Preclinical modeling of myelodysplastic syndromes.

Myelodysplastic syndromes (MDS) represent a heterogeneous group of hematological clonal disorders. Here, we have tested the bone marrow (BM) cells from 38 MDS patients covering all risk groups in two immunodeficient mouse models: NSG and NSG-S. Our data show comparable level of engraftment in both models. The level of engraftment was patient specific with no correlation to any specific MDS risk group. Furthermore, the co-injection of mesenchymal stromal cells (MSCs) did not improve the level of engraftment. Finally, we have developed an in vitro two-dimensional co-culture system as an alternative tool to in vivo. Using our in vitro system, we have been able to co-culture CD34+ cells from MDS patient BM on auto- and/or allogeneic MSCs over 4 weeks with a fold expansion of up to 600 times. More importantly, these expanded cells conserved their MDS clonal architecture as well as genomic integrity.

Phase I study of high-dose topotecan with haematopoietic stem cell support in the treatment of ovarian carcinomas: the ITOV 01 protocol.

Topotecan has demonstrated activity in ovarian carcinomas. In order to increase the tumour response rate and to define the maximum tolerated dose (MTD) of topotecan, we decided to develop a high-dose phase I regimen supported by stem cell support. High-doses schedules using a 1-day single administration have MTDs of 10.5 (24 h continuous infusion (CI)) or 22.5 mg/m2 (30 min infusion). Five-day CI induces grade IV mucositis at high doses (MTD<12 mg/m2). We chose to administer topotecan in a 5-day schedule with a 30 min daily infusion. Patients were scheduled to receive one cycle of therapy. The first dose level was 4.0 mg/m2/day x 5 days. Limiting toxicities were defined as toxic death, grade IV non-haematopoietic or haematopoietic toxicity >6 weeks. From August 1998 to April 2002, 49 patients were included. Forty-three patients have completed one course and 15 have received two cycles. One patient treated at level 7 mg/m2/day died of sepsis. Median duration of grade IV neutropenia was 9 days. Two episodes of grade IV diarrhoea were observed at level 9.5 mg/m2/day. Pharmacokinetic data were linear within the dose range of 4-9.0 mg/m2/day. The MTD was reached at 9 mg/m2/day x 5 days.

Are angiogenic factors, cytokines, and soluble adhesion molecules prognostic factors in patients with renal cell carcinoma?

Angiogenesis has an important role in the progression of solid tumors. Therefore, we measured the blood levels (ELISA) of angiogenic factors [basic fibroblast growth factor (bFGF), hepatocyte growth factor/scatter factor, and vascular endothelial growth factor (VEGF)] and soluble adhesion molecules [E-selectin, intercellular adhesion molecule (ICAM-1), platelet endothelial cell adhesion molecule-1, and vascular cell adhesion molecule-1] in 76 consecutive patients with untreated renal cell carcinoma and 41 healthy controls to evaluate their prognostic value. The serum levels of bFGF, hepatocyte growth factor, and VEGF were significantly higher in patients with renal cancer than they were in healthy subjects. bFGF and VEGF values were significantly higher in patients with disseminated cancer (N+ and/or M+) than they were in those with undisseminated (M-N-) cancer: median = 27 pg/ml, range = 5-118, n = 15 versus median = 8 pg/ml, range = 1-149, n = 61 (P = 10(-4)) for bFGF; and median = 883 pg/ml, range = 200-2317, n = 15 versus median = 278 pg/ml, range = 0-1704, n = 61 (P = 0.006) for VEGF. The blood levels of ICAM-1 and vascular cell adhesion molecule-1 were significantly higher, and the levels of E-selectin and platelet endothelial cell adhesion molecule-1 were significantly lower in patients with renal cancer than they were in controls. Plasma ICAM-1 was higher in metastatic patients (M+) than they were in nonmetastatic (M-) patients: median = 687 ng/ml, range = 294-1091, n = 12 versus median = 408 ng/ml, range = 217-1375, n = 64 (P = 10(-4)). ICAM-1 and bFGF blood values were correlated with the size of the primary tumor. The interleukin 6 and tumor necrosis factor-alpha (TNF-alpha) values of these patients have been previously published and are included in the survival analysis. Univariate analysis showed that bFGF, ICAM-1, interleukin 6, and TNF-alpha, before treatment, were prognostic factors. In multivariate analysis for proportional hazard regression, only TNF-alpha was an independent prognostic indicator, with a normal plasma TNF-alpha being highly predictive for a good prognosis in patients with untreated renal cell carcinoma.

