RESUMEN
Multiple myeloma (MM) is a malignancy with excessive production of monoclonal proteins. At disease presentation 30% of MM patients have significant renal impairment which may progress to renal failure requiring dialysis. Besides chemotherapy extracorporeal elimination procedures such as plasma exchange have been applied as adjuvant strategies to eliminate free light chains from circulating blood, however the efficacy was poor with older techniques. We report about a highly efficient method to eliminate serum free light chain (sFLC) using a newly designed protein leaking membrane in patients suffering from sFLC induced acute renal failure. The protein leaking membrane (HCO 1100) is characterized by increased pore size facilitating elimination of middle molecules such as sFLC kappa (22.5 kD). The HCO 1100 membrane was applied in a hemodialysis and hemodiafiltration mode and compared to standard procedures (high flux hemodialysis, hemodiafiltration and plasma exchange). Hemodiafiltration with the protein leaking membrane HCO 1100 was superior to all other extracorporeal replacement strategies in eliminating sFLC-kappa from circulating blood. A median blood reduction rate of 40.8% (range 13.9%-66.4%) was achieved during hemodiafiltration. The corresponding peak clearance rate was 25 ml/min. Importantly, the poorest elimination rate was achieved by plasma exchange followed by standard high flux hemodialysis. Extracorporeal elimination strategies with the protein leaking membrane HCO 1100 may be a promising adjuvant treatment strategy for patients with sFLC nephropathy requiring dialysis. Hemodiafiltration and to lesser extend also hemodialysis with the HCO 1100 hemofilter are able to eliminate substantial amounts of sFLC kappa in MM patients.
Asunto(s)
Lesión Renal Aguda/terapia , Hemodiafiltración/métodos , Cadenas kappa de Inmunoglobulina/sangre , Mieloma Múltiple/terapia , Lesión Renal Aguda/etiología , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/complicacionesRESUMEN
Several prognostic markers, including parameters of tumor burden and cytogenetics, were adopted to identify high-risk patients in multiple myeloma (MM). Recently, the International Staging System (ISS), including beta2-microglobulin (beta2M) and albumin, was introduced for patients with symptomatic MM. As bone disease is a hallmark of MM, we investigated the prognostic impact of the bone resorption marker carboxy-terminal telopeptide of type-1 collagen (ICTP) in combination with ISS, beta2M, albumin, deletion of chromosome 13 and high-dose therapy (HDT) in 100 patients with newly diagnosed symptomatic MM. beta2M alone, albumin alone, ISS, HDT, del(13q14) and ICTP were significant prognostic factors for overall survival (OS). In a multivariate analysis, ICTP was the most powerful prognostic factor (log-rank P<0.001, hazard ratio: ninefold increase). ICTP clearly separated two subgroups with a good and a worse prognosis within each of the three ISS stages (ISS I: P=0.027, ISS II: P=0.022, ISS III: P=0.013). Incorporation of ICTP in a combined ICTP-ISS score significantly (P<0.001) separated four risk groups with a 5-year OS rate of 95, 64, 46 and 22%, [corrected] respectively. These data demonstrate for the first time that the inclusion of the collagen-I degradation product ICTP, as a biomarker of bone resorption, adds to the prognostic value of ISS.
Asunto(s)
Colágeno Tipo I/análisis , Mieloma Múltiple/diagnóstico , Estadificación de Neoplasias/métodos , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/análisis , Resorción Ósea/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/mortalidad , Estadificación de Neoplasias/normas , Péptidos/análisis , Pronóstico , Análisis de SupervivenciaRESUMEN
Wolbachia, a genus of endosymbiotic bacteria of filarial worms, represent novel targets for anti-filarial therapy. The efficacy of compounds against Wolbachia has been evaluated using antiserum raised against the 60 kDa heat shock protein (HSP60) which binds specifically to this protein in both Wolbachia and mitochondria. It has been shown that Wolbachia stains (using such specific probes) stronger than the mitochondria in untreated Onchocerca volvulus, whereas after the depletion of Wolbachia (with drugs) staining of the mitochondria is increased. Herein, immunogold electron microscopy showed that specific anti-HSP60 serum specifically labelled Wolbachia and filarial mitochondria, and that both have distinct localization patterns, thus allowing them to be differentiated. Immunohistochemistry of O. volvulus showed that HSP60 staining is increased in the mitochondria after Wolbachia depletion in the hypodermis, epithelia, muscles, oocytes, embryos, and developing spermatozoa. This could have been the result of the antiserum preferentially binding to the Wolbachia when they are present or due to increased expression of the protein in the absence of the bacteria. To address this, mRNA levels of filarial hsp60 in O. volvulus were measured. After the depletion of Wolbachia, the transcription of hsp60 was significantly greater (7.7 fold) compared with untreated worms. We hypothesize that the increased expression of HSP60 in the absence of Wolbachia is due to a disruption of the homeostasis of the endosymbiosis.
