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Biomedical subjects

M Weil

Publications and source records attributed to M Weil.

At least 55 records · Page 3Linked to original sources
PubMed1996

Endogenous interleukin 6 levels in patients with metastatic malignant melanoma: correlation with tumor burden.

The involvement of interleukin (IL-) 6 in malignant disease has been investigated in a variety of different malignancies. To evaluate whether serum IL-6 is a useful disease marker in metastatic malignant melanoma (MMM), we studied the time course of endogenous IL-6 secretion in 41 patients treated with cisplatinum, IL-2, and IFN-alpha. Furthermore, the relationship of endogenous IL-6 concentrations to the tumor burden and/or the clinical response was also evaluated. The baseline serum IL-6 levels were significantly higher in patients with MMM than in the control group (P = 0.002). When tumor burden was taken into consideration, we found that IL-6 levels were higher in patients with high tumor burden than in patients with low tumor burden. During treatment in the whole patient population, a higher serum IL-6 level was observed in nonresponding as compared to responding patients at days 7 (P = 0.0005), 21 (P = 0.002), and 35 (P = 0.009). The follow-up of serum IL-6 in patients with MMM according to the tumor burden and clinical response demonstrated that: (a) IL-6 levels were significantly higher at days 7 and 21 in patients with high tumor burden as compared to those with low tumor burden; and (b) IL-6 levels remain significantly higher in nonresponding patients as compared to responding patients regardless of the tumor burden. From these results, we can conclude that endogenous IL-6 may play a role in the failure of IL-2 therapy in such patients, since the very early IL-6 increase is correlated with the tumor mass and nonresponse to biochemotherapy. Therefore, it seems that the early detection of endogenous IL-6 may represent valuable information for monitoring the response to biochemotherapy in patients with MMM.

Adult↗
PubMed1995

Fotemustine, dacarbazine, vindesine combination chemotherapy in advanced malignant melanoma: a phase II study of 43 patients.

Fotemustine and dacarbazine constitute the most active single chemotherapeutic agents in the treatment of melanoma. In this phase II study we evaluated the activity and toxicity of a combination of fotemustine, dacarbazine and vindesine as a means of increasing response rate and survival time. Between September 1989 and November 1993, 43 patients with advanced melanoma were treated with a combination of 100 mg/m2 fotemustine on days 1 and 8, 250 mg/m2 dacarbazine on days 15 and 16 and 2 mg/m2 vindesine on days 15 and 16 as induction treatment. After a 5-week rest period, the patients exhibiting a response or stable disease received the same drugs administered once every 28 days as maintenance therapy until either progression or toxicity was observed. Among 41 evaluable patients, there were six complete responses and eight partial responses. The overall response rate was 32% (95% confidence interval: 18-46%), with 8 months median duration of response. Median survival time was 10 months. This regimen was well tolerated. From this large phase II study, we conclude that such a combination is active against advanced malignant melanoma and seems to be more effective than fotemustine or dacarbazine used alone, especially on visceral metastatic sites.

Adult↗
PubMed1995

A role for mesenchyme-derived tachykinins in tooth and mammary gland morphogenesis.

Tachykinin peptides such as substance P (SP) function as neurotransmitters and neuromodulators in the mammalian central and peripheral nervous systems. Here, we provide evidence that they may also play an important role in the morphogenesis of some nonneural organs where epithelial-mesenchymal interactions are involved. We show the following. (1) mRNA encoding tachykinin precursor proteins is expressed transiently in condensing mesenchyme during the development of mouse tooth germ, mammary gland, limb bud, external auditory meatus and genital tubercle. (2) In developing tooth germ and mammary gland; mRNA encoding the neutral endopeptidase (NEP) that degrades secreted tachykinins is spatially and temporally co-expressed with tachykinin precursor mRNA. (3) SP and the mRNA encoding SP receptors are also expressed in the developing tooth germ. (4) Tooth development in explant cultures is blocked both by tachykinin-precursor-specific antisense oligonucleotide and by an SP receptor antagonist: in both cases the block is relieved by exogenous SP. Together, these findings suggest a surprising new role for tachykinins in tooth and mammary gland morphogenesis, and possibly also in limb, ear and external genitalia morphogenesis.