Are basic fibroblast growth factor and vascular endothelial growth factor prognostic indicators in pediatric patients with malignant solid tumors?

Angiogenesis plays an important role in the growth, progression, and metastasis of solid tumors. Among angiogenic factors, basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) appear to be useful markers in adults with cancer. The aim of this pilot study was to determine the levels of VEGF in serum and bFGF in serum and urine of children with solid tumor at diagnosis (as measured by ELISA), and to investigate whether these parameters provide prognostic information. Forty consecutive patients with different types of cancer were prospectively included in this study. Median values of all studied angiogenic factors were higher in patients than in controls (n = 40), and the differences were statistically significant for bFGF in serum and urine: 10 versus 3 pg/ml (P = 0.0004) and 6406 versus 0 pg/g of creatinine (P < 0.0001), respectively. Among patients, median serum values of bFGF and VEGF were higher in children with metastatic disease (n = 14) than in those with localized disease (n = 26). The difference was statistically significant for serum bFGF: 17.5 versus 6 pg/ml (P = 0.02). Serum angiogenic factor levels correlated with outcome. The estimated event-free survival at 3 years was 79% for patients with normal bFGF values (n = 13) versus 42% (n = 26; P = 0.02) for those with high levels, and 71% in case of normal VEGF values (n = 20) versus 38% (n = 19; P = 0.04) for those with high levels. No benefit of normal urinary bFGF values was observed. Our results provide a rationale for exploring the clinical interest of bFGF and VEGF measurements in body fluids of a larger group of children with cancer.

Immunocytochemical study of a Ca(2+)-ATPase enzyme in the human megakaryocytic lineage.

We report the presence of a Ca(2+)-ATPase in human megakaryocytes (MK) using an immunofluorescence technique on bone marrow smears and especially on normal MK progenitors in culture. This finding is based on the comparative staining of MK with 1) a well-characterized antibody raised against purified rabbit skeletal sarcoplasmic reticulum Ca(2+)-ATPase, 2) antibody P2 raised against the glycoprotein IIb-IIIa complex as a marker of megakaryocytic lineage, and 3) anti-glycophorin A as a marker of erythroid lineage. On bone marrow smears, all cells recognized by P2 were also labeled with the anti-Ca(2+)-ATPase antibody. In culture, a maximum number of MK colonies was observed at day 11. From days 2-4, some MK precursors appeared stained both with the anti-Ca(2+)-ATPase and P2 antibodies; other cells were reactive with both anti-Ca(2+)-ATPase and anti-glycophorin A antibodies. From day 5 of culture, cells were either simultaneously stained with P2 and anti-Ca(2+)-ATPase antibodies or with anti-glycophorin A antibody, but not with the anti-Ca(2+)-ATPase antibody. Besides this first evidence of an early expression of a Ca(2+)-ATPase in MK, this work provides a useful tool for identification of MK by immunofluorescence.

Tumour necrosis factor-alpha, interleukin-1 beta and interleukin-6 in patients with renal cell carcinoma.

Patients with renal cell carcinoma (RCC) can exhibit fever, weight loss and increases in acute phase proteins. Interleukin (IL)-1, tumour necrosis factor (TNF) and IL-6 are considered major mediators of local and systemic inflammation. We measured plasma IL-1 beta, TNF-alpha (immunoradiometric assay) and IL-6 (ELISA) in 78 consecutive patients with untreated RCC and in 56 normal subjects. IL-6 plasma levels were higher in patients with RCC (mean 24.2 pg/ml, 11.1-37.3, 95% confidence interval) than in normal subjects (11.6 pg/ml, 10.1-13.1, n = 39, P < 0.01). The patients with fever or weight loss had higher blood levels of IL-6. IL-6 blood levels were also higher in patients with lymph node invasion and/or distant metastases (94.7 pg/ml, 39.0-150.4, n = 15) than in patients with undisseminated RCC (7.4, 4.1-10.7, n = 63, P < 0.0001). An abnormal IL-6 plasma value (> 40 pg/ml) had a positive predictive value of 91.0% for lymph node and/or metastatic spread of RCC. IL-6 was statistically correlated with C-reactive protein (nephelometric assay) blood values r' = 0.67, n = 78, P < 0.001). The TNF-alpha and IL-1 beta levels were not significantly different in patients with or without fever or weight loss. The plasma levels of the three cytokines were not correlated with the size of the primary tumour. An increased plasma value of IL-6 is a good marker for tumour dissemination in patients with untreated RCC.