Asunto(s)
Chaperonina 60/biosíntesis , Mitocondrias/metabolismo , Onchocerca volvulus/metabolismo , Onchocerca volvulus/microbiología , Oncocercosis/microbiología , Wolbachia/metabolismo , Animales , Antibacterianos/uso terapéutico , Chaperonina 60/genética , Doxiciclina/uso terapéutico , Femenino , Humanos , Inmunohistoquímica , Ivermectina/uso terapéutico , Masculino , Microscopía Electrónica , Onchocerca volvulus/genética , Oncocercosis/tratamiento farmacológico , Oncocercosis/parasitología , ARN de Helminto/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Simbiosis , Transcripción Genética , Regulación hacia Arriba , Wolbachia/efectos de los fármacos , Wolbachia/aislamiento & purificaciónRESUMEN
Melphalan is associated with severe side effects such as mucositis, diarrhea, and myelosuppression. We investigated how much the individual severity of these side effects is predicted by pharmacokinetics. In addition, we studied glutathione S-transferase GSTM1, GSTT1, and GSTP1 polymorphisms in relation to adverse events. A high interindividual pharmacokinetic variability was observed in 84 patients. There was a linear correlation between creatinine and melphalan clearance (P=0.0004). Patients treated with a dose > or = 70 mg/m(2) had a 23-fold increased risk to develop mucositis (P<0.001) and a 12-fold increased risk to develop diarrhea (P<0.001) compared with lower doses. The GSTP1 codon 105 polymorphism may be relevant for development of mucositis and the GSTT1 deletion may predict diarrhea, but these findings require confirmation. Melphalan-induced side effects were significantly dependent only on dose. Therapeutic drug monitoring or genotyping for GST does not appear to be very helpful in optimizing therapy with melphalan.
Asunto(s)
Glutatión Transferasa/genética , Glutatión Transferasa/metabolismo , Melfalán/efectos adversos , Melfalán/farmacocinética , Adulto , Anciano , Antineoplásicos Alquilantes/administración & dosificación , Antineoplásicos Alquilantes/efectos adversos , Antineoplásicos Alquilantes/farmacocinética , Relación Dosis-Respuesta a Droga , Femenino , Genotipo , Gutatión-S-Transferasa pi/genética , Gutatión-S-Transferasa pi/metabolismo , Humanos , Masculino , Melfalán/administración & dosificación , Persona de Mediana Edad , Polimorfismo GenéticoRESUMEN
In multiple myeloma, the overexpression of receptor activator of nuclear factor kappa B (NF-kappaB) ligand (RANKL) leads to the induction of NF-kappaB and activator protein-1 (AP-1)-related osteoclast activation and enhanced bone resorption. The purpose of this study was to examine the molecular and functional effects of proteasome inhibition in RANKL-induced osteoclastogenesis. Furthermore, we aimed to compare the outcome of proteasome versus selective NF-kappaB inhibition using bortezomib (PS-341) and I-kappaB kinase inhibitor PS-1145. Primary human osteoclasts were derived from CD14+ precursors in presence of RANKL and macrophage colony-stimulating factor (M-CSF). Both bortezomib and PS-1145 inhibited osteoclast differentiation in a dose- and time-dependent manner and furthermore, the bone resorption activity of osteoclasts. The mechanisms of action involved in early osteoclast differentiation were found to be related to the inhibition of p38 mitogen-activated protein kinase pathways, whereas the later phase of differentiation and activation occurred due to inhibition of p38, AP-1 and NF-kappaB activation. The AP-1 blockade contributed to significant reduction of osteoclastic vascular endothelial growth factor production. In conclusion, our data demonstrate that proteasomal inhibition should be considered as a novel therapeutic option of cancer-induced lytic bone disease.
