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J L Murray

Publications and source records attributed to J L Murray.

At least 37 records · Page 2Linked to original sources

Monoclonal antibody treatment of solid tumors: a coming of age.

Over the past 5 years there has been a renewed interest in the use of monoclonal antibodies and immunoconjugates in the treatment of nonhematologic malignancies. This enthusiasm has stemmed from advances in recombinant technology allowing for the production of chimeric and humanized antibodies, from Food and Drug Administration approval of radioimmunoconjugates for use in diagnosis and staging in colorectal, ovarian, and prostate cancer, from studies demonstrating durable response rates in lymphoma and breast cancer, and from trials demonstrating marked efficacy of radiolabeled antibodies in the treatment of non-Hodgkin's lymphoma. Part of the success of chimeric and humanized antibodies in treating solid tumors relates to the lack of human antimouse antibody formation along with enhanced immunogenic effector mechanisms. The pitfalls underlying early trials of murine monoclonal antibodies in solid tumors and newer antibody approaches using unique antigen targets, bifunctional constructs, and alternative routes of antibody administration will be discussed.

Animals↗

Clinical trials of HER-2/neu-specific vaccines.

Recently there has been a renewed interest in developing vaccines for use in cancer treatment. Part of this interest stems from a better understanding of the immune system, the identification of a number of T-cell-specific tumor antigens, more effective adjuvants, and the ability to construct more immunogenic molecules using recombinant DNA techniques. Studies from several laboratories have shown that breast cancer patients have preexisting immunity to the HER-2/neu oncoprotein receptor (HER-2) in the form of elevated antibody titers and T-cell immunity. Preclinical studies showed enhanced delayed-type hypersensitivity and cytotoxic T-lymphocyte precursors in spleens from animals immunized with several human leukocyte antigen class I and class II peptides derived from the HER-2 protein. Phase I trials of these peptides combined with the cytokine granulocyte-macrophage colony-stimulating factor as a part of therapy in patients with HER-2-positive cancers have shown minimal local toxicity, along with enhanced helper T-cell activity and antibody production in patients with minimal disease. Increases in cytotoxic T-lymphocyte precursor activity were less frequent, but in some cases could be enhanced when patient lymphocytes were incubated ex vivo with the proinflammatory cytokine interleukin-12. Other preclinical studies designed to enhance HER-2 peptide immunogenicity are in progress. Additional current and future clinical trials using HER-2-derived vaccines will be discussed.

Animals↗

Phase II study of vinorelbine administered by 96-hour infusion in patients with advanced breast carcinoma.

BACKGROUND: Vinorelbine given by weekly bolus injection is active and less toxic than bolus vinblastine in the treatment of patients with metastatic breast carcinoma. Vinblastine given by 5-day continuous infusion showed a steep dose-response curve. Pharmacokinetic studies of vinorelbine showed that it is possible to achieve a comparable antitumor effect with a smaller amount of the drug if it is given by continuous infusion. The purpose of this study was to determine the efficacy of vinorelbine given by 96-hour continuous infusion to patients with refractory metastatic breast carcinoma patients. METHODS: Between May 1996 and August 1997, 47 patients with metastatic breast carcinoma were registered into the study. All patients previously had received doxorubicin and 70% had undergone prior paclitaxel treatment. Approximately 56% of the patients had >/=2 metastatic sites. All patients received vinorelbine according to the following dose schedule: 8 mg bolus followed by 11 mg/m(2) by continuous infusion over 24 hours every 4 days every 3 weeks. RESULTS: Forty-four patients were evaluable for response. A total of 193 cycles were administered. The overall response rate was 16% (2 patients achieved a complete response and 5 patients achieved a partial response). The median duration of response was 4.3 months and the median overall survival was 8.6 months. Patients with visceral metastases and/or multiple sites of involvement had shorter durations of response than patients with only soft tissue disease or single-site metastasis (3.1 months vs. 4. 9 months) and shorter overall survival (8.1 months vs. 12 months). Dose reductions were necessary due to cumulative stomatitis and/or fatigue in 12 cycles and neutropenia and/or infection in 13 cycles. CONCLUSIONS: Due to toxicity, a revised maximum tolerated dose for continuous infusion vinorelbine is proposed by the authors: 8 mg intravenously over 10 minutes followed by 10 mg/m(2) by continuous infusion over 24 hours every 4 days. The current dose schedule did not offer an advantage either in response rates or survival over the weekly vinorelbine bolus injection in doxorubicin-resistant and paclitaxel-resistant patients.

