Biomedical subjects

John A Glaspy

Publications and source records attributed to John A Glaspy.

At least 19 recordsLinked to original sources

PubMed2006

Effect of altering dietary omega-6/omega-3 fatty acid ratios on prostate cancer membrane composition, cyclooxygenase-2, and prostaglandin E2.

PURPOSE: To determine whether altering the dietary content of omega-6 (n-6) and omega-3 (n-3) polyunsaturated fatty acids affects the growth of androgen-sensitive prostate cancer xenografts, tumor membrane fatty acid composition, and tumor cyclooxygenase-2 and prostaglandin E(2) (PGE(2)) levels. EXPERIMENTAL DESIGN: Individually caged male severe combined immunodeficiency mice were fed isocaloric 20% kcal fat diets with the fat derived either primarily from n-6 fatty acids (n-6 group) or with the fat consisting of n-6 and n-3 fatty acids in a ratio of 1:1 (n-3 group), and injected s.c. with Los Angeles Prostate Cancer 4 (LAPC-4) cells. Tumor volumes and mouse weights were measured weekly, caloric intake was measured 3 days per week, and tumors and serum were harvested at 8 weeks postinjection. RESULTS: Tumor growth rates, final tumor volumes, and serum prostate-specific antigen levels were reduced in the n-3 group relative to the n-6 group. The n-3 group tumors had decreased proliferation (Ki67 staining) and increased apoptosis (terminal nucleotidyl transferase-mediated nick end labeling staining). In vitro proliferation of LAPC-4 cells in medium containing n-3 group serum was reduced by 22% relative to LAPC-4 cells cultured in medium containing serum from the n-6 group. The n-6/n-3 fatty acid ratios in serum and tumor membranes were lower in the n-3 group relative to the n-6 group. In addition, n-3 group tumors had decreased cyclooxygenase-2 protein and mRNA levels, an 83% reduction in PGE(2) levels, and decreased vascular endothelial growth factor expression. CONCLUSION: These results provide a sound basis for clinical trials evaluating the effect of dietary n-3 fatty acids from fish oil on tumor PGE(2) and membrane fatty acid composition, and serum and tumor biomarkers of progression in men with prostate cancer.

Administration, Oral↗

PubMed2006

A phase I/II trial testing immunization of hepatocellular carcinoma patients with dendritic cells pulsed with four alpha-fetoprotein peptides.

Alpha-fetoprotein (AFP) is a self protein expressed by fetal liver at high levels, but is transcriptionally repressed at birth. AFP is up-regulated in hepatocellular carcinomas, and patients with active disease could have plasma levels as high as 1 mg/mL. We previously identified four immunodominant HLA-A*0201-restricted peptides [hAFP(137-145) (PLFQVPEPV), hAFP(158-166) (FMNKFIYEI), hAFP(325-334) (GLSPNLNRFL), and hAFP(542-550) (GVALQTMKQ)] derived from human AFP that could stimulate specific T cell responses in healthy donor peripheral blood lymphocytes in vitro. We conducted a phase I/II clinical trial in which HLA-A*0201 patients with AFP-positive hepatocellular carcinoma were immunized with three biweekly intradermal vaccinations of the four AFP peptides pulsed onto autologous dendritic cells (DC). DCs were prepared from adherent peripheral blood mononuclear cells cultured with granulocyte-macrophage colony-stimulating factor and interleukin-4 for 7 days. Sixteen subjects were enrolled and 10 were treated. Peripheral blood lymphocytes were isolated from these patients before, during, and after AFP peptide/DC immunization and were tested ex vivo with MHC tetramer and IFNgamma ELISPOT analysis. Six of 10 subjects expanded statistically significant levels of AFP-specific T cells postvaccine to at least one peptide by MHC tetramer. Also, 6 of 10 subjects increased IFNgamma producing AFP-specific T cell responses to at least one of the peptides postvaccination, by ELISPOT. We conclude that the human T cell repertoire is capable of responding to the AFP self antigen after the administration of AFP peptide-pulsed DC even in an environment of high circulating levels of this oncofetal antigen.

Adult↗

PubMed2006

Immunosensitization of tumor cells to dendritic cell-activated immune responses with the proteasome inhibitor bortezomib (PS-341, Velcade).