Asunto(s)
Antineoplásicos/farmacología , Resorción Ósea/tratamiento farmacológico , Ácidos Borónicos/farmacología , Mieloma Múltiple/complicaciones , Osteoclastos/efectos de los fármacos , Pirazinas/farmacología , Apoptosis/efectos de los fármacos , Resorción Ósea/etiología , Resorción Ósea/patología , Bortezomib , Diferenciación Celular/efectos de los fármacos , Linaje de la Célula/efectos de los fármacos , Femenino , Compuestos Heterocíclicos con 3 Anillos/farmacología , Humanos , Técnicas In Vitro , Masculino , FN-kappa B/metabolismo , Osteoclastos/citología , Osteoclastos/metabolismo , Piridinas/farmacología , Ligando RANK/metabolismo , Transducción de Señal/efectos de los fármacos , Células Madre/citología , Células Madre/efectos de los fármacos , Factor de Transcripción AP-1/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
The 26S proteasome is a multicatalytic intracellular protease expressed in eukaryotic cells. It is responsible for selective degradation of intracellular proteins that are responsible for cell proliferation, growth, regulation of apoptosis and transcription of genes involved in execution of key cellular functions. Thus proteasome inhibition is a potential treatment option for cancer and diseases due to aberrant inflammation condition. Treatment with proteasome inhibitors results in stabilization and accumulation proteasome substrates, a phenomenon that may result in confounding signals in cells, cell cycle arrest and activation of apoptotic programs. The inhibition of the transcriptional factor nuclear factor kappaB (NF-kappaB) activation was found as one of crucial mechanisms in induction of apoptosis, overcoming resistance mechanisms and inhibition of immune response and inflammation mechanisms. Bortezomib (PS-341) and PS-519 are the first proteasome inhibitors that have entered clinical trials. In multiple myeloma, both the FDA (United States Food and Drug Administration) and EMEA (European Medicine Evaluation Agency) granted an approval for the use of bortezomib (Velcade) for the treatment of relapsed multiple myeloma. At present, several phase II and phase III trials in hematological malignancies and solid tumors are ongoing. PS-519 that focuses on inflammation, reperfusion injury and ischemia is currently under evaluation for the indication of acute stroke.
Asunto(s)
Antineoplásicos/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Neoplasias/tratamiento farmacológico , Neoplasias/enzimología , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma , Animales , Sistemas de Liberación de Medicamentos/tendencias , Humanos , Inhibidores de Proteasas/administración & dosificaciónRESUMEN
Cyclophosphamide (CP), a widely used cytostatic, is metabolized by polymorphic drug metabolizing enzymes particularly cytochrome P450 (CYP) enzymes. Its side effects and clinical efficacy exhibit a broad interindividual variability, which might be due to differences in pharmacokinetics. CP-kinetics were determined in 60 patients using a global and a population pharmacokinetic model considering functionally relevant polymorphisms of CYP2B6, CYP2C9, CYP2C19, CYP3A5, and GSTA1. Moreover, metabolic ratios were calculated for selected CP metabolites, analyzed by (31)P-NMR-spectroscopy. Analysis of variance revealed that the CYP2C19*2 genotype influenced significantly pharmacokinetics of CP at doses
Asunto(s)
Hidrocarburo de Aril Hidroxilasas/genética , Ciclofosfamida/farmacocinética , Oxigenasas de Función Mixta/genética , Adulto , Anciano , Ciclofosfamida/orina , Citocromo P-450 CYP2C19 , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Masculino , Persona de Mediana EdadRESUMEN
HMGI-C belongs to the high-mobility-group-protein (HMG) family of architectural transcription factors and considerable interest has recently been shown in its expression in neoplastic tissues and apparent involvement in tumorigenesis. We could previously demonstrate an expression of HMGI-C mRNA in the peripheral blood of breast cancer patients for the first time. In this prospective study, we evaluated the independent prognostic power of HMGI-C mRNA expression in the peripheral blood of an unselected cohort of 69 patients with metastatic breast cancer using a hemi-nested reverse transcriptase polymerase chain reaction (RT-PCR) followed by sequence analysis of the resulting PCR products. Multivariate analysis was performed using the Cox regression model. HMGI-C mRNA was detected in peripheral blood from 21 out of 69 (30%) patients with metastatic breast cancer. Median survival was 15.9 months in patients expressing HMGI-C, while in the group of patients without HMGI-C expression the median survival had not been reached yet after a median follow-up of 24.7 months and 85.4% were still alive in this group. Disease-specific survival was significantly worse for patients positive for HMGI-C in comparison to those not expressing HMGI-C (P=0.0001). In a multivariate regression analysis, HMGI-C remained an independent prognostic factor for overall survival (P=0.001) besides oestrogen receptor status (P=0.024) and presence of metastases in liver and lungs (P=0.029). HMGI-C expression in the peripheral blood of patients with metastatic breast cancer is a powerful independent indicator for poor overall survival and this is the first study to demonstrate its prognostic relevance in univariate and multivariate analysis.
