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Local treatment with surgery and radiotherapy gives unsatisfactory results in patients with locally advanced cancer. In many cases distant metastases appear shortly after the removal of the primary tumor. Selecting breast cancer as a model for locally advanced disease, we are extrapolating our findings to other solid tumors. Neoadjuvant chemotherapy has improved survival of these patients by downstaging the primary tumors allowing local treatment and early elimination of distant micrometastases. We recently reported in this journal on a study of 42 patients with locally advanced breast cancer (LABC) who received prolonged neoadjuvant chemotherapy of doxorubicin, cyclophosphamide, and GM‐CSF prior to surgery and postoperative radiotherapy. These results were promising and prompted us to initiate an international randomized phase III study in which either six neoadjuvant cycles or three neoadjuvant cycles plus three adjuvant cycles are being compared. In LABC patients treated with six neoadjuvant chemoimmunotherapy cycles, we observed a significant rise in the dendritic cell content of the axillary tumor‐draining lymph nodes after therapy, associated with an encouraging disease free survival and overall survival. We hypothesize that the prolonged presence of draining lymph nodes in combination with the repeated tumor antigen release, dendritic cell recruitment, and activation may account for the observed increased survival of LABC patients. Based on our findings and the results of preclinical studies, we hypothesize that it is more effective to administer chemotherapy in an extended neoadjuvant regimen, taking advantage of the concurrent biological and immunological processes in the primary tumor and its draining lymph nodes.

We report the immunomodulatory effects of an intravenous treatment with F(ab')2 fragments of the bispecific monoclonal antibody BIS-1 during subcutaneous recombinant interleukin 2 (rIL-2) therapy of renal cell cancer (RCC) patients. BIS-1 is directed against both the CD3 antigen on T cells and the EGP-2 molecule on carcinoma cells and some normal epithelia. The amount of BIS-1 F(ab')2 bound to peripheral blood lymphocytes (PBLs) increased dose-dependently. This occupation degree was highest at the end of the 2 h infusion and rapidly decreased subsequently. During the first hour of BIS-1 F(ab')2 infusion the number of PBLs decreased slowly. This was followed by an increase in serum tumour necrosis factor alpha (TNF-alpha) concentrations and a rapid decrease in the numbers of peripheral blood lymphocytes, monocytes and eosinophils. In our view, the most likely explanation for the observed decrease in occupation degree of BIS-1 F(ab')2 and the rise in TNF-alpha levels is based on the assumption that BIS-1-carrying T cells leave the circulation. The CD3 antigens on these extravasated T cells become cross-linked by EGP-2 antigens, inducing TNF-alpha secretion. This results in an enhanced decrease in the numbers of PBLs, monocytes and eosinophils. These preliminary results suggest that BIS-1 F(ab')2 treatment during IL-2 therapy may induce local T-cell activation.

Initial studies have shown that recombinant human interleukin-6 (rhIL- 6) induces anemia. Until now, the pathophysiologic mechanism of this induced anemia has been unknown. To unravel the underlying mechanism, we examined 15 cancer patients receiving rhIL-6 as an antitumor immunotherapy in a phase II study. rhIL-6 was administered subcutaneously at 150 micrograms once daily for 6 consecutive weeks. Various hematologic and biochemical parameters were measured weekly during rhIL-6 treatment and 4 weeks after rhIL-6 discontinuation. To determine plasma volume and red blood cell (RBC) volume, radioisotope dilution assays with labeled autologous RBCs and with human serum albumin were performed before rhIL-6 administration and on day 8 of rhIL-6 therapy. Hemoglobin levels decreased (mean change +/- SE) 7% +/- 1.5% within 3 days after the start of rhIL-6 therapy (P < .0001) and 19% +/- 2% at week 4. Levels had normalized at follow-up. The plasma volume increased 18% +/- 5% during the first week of rhIL-6 administration (P < .003), whereas RBC volume remained unaffected. The mean RBC corpuscular volume remained unchanged for 2 weeks and then began to decrease slowly, reaching its nadir at week 6 (5% +/- 1%; P < .01). Serum iron levels decreased 65% +/- 12% at week 4 (P < .002) and then returned to initial baseline values. Erythropoietin levels increased rapidly up to 68% at week 3 (P < .0001) and had normalized 4 weeks after rhIL-6 therapy. Levels of serum albumin, prealbumin, and transferrin decreased (P < .0001, P < .003, and P < .0001, respectively), whereas levels of serum amyloid A (P < .003), C-reactive protein, haptoglobin, and alpha-1-antitrypsin (P < .0001) increased during rhIL-6 treatment. All levels returned to pretreatment values after discontinuation of rhIL-6. No alterations in reticulocyte counts, serum lactic dehydrogenase levels, and bilirubin levels were observed. A 6-week regimen of subcutaneous rhIL-6 results in a rapid dilution anemia, caused by an acute and significant increase in plasma volume and followed by hypoferremia. This anemia is reversible after the cessation of rhIL-6 treatment.