Proteasome inhibition results in proapoptotic changes in cancer cells, which may make them more sensitive to immune effector cells. We established a murine model to test whether the proteasome inhibitor bortezomib could sensitize established B16 melanoma tumors to dendritic cell (DC)-activated immune effector cells. Day 3-established s.c. B16 tumors had significantly decreased tumor outgrowth when treated with a combination of bortezomib and DC, regardless of whether the DC were loaded or not with a tumor Ag. In vivo Ab-depletion studies demonstrated that the effector cells were NK and CD8+ cells, but not CD4+ cells. NF-kappaB nuclear transcription factor assay and gene-expression profiling of B16 treated with bortezomib was consistent with inhibition of NF-kappaB target genes leading to a proapoptotic phenotype. In vitro lytic assays demonstrated that TNF-alpha, but not perforin, Fas-ligand, or TRAIL, was responsible for bortezomib-sensitized B16 cytotoxicity. In conclusion, the proteasome inhibitor bortezomib can pharmacologically sensitize tumor cells to the lytic effects of DC-activated immune effector cells.

Animals↗

PubMed2006

Definition of an immunologic response using the major histocompatibility complex tetramer and enzyme-linked immunospot assays.

PURPOSE: Define an immunologic response using the tetramer and enzyme-linked immunospot (ELISPOT) assays. EXPERIMENTAL DESIGN: Ten healthy subjects and 21 patients with melanoma (all HLA-A*0201) donated a total of 121 blood samples to determine the lower limit of detection (LLD), analytic coefficient of variation (aCV), and physiologic CV (pCV) of the tetramer and ELISPOT assays. The mean, SD, and reference change value (RCV) were calculated to define changes beyond the assay imprecision, and its application was tested in the monitoring of T-cell expansion after CTLA4 blockade with ticilimumab (CP-675,206). RESULTS: The LLD for the tetramer assay was 0.038% CD8+ cells and seven spots per 10(5) peripheral blood mononuclear cells for the ELISPOT assay. The aCV of the tetramer assay was <10% and was higher for the ELISPOT (24.69-36.32%). There was marked between-subject variability on baseline homeostatic values, which was correlated to prior antigen exposure. An immunologic response was defined as an increase beyond the mean + 3 SD in antigen-specific cells for subjects with baseline levels below the LLD, or beyond the assay RCV for baseline levels above the LLD. In four patients receiving ticilimumab, expansions of antigen-specific T cells beyond the assay variability were noted for EBV and MART1 antigens. CONCLUSIONS: A combined approach of change from negative (below the LLD) to positive (above the LLD) and a percentage change beyond the assay variability using the RCV score can be computed to define which change in circulating antigen-specific T cells represents a response to immunotherapy.

Adult↗

PubMed2005

Antitumor activity in melanoma and anti-self responses in a phase I trial with the anti-cytotoxic T lymphocyte-associated antigen 4 monoclonal antibody CP-675,206.

PURPOSE: Cytotoxic T lymphocyte-associated antigen 4 (CTLA4) blockade with CP-675,206, a fully human anti-CTLA4 monoclonal antibody, may break peripheral immunologic tolerance leading to effective immune responses to cancer in humans. A phase I trial was conducted to test the safety of CP-675,206. PATIENTS AND METHODS: Thirty-nine patients with solid malignancies (melanoma, n = 34; renal cell, n = 4; colon, n = 1) received an intravenous (IV) infusion of CP-675,206 at seven dose levels. The primary objective was to determine the maximum-tolerated dose and the recommended phase II dose. RESULTS: Dose-limiting toxicities and autoimmune phenomena included diarrhea, dermatitis, vitiligo, panhypopituitarism and hyperthyroidism. Two patients experienced complete responses (maintained for 34+ and 25+ months), and there were two partial responses (26+ and 25+ months) among 29 patients with measurable melanoma. There have been no relapses thus far after objective response to therapy. Four other patients had stable disease at end of study evaluation (16, 7, 7, and 4 months). Additionally, five patients had extended periods without disease progression (36+, 35+, 26+, 24+, and 23+ months) after local treatment of progressive metastases. Longer systemic exposure to CP-675,206 achieved in higher dose cohorts predicted for a higher probability of response. CONCLUSION: CP-675,206 can be administered safely to humans as a single IV dose up to 15 mg/kg, resulting in breaking of peripheral immune tolerance to self-tissues and antitumor activity in melanoma.