Asunto(s)
Neoplasias de la Mama/genética , ARN Mensajero/sangre , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/sangre , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Femenino , Estudios de Seguimiento , Humanos , Menopausia , Persona de Mediana Edad , Pronóstico , ARN Mensajero/genética , Análisis de Supervivencia , Factores de TiempoRESUMEN
There is growing evidence that angiogenesis is important not only in solid tumors but also in hematological malignancies. Recently, we found that bone marrow angiogenesis is a prognostic factor for disease-related survival in patients with multiple myeloma. In this report, we addressed the question of whether the microvessel density in bone marrow biopsies is correlated to other myeloma parameters, e.g., serum beta2-microglobulin (beta2-MG) and plasma cell infiltration in the bone marrow. In 22 multiple myeloma patients, immunohistochemical, CD34-stained, paraffin-embedded bone marrow biopsies before and after chemotherapy were studied. Microvessels were counted in 400x magnification, and the mean number of vessels per area in each sample was noted as the microvessel density (MVD). Pretreatment bone marrow MVD (median: 44, range: 11-175 vessels/mm2) correlated significantly with the bone marrow plasma cell infiltration (median: 30%, range: 5-90%, r = 0.642, P=0.001) and beta2-MG (median: 2.74, range: 1.4-26.1 mg/l, r = 0.749, P < 0.0005). In contrast, there was no correlation between posttreatment MVD and plasma cell infiltration or beta2-MG (median: MVD 31, range: 0-221 vessels/mm2, median plasma cell infiltration: 15%, range: 5-80%, r = 0.229, P = 0.306 and median beta2-MG: 2.65, range: 1-27.6 mg/l, r = -0.042, P = 0.853). These findings show that the strong correlations between bone marrow MVD and plasma cell infiltration as well as serum beta2-MG levels disappear after chemotherapy. The underlying mechanisms need further investigations.
Asunto(s)
Médula Ósea/irrigación sanguínea , Mieloma Múltiple/fisiopatología , Neovascularización Patológica , Células Plasmáticas/patología , Microglobulina beta-2/sangre , Biopsia , Médula Ósea/patología , Proteína C-Reactiva/análisis , Calcio/sangre , Estudios de Cohortes , Femenino , Humanos , Inmunoglobulinas/sangre , Masculino , Mieloma Múltiple/patologíaRESUMEN
BACKGROUND AND OBJECTIVES: The differential diagnosis between multiple myeloma (MM) and monoclonal gammopathy of undetermined significance (MGUS) may be uncertain in some cases; this problem is reflected by discrepancies between different classification systems with an accordance in only 2/3 of cases. We studied whether flow-cytometric characteristics of plasma cells (PC) can be used for the differentiation between MGUS and MM. DESIGN AND METHODS: Patients were divided into 3 groups: Group A included 13 myeloma patients with a plasma cell infiltration of the bone marrow of 10-30%, serum M-protein < or = 3.5 g/dL (IgG) or < or = 2 g/dl (IgA) and without bone lesions in conventional radiography. Group B consisted of 53 patients who fulfilled the Durie and Salmon diagnostic criteria including at least one major criterion, and group C individuals with MGUS (n=17). The ratio of immunophenotypically normal (i.e. CD19(+)/CD56(-)) to all bone marrow plasma cells (BMPC), the number of peripheral blood PC (PBPC), the percentage of BMPC in S-phase and the DNA content of BMPC were analyzed. RESULTS: All individuals with MGUS and no patient with MM in group A or group B had a ratio of phenotypically normal to all BMPC > or = 20%. The median of monoclonal PBPC was 0/microL (range 0-2/ microL) in MGUS, 1/microL (range 0-30/microL) in MM group A and 2.4/microL (range 0-211/microL) in MM group B. The median percentage of BMPC in S-phase was 1.6% both in MGUS and in group A and 3% in group B. Aneuploidy was found in 12%, 11% and 41% in MGUS, group A and group B, respectively. INTERPRETATION AND CONCLUSIONS: The ratio of immunophenotypically normal to all BMPC was the only flow-cytometric parameter for the differentiation of MGUS and MM group A (p<0.0005). The other parameters were significantly different between MGUS and MM group B, but not group A.