Animals↗
PubMed1994

A 17-kDa Nicotiana tabacum cell-wall peptide acts as an in-vitro inhibitor of the cell-wall isoform of acid invertase.

When cell-wall invertase (CWI) from Nicotiana tabacum L. cell-suspension cultures, either non-transformed or transformed with Agrobacterium tumefaciens, was salt-eluted from intact cells and purified on Sulfopropyl-Sephadex (SPS) by pH-gradient elution, the enzyme lost about 50% of its activity during a 1-h incubation at pH 4.8. However, Western-blot analysis indicated no appreciable enzyme degradation. Re-chromatography of CWI peak fractions on SPS using NaCl-gradient elution showed the presence of a 17-kDa peptide (p17) in fractions with low CWI activity but strong CWI immunosignal (Weil and Rausch 1994, Planta 193, 430-437). When separating CWI from p17 by Concanavalin A (Con A)-Sepharose chromatography, inhibition could be restored by incubating the inhibitor-containing fraction with inhibitor-free CWI. More than 90% of CWI could be inhibited, suggesting that all CWI was susceptible to p17 binding. The presence of divalent metal ions (Ca2+, Mg2+, Zn2+) during pre-incubation of CWI with p17 reduced CWI inhibition substantially. Also, sucrose protected CWI against inhibition by p17 (half-maximum protection at 1.3 mM). Binding of p17 to CWI during a 1-h pre-incubation was pH-dependent, pH 4.5 causing maximum inhibition, whereas at pH 6.5 no inhibition was observed. Gel-permeation chromatography revealed that the native inhibitor acts as a monomer. Immunoprecipitation of CWI co-precipitated p17, confirming direct binding of p17 to CWI. When fractions containing CWI and p17 were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and subsequent Western blotting a diffuse immunosignal of 86-90 kDa was observed (in addition to the prominent CWI signal at 69 kDa).(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1994

Study of IL-2 receptor expression after chemoimmunotherapy in patients treated for metastatic malignant melanoma.

Using flow cytometry, cellular IL-2 receptors were studied before and following chemoimmunotherapy combination in 20 patients with metastatic malignant melanoma (MMM). Patients received cisplatin (100 mg/m2) at days 1 and 28, recombinant IL-2 by continuous infusion from days 3 to 6, 17 to 21, 31 to 34, and 45 to 49. Interferon-alpha (IFN-alpha) was given subcutaneously three times weekly. In terms of clinical response, we observed 55% objective response (complete: 15%). When pretreatment blood samples were compared with those of healthy donors, we did not observe any change in low (alpha chain) and high affinity receptor (alpha + beta) expression. In contrast, intermediate affinity p75 (beta chain) expression was decreased significantly (P < or = 0.0001) in MMM patients. During treatment, we found a dramatic increase of beta chain as well as high affinity (alpha + beta) expression in responding patients, as soon as IL-2 therapy began. Furthermore, the increase of beta chain expression was limited to natural killer (NK) cells (CD56+). In non-responding patients, on the other hand, increase of both receptors was seen only at day 31. These data suggest the involvement of beta chain expression in the mechanism of cell activation after chemoimmunotherapy. Moreover, this early beta chain expression is correlated with the clinical response to chemoimmunotherapy.

Adult↗
PubMed1994

Follow up of soluble IL-2 receptor level in metastatic malignant melanoma patients treated by chemoimmunotherapy.

