Ofer Kaplan

Management of Breast Fibroadenomas

OBJECTIVE: To identify from the literature and clinical experience a rational approach to management of fibroadenomas of the breast.METHOD: Recent literature on detection, diagnosis, and natural history of fibroadenomas was reviewed. Experience with over 4,000 women evaluated in the breast clinic at the Tel-Aviv Medical Center contributed to the management strategies suggested by review of the literature.RESULTS: Fibroadenomas of the breast are common, accounting for 50% of all breast biopsies performed. Physical examination, sonography, and fine needle aspiration are effective in distinguishing fibroadenomas from breast cancer. Transformation from fibroadenoma to cancer is rare; regression or resolution is frequent, supporting conservative approaches to follow-up and management.CONCLUSION: Age-based algorithms that allow for conservative management and that limit excision to patients whose fibroadenomas fail to regress are presented.

Octreotide Treatment in Patients with Severe Acute Pancreatitis

We investigated the effect of octreotide in the treatment of severe acute pancreatitis in a case–control study. Experimental and clinical studies on the effect of octreotide in the treatment of acute pancreatitis have shown controversial results. Since January 1992, we have been conducting a prospective randomized study on the effect of octreotide in severe acute pancreatitis, in three hospitals in Israel. The entering criteria included three or more of the Ranson prognostic signs and CT findings of severe pancreatitis. Patients were randomly assigned to conservative treatment either with or without octreotide (0.1 mg subcutaneously three times a day). The end points of the study included: complication rate (ARDS, sepsis, renal failure, pseudocyst, fistula, and abscess), length of hospital stay, and mortality. From January 1992 to December 1996, 60 patients entered the study. After evaluating the files, 10 patients were excluded due to failure to meet the entering criteria, incomplete data, or incorrect diagnosis. Of the remaining 50 patients, 25 were assigned to octreotide (treatment group) and 25 to conservative treatment only (control group). The two groups matched with regard to age, sex, etiology, and severity of the disease. The complication rate was lower in the treatment group with regard to sepsis (24% vs 76%, P = 0.0002) and ARDS (28% vs 56%, P = 0.04). The hospital stay was shorter in the treatment group (20.6 vs 33.1 days, P = 0.04). Two patients died in the treatment group and eight in the control group (P < 0.019). These results suggest that octreotide may have a beneficial effect in the treatment of severe acute pancreatitis.

Information from combined 1H and 31P NMR studies of cell extracts: Differences in metabolism between drug-sensitive and drug-resistant MCF-7 human breast cancer cells

Combined analysis of both 1H and 31P NMR spectra of extracts of drug-sensitive and multidrug-resistant MCF-7 human breast cancer cells enabled quantitative comparisons between the concentrations of major metabolites, as well as of their precursors. In resistant cells high energy phosphorus compounds, phosphocreatine and ATP, and also their precursors, creatine and ADP, were elevated compared to the sensitive cells. In phospholipid metabolism, the sensitive cells showed higher phosphocholine and phosphoethanolamine concentrations than the resistant cells, but choline levels were similar. These results delineated the differences in control of metabolic pathways between drug-sensitive and drug-resistant cells.

Fas ligand enhances hematopoietic cell engraftment through abrogation of alloimmune responses and nonimmunogenic interactions