Adult↗

CCR5 HIV-1 coreceptor activity. Role of cooperativity between residues in N-terminal extracellular and intracellular domains.

Human (H-) CCR5 is the primary coreceptor for ENV-mediated fusion by R5 strains of human immunodeficiency virus type 1, whereas mouse (M-) CCR5 lacks this function. An array of 23 H/M-CCR5 hybrids containing increasing amounts of H-CCR5 extending from the N terminus generated by random chimeragenesis had a biphasic pattern of coreceptor activity with JRFL and 89.6, revealing active regions in the N-terminal extracellular domain (N-ED) and at the junction of cytoplasmic loop 3. The M-CCR5 mutant in which divergent residues were replaced with the corresponding H-CCR5 N-ED sequence (NyYTsE) gained coreceptor function in fusion but not infection experiments. A M-CCR5 double mutant with substitution of human sequences for divergent residues from the N-ED and cytoplasmic loop 3 had augmented coreceptor activity in fusion assays and gain of function in infection experiments. The SIV-251 ENV utilized H- and M-CCR5 and variants. Flow cytometric analysis of M-CCR5 mutants and bifunctional receptors composed of CD4 domains fused to M-CCR5 mutants excluded the possibility that differences in coreceptor activity resulted from variations in cell surface expression. These results demonstrate that the coreceptor activity of the H-CCR5 N-ED is modulated by intracellular residues, illustrating the complexity of CCR5 requirements for interaction with ENV.

Amino Acid Sequence↗

Phase I study of 90Y-labeled B72.3 intraperitoneal administration in patients with ovarian cancer: effect of dose and EDTA coadministration on pharmacokinetics and toxicity.

The tumor-associated glycoprotein 72 (TAG-72) antigen is present on a high percentage of tumor types including ovarian carcinomas. Antibody B72.3 is a murine monoclonal recognizing the surface domain of the TAG-72 antigen and has been widely used in human clinical trials. After our initial encouraging studies (M. G. Rosenblum et al., J. Natl. Cancer Inst., 83: 1629-1636, 1991) of tissue disposition, metabolism, and pharmacokinetics in 9 patients with ovarian cancer, we designed an escalating dose, multi-arm Phase I study of 90Y-labeled B72.3 i.p. administration. In the first arm of the study, patients (3 pts/dose level) received an i.p. infusion of either 2 or 10 mg of B72.3 labeled with either 1, 10, 15, or 25 mCi of 90Y. Pharmacokinetic studies demonstrated that concentrations of 90Y-labeled B72.3 persist in peritoneal fluid with half-lives >24 h after i.p. administration. In addition, 90Y-labeled B72.3 was absorbed rapidly into the plasma with peak levels achieved within 48 h, and levels declined slowly thereafter. Cumulative urinary excretion of the 90Y label was 10-20% of the administered dose which suggests significant whole-body retention of the radiolabel. Biopsy specimens of bone and marrow obtained at 72 h after administration demonstrated significant content of the label in bone (0.015% of the dose/g) with relatively little in marrow (0.005% of the dose/g). The maximal tolerated dose was determined to be 10 mCi because of hematological toxicity and platelet suppression. This typically occurred on the 29th day after administration and was thought to be a consequence of the irradiation of the marrow from the bony deposition of the radiolabel. In an effort to suppress the bone uptake of 90Y, patients were treated with a continuous i.v. infusion of EDTA (25 mg/kg/12 h x 6) infused immediately before i.p. administration of the radiolabeled antibody. Patients (3 pts/dose level) were treated with doses of 10, 15, 20, 25, 30, 35, 40, or 45 mCi of 90Y-labeled B72.3 for a total of 38 patients. EDTA administration resulted in significant myeloprotection, which allowed escalation to the maximal tolerated dose of 40 mCi. Dose-limiting toxicity was thrombocytopenia and neutropenia. Studies of plasma and peritoneal fluid pharmacokinetics demonstrate no changes compared with patients without EDTA pretreatment. Cumulative urinary excretion of the radiolabel was not increased in patients pretreated with EDTA compared with the untreated group. However, analysis of biopsy specimens of bone and marrow demonstrated that bone and marrow content of the 90Y label was 15-fold lower (<0.001% injected dose/g) than a companion group without EDTA. Four responses were noted in patients who received 15-30 mCi of 90Y-labeled B72.3 with response durations of 1-12 months. These results demonstrate the myeloprotective ability of EDTA, which allows safe i.p. administration of higher doses of 90Y-labeled B72.3 and, therefore, clearly warrant an expanded Phase II trial in patients with minimal residual disease after standard chemotherapy or for the palliation of refractory ascites.