Immunological parameters following chemoimmunotherapy combination were studied in 31 patients with metastatic malignant melanoma. They received Cisplatin (100 mg/m2) on day 1 and 28, recombinant IL-2 (rIL-2; Eurocetus) in continuous infusion from day 3 to 6, 17 to 21, 31 to 34 and 45 to 49. Interferon-alpha (IFN-alpha; Roche) was given subcutaneously three times weekly. No significant change in CD4/CD8 ratio at onset or during treatment was observed between responder (n = 19) and non-responder (n = 12) patients. Regarding the IL-2 receptor (IL-2R) study, the percentage of cells expressing Tac (p55) receptor did not change either for healthy volunteers (n = 20) and patients before any therapy, or between responder and non-responder patients. Concerning serum soluble IL-2R shedding before therapy, we observed a significant increase (P = 0.001) in patients (79 +/- 40 pM) compared with healthy donors (30 +/- 15 pM), but no significant variation was seen between responder and non-responder patients. In contrast, during the treatment, the soluble IL-2R level increased in both groups but, interestingly, a significant difference was found between responder and non-responder patients from day 7 (P < 0.05) to day 21 (P < or = 0.01), suggesting that the cells from non-responder may be slower in becoming stimulated. This finding is the most striking point of our study and suggests that sIL-2R might be an early predictive factor of the clinical response as obtained by logistic regression (P = 0.0063). Therefore patients with a serum soluble IL-2R level greater than 250 pM at day 21 have a 12-fold more chance of undergoing a clinical response.

Adult↗
PubMed1993

Biologic response to anti-CD16 monoclonal antibody therapy in a human immunodeficiency virus-related immune thrombocytopenic purpura patient.

A patient with refractory human immunodeficiency virus (HIV)-related immune thrombocytopenic purpura (ITP) was treated with 3G8 (anti-CD16) monoclonal antibody on days 1, 3, and 8 (25, 25, and 50 mg were administered intravenously, respectively). Side effects were those expected after the administration of a xenogenic protein, but a severe bone pain occurred from the second injection. At the time of the initiation of the treatment the platelet count was 20,000/mm3 and the absolute CD4 number was 100/mm3. We obtained a long-term correction of thrombocytopenia and, to a lesser extent, there was a stabilization of CD4 lymphocytes for 18 months. We observed a significant stimulation of natural killer (NK) function and an elevation in the serum level of tumor necrosis factor alpha, interferon gamma, and granulocyte-macrophage colony-stimulating factor. This suggests that in HIV-related ITP the removal of platelets is mediated by low-affinity Fc gamma receptors (CD16). The stimulation of NK function and elevation in CD4+ lymphocytes may be related to the production of cytokines by activated human NK cells through the interaction of their CD16-bearing receptor with the 3G8 monoclonal antibody. This observation warrants confirmation and further clinical trials.

Acquired Immunodeficiency Syndrome↗
PubMed1992

[Treatment of primary cancer of the breast in elderly women. Role of hormone therapy].

About 40 percent of newly diagnosed breast cancers occur in women older than 65. Hormonotherapy plays an important role as adjuvant treatment of primary cancers in post-menopausal women because of their great hormone-dependence. The drug of choice is tamoxifen which is very well tolerated. Its beneficial effect appears to be related to the duration of administration. It also seems to be particularly promising in the initial treatment (neoadjuvant) of elderly women and potentially beneficial in the breast cancers said to be of good prognosis when the axillary nodes are not involved.

Aged↗
PubMed1992

Phase I study of Datelliptium chloride, hydrochloride given by 24-h continuous intravenous infusion.

Datelliptium chloride, hydrochloride (SR 95 156B, NSC 626718X, DHE) was studied in a phase I trial of escalating doses given on a single 24-h continuous intravenous infusion schedule. Doses were escalated from 40 to 500 mg/m2 in 19 patients who received a total of 24 courses. Courses were repeated after a minimal interval of 3 weeks. Local venous toxicity occurred at low doses (less than or equal to 100 mg/m2) and was circumvented by the use of a central venous access for higher doses. Other clinical adverse events occurred (greater than or equal to 330 mg/m2), including moderate nausea and vomiting, mild diarrhea, dry mouth, neuropsychiatric manifestations, and fatigue. All of these side effects were reversible and none was dose-limiting. The dose-limiting toxicity was related to hepatic laboratory-test abnormalities in the form of reversible elevations of levels of serum bilirubin and liver enzymes at doses of greater than or equal to 330 mg/m2. The maximum tolerated dose for this schedule is 500 mg/m2. Hematologic toxicity was minimal and non-dose-limiting. Neither drug-related deaths nor objective complete or partial responses were observed. However, a minor response and a long-term disease stabilization were obtained.