Studies of portal hemodynamics and hepatic oxygen consumption during acute liver allograft rejection.

Hemodynamics and oxygen variables, plasma cytokines, and histological features of a liver tissue sample obtained by transvenous biopsy were evaluated during 65 episodes of acute rejection. The hepatic venous pressure gradient was significantly higher in patients with acute rejection than in those without (5.1+/-0.3 vs. 3.1+/-0.2 mmHg, P<0.01). The increase in pressure gradient was related to the severity of rejection lesions. Hepatic blood flow was significantly lower in patients with than in those without acute graft rejection (1.28+/-0.11 vs. 1.75+/-0.13 L/min, P<0.05). Plasma interleukin-6 levels were significantly increased in patients with acute rejection and positively correlated with pressure gradient values. In patients with acute rejection, a significant decrease in hepatic venous oxygen content (-16%) was associated with a significant increase in hepatic oxygen consumption (+24%), whereas hepatic oxygen transport did not change significantly. In treated patients with a favorable response, the pressure gradient decreased significantly by 46%, but it remained elevated in patients who later developed chronic graft rejection. In conclusion, this study confirms that acute graft rejection may induce an increase in portal pressure, which is related to the severity of rejection lesions. It also shows that acute rejection decreases hepatic blood flow and increases hepatic oxygen consumption. In addition, it suggests that the hepatic venous pressure gradient might be useful to determine the outcome of rejection.

Childhood-onset systemic lupus erythematosus: antiphospholipid antibodies in 37 patients and their first-degree relatives.

OBJECTIVE: Antiphospholipid antibodies (aPL) are noted with increased frequency in patients with systemic lupus erythematosus (SLE). The main manifestations found to be associated with aPL are arterial and venous thrombotic events, thrombocytopenia, and recurrent pregnancy loss. This study is an attempt to define the incidence of aPL in patients with childhood-onset SLE and in their relatives and to correlate their presence with clinical manifestations, and especially, to evaluate the risk of thrombosis in aPL-positive subjects. METHODOLOGY: We studied 37 unrelated patients and 107 of their first-degree relatives. VDRL, IgG and IgM anticardiolipin, and IgG antiphosphatidylethanolamine antibodies were studied in all probands during periods of clinical remission and in first-degree relatives at the time of interview. Lupus anticoagulant had only been studied in probands during an SLE flare-up. RESULTS: Thirty-eight percent of probands and 19% of relatives were positive for at least one aPL, with little overlap between the different aPL studied. -No aPL-negative proband developed thrombosis. Two of the aPL-positive probands had thrombotic events before testing, and a third one showed thrombosis after testing. Only two probands had high levels of IgG aCL and showed thrombosis. The occurrence of aPL positivity in relatives was not always related to its presence in probands. None of the aPL-positive relatives had had thrombosis, but recurrent fetal loss was noted in one aPL-positive mother with SLE. Although there was a high frequency of SLE, SLE-like disease, auto-immune disorders or positive serological findings for lupus in first-degree relatives, many of these relatives did not test positive for aPL. CONCLUSION: The high levels of IgG aCL may be considered a risk factor for thrombosis. Findings in relatives suggest a multifactorial origin for autoimmune disease and antibody production.

Human platelet suspension stimulates porcine retinal glial proliferation and migration in vitro.

PURPOSE: To characterize the cellular and molecular mechanisms underlying the efficacy of autologous platelet suspension adjuvant therapy in the treatment of macular hole. METHODS: Platelet suspensions were: paid from whole blood samples obtained from informed volunteers. For proliferation assays, platelet suspensions or purified growth factors were added to semi-confluent cultures of porcine real glial cells for 24 hours, followed by [3H]thymidine for 15 hours, after which time cells were washed, solubilized, and counted for uptake of radioactive tracer. For cell migration assays, confluent glial cultures were scrape wounded and maintained in the presence or absence of platelet suspension or identified platelet constituents. Cell migration into the denuded area was scored as a function of time. In certain cases, specific pharmacologic inhibitors of growth factor action were added at the same time as platelet adjuvant or growth factors. RESULTS: Platelet suspension adjuvant induced strong mitogenic and chemotactic responses in cultured glia, in a dose-dependent manner. Maximal incorporation of thymidine was two- to threefold that of control levels, with an ED50 approximately 5 x 10(6) platelets/ml, and migration was enhanced up to 80-fold after 48 hours. Platelet suspension-induced proliferation was completely blocked by addition of 25 microM genistein, a tyrosine kinase receptor inhibitor. However, the same concentration only partially blocked the cell migration response. Addition of any single growth factor or protein identified from ELISA analysis, or a combination of all factors, did not significantly stimulate proliferation or cell migration. CONCLUSIONS: Human platelet suspensions exert both proliferative and chemotactic influences on retinal glial cells in vitro, suggesting that the same responses may occur in platelet-induced macular hole repair in humans. Growth factors or proteins that have been identified within the suspensions do not mimic these responses in vitro, implying that additional currently unidentified trophic activities are also present.