Adult↗

Vaccine implications of folate binding protein, a novel cytotoxic T lymphocyte-recognized antigen system in epithelial cancers.

The immune system can be efficiently stimulated and targeted to specific antigens expressed exclusively or preferentially by experimental cancers. The foremost limitations to extending this vaccine technology to the prevalent epithelial-derived cancers are the lack of: (a) identified tumor-associated antigens recognized by cellular immunity; (b) antigens expressed on the majority of tumor cells during disease progression; and (c) immunogenic CTL epitopes. To date, only HER-2/neu has been shown to be the source of naturally occurring, MHC-restricted, CTL-recognized peptides in epithelial tumors. In this study, we demonstrate that the human high-affinity folate binding protein (FBP), which is a source of antigenic peptides recognized in ovarian cancer, is also recognized in breast cancer. Both immunodominant E39 (FBP, 191-199) and subdominant E41 (FBP, 245-253) epitopes are presented by HLA-A2 in these cancers. These peptides are efficient at amplifying the response of tumor-associated lymphocyte populations in terms of lytic function, enhanced proliferation, and specific IFN-gamma release. On a per cell basis, tumor-associated lymphocytes stimulated with the FBP peptides exhibit enhanced cytotoxicity not only against peptide-loaded targets but also against FBP-expressing epithelial tumors of different histologies. Furthermore, FBP peptides induced E39-specific CTLs and E39- and E41-specific IFN-gamma and IP-10 secretion in certain healthy donors. The broad distribution of FBP among >90% of ovarian and endometrial carcinomas, as well as 20-50% of breast, lung, colorectal, and renal cell carcinomas, along with pronounced differential overexpression in malignant tissues compared with the extremely limited expression in normal epithelium, suggests the exciting potential of a widely applicable FBP-based vaccine in epithelial cancers.

Antigen Presentation↗

Ovarian and breast cytotoxic T lymphocytes can recognize peptides from the amino enhancer of split protein of the Notch complex.