In a phase I trial the toxicity and immunomodulatory effects of combined treatment with intravenous (i.v.) bispecific monoclonal antibody BIS-1 and subcutaneous (s.c.) interleukin 2 (IL-2) was studied in renal cell cancer patients. BIS-1 combines a specificity against CD3 on T lymphocytes with a specificity against a 40 kDa pancarcinoma-associated antigen, EGP-2. Patients received BIS-1 F(ab')2 fragments intravenously at doses of 1, 3 and 5 micrograms kg-1 body weight during a concomitantly given standard s.c. IL-2 treatment. For each dose, four patients were treated with a 2 h BIS-1 infusion in the second and fourth week of IL-2 therapy. Acute BIS-1 F(ab')2-related toxicity with symptoms of chills, peripheral vasoconstriction and temporary dyspnoea was observed in 2/4 and 5/5 patients at the 3 and 5 micrograms kg-1 dose level respectively. The maximum tolerated dose (MTD) of BIS-1 F(ab')2 was 5 micrograms kg-1. Elevated plasma levels of tumour necrosis factor alpha (TNF-alpha) and interferon gamma (IFN-gamma) were detected at the MTD. Flow cytometric analysis showed a dose-dependent binding of BIS-1 F(ab')2 to circulating T lymphocytes. Peripheral blood mononuclear cells (PBMCs), isolated after treatment with 3 and 5 micrograms kg-1 BIS-1, showed increased specific cytolytic capacity against EGP-2+ tumour cells as tested in an ex vivo performed assay. Maximal killing capacity of the PBMCs, as assessed by adding excess BIS-1 to the assay, was shown to be decreased after BIS-1 infusion at 5 micrograms kg-1 BIS-1 F(ab')2. A BIS-1 F(ab')2 dose-dependent disappearance of circulating mononuclear cells from the peripheral blood was observed. Within the circulating CD3+ CD8+ lymphocyte population. LFA-1 alpha-bright and HLA-DR+ T-cell numbers decreased preferentially. It is concluded that i.v. BIS-1 F(ab')2, when combined with s.c. IL-2, has a MTD of 5 micrograms kg-1. The treatment endows the T lymphocytes with a specific anti-EGP-2-directed cytotoxic potential.

Malignant peripheral nerve sheath tumors (MPNST) are rare. They account for 10% of all soft tissue sarcomas. The incidence of MPNST in patients with neurofibromatosis type 1 (NF-1) is 4%. A retrospective study was undertaken to evaluate the prognosis of patients with MPNST and NF-1 vs patients with MPNST alone. Twenty-two patients with MPNST were diagnosed. The MPNST was diagnosed with NF-1 in 11 patients (50%). Treatment was defined as curative in 20 patients (90%), non-curative in one patient (5%), and one patient received no treatment. The median disease-free survival (DFS) was 14 months (range 0-153 months). The median overall survival 24 months (range 1-153 months). There were three patients with isolated local failures (14%), four patients with local and distant failures (18%), and seven patients with isolated distant failures (32%). There was no statistical difference between patients with and without NF-1. Five patients with NF-1 developed a second MPNST (45%), none of the patients without NF-1 did (P = 0.018). A statistically worse survival was found when the duration of the first symptoms had been longer than six months. Patients with MPNST have a poor prognosis with a high risk for local and distant failures (>50%). There is no statistical difference in the final outcome for MPNST with or without NF-1, but patients with NF-1 have a high risk for developing a second MPNST.

The usual preparation of raney nickel catalysts W-21), W-5, and W-62)involves a tedious and time-consuming wasning process with distilled water to remove the last traces of salts. we found that this demineralication can more conveniently be accomplished with ion-exchange resin. The procedures described below have been inuse for several years a our laboratory, where large quantities of Raney Nickel are needed for desulfurization and hydrogenation experiments.

Cyclization reaction of the dithiols (I), (IV), and (VI) with the dichloroisobutene (II) is promoted by cesium carbonate to produce the macrocyclic exo‐methylene thioethers (III), (V), and (VII).

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