Endocan or endothelial cell specific molecule-1 (ESM-1): a potential novel endothelial cell marker and a new target for cancer therapy.

Endocan, previously called endothelial cell specific molecule-1, is a soluble proteoglycan of 50 kDa, constituted of a mature polypeptide of 165 amino acids and a single dermatan sulphate chain covalently linked to the serine residue at position 137. This dermatan sulphate proteoglycan, which is expressed by the vascular endothelium, has been found freely circulating in the bloodstream of healthy subjects. Experimental evidence is accumulating that implicates endocan as a key player in the regulation of major processes such as cell adhesion, in inflammatory disorders and tumor progression. Inflammatory cytokines such as TNF-alpha, and pro-angiogenic growth factors such as VEGF, FGF-2 and HGF/SF, strongly increased the expression, synthesis or the secretion of endocan by human endothelial cells. Endocan is clearly overexpressed in human tumors, with elevated serum levels being observed in late-stage lung cancer patients, as measured by enzyme-linked immunoassay, and with its overexpression in experimental tumors being evident by immunohistochemistry. Recently, the mRNA levels of endocan have also been recognized as being one of the most significant molecular signatures of a bad prognosis in several types of cancer including lung cancer. Overexpression of this dermatan sulphate proteoglycan has also been shown to be directly involved in tumor progression as observed in mouse models of human tumor xenografts. Collectively, these results suggest that endocan could be a biomarker for both inflammatory disorders and tumor progression as well as a validated therapeutic target in cancer. On the basis of the recent successes of immunotherapeutic approaches in cancer, the preclinical data on endocan suggests that an antibody raised against the protein core of endocan could be a promising cancer therapy.

Phenotypic analysis of CD34 subpopulations in normal human bone marrow and its application for the detection of minimal residual disease.

In the past, studies on CD34+ cells have been based on the use of monoclonal antibodies conjugated with different fluorochromes that show different fluorescence intensity and yield variable results. Moreover, most of these studies have neither specifically focused on adult human BM samples nor have they used combinations to explore specifically the phenotype of myeloid committed CD34+ cells. The aim of the present study has been to characterize the normal human CD34+ precursor cells from adult BM in order to identify missing or extremely rare phenotypes that can be used for detecting minimal residual disease (MRD) in patients with AML. For this purpose we have utilized the fluorochrome conjugates that provide the most sensitive signals for identifying low antigenic expression, and the technique has been adapted to the characterization of cells present at very low frequencies. Normal human BM samples from 13 adult healthy volunteers have been analyzed using triple stainings at flow cytometry. The mean percentage of CD34+ cells detected was 0.72 +/- 0.33%; these cells displayed an heterogeneous light-scatter distribution. Most CD34+ cells coexpressed CD38 (96.7 +/- 5.7%), HLADR (81.6 +/- 14.0%), CD33 (84.7 +/- 18.3%), CD13 (84.6 +/- 16.2%) and CD71 antigens (65.5 +/- 9.1%). In addition, almost half of CD34+ cells were CD117+ (60 +/- 26.8%). Only a small proportion of CD34+ cells coexpressed CD4 (15.5 +/- 11.7%, CD36 (31.7 +/- 6.2%), CD61 (16.3 +/- 12.9%), CD41 (6.5 +/- 5.5%) or the lymphoid associated markers CD10 (18.6 +/- 11.8%) and CD19 (12.3 +/- 13.2%). Reactivity for the CD15 antigen was observed in a small population of CD34+HLADR+ cells (11.6 +/- 11.2%) although its intensity of expression was lower than that of the more mature granulocytic cells. No CD34+ cells displayed CD14, CD65, CD20, strong CD22, CD3 and CD56 antigens. Accordingly, most adult bone marrow CD34+ cells appeared to be committed to the myeloid lineage (CD13+/CD33+) and displayed an intermediate-to-large FSC/SSC while the lymphoid-committed CD34+ cells (CD19+, CD10+) were in a minority with low FSC/SSC values. By triple marker stainings several phenotypes of CD34+ precursor cells were found to be either undetectable or present at very low frequencies (< 1 x 10(-3)) in the normal human adult bone marrow. These data may be of great value for defining leukemia 'associated' phenotypes used to detect minimal residual disease in adult acute leukemia patients.