In this study we investigated recognition by ovarian tumor associated lymphocyte (OVTAL), and breast tumor associated lymphocytes (BRTAL), of peptides corresponding to the sequence 125-135 of the Aminoenhancer of split (AES) protein. Three of these peptides designated as G75:AES1/2 (128-135), G60: AES1/2 (127-137) and G61: AES1/2 (125-133) correspond to the wildtype AES sequence, while the fourth G76:GPLTPLPV, AES1/2 (128-135) corresponds to a variant sequence of the peptide G75 with the N-terminal Leu substituted to glycine. These sequences were chosen for study because mass-spectrometric analysis (MS) of a CTL active HPLC peptide fraction eluted from immunoaffinity precipitated HLA-A2 molecule, revealed: (a) the presence of an ion with a mass-to-charge ratio (m/z) of 793 which was more abundant than other ions of similar masses; (b) the tentatively reconstituted sequence of the ion 793 matched the sequence of peptide G76. We found that AES peptides G75 (128-135) and G76 (128-135) (L128G) reconstituted CTL recognition at concentrations ranging between 200-500 nM. These concentrations are lower than concentrations reported to activate effector function of CTL recognizing other epithelial tumor Ag. Furthermore, analysis with cloned CD8+ T cells indicated that G75 and G76 were not cross-reactive specificities, suggesting a key role for the N-terminal residues of the variant peptide in dictating specificities. Since the AES proteins are part of a set of transcriptional repressors encoded by the Enhancer of split [E(spl)] genes, and since these repressors are activated to suppress cell differentiation in response to Notch receptors signalling, the AES peptides may represent a novel class of self-antigens that deserve further consideration as tumor Ag in epithelial cancers.

Antigens, Neoplasm↗

Growth and antigen recognition of tumor-infiltrating lymphocytes from human breast cancer.

In the present study, we isolated tumor-infiltrating lymphocytes (TIL) from 21 primary solid tumors and tumor-associated lymphocytes (TAL) from 9 malignant effusions, respectively, of breast cancer patients. Significant proliferation and expansion of T cells was observed in 23 of 30 distinct samples. TIL were isolated from primary tumors by either enzymatic digestion or mechanical disruption. The TIL cultures were initiated using OKT3 mAb in the presence of moderate concentrations (25-50 U/ml) of IL-2, followed by 100 U/ml of tumor necrosis factor (TNF)-alpha. TAL were not stimulated with OKT3 mAb, but all were successfully expanded in culture in the presence of IL-2 alone or together with TNF-alpha. Seven of nine distinct TAL grew in culture as predominantly CD4+ lines. In contrast, only 14 of 21 (66%) of primary breast TIL expanded in culture and were predominantly of CD8+ phenotype. Autologous tumor lysis was observed in seven of eight cases tested. Only one of the four TIL tested and one of the four TAL tested preferentially lysed autologous tumor. HER-2 peptide E75 (369-377) was recognized by two TIL lines of the five primary TIL tested and three of the four TAL tested. This suggests that E75 may be recognized by primary breast tumors. This may be of interest in developing vaccine strategies for therapeutic management of breast cancer.

Antigen-Antibody Reactions↗

Immunologic response to the dual murine anti-Id vaccine Melimmune-1 and Melimmune-2 in patients with high-risk melanoma without evidence of systemic disease.

Melimmune is a dual preparation of two murine anti-idiotypic antibodies (anti-Ids), Melimmune-1 and Melimmune-2, which mimic separate epitopes of the melanoma-associated high molecular weight proteoglycan antigen. In an animal model, vaccination with either anti-Id leads to tumor rejection, and Phase I clinical trials have demonstrated the tolerance of each reagent in humans. We conducted a Phase IB trial of different doses of a one-to-one composition to Melimmune-1 and Melimmune-2 administered with SAF-m adjuvant in patients with resected melanoma without evidence of metastatic disease. A total of 21 patients were enrolled in this multicenter trial. Detailed immune response analysis was conducted on 13 patients enrolled at a single institution. Following vaccination, 12 of the 13 patients demonstrated antibodies to both Melimmune-1 and Melimmune-2, including significant anti-V-region reactivity. Maximum anti-V-region reactivity was generally detected following the last vaccination. Anti-V-region reactivity directed at Melimmune-1 and Melimmune-2 in excess of 1 microgram/ml was detected in 4 and 10 of 12 patients, respectively. Sera from patients obtained at time of peak anti-V-region reactivity did not demonstrate the ability to inhibit Ab1 binding to tumor cells or direct anti-tumor cell reactivity. However, in vitro cellular proliferation was observed in response to Melimmune-1 and/or Melimmune-2 F(Ab')2 in all patients with a mean stimulation index of 12.0 and 27.8, respectively. Overall, the antibody and cellular immune response to Melimmune-2 was more potent than to Melimmune-1, and all antibody doses elicited an immune response. The optimal biologic dose of Melimmune could not be determined in this small patient population.

