Adhesive interactions between haemopoietic progenitor cells and bone marrow sinusoidal endothelium are potentially important in the homing of these cells back to the extravascular compartment of the ...marrow to re-establish haemopoiesis following stem cell transplantation. A simple method for the isolation and culture of human bone marrow endothelial cells is described using bone marrow aspirates obtained from patients undergoing bone marrow harvests for autologous or syngeneic bone marrow transplantation. The method is based on the selective binding of the lectin Ulex europaeus agglutinin-1 (UEA-1) to endothelial cells. Magnetic Dynabeads coupled with UEA-1 were incubated with single cell suspensions of bone marrow following red cell lysis, and bound cells were isolated with a magnet. The isolated cells demonstrated positive immunofluorescence staining for von Willebrand factor. Cells were plated onto tissue culture flasks coated with extracellular matrix derived from human umbilical vein endothelial cells in an endothelial serum-free medium together with 5% fetal calf serum for 24 h. Cells were then cultured in endothelial serum-free growth medium supplemented with 5% fetal calf serum, endothelial cell growth supplement and heparin. After 2-4 weeks in culture, two morphologically different cell populations can be identified. One has a polygonal spindle-shaped morphology with a rapid growth rate, the other a rounded morphology and a slow growth rate. Both populations have a vesiculated cytoplasm. Positive immunostaining of the cells was demonstrated with a number of endothelial cell markers including von Willebrand factor, and antibodies to ICAM-1, VCAM-1, E-selectin, CD31 and BMA120. Weibel-Palade bodies were observed by electron microscopy. Culture of these cells will allow detailed in vitro studies of adhesion mechanisms in the homing of haemopoietic progenitor cells.
To investigate the results of treatment and factors that affect prognosis in adult patients undergoing high-dose therapy and autologous bone marrow transplantation (ABMT) for lymphoblastic lymphoma ...(LBL).
The study was a retrospective analysis of 214 patients reported to the Lymphoma Registry of the European Group for Bone Marrow Transplantation (EBMT) between January 1981 and December 1992, including 105 patients undergoing marrow transplantation in first complete remission (CR). Data on all patients were reviewed, and analysis of prognostic factors conducted.
The actuarial overall survival rate at 6 years for the entire group is 42%. Disease status at ABMT was the major determinant of outcome: 6-year actuarial overall survival was 63% for patients transplanted in first CR, compared with 15% for those with resistant disease at the time of transplantation. Transplantation in second CR resulted in a 31% rate of actuarial overall survival at 6 years. For patients transplanted in first CR, univariate analysis failed to identify any factors at presentation that predicted for outcome after transplantation.
These results suggest that ABMT is effective therapy for adults with LBL, even in patients with disease that is resistant to conventional-dose therapy. Results for patients transplanted in second CR are superior to those reported for conventional-dose salvage regimens. The results in first CR require verification in a prospective randomized clinical study.
This multicenter, prospective, randomized controlled trial compared the efficacy and toxicity of two chemotherapy regimens in advanced Hodgkin's lymphoma (HL): the weekly alternating Stanford V and ...the standard, twice-weekly regimen of doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD).
Patients had stage IIB, III, or IV disease or had stages I to IIA disease with bulky disease or other adverse features. Radiotherapy was administered in both arms to sites of previous bulk (> 5 cm) and to splenic deposits, although this was omitted in the latter part of the trial for patients achieving complete remission (CR) in the ABVD arm. A total of 520 patients were randomly assigned and were assessed for the primary outcome measure of progression-free survival (PFS). Five hundred patients received protocol treatment, and radiotherapy was administered to 73% in the Stanford V arm and to 53% in the ABVD arm.
The overall response rates after completion of all treatment were 91% for Stanford V and 92% for ABVD. During a median follow-up of 4.3 years, there was no evidence of a difference in projected 5-year PFS and overall survival (OS) rates (76% and 90%, respectively, for ABVD; 74% and 92%, respectively, for Stanford V). More pulmonary toxicity was reported for ABVD, whereas other toxicities were more frequent with Stanford V.
In a large, randomized trial, the efficacies of Stanford V and ABVD were comparable when given in combination with appropriate radiotherapy.
Despite the widespread clinical exploitation of HPC mobilization and homing, the mechanisms central to these two phenomena are still unknown. However, the evolving concepts of multi-step adhesion ...cascades and demonstration of intracellular signalling which links lectin/carbohydrate binding with integrin activation in HPCs and other leucocytes suggests that HPC homing may be analogous to leucocyte homing in other systems. The complexity of this system is apparent from the data presented above, and more sensitive methods need to be developed to dissect the various adhesion pathways which may be involved.