Expression of NK and lymphoid-associated antigens in blast cells of acute myeloblastic leukemia.

In the present study, the expression of two NK-associated antigens (CD56 and CD16) together with six 'classically' considered lymphoid-related markers (TDT,CD19,CD10,CD7,CD2,CD4) has been analyzed by appropriate dual combinations in 265 acute myelogenous leukemia (AML) patients. Among the lymphoid markers, CD4 and CD7 were those most frequently expressed by AML blast cells (58% and 21.6%, respectively) while the incidence of positivity for the other markers was lower: CD19 (7.8%), CD10 (10.9%), CD2 (11.4%), and TDT (11.3%). Regarding NK-associated antigens, CD56 was present in 41% of AML cases analyzed whereas CD16 was detected in only 23%. All but one of the CD16+ cases coexpressed the CD56 antigen. The expression of these antigens was not associated with the degree of cell differentiation assessed either by morphological or immunophenotypical criteria, with the exception of the correlation observed between monocytic leukaemias and the expression of the CD4, CD56, and CD16 antigens. Regarding the prognostic value of the markers investigated, CD56 expression was associated with a tendency for a better outcome whereas CD7 was the only antigen that had an adverse influence on the survival of AML patients.

Phenotypic changes in acute myeloid leukaemia: implications in the detection of minimal residual disease.

AIM: To explore the role of phenotypic changes as possible limiting factors in the immunological detection of minimal residual disease in patients with acute myeloid leukaemia (AML). METHODS: 20 relapses were evaluated, with special attention to changes in the criteria used for the definition of a phenotype as "aberrant". In all cases the same monoclonal antibody and fluorochrome were used at diagnosis and in relapse. RESULTS: Six out of the 16 patients showed aberrant phenotypes at diagnosis. At relapse, no changes in the aberrant phenotypes were detected in most of the patients; nevertheless, in two of the four patients with asynchronous antigen expression this aberration disappeared at relapse. At diagnosis in both cases there were already small blast cell subpopulations showing the phenotype of leukaemic cells at relapse. Ten out of the 16 cases analysed showed significant changes in the expression of at least one of the markers analysed. CONCLUSIONS: At relapse in AML the "leukaemic phenotypes" usually remained unaltered, while other phenotypic features--not relevant for distinguishing leukaemic blast cells among normal progenitors--changed frequently; however, they were not a major limitation in the immunological detection of minimal residual disease.

Inflammatory molecule release by beta-amyloid-treated T98G astrocytoma cells: role of prostaglandins and modulation by paracetamol.

Deposition of beta-amyloid in the brain triggers an inflammatory response which accompanies the neuropathologic events of Alzheimer's disease and contributes to the destruction of brain tissue. The present study shows that beta-amyloid can stimulate human astrocytoma cells (T98G) to secrete the proinflammatory factors interleukin-6 and prostaglandins. Furthermore, prostaglandins can stimulate T98G to secrete interleukin-6, which in turn triggers the formation of additional prostaglandins. Prostaglandins are, therefore, a key element in the induction and maintenance of a state of chronic inflammation in the brain which may exacerbate the fundamental pathology in Alzheimer patients. Paracetamol (0.01-1000 microM), an unusual analgesic/antipyretic drug which acts preferentially by reducing prostaglandin production within the central nervous system, and indomethacin (0.001-10 microM) caused a clear dose-dependent reduction of prostaglandin E2 production by stimulated T98G cells whereas interleukin-6 release was not affected. These data provide further evidence of the involvement of non-steroidal anti-inflammatory drugs in the inflammatory processes that can be generated by glial cells in intact brain.

Effect of the subchronic treatment with the acetylcholinesterase inhibitor heptastigmine on central cholinergic transmission and memory impairment in aged rats.

