we studied retrospectively 179 patients with histologically proven cerebral gliomas treated postoperatively in the Radioisotopic Center from 1976 to 1989. The patient's histologic tumour grade, the Karnofsky performance status and age proved to be particularly very indicative for longer survival time. The obligatory treatment with postoperative radiation therapy has been discussed in our previous works in connection with irradiated volume and a total radiation tumor dose. The state of the patients prior to postoperative telegamma therapy (Karnofsky Performance Status) is of major importance both for the therapeutic effect of irradiation and for the quality and duration of patient's further life. Patients with low-grade tumours (I and II), the Karnofsky performance status of 70% to 90% and age under 40 years live longer.
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Astrocitoma/radioterapia , Neoplasias Supratentoriales/radioterapia , Adulto , Astrocitoma/cirugía , Terapia Combinada , Humanos , Pronóstico , Estudios Retrospectivos , Neoplasias Supratentoriales/cirugíaRESUMEN
Sera from certain patients with SLE, scleroderma and other autoimmune diseases react with the two subunits of the Ku protein: 86 and 70 kDa. Previous experiments indicated that a region of 40 amino acids near the C-terminus of the 86 kDa subunit between amino acids 667 and 708 was critical for binding of monoclonal and some autoimmune antibodies. In the present study, a series of additional 5' deletions and site-specific mutations in the critical region were produced and the immunoreactivities of the recombinant proteins were examined. ELISA and immunoblot analyses showed that three non-competing monoclonal antibodies specific for the 86 kDa subunit require stretches of amino acids significantly longer than 40 amino acids for reactivity, suggesting that the antigen is recognized in a folded state with perhaps more than one contact point. The reactivities of 12 of 24 anti-Ku positive autoimmune sera screened depended on the same amino acid sequences required for binding of the monoclonal antibodies, site-specific mutations reduced the reactivities of monoclonal and autoantibodies in a similar way. Preincubation of native Ku protein with the monoclonal antibodies shifted the electrophoretic mobility of Ku protein-DNA complex, suggesting that these monoclonal antibodies bind to epitopes on the surface of the native Ku protein. Taken together, the results from the deletion and site-directed mutagenesis demonstrate that both monoclonal and autoantibodies recognize non-linear epitopes of the 86 kDa polypeptide. These findings indicate that in a large portion of patients the anti-Ku autoimmune response is similar to the normal immune response to the Ku antigen in mice.
Asunto(s)
Antígenos Nucleares , Autoantígenos/inmunología , ADN Helicasas , Proteínas de Unión al ADN/inmunología , Epítopos/inmunología , Proteínas Nucleares/inmunología , Anticuerpos Monoclonales/inmunología , Autoanticuerpos/inmunología , Enfermedades Autoinmunes/inmunología , Western Blotting , Ensayo de Inmunoadsorción Enzimática , Humanos , Autoantígeno Ku , Mutagénesis Sitio-Dirigida , Proteínas Recombinantes de Fusión/inmunologíaRESUMEN
PURPOSE: Patients with primary pulmonary hypertension (PPH) frequently have Raynaud's phenomenon, serum antinuclear antibodies (ANAs), and/or pulmonary vascular lesions similar to those seen in certain connective tissue diseases, especially scleroderma. A number of relatively disease-specific autoantibodies have been described in connective tissue diseases but have not been studied in patients with PPH. Therefore, sera from PPH patients were studied for a variety of autoantibodies, seeking a possible link between this pulmonary disorder and connective tissue diseases. PATIENTS AND METHODS: Sera from 31 patients with PPH and 24 with secondary pulmonary hypertension (SPH) were studied for the following autoantibodies: anti-centromere (indirect immunofluorescence of Hep-2 cells), anti-CENP-B by immunoblotting and enzyme immunoassay (EIA) using cloned CENP-B fusion protein, anti-topoisomerase I (Scl-70), anti-Ku using immunoblotting of affinity purified antigens, anti-cardiolipin using EIA, and anti-Ro (SS-A), La (SS-B), Sm, nRNP, Jo-1, PM-Scl, and Mi-2 by counter-current immunoelectrophoresis. RESULTS: Anti-Ku antibodies were found in 23% of patients with PPH, 4% with SPH, and none of 24 normal controls (PPH versus SPH, p = 0.06: PPH versus controls, p = 0.01). Antibodies to CENP-B were found in one patient each with PPH and SPH, anti-topoisomerase I in one with SPH, and anti-Ro (SS-A) and La (SS-B) in one with PPH. Overall, 12 patients (39%) with PPH had Raynaud's phenomenon or positive ANA results, with 9 (29%) having more specific autoantibodies associated with connective tissue diseases. CONCLUSIONS: These results further suggest a link between at least a subgroup of patients with PPH and autoimmune connective tissue diseases, with anti-Ku antibodies being a possible new serologic marker.
Asunto(s)
Antígenos Nucleares , Autoanticuerpos/sangre , Autoantígenos/inmunología , ADN Helicasas , Proteínas de Unión al ADN/inmunología , Hipertensión Pulmonar/inmunología , Proteínas Nucleares/inmunología , Adulto , Biomarcadores/sangre , Enfermedades del Tejido Conjuntivo/inmunología , Femenino , Humanos , Immunoblotting , Autoantígeno Ku , Masculino , Persona de Mediana EdadRESUMEN
Autoantibodies against Ku antigen were found in subsets of sera from patients with rheumatic diseases. The Ku autoantigen was characterized as a DNA-binding protein complex composed of two subunits, 70 and 86 kDa. In this study, we report the amino acid sequences of the 70-kDa subunit that are important for interactions with a monoclonal and autoimmune antibodies. Full-length cDNA and numerous 5' and 3' deletion mutants were expressed in bacteria and the immunoreactivity of the fusion proteins was analyzed by Western blotting. The reactivity of the monoclonal antibody depended on the region between Ile321 and Phe350. Ten autoimmune sera were tested for reactivity with deletion mutants in immunoblots. The reactivity of six sera strongly depended on the C-terminal amino acids and four sera did not show such dependence; however, these C-terminal sequences did not react with the sera when expressed alone. These results strongly suggest the conformational nature of the Ku autoepitopes. Interestingly, the DNA-binding activity of this Ku protein subunit analyzed by Southwestern blot depended on the same C-terminal amino acids that were involved in interactions with autoantibodies, indicating that anti-Ku autoantibodies are directed to conformationally intact Ku antigen. Reactivities of the autoimmune sera with Met1-Arg115, Met116-Val149, and Val149-Arg586 were also observed. These results demonstrate that different amino acid regions can be involved in interactions with autoimmune antibodies.