Asunto(s)
Mieloma Múltiple/diagnóstico , Paraproteinemias/diagnóstico , Células Plasmáticas/inmunología , Células Sanguíneas/patología , Médula Ósea/patología , Estudios de Casos y Controles , Diagnóstico Diferencial , Citometría de Flujo , Humanos , Inmunofenotipificación , Mieloma Múltiple/patología , Paraproteinemias/patología , Células Plasmáticas/patologíaRESUMEN
OBJECTIVE: To quantify nerve fibers and mast cells in human ovaries at different functional stages. DESIGN: Retrospective study. SETTING: Research laboratory of the university. SPECIMEN(S): 8 human ovaries in the follicular (cyclic) phase, 7 polycystic ovaries, and postmenopausal ovaries with (n=5) or without (n=7) hyperthecosis. MAIN OUTCOME MEASURE(S): Single- and double immunohistology for the S100 antigen in glial cells of autonomic nerve fibers, for chymase and tryptase in mast cells, and for the common leukocyte antigen on leukocytes. Histometric evaluation was also performed. INTERVENTION(S): None. RESULT(S): Polycystic ovaries contained significantly more S100-positive nerve fibers in the corticomedullary region than did cyclic ovaries (mean +/- SD per 2-mm(2) area, 476 +/- 136 and 224 +/- 133; P<.01). Postmenopausal ovaries with or without hyperthecosis had the highest density of nerve fibers. In cyclic and polycystic ovaries, more tryptase-positive mast cells than chymase-positive mast cells were found in the interstitial cortex and the medulla. In cyclic ovaries, areas with a moderate density of nerve fibers contained many mast cells. Hence, with increasing nerve fiber density in polycystic ovaries, the number of mast cells decreased strikingly compared with cyclic ovaries (p<.001). Almost no mast cells were seen in postmenopausal ovaries with and without hyperthecosis. The number of leukocyte antigen-positive leukocytes was similar in all groups. CONCLUSION(S): The high density of nerve fibers in polycystic and postmenopausal ovaries, together with a conspicuous decrease in mast cells, indicates altered neuroimmune communication.
Asunto(s)
Mastocitos/patología , Fibras Nerviosas/patología , Ovario/citología , Ovario/patología , Síndrome del Ovario Poliquístico/patología , Posmenopausia , Anciano , Anciano de 80 o más Años , Quimasas , Femenino , Fase Folicular , Humanos , Mastocitos/metabolismo , Persona de Mediana Edad , Fibras Nerviosas/metabolismo , Neuroglía/metabolismo , Enfermedades del Ovario/patología , Ovario/metabolismo , Valores de Referencia , Proteínas S100/metabolismo , Serina Endopeptidasas/metabolismo , Células Tecales/patología , TriptasasRESUMEN
We evaluated the presence and number of eosinophils at varying stages in the human corpus luteum from 27 ovaries of women at reproductive age. Eosinophils preferentially accumulated in dilated microvessels of the thecal layer transforming into septa of the corpus luteum. The granulosa layer under luteinization, the thecal layer, and haemorrhages in the former antrum each contained low, moderate and high numbers of extravasated eosinophils respectively. Eosinophils decreased rapidly during the stages of secretion and regression. Semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) systems were used to investigate the expression and regulation of the eosinophil-attracting chemokines RANTES (regulated on activation, normal T cell expressed and secreted) and eotaxin in granulosa cells obtained from follicular aspirates from women undergoing IVF. Contaminating leukocytes were determined by CD18 mRNA quantification. Granulosa cells expressed RANTES (n = 3; 43 +/- 14 pg/ml, mean +/- SEM). 4ss-phorbol-12-myristate-13-acetate (PMA; 211 +/- 53) and tumour necrosis factor alpha (TNFalpha) (238 +/- 59), but not interleukin (IL)-1 up-regulated RANTES at significant levels. In general, higher basal and stimulated RANTES mRNA and protein were found in cultures with higher CD18 mRNA levels than in those with lower levels. We found only traces of eotaxin mRNA and no eotaxin secretion, even in stimulated granulosa cell cultures, independently of leukocyte levels. Taken together, this is the first study demonstrating the selective presence of eosinophils in human periovulatory structures. RANTES, but not eotaxin, may play an active process in the accumulation of these cells.