Adult↗

Proliferative and cytokine responses to class II HER-2/neu-associated peptides in breast cancer patients.

Previous studies have characterized the reactivity of CD8+ CTLs with ovarian and breast cancer. There is little information about the antigens and epitopes recognized by CD4+ T cells in these patients. In this study, we analyzed the ability of T cells from peripheral blood mononuclear cells of breast cancer patients to recognize HER-2/neu (HER-2) peptides. We found that 13 of 18 patients responded by proliferation to at least one of the HER-2 peptides tested. Of these peptides, one designated G89 (HER-2: 777-789) was recognized by T cells from 10 patients. Seven of nine responding patients were HLA-DR4+, suggesting that this peptide is recognized preferentially in association with HLA-DR4. Analysis of the specificity and restriction of the cytokine responses to G89 by G89-stimulated T cells revealed that these cells secreted significantly higher levels of IFN-gamma than interleukin 4 and interleukin 10, suggesting priming for a Th0-T helper 1 response. The same pattern of cytokine responses was observed to the intracellular domain of HER-2 protein, suggesting that G89-stimulated T cells recognized epitopes of the HER-2 protein in association with HLA-DR4. Because HLA-DR4 is present in 25% of humans, characterization of MHC class II-restricted epitopes inducing Th0-T helper 1 responses may provide a basis for the development of multivalent HER-2-based vaccines against breast and ovarian cancer.

Amino Acid Sequence↗

Enhancement of cell-mediated immunity in melanoma patients immunized with murine anti-idiotypic monoclonal antibodies (MELIMMUNE) that mimic the high molecular weight proteoglycan antigen.

The purpose of this study was to determine whether a combination of two anti-idiotypic antibodies that mimic the high molecular weight proteoglycan antigen found on most melanoma tumors was capable of enhancing cellular immunity in vaccinated high-risk patients with melanoma. Twenty-eight stage I-IV high-risk patients with melanoma were immunized with a mixture of variable concentrations of MELIMMUNE-1 and MELIMMUNE-2, along with the adjuvant SAF-m, using two immunization schedules. Peripheral blood mononuclear cells were collected before the first immunization and 4 weeks after the final immunization and tested for in vitro proliferation to MELIMMUNE-1 and MELIMMUNE-2 and for cytotoxicity against 51Cr-labeled target cell lines. Additionally, supernatants from in vitro proliferation cultures were tested for interleukin 10 and IFN-gamma levels. Significant in vitro proliferation to MELIMMUNE-1 and MELIMMUNE-2 were observed in postimmunization samples but not in prevaccination samples. The mean stimulation index for MELIMMUNE-2 (33.7 +/- 0.6) was significantly higher than that for MELIMMUNE-1 (13.9 +/- 0.3; P < 0.025). Supernatants obtained from 78% of the in vitro stimulated cultures pre- or postvaccination contained significant levels of interleukin 10 (range, 0.43-142 pg/ml), whereas IFN-gamma levels were elevated in 53% of postvaccination samples (range, 3-245 pg/ml) but not prevaccination samples. More importantly, we were able to generate specific CTL responses in 43% of the patients, which correlated with elevated IFN-gamma levels. These results indicate that MELIMMUNE enhances cell-mediated immunity in patients with melanoma.

Antibodies, Anti-Idiotypic↗

Identification of naturally processed human ovarian peptides recognized by tumor-associated CD8+ cytotoxic T lymphocytes.