Levels of portal and systemic blood cytokines after colectomy in patients with carcinoma or Crohn's disease.

BACKGROUND: Cytokine overproduction has been observed in different pathophysiologic conditions, including sepsis, carcinoma, inflammatory disease, and tissue injury induced by operation. Colectomy is a procedure that may result in excessive cytokine release through the portal vein. The respective effects of an operative procedure, perioperative septic complications, and of the disease itself on cytokine production are still not known. STUDY DESIGN: This study was done to investigate the variations in the levels of interleukin-1 beta (IL-1), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha) and C-reactive protein (CRP) in portal and systemic blood during and after colectomy in patients with malignancy or with Crohn's disease. Blood samples were collected intraoperatively from portal and systemic veins of 24 patients undergoing colectomy for either Crohn's disease (n = 13) or carcinoma (n = 11), and postoperatively (from days 1 to 5) from systemic veins. The changes in blood levels of cytokines and CRP in patients with an uneventful colectomy (n = 19) were compared to changes in patients whose colectomy was complicated by sepsis (n = 5). Similar changes in cytokines and CRP levels were compared between patients with malignancy and those with Crohn's disease. RESULTS: The portal and systemic blood levels of IL-1, IL-6, TNF-alpha, and CRP were significantly correlated before and after colectomy. In portal blood, the level of IL-6 was significantly higher after colectomy than before. In systemic blood, the levels of CRP, TNF-alpha, and IL-6 before colectomy were significantly higher in patients with Crohn's disease than in patients with malignancy. After uneventful colectomy, a temporary increase in CRP, TNF-alpha, and IL-6 was noted in systemic blood, followed by a rapid decrease, although systemic blood cytokine levels remained significantly higher after colectomy complicated by sepsis. Interleukin-1 beta levels in both portal and systemic blood remained unchanged during and after colectomy, regardless of the indication for operation and its outcome. CONCLUSIONS: Colectomy causes acute release of cytokines and CRP in both the portal and systemic circulation. The increase in IL-6 observed after colectomy in portal blood and subsequently in systemic blood suggests local production from the resected specimen, or at least from the area of resection. Cytokine production, especially of IL-6, was modified not only by the underlying disease itself, as higher levels were observed in Crohn's disease before colectomy, but also by the presence of perioperative septic complications.

Endothelial cell dysfunction secondary to the adhesion of diabetic erythrocytes. Modulation by iloprost.

We previously showed the correlation between the extent of vascular complications and erythrocyte adherence to endothelium in diabetes mellitus. The accumulation of advanced glycation end products (AGEs) on the erythrocyte surface in diabetes mediates their interaction with endothelial cells through a specific endothelial receptor for AGEs (RAGE). Binding of diabetic erythrocytes to endothelial cells resulted in evidence of oxidant stress responsible for a range of cellular perturbations. In the present study, we have investigated the effect of iloprost, a prostacyclin analog, on several activities modified by diabetic erythrocyte-endothelium interaction: 1) generation of oxidant stress based on production of thiobarbituric acid reactive substances (TBARS: control: 2.37 +/- 0.32 versus iloprost: 1.39 +/- 0.005 mumol/10(11) cells), 2) alteration of the endothelial barrier function as measured by an increase permeability to 125I-albumin (control: 13.31 +/- 0.85 versus iloprost: 9.45 +/- 0.7 10(-7) cm/s) of the endothelial cell monolayer, 3) modification of the endothelial cell function showed by an increase in interleukin-6 release (control: 21.66 +/- 3.11 versus iloprost 15.45 +/- 0.76 ng/10(6) cells). The increase in permeability to albumin as well ass TBARS production and interleukin-6 release were inhibited by iloprost (10(-8)-10(-6) mol/l) treatment in a dose-dependent fashion. These results indicate that erythrocyte associated AGEs might alter endothelial cell function. The perturbations can be limited in vitro by iloprost.

[Contact factors in severe sepsis]. / Facteurs de contact au cours des états septiques graves.