The effect of subchronic administration of the acetylcholinesterase (AChE) inhibitor heptastigmine (HEP 0.6 mg/kg s.c. daily for 15 days) was investigated on cortical extracellular acetylcholine (ACh) levels and on memory function in aged male rats (26 months old at the beginning of the experiments) using microdialysis and behavioural techniques. Twenty-four hours after the last treatment, cortical ACh levels were significantly higher in rats subchronically treated with HEP than in rats treated with saline and AChE activity was still inhibited in cortex, hippocampus and striatum. The injection of a challenge dose of HEP (0.6 mg/kg s.c.) 24 h after the last treatment produced a faster and a more sustained increase of ACh in the cortex of subchronically treated rats compared to those repeatedly injected with saline. However, the maximum increase of ACh levels after injection of the challenge was comparable in both groups. In an object recognition test in which the pretest and test phase were spaced by 45 days, HEP prevented the deterioration of spatial memory occurring during this period, but had no effect on non-spatial memory. The present results suggest that moderate inhibition of brain AChE is able to maintain high levels of cortical extracellular ACh in aged rats and that this increase matches facilitatory effect of HEP on spatial memory.

Adenosine triphosphate affects interleukin -1beta release by T98G glioblastoma cells through a purinoceptor-independent mechanism.

T98G glioblastoma cells were previously shown to significantly increase interleukin-1beta (IL-1beta) mRNA levels in response to IL-1beta stimulation. This work demonstrates that in such conditions T98G, despite possessing biologically active interleukin converting enzyme, do not release detectable amounts of IL-1beta, even in the presence of 20 mM adenosine triphosphate (ATP). IL-1beta secretion is observed only following concomitant stimulation with 1000 units/ml of IL-1beta and 20 mM ATP. ATP induces a dose-dependent depolarization of T98G plasma membrane, whereas it does not affect Ca(2+) concentration or cell membrane permeability. Our data, together with the observation that the depolarizing effects of ATP are retained after preincubation with 100 microM suramin, an antagonist of P2-purinoceptors, suggest that ATP plays a role in IL-1beta secretion by T98G but its effects do not occur through P2-purinoceptors.

Development and pharmacological characterization of a modified procedure for the measurement of carbonic anhydrase activity.

Carbonic anhydrases (CAs) are a family of zinc metalloenzymes of molecular mass 30-60 kDa; seven different isoenzymes belong to this family (Okuyama et al., 1992, Proc Natl Acad Sci USA 89:1315-1319). They may be broadly recognized according to the efficiency with which they catalyze the reversible interconversion of CO2 and HCO3-, and they differ in physicochemical properties, in sensitivity to various inhibitors and in their subcellular localization; cytoplasmic (CA I, CA II, CA III, and CA VII), cell-surface membrane (CA IV), and mitochondrial (CA V) and secretory (CA VI) isoenzymes have been described. Several methods are reported in the literature for the measure of CA enzymatic activity; they may be broadly divided into two categories: those based on the measure of pH variation (pH-stat and colorimetric assays) (Wu et al., 1993, J Ocular Pharm 9:97-108; Maren, 1991, Molec Pharmacol 41:419-426) and the ones in which CO2 production is measured through pCO2 sensors (Botrè and Botrè, 1990, Anal Biochem 185:254-264).

Treatment with bindarit, an inhibitor of MCP-1 synthesis, protects mice against trinitrobenzene sulfonic acid-induced colitis.