Identification of naturally processed peptides recognized by tumorspecific CTLs may lead to epitope-specific tumor vaccines. Because these epitopes may be expressed differently on epithelial tumors and may differ in their ability to induce CTL in vivo, we have isolated the HLA-A2-peptide complexes by immunoaffinity from an established ovarian tumor line transfected with and expressing HLA-A2 gene. High-performance liquid chromatography-fractionated peptides were used to reconstitute epitopes recognized on HLA-A2 by three HLA-A2+ CD8+ CTL lines. These lines recognized at least three of the same groups of fractions (designated SKOV3.A, -B, and -C) but showed differences in the pattern of recognition of other fractions. To gain insight in the epitope distribution by freshly isolated ovarian tumors, we compared the recognition of peaks SKOV3.B and -C with the corresponding peaks from an ovarian tumor (OVA-6) that expressed similar levels of HLA-A2, using one of these lines (CTL-OVA-5) as indicator. CTL-OVA-5 recognized a large number of epitopes from peaks B and C rechromatographed on more resolving high-performance liquid chromatography gradient. Although a number of peaks appeared to be coincident on both SKOV3 and OVA-6, an even higher number appeared either not to overlap or to overlap only partially. These findings, which represent the first analysis of the epitopes presented by a patient tumor, suggest that the use of tumor line-derived peptides for vaccination may require selection of the epitopes corresponding to the ones presented by freshly isolated human tumors.

Antigens, Neoplasm↗

A Thr552 -->Ile substitution in erythroid band 3 gives rise to the Warrior blood group antigen.

BACKGROUND: Recent family studies established that the low-incidence red cell antigen WARR is not part of the MNS, Lutheran, Lewis, Duffy, Kidd, Xg, Chido/ Rodgers, Kx, or Gerbich blood group systems. Continued serologic and genetic studies of WARR suggest that it is carried on erythroid band 3. STUDY DESIGN AND METHODS: To test the hypothesis that expression of WARR is controlled by the anion exchanger 1 gene (AE1), AE1 intronic primers that flank the exons encoding the membrane domain of band 3 were prepared. Polymerase chain reaction-amplified products corresponding to exons 11-20 of AE1 were analyzed for single-strand conformational polymorphism (SSCP) in DNA from WARR-positive and WARR-negative individuals. RESULTS: An SSCP was detected in exon 14. Subsequent sequencing revealed a C-->T mutation in codon 552 that leads to a Thr-->Ile substitution. Because the C-->T mutation eliminates a Bbs I restriction site, it was possible to confirm the phenotypes of all family members. To study the possible effect of the Thr552-->Ile substitution on the expression and function of band 3, polymerase chain reaction-amplified reverse-transcribed reticulocyte mRNA was digested with Bbs I. Both alleles of band 3 mRNA were detected in similar quantities, which suggests that the substitution underlying WARR did not interfere with mRNA stability. Comparison of sodium dodecyl sulfate-polyacrylamide gel electrophoretic mobility and size patterns revealed no difference between proteins isolated from WARR-positive and WARR-negative red cells. Further, the presence of WARR did not alter the di-isothiocyano-dihydrostilbene disulfonate (DIDS)-inhibitable influx of radiolabeled sulfate. CONCLUSION: Although it appears inconsequential to the function of band 3, the red cell polymorphism known as WARR is controlled by AE1. WARR should be therefore included in the Diego blood group system.

Anion Exchange Protein 1, Erythrocyte↗

Blood group antigens Rb(a), Tr(a), and Wd(a) are located in the third ectoplasmic loop of erythroid band 3.