We used flow cytometry to characterize cell adhesion molecule expression of the human haemopoietic cell lines KG1a, K562, HL‐60, NALM‐6 and CEM. A 51chromium labelling assay was used to study the ...adhesion of these cell lines to extracellular matrix components and to bone marrow stromal and endothelial cultures. Both adhesion molecule expression and functional binding behaviour varied between cell lines. All five cell lines expressed the integrins α4β1 and α5β1 and all adhered to fibronectin. However, differences in intensity of expression of these integrins failed to correlate with extent of fibronectin adhesion. Inhibition experiments demonstrated that adhesion of KG1a to fibronectin was completely inhibited by divalent cation chelation and partially inhibited by RGDS peptides and chondroitinase ABC, suggesting that both α4β1 and α5β1 as well as CD44 were responsible for this interaction. Adhesion to bone marrow stromal and endothelial layers was superior to that to purified extracellular matrix components and was partially inhibited by divalent cation chelation. RGD peptides and anti‐α4 monoclonal antibody also partially inhibited KG1a adhesion to bone marrow endothelium.
Discordance between cell adhesion molecule expression and adhesive behaviour suggest that current phenotypic descriptions remain incomplete and reinforce the need for complementary functional binding studies.
The clinical applicability of the Revised European-American Lymphoma (R.E.A.L.) Classification has been demonstrated in several retrospective studies. The present, ongoing study was initiated to ...evaluate the clinical and pathological utility of the R.E.A.L. Classification compared with the Working Formulation (WF) in a prospective fashion, in an unselected patient population treated at a single institution.
Prospective data were collected on 596 biopsies from 557 patients referred with an initial diagnosis of lymphoma. After initial histologic review, 465 biopsies from 441 patients were confirmed as non-Hodgkin's lyphoma (NHL), 412 of which could be classified in R.E.A.L. and WF.
According to WF criteria, 25% were low grade, 58% intermediate grade and 2% high grade, 14% could not be allocated to a WF subtype. According to R.E.A.L., 46% were diffuse large B cell, 19% follicle centre lymphoma, 6% marginal zone, 6% small lymphocytic, 4% mantle cell, and 3% T-cell anaplastic large cell. For those with B-cell NHL, 7% were unclassifiable in WF compared with 1% in R.E.A.L. Corresponding figures for T-cell NHL were 68% and 3%, respectively.
Preliminary results confirm the clinical utility of the R.E.A.L. Classification in a single institution setting, demonstrating that cases were more readily sub-typed in R.E.A.L. compared with WF. Frequencies are comparable with I.L.S.G. data. Further follow up with large patient numbers is on-going to analyse survival data with reference to clinical prognostic factors.
A MESSAGE FROM ASCO's PRESIDENT For the second consecutive year, the American Society of Clinical Oncology (ASCO) is publishing Clinical Cancer Advances: Major Research Advances in Cancer Treatment, ...Prevention, and Screening, an annual review of the most significant cancer research presented or published over the past year. ASCO developed this report to demonstrate the enormous progress being made on the front lines of cancer research today. The report is intended to give all those with an interest in cancer care-the general public, cancer patients and physicians, policymakers, oncologists, and other medical professionals-an accessible summary of the year's most important cancer research advances. These pages report on new targeted therapies that are improving survival and response rates in hard-to-treat cancers such as kidney cancer, HER-2-positive breast cancer, head and neck cancer, and chronic myelogenous leukemia; the FDA's approval of the world's first preventive vaccine for human papillomavirus (HPV), which has the potential to dramatically reduce the global burden of cervical cancer; and advances in the fast-growing field of personalized medicine, including a new lung cancer test that could help physicians better target treatments and predict prognosis. These advances are only part of the landscape. Survival rates are on the rise, the number of cancer deaths in the United States began declining for the first time since 1930, and new research is showing that the rates of certain common cancers, such as those of the breast and colon, have stabilized, and may have even begun to decline. However, cancer research still faces a number of major obstacles. At a time of extraordinary scientific potential, declining federal funding of cancer research threatens to stall or even reverse recent progress. Such funding cuts have already led to fewer clinical trials, fewer talented young physicians entering the field, and a growing bottleneck of basic science discoveries waiting to be "translated" into useful therapies and diagnostics. In addition to highlighting the major research advances over the past year, this report also identifies key barriers to accelerating the pace of cancer research and outlines ASCO's recommendations for overcoming them. Despite these and other challenges, there is much good news on the front lines of cancer research. This report demonstrates the essential role of clinical cancer research in finding new and better ways to treat, diagnose, and prevent a group of diseases that strike half of men and one-third of women in the United States.
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