Early after transplantation, donor lineage‐negative bone marrow cells (lin− BMC) constitutively upregulated their expression of Fas ligand (FasL), suggesting an involvement of the Fas/FasL axis in engraftment. Following the observation of impaired engraftment in the presence of a dysfunctional Fas/FasL axis in FasL‐defective (gld) donors or Fas‐defective (lpr) recipients, we expressed a noncleavable FasL chimeric protein on the surface of donor lin− BMC. Despite a short life span of the protein in vivo, expression of FasL on the surface of all the donor lin− BMC improved the efficiency of engraftment twofold. The FasL‐coated donor cells efficiently blunted the host alloimmune responses in primary recipients and retained their hematopoietic reconstituting potential in secondary transplants. Surprisingly, FasL protein improved the efficiency of engraftment in syngeneic transplants. The deficient engraftment in lpr recipients was not reversed in chimeric mice with Fas− stroma and Fas+ BMC, demonstrating that the host marrow stroma was also a target of donor cell FasL. Hematopoietic stem and progenitor cells are insensitive to Fas‐mediated apoptosis and thus can exploit the constitutive expression of FasL to exert potent veto activities in the early stages of engraftment. Manipulation of the donor cells using ectopic FasL protein accentuated the immunogenic and nonimmunogenic interactions between the donor cells and the host, alleviating the requirement for a megadose of transplanted cells to achieve a potent veto effect.

Metabolism of breast cancer cells as revealed by non-invasive magnetic resonance spectroscopy studies

The basis for the use of nuclear magnetic resonance (NMR) spectroscopy as a tool to study the metabolism of breast cancer cells is described. The differences between proton (1H), carbon (13C), and phosphorus (31P) NMR methods is explained, and the techniques of cell extracts, cell suspensions and perfusion methods for cells are detailed. In order to perfuse cells they are preferably trapped in a gel matrix, either in the form of a thread or a bead. The gel must have appropriate properties that enables efficient oxygenation and availability of nutrients and drugs. The metabolic effects of perfusion of breast cancer cells with nutrients, drugs, and hormones are reported, and the clinical relevance of these results and methods are outlined.

Concerning antisense inhibition of the multiple drug resistance gene.

Recently, Vasanthakumar and Ahmed reported (Vasanthakumar, G.; Ahmed, N.K., Cancer Communications 1:225-232; 1989) a complete inhibition of the multiple drug resistance gene (MDR1) in the K562/III erythroleukemia cells, using a 15 bases-long methylphosphonate oligodeoxynucleotide analog. The sequence used, however, contained three mismatches relative to the corresponding fragment of the human MDR1 gene and, hence, the results reported cannot at present be regarded as a classical antisense effect. We have made attempts to inhibit the expression of the MDR1 gene in MCF-7 human breast cancer cells selected for resistance to Adriamycin using phosphorothioate analogs of oligodeoxynucleotides. Studies with model 35S-labeled-phosphorothioates indicated poor uptake of the compounds into the cells; the radioactivity was located mainly in the soluble fraction (cytoplasm), but membranes and the nuclear fraction were also labeled. Unmodified oligodeoxynucleotides were toxic to the cells, whereas the phosphorothioates were not. The MDR1 inhibition with phosphorothioates was studied by measuring their effects on adriamycin toxicity and by immunocytochemical titration of P170. Elevation of adriamycin cytotoxicity consistent with a decreased drug resistance was observed with one antisense sequence, but the immunocytochemical assay indicated only slight inhibition of the synthesis of P170. In the wild type (drug sensitive) MCF-7 cells phosphorothioates decreased adriamycin toxicity in a sequence-independent manner. The results indicate that the effects of antisense oligodeoxynucleotides on cells are complex. Computer simulation of the secondary structure of MDR1 mRNA indicated not only extensive folding but, also, the presence of many regions not involved in intramolecular hybridization, which are of potential interest as targets for antisense oligodeoxynucleotides.

Monitoring the transport and phosphorylation of 2‐deoxy‐D‐glucose in tumor cells in vivo and in vitro by 13C nuclear magnetic resonance spectroscopy

We describe the use of 2‐deoxy‐D‐[6‐13C]glucose to follow simultaneously, by 13C NMR, both transport and phosporylation to its 6‐phosphate form, in MCF‐7 breast cancer cells in vitro and in vivo in subcutaneous tumors in nude mice.