BACKGROUND: Rb(a), Tr(a), and Wd(a) are three low-incidence blood group antigens that have not been assigned to a particular structure of the red cell membrane. Recent genetic and serologic data suggested erythroid band 3 as a possible carrier of these three antigens. STUDY DESIGN AND METHODS: Ten band 3 gene exons that encode the membrane domain of band 3 were screened for single strand conformation polymorphism (SSCP). Exons displaying SSCP were cloned and sequenced, and the presence of the mutations was verified by restriction digestion. RESULTS: Substitutions 548 Pro-->Leu, 551 Lys-->Asn, and 557 Val-->Met, all located in the third ectoplasmic loop of band 3, were detected in the subjects with Rb(a+), Tr(a+), and Wd(a+) red cells, respectively. The presence of the Rb(a) and Wd(a) mutations was confirmed in additional carriers of these blood group antigens. Chymotryptic cleavage at Tyr 553 and Tyr 555 abolished the agglutinability of Tr(a+) and Wd(a+) cells with the corresponding antisera, further demonstrating that the epitopes are located in the third ectoplasmic loop of band 3. Similar quantities of mRNA corresponding of the two band 3 alleles, a normal pattern of red cell membrane proteins, and normal DIDS (4,4'-diisothiocyanatostilbene-2,2'-disulphonic acid, disodium salt)-inhibitable sulfate flux were detected, which suggests that the mutations do not affect band 3 mRNA stability or band 3 protein expression and transport function. CONCLUSION: Wd(a) and Rb(a), and tentatively Tr(a), can be assigned to the Diego blood group system.

Anion Exchange Protein 1, Erythrocyte↗

Recombinant interleukin-2 in combination with recombinant interferon-gamma in patients with advanced malignancy: a phase 1 study.

Because interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) act synergistically in vitro in the generation of lymphokine-activated killer (LAK) cells. we initiated a clinical trial of these lymphokines in combination. Twenty patients with advanced malignancy were treated at fixed dose levels of recombinant IFN-gamma given by intramuscular (i.m.) injections once a day and recombinant IL-2 given by an intravenous (i.v.) bolus injection 3 times a day for 7 days after a 3-day treatment with fixed doses (250 micrograms/m2/day) of IFN-gamma alone. A minimum of four patients were treated at each of the four dose levels studied. The side effects of the combination therapy were similar to those seen with individual lymphokines and included fever and chills, myalgia, headache, fatigue, nausea. vomiting, peripheral edema, skin rash, and hypotension. The maximum tolerated dose for the combination after a fixed dose of IFN-gamma was 2 x 10(5) U/M2/day (10 micrograms/m2/day) of IFN-gamma and 3 x 10(6) U/M2/day of IL-2, with fluid retention as the dose-limiting toxicity. Whereas natural killer (NK) or LAK activity or both were significantly increased in four of eight patients studied, only one patient with renal cell cancer had a minor response for four treatment cycles. We conclude that combination therapy with cytokines IL-2 and IFN-gamma given in this schedule had manageable toxicity and exhibited immunomodulatory effects in some patients but had no significant antitumor activity in this patient population.

Adult↗

Effect of recombinant alpha-interferon on pharmacokinetics, biodistribution, toxicity, and efficacy of 131I-labeled monoclonal antibody CC49 in breast cancer: a phase II trial.

Preclinical studies have demonstrated that recombinant IFN-alpha (rIFN-alpha) can enhance the tumor associated glycoprotein 72 (TAG-72) on tumors. To determine whether rIFN-alpha could enhance TAG-72 expression in vivo in patients, 15 women with breast cancer were randomized to receive daily injections of rIFN-alpha (3 x 10(6) units/m2 for 14 days) beginning on day 1 (group 1 = 7 patients) or on day 6 (group 2 = 8 patients). On day 3, all patients received a 10-20-mCi tracer dose of 131I-CC49, a high-affinity murine monoclonal antibody reactive against TAG-72, followed by a therapy dose of 60-75 mCi/m2 of 131I-CC49 on day 6. Whole body and single-photon emission computed tomography scans along with whole blood pharmacokinetics were performed following tracer and treatment phases. Hematological toxicity was considerable; reversible grade 3-4 neutropenia and thrombocytopenia was observed in 12 of 15 patients. Twelve of 14 patients tested developed human antimouse antibodies 3-6 weeks after treatment. For group 1 patients, whole blood residence time increased significantly between that predicted from the tracer doses and therapy doses (42.6 +/- 4.7 versus 51.5 +/- 4.8 h, respectively; P < 0.01). The calculated radiation absorbed dose to red marrow from therapy compared to tracer activity was also significantly higher for this group (1.25 +/- 0.35 versus 1. 07 +/- 0.26 cGy/mCi; P < 0.05). Treatment with rIFN-alpha was found to enhance TAG-72 expression in tumors from patients receiving rIFN-alpha (group 1) by 46 +/- 19% (P < 0.05) compared to only 1.3 +/- 0.95% in patients not initially receiving IFN (group 2). The uptake of CC49 in tumors was also significantly increased in rIFN-alpha-treated patients. One partial and two minor tumor responses were seen. In summary, rIFN-alpha treatment altered the pharmacokinetics and tumor uptake of 131I-CC49 in patients at the expense of increased toxicity.