OBJECTIVE: Chemokines play a fundamental role in trafficking and activation of leukocytes in colonic inflammation. We investigated the ability of bindarit, an inhibitor of monocyte chemoattractant protein-1 (MCP-1/CCL2) synthesis, to inhibit chemokine production by human intestinal epithelial cells (HT-29) and its effect in trinitro-benzene sulfonic acid (TNBS)-induced colitis in mice. MATERIALS AND METHODS: HT-29 cells were incubated with bindarit in the presence of TNF-alpha/IFN-gamma and 24 h later supernatants were collected for MCP-1, IL-8 and RANTES measurement. A 1 mg enema of TNBS was given to BALB/c mice, and bindarit (100 mg/kg) was orally administered twice daily starting from two days before colitis induction. Weight loss, histology, and MCP-1 level and myeloperoxidase (MPO) activity in colon extracts were assessed. RESULTS: In HT-29 cells, bindarit concentration-dependently and selectively inhibited MCP-1 secretion (as well as mRNA expression) primed by TNF-alpha/IFN-gamma. Moreover treatment with bindarit reduced clinical and histopathological severity of TNBS-induced colitis. These effects were associated with significant inhibition of MCP-1 and MPO in colon extracts. CONCLUSIONS: Bindarit exhibits a potent bioactivity in reducing leukocyte infiltration, down-regulating MCP-1 synthesis, and preventing the development of severe colitis in a mice model of TNBS-induced colitis. These observations suggest a potential use of MCP-1 synthesis blockers in intestinal inflammation in humans.

Benzydamine protection in a mouse model of endotoxemia.

OBJECTIVE: Previous studies have shown that benzydamine (40 mg/kg s.c.) is able to inhibit tumor necrosis factor (TNF) production and to reduce mouse lethality when administered before or concomitantly with LPS. The present study was designed to further investigate benzydamine activity against LPS-induced toxicity in terms of potency and therapeutic effects. METHODS: Female Balb/c mice were used. A dose-response curve of animal lethality versus endotoxin dose was performed (LD50 = 45 micrograms/mouse). Therapeutic effects were studied selecting the dose of LPS to achieve an LD100 (160 micrograms/mouse). Mortality was assessed daily and mice were followed for 8 days. The potential mode of action of therapeutically administered benzydamine was also investigated. TNF alpha and IL-1 beta levels were measured, at 5 h after LPS injection, both in sera and in lungs. Moreover, the drug was assayed in a TNF-dependent cytoxicity test. RESULTS: Benzydamine, administered at 20 mg/kg s.c. simultaneously with the endotoxin, significantly increased LPS LD50 up to 230 micrograms/mouse (p < 0.05). Moreover, the drug significantly protected mice against LPS-induced lethality when administered either 30 min or 4 h after endotoxin injection (p < 0.001). Benzydamine, therapeutically administered at 20 mg/kg s.c., significantly reduced TNF alpha and IL-1 beta production induced by LPS both in serum and lungs and it was shown to inhibit TNF-dependent cytoxicity on L929 cells. CONCLUSIONS: These results clearly demonstrate the therapeutic activity of benzydamine in a simple model of endotoxic shock. Available data confirm the potential role of benzydamine as an anti-cytokine agent and provide suggestions for novel therapeutic applications of this anti-inflammatory drug.

[Convulsions during treatment of acute lymphoblastic leukemia in children]. / Crisi convulsive durante il trattamento per leucemia linfoblastica acuta nel bambino.

BACKGROUND: The prevalence of seizures in children with acute lymphoblastic leukemia (ALL) varies between 3 and 13% depending on the various studies, whereas it is 1% in the general population aged under 15 years etiopathogenesis and outcome of seizures in children during treatment for ALL. METHODS: A retrospective study was carried out in 204 children with a consecutive diagnosis of ALL, 89 females and 115 males, aged between 5 months and 17 years and 11 months, diagnosed between 15-4-1988 and 15-4-1998, and treated at the Division of Pediatric Oncology and Pediatric Hematology of Turin University using three successive generations of AIEOP protocols 88 (48 cases), 91 (86 cases) and 95 (70 cases). Observation of the patients in the study ended on 30-9-1998. The criteria for eligibility were those stated in the respective protocols. Seizures were classified using the international classification; the diagnosis was made if a doctor, a nurse or a reliable relative witnessed the event with confirmation by the consultant neurologist. RESULTS: Twelve out of 204 (5.8%) patients in this series presented seizures: 2 out of 48 cases using protocol 88 (4.1%), 6 out of 86 cases using protocol 91 (6.9%) and 4 out of 70 cases using protocol 95 (5.7%). None of the patients had critical episodes or other significant neurological pathologies prior to the onset of ALL, nor had they been affected by leukemic meningosis or undergone cranial radiotherapy. When evaluating the possible etiology, the authors noted that, except for one case of febrile convulsion, the seizures in the remaining patients could be attributed to the toxicity of chemotherapy. With regard to the evolution of seizures, only one patient died, whereas the others showed no neurologic sequelae. CONCLUSIONS: The frequency of seizures in children receiving treatment for ALL in the series analysed here is in line with that reported in the literature. Neurotoxicity caused by chemotherapy appears to be the main etiopathogenetic factor.