Tumor Necrosis Factor Receptors Support Murine Hematopoietic Progenitor Function in the Early Stages of Engraftment

Tumor necrosis factor (TNF) family receptors/ligands are important participants in hematopoietic homeostasis, in particular as essential negative expansion regulators of differentiated clones. As a prominent injury cytokine, TNF‐α has been traditionally considered to suppress donor hematopoietic stem and progenitor cell function after transplantation. We monitored the involvement of TNF receptors (TNF‐R) 1 and 2 in murine hematopoietic cell engraftment and their inter‐relationship with Fas. Transplantation of lineage‐negative (lin−) bone marrow cells (BMC) from TNF receptor‐deficient mice into wild‐type recipients showed defective early engraftment and loss of durable hematopoietic contribution upon recovery of host hematopoiesis. Consistently, cells deficient in TNF receptors had reduced competitive capacity as compared to wild‐type progenitors. The TNF receptors were acutely upregulated in bone marrow (BM)‐homed donor cells (wild‐type) early after transplantation, being expressed in 60%–75% of the donor cells after 6 days. Both TNF receptors were detected in fast cycling, early differentiating progenitors, and were ubiquitously expressed in the most primitive progenitors with long‐term reconstituting potential (lin−c‐kit+ stem cell antigen (SCA)‐1+). BM‐homed donor cells were insensitive to apoptosis induced by TNF‐α and Fas‐ligand and their combination, despite reciprocal inductive cross talk between the TNF and Fas receptors. The engraftment supporting effect of TNF‐α is attributed to stimulation of progenitors through TNF‐R1, which involves activation of the caspase cascade. This stimulatory effect was not observed for TNF‐R2, and this receptor did not assume redundant stimulatory function in TNFR1‐deficient cells. It is concluded that TNF‐α plays a tropic role early after transplantation, which is essential to successful progenitor engraftment. STEM CELLS 2010;28:1270–1280

Gangrene of the lower limbs in diabetic patients: A malignant complication

Diabetic foot lesions are a common medical problem with major socioeconomic impact. Gangrene is usually a late and sometimes fatal complication. A series of 118 diabetic patients who underwent amputation of the lower limb at our institution over a 10 year period has been presented. Forty-two patients underwent amputation of the toes or part of the foot, 48 underwent below-knee amputation, and 18 underwent above-knee amputation. In 24 (20.3 percent), the necrotic process advanced postoperatively and necessitated additional amputation. The average hospital stay was 33.6 days. Twenty-eight patients (23.7 percent) died during the postoperative period, and the main cause of death was sepsis. Patients who presented with extensive gangrene had a higher mortality rate. There was no correlation between mortality and the duration of conservative treatment, number of repeated operations, the treatment of diabetes before hospitalization, onset of symptoms, or status of the peripheral pulses. The solution to the problem is early and vigorous preventive treatment. This could be accomplished through highly specialized clinics within the community.

NMR Studies of Metabolism of Cells and Perfused Organs

This chapter documents the application of NMR spectroscopic methods to studies of the metabolism of cells and perfused organs. Progress in this area is attested to by the sheer number of publications. This area of research stands alone, as a means of shedding light on the metabolism and pharmacology of cells and organs, but also exists as a basis for the applications of NMR spectroscopic methods to in vivo and clinical situations. Methods of obtaining cellular extracts are included, but the bulk of the chapter is devoted to the methods that have been developed to obtain spectra from intact cells perfused in the NMR tube. Such methods as embedding in gels, use of microcarrier beads, hollow fibers, and spheroids are described and compared. Most of this work involves 31P-NMR, but some 13C-NMR tracer studies are also reported. A section is also devoted to the consideration of proton NMR as a means to monitor metabolism, and the necessity of not only suppressing the water signal, but also of removing all signals of extracellular origin, which has recently been accomplished. Finally some work on perfused organs is described and collated into a table that could prove useful for the reader. The question arises as to the relevance of the results with perfused organs relative to those in vivo. As clinical spectroscopy develops, future work must address this question.