Asunto(s)
Quimiocina CCL5/fisiología , Quimiocinas CC , Factores Quimiotácticos Eosinófilos/fisiología , Quimiotaxis de Leucocito , Cuerpo Lúteo/inmunología , Citocinas/fisiología , Eosinófilos/fisiología , Adulto , Células Cultivadas , Quimiocina CCL11 , Quimiocina CCL5/biosíntesis , Quimiocina CCL5/genética , Factores Quimiotácticos Eosinófilos/biosíntesis , Factores Quimiotácticos Eosinófilos/genética , Cuerpo Lúteo/irrigación sanguínea , Cuerpo Lúteo/crecimiento & desarrollo , Citocinas/biosíntesis , Citocinas/genética , Eosinófilos/citología , Femenino , Expresión Génica , Células de la Granulosa , Humanos , Ovulación/fisiología , ARN MensajeroRESUMEN
In a patient with nephrotic syndrome, renal biopsy revealed AL amyloid deposits. Monoclonal lambda light chains were identified in serum and urine. A low percentage of monoclonal plasma cells was detected in the bone marrow. The patient received four cycles of VAD and subsequent high-dose chemotherapy (HDCT) with melphalan (200 mg/m2) followed by autologous peripheral blood stem cell transplantation. Proteinuria rapidly diminished during chemotherapy. Three months after HDCT, the patient has no edema, and no signs of plasma cell dyscrasia are currently detectable. Using VAD before starting HDCT may improve the condition of patients with amyloidosis and reduce transplantation-related morbidity and mortality.
Asunto(s)
Amiloidosis/complicaciones , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trasplante de Células Madre Hematopoyéticas , Melfalán/uso terapéutico , Síndrome Nefrótico , Terapia Combinada , Dexametasona/uso terapéutico , Doxorrubicina/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Síndrome Nefrótico/etiología , Síndrome Nefrótico/fisiopatología , Síndrome Nefrótico/terapia , Recurrencia , Trasplante Autólogo , Vincristina/uso terapéuticoRESUMEN
In crucial cases the diagnosis of non-Hodgkin's lymphoma (NHL) still represents a challenge to the pathologist since morphological criteria do not always help to distinguish between reactive and malignant lymphoproliferations. Clonality assays are a useful supplement since monoclonal cell proliferation is strong evidence for malignancy. The polymerase chain reaction (PCR) can be utilized to establish the clonal origin of B- or T-cell lymphocyte populations by amplification of rearranged immunoglobulin and T-cell receptor (TCR) genes. In the present study DNA was isolated from a variety of neoplastic and nonneoplastic formalin-fixed, paraffin-embedded lymph nodes (n = 62), cutaneous tissue (n = 9), samples of miscellaneous origin (n = 11), and reported here for the first time, decalcified bone marrow samples (n = 35). These samples were submitted to PCR-based assays directed against the immunoglobulin heavy-chain (IgH), immunoglobulin kappa light-chain (IgL kappa), and TCR gamma chain genes. The impact of various decalcifying agents on the ability to amplify DNA was investigated by PCR-based amplification of a single copy gene. Buffered and nonbuffered EDTA was found not to impede amplification of DNA fragments up to 300 bp in length. In lymph node and cutaneous specimens monoclonality was detected in 83% of B-NHL cases using a seminested PCR approach for the amplification of IgH, whereas the same approach gave rise to monoclonal bands in 80% of bone marrow samples. The subsequent amplification of IgL kappa helped to raise the sensitivity of detection to 94%. Monoclonality was detected in seven of nine T-cell NHLs by amplification of TCR gamma.(ABSTRACT TRUNCATED AT 250 WORDS)