Adult↗

Characterization of 13 novel band 3 gene defects in hereditary spherocytosis with band 3 deficiency.

Hereditary spherocytosis (HS) is a common hemolytic anemia of variable clinical expression. Pathogenesis of HS has been associated with defects of several red cell membrane proteins including erythroid band 3. We have studied erythrocyte membrane proteins in 166 families with autosomal dominant HS. We have detected relative deficiency of band 3 in 38 kindred (23%). Band 3 deficiency was invariably associated with mild autosomal dominant spherocytosis and with the presence of pincered red cells in the peripheral blood smears of unsplenectomized patients. We hypothesized that this phenotype is caused by band 3 gene defects. Therefore, we screened band 3 DNA from these 38 kindred for single strand conformational polymorphisms (SSCP). In addition to five mutations detected previously by SSCP screening of cDNA, we detected 13 new band 3 gene mutations in 14 kindred coinherited with HS. These novel mutations consisted of two distinct subsets. The first subset included seven nonsense and frameshift mutations that were all associated with the absence of the mutant mRNA allele from reticulocyte RNA, implicating decreased production and/or stability of mutant mRNA as the cause of decreased band 3 synthesis. The second group included five substitutions of highly conserved amino acids and one in-frame deletion. These six mutations were associated with the presence of comparable levels of normal and mutant band 3 mRNA. We suggest that these mutations interfere with band 3 biosynthesis leading thus to the decreased accumulation of the mutant band 3 allele in the plasma membrane.

Alleles↗

The inhibition of radiation-induced mutagenesis by the combined effects of selenium and the aminothiol WR-1065.

In order to evaluate the anti-mutagenic effects of the potential chemoprotective compounds selenium and (S)-2-(3-aminopropylamino)ethylphosphorothioic acid (WR-1065), CHO AA8 cells were exposed to both compounds either individually or in combination prior to irradiation. Mutation frequency following exposure to 8 Gy was evaluated by quantitation of the mutations detected at the hprt locus of these cells. Protection against radiation-induced mutation was observed for both 30 nM sodium selenite or 4 mM WR-1065. In addition, the protection against mutation induction provided by the combination of these agents appeared additive. In contrast, sodium selenite did not provide protection against radiation toxicity when provided either alone or in conjunction with WR-1065. In order to evaluate the possible mechanisms of the anti-mutagenic effects observed in these cells, glutathione peroxidase (GPx) activity was evaluated following exposure to the chemopreventative compounds. The addition of sodium selenite to the culture media resulted in a 5-fold increase in GPx activity, which was unaltered by the presence of the WR-1065. Northern analysis of RNA derived from these cells indicated that selenium supplementation resulted in a marginal increase in the mRNA for the cytosolic GPx (GSHPx-1) which was insufficient to account for the stimulation of GPx activity observed in cellular extracts. These results suggest that selenium and WR-1065 offer protection via independent mechanisms and that GPx stimulation remains a possible mechanism of the anti-mutagenic effect of selenium.

Animals↗