Adult↗
PubMed1992

Antibodies raised against peptide fragments of CD16 reacting with membrane and soluble form of CD16. I: Production and characterization.

Monoclonal antibodies (MAbs) were generated against human CD16 (Fc gamma RIII) by fusion of NS1 myeloma cells with spleen cells from BALB/c mice immunized with synthetic peptide sequences derived from the CD16 genes. After screening, four hybridomas secreting MAbs (2 IgM and 2 IgG) were selected, cloned and characterized for their activity against CD16 by ELISA test, flow cytometry, rosette inhibition and immuno-blotting. MAbs reacted strongly in ELISA with a soluble form of CD16 (sCD16) present in human serum and to a lesser degree with soluble recombinant CD16 (srCD16). The binding characteristics of the four antibodies to the sCD16 were different, implying that the antibodies recognize different CD16 epitopes. FACS analysis of peripheral blood from healthy volunteers demonstrated that these MAbs are highly reactive with membrane CD16 of neutrophils cells (70-95%) and with a subset of lymphocytes (6-14%). These MAbs seem interesting and may lead to the purification of the soluble human CD16 and to the knowledge of its functions, its physiological role and the cellular polymorphism.

Amino Acid Sequence↗
PubMed1992

Identification of schistosome-infected snails by detecting schistosomal antigens and DNA sequences.

Cercarial shedding tests do not provide species identification of the schistosomes concerned and cannot detect prepatent schistosomal infections. We have demonstrated that both immunodetection by ELISA of schistosomal antigens in snail hemolymph, and dot hybridization of snail extracts by a DNA probe representing highly repeated sequences, proved suitable for detecting infected snails during prepatency as well as patency. A group-specific monoclonal antibody was found to be suitable for detecting Schistosoma mansoni infection in Biomphalaria sp., but not for positive identification of S. haematobium in Bulinus sp. Comparative evaluation of the diagnostic qualities, and technical aspects and cost of these tests, point to the superiority of the immunodetection approach for large scale detection of snails prepatently infected with S. mansoni. This approach is potentially useful for providing extended information on schistosome-snail epidemiology that may facilitate rapid evaluation of the danger of post-control reinfection, and help make decisions on the time and place of supplementary control measures. In this context the potential usefulness of the immunodetection or DNA probing approach for facilitating catalytic model representation of schistosome-snail epidemiology warrants further evaluation. Specific identification of S. haematobium in Bulinus by either of these approaches may be possible depending on the development of suitable antibodies or DNA probes.

Animals↗
PubMed1992

Attempted prevention of blast crisis in chronic myeloid leukemia by the use of pulsed doses of cytarabine and lomustine. A Cancer and Leukemia Group B study.

An attempt to prevent the blast crisis in chronic myeloid leukemia by the use of pulsed doses of (cytarabine cytosine arabinoside) and lomustine was attempted as a cooperative group study by Cancer and Leukemia Group B. The basis for this study was to delay the development of blast crisis by pulsing dose of drugs known to be effective against emerging "blast" cells. The experimental arm which consisted of cytarabine and lomustine did not produce overall results superior to conventional treatment with busulfan. This was related to the non-hematologic effects of the combination which produced significant gastrointestinal toxicity leading to relatively early discontinuation of the combination. Nevertheless, the trial design allowed relatively prompt discontinuation of experimental arm and cross-over to conventional treatment with either hydrea or busulfan. No evidence existed that the use of new drug combinations in CML prejudiced the patient's chance to response to conventional chemotherapy. Thus, a role model for future trials in this disease was developed. With the development of the interferons and other experimental forms of therapy this conceptual development may be of significance.

Antineoplastic Combined Chemotherapy Protocols↗