Benzydamine inhibits the release of tumor necrosis factor-alpha and monocyte chemotactic protein-1 by Candida albicans-stimulated human peripheral blood cells.

Benzydamine is a non-steroidal antiinflammatory drug, devoid of activity on arachidonic acid metabolism, which is extensively used as a topical drug in inflammatory conditions, particularly for the treatment of bacterial vaginosis and Candida albicans-sustained vaginitis. In the present study the effects of benzydamine on the production of several inflammatory cytokines were examined in cultures of Candida albicans-stimulated human mononuclear cells. Benzydamine (6.25-50 microM) inhibited Candida-induced tumor necrosis factor-alpha and, to a lesser extent, interleukin-1 beta production, whereas it did not affect interleukin-6 release. Benzydamine also blocked monocyte chemotactic protein-1 secretion, but it did not affect interleukin-8 production. Unlike benzydamine, ibuprofen and naproxen, two non-steroidal antiinflammatory drugs also used topically, were unable to suppress inflammatory lymphokine production from Candida-activated mononuclear cells. These data suggest that benzydamine may be effective in local Candida infections at least in part by suppressing inflammatory cytokine and monokine production in the vaginal mucosa and consequently decreasing their levels in vaginal secretions.

Anemia aplásica adquirida en niños: seguimiento durante 14 años / Acquired aplasica anemia in chilcren: fourteen year folow up

Durante 14 años fueron tratados 24 pacientes (pts) con anemia aplásica adquirida (AAA), pre-escolares (6), escolares (11) y adolescentes (7); rango: 2-16 años. Siete del Distrito Capital. Etiología: idiopática 19/24 (79 por ciento), secundaria 5/24 (21 por ciento). Se clasificaron según severidad en: moderada 2/24 (21 por ciento). Se clasificaron según severidad en: moderada 2/24 (8 por ciento), severa 17/24 (71 por ciento) y muy severa 5/24 (21 por ciento). En 16 pts se realizó estudio HLA, 4(25 por ciento) tuvieron donante compatible, en 3 se realizó Trasplante de Médula Osea (TMO). Seguimiento promedio 62 meses. Ciclosporina (CsA) + Corticoesteroides (CtS) 10/24, Remisión Completa (RC) 5/10 (50 por ciento), Remisión Parcial (RP) 1/10 (10 por ciento), Ausencia Remisión (AR) 4/10 (40por ciento); CsA + Globulina antitimocito (ATG) 11/24: RC 4/11 (36,36 por ciento), RP: 4/11 (36,36 por ciento), AR: 3/11 (27,27 por ciento); TMO: 3/24, RC: 100 por ciento; La respuesta terapéutica global fue: 12/24 pts alcanzaron RC (50 por ciento), 5/24 RP (20.83 por ciento) y 6/24 AR (25 por ciento). Evolución clonal se presentó en 3 pts (12 por ciento). El promedio de sobrevida a los 5 años de seguimiento resultó en 70 por ciento para el grupo que recibió CsA + ATG y 58 por ciento para el grupo CsA + Cts., p= 0.28. La sobrevida global a los 5 años fue de 69 por ciento. La AAA idiopática es la etiología más frecuente en el niño y las formas severas y muy severas de la enfermedad representan el 92 por ciento de los casos. La inmunosupresión (IS) es un tratamiento efectivo en pts. que no disponen de donante para TMO. El tratamiento de IS combinado CsA + ATG resultó superior al uso de CsA ++ Cts. Creación de un grupo Cooperativo Nacional para el estudio y tratamiento de la AAA