Coagulation and fibrinolysis are not activated in an isolated system but it involves numerous interrelations with the kininogen-kinin pathway and the complement. In severe sepsis, substances released by microorganisms, notably lipopolysaccharides, can activate the contact system, and particularly in such circumstances, contact activation probably plays a role in the occurrence of haemodynamic changes and consumption coagulopathy. Evidence of kininogen-kinin pathway activation as assessed by biological investigations in patients with severe sepsis, could lead to the therapeutical use of natural or synthetic protease inhibitors.

[Importance of bFGF ("basic fibroblast growth factor") for diagnosis and treatment of hemangiomas]. / Intérêt du dosage du bFGF ("basic Fibroblast Growth Factor") pour le diagnostic et le traitement des hémangiomes.

OBJECTIVES: Hemangiomas of infancy follow a characteristic three-phases course: proliferation, involution, regressed Proliferative endothelial cells predominate during the proliferative phase. Moreover it has been shown that patients with active angiogenesis have elevated levels of urinary bFGF (basic Fibroblast Growth Factor). PATIENTS AND METHODS: Here we report our preliminary results of urinary bFGF assay (ELISA) for the diagnosis and follow up of severe hemangioma. We also assayed bFGF in normal infants, in patients with large vascular malformations and in infants with Kasabach-Merritt syndrome. RESULTS: In the control group, urinary bFGF was elevated in new borns but nul or very low in infants. Urinary bFGF levels were normal, i.e. very low in 4 patients with a vascular malformation. In infants with a clinically proliferative hemangioma, urinary bFGF was elevated in 8 among the 10 studied. bFGF levels guided treatment in 9 patients. Urinary bFGF was elevated in 4 patients with Kasabach-Merritt syndrome. DISCUSSION: Angiogenesis is regulated by angiogenic and inhibitory factors. The angiogenic factor bFGF is an autocrine growth factor for endothelial cells and hemangioma endothelial cells expressing bFGF in their cytosol during the proliferative phase. As suggested by J. Folkman and his group, assay of urinary bFGF appears useful in differentiating between hemangioma and vascular malformation and for follow up of treated patients.

[Kasabach-Merritt syndrome of the leg associated with osteolysis or Gorham sign]. / Syndrome de Kasabach-Merritt d'un membre associé à une ostéolyse ou signe de Gorham.

INTRODUCTION: Kasabach-Merritt syndrome and Gorham's sign are two uncommon and severe, sometimes life-threatening, complications in infants with vascular lesions. Their association has been described in rare cases. CASE REPORT: An infant with a vast congenital angiomatous lesion including an extensive lymphatic component, developed active regional osteolysis then suddenly suffered disseminated intravascular coagulation of the leg. Medical treatment was unsatisfactory. After unsuccessful use of low molecular weight heparin, pentoxifyllin and alpha interferon, amputation of the leg was required to avoid a fatal outcome. DISCUSSION: Kasabach-Merritt syndrome does not develop on classic immature hemangiomas, despite some contradictory statements in the literature. In our case, a complex tumor developed in association with a lymphatic malformation. The association of Kasabach-Merritt syndrome with osteolysis (Gorham's sign) does not appear to be fortuitous. Therapeutic management of these severe complications is difficult and requires case by case analysis.

[Kasabach-Merritt syndrome on a congenital tufted angioma]. / Syndrome de Kasabach-Merritt sur angiome en touffes congénital.

INTRODUCTION: Kasabach-Merritt syndrome is a very rare disease of infancy, with profound thrombocytopenia and a mild to severe consumption coagulopathy; this biological phenomenon is difficult to control. CASE REPORT: A 1-month old boy had a congenital plaque-like lesion in the calf. It was a biopsy-proven tufted angioma. Five weeks later, Kasabach-Merritt syndrome developed. After failure of ticlopidine + aspirin, and oral betamethasone treatment, thrombocytopenia was cured with vincristine treatment, then the leg lesion slowly continued to shrink after cessation of the treatment. It had disappeared before the age of 1 year. DISCUSSION: We highlighted two points: 1) Kasabach Merritt does not appear as a complication of a classic hemangioma (infantile, "cellular", "capillary", involuting-type), as it has long been thought. In our experience, it develops on a different endothelial cell proliferation, in this case a congenital tufted angioma, but it can also engraft on a kaposiform hemangioendothelioma. 2) These patients are difficult to treat because, up to now, no single treatment has given constant by good results. Vincristine was recently introduced in the treatment of Kasabach-Merritt syndrome, with excellent, rapid outcome. CONCLUSION: What seems a therapeutic progress in a difficult field needs further control.