Adult↗

PubMed2005

Broad antitumor protection by dendritic cells administered to CD8alpha knock out mice.

Dendritic cell (DC) administration to CD8alpha knock-out (CD8alphaKO) mice results in a strong antigen-non-specific protection to a B16 murine melanoma tumor challenge. This response is mediated by lytic NK cells and cytokine-producing CD4 cells. We aimed to determine the signals that guide tumor targeting of this response. CD8alphaKO mice in the C57BL/6 background received subcutaneous (s.c.) injections of immature DC. Mice were challenged in vivo or assayed for lytic activity in vitro to a panel of syngeneic tumors with different levels of MHC class I expression. These studies support the following conclusions: (1) DC administration to CD8alphaKO mice results in protective in vivo responses to syngeneic tumors from epithelial, neuroectodermal and hematopoietic origin; in vivo protection is independent of the level of MHC classes I and II expression. (2) The in vitro lytic activity of DC-activated NK cells from CD8alphaKO mice has sensitive and insensitive targets, which is independent of the cell lineage or the level of inhibitory self-MHC surface molecules. (3) In sensitive targets a putative activating NK ligand in DC-stimulated NK cells from CD8alphaKO mice signals directly to PI3-K, but is distinct from NKG2D.

Animals↗

PubMed2005

Natural killer cells play a critical role in the immune response following immunization with melanoma-antigen-engineered dendritic cells.

Tumor antigen gene-modified dendritic cells (DC) generates robust antigen-specific protective antitumor responses. Though the role of CD4 positive and CD8 positive cells in the immunological response to gene-modified DC has been well-characterized, the role of NK cells in this response has been somewhat less clear. Owing to the significant contribution of innate immunity in other model systems, we postulated that NK cells would hold a critical position in the generation of an immune response following immunization with tumor antigen-engineered DC. Immunization with MART-1 melanoma antigen-engineered DC in C57BL/6 mice resulted in the generation of antigen-specific cytotoxic T lymphocytes and in vivo protective responses to the murine B16 melanoma. These responses were dependent on the presence of functional NK cells, although NK cells alone were not sufficient in generating protective responses. Adoptive transfer of NK cells into an NK-deficient but T-cell-competent environment restored the protective response to gene-modified DC immunization. In conclusion, protective immunity after tumor antigen gene-modified DC immunization requires collaboration between CD4+ and CD8+ T cells and NK cells.

Adoptive Transfer↗

PubMed2005

Novel interactions of vitamin E and estrogen in breast cancer.

The prevention of breast cancer through dietary modification is an active area of clinical and epidemiological research. It has been proposed that dietary supplementation of vitamin E may reduce a woman's risk of developing breast cancer. However, the exact mechanism remains unknown. alpha-Tocopherol is the most biologically active form of vitamin E. We investigated the effect of vitamin E (alpha-tocopherol) on breast cancer cell growth. A dose-dependent inhibition of cell proliferation was found in estrogen receptor (ER)-positive cells showing a potent suppression of growth at 100 microM vitamin E in MCF-7 (53%) and T47D (75%) cells. Vitamin E reduced significantly the response of both cell lines to estrogen (10 nM), and cell proliferation was decreased in MCF-7 and T47D cells by 69% and 84%, respectively. No growth inhibition was observed when cells were grown in the absence of estrogen. Vitamin E altered and decreased the growth inhibition induced by tamoxifen (10 microM) in MCF-7 (33%) and T47D (54%) cells. In addition, the immunostaining of ER of MCF-7 cells was reduced by 30% in the presence of vitamin E, suggesting an effect of vitamin E on the expression of ER. This provides evidence that vitamin E may inhibit ER-positive cell growth by altering the cellular response to estrogen.

Antineoplastic Agents, Hormonal↗

PubMed2005

The development of erythropoietic agents in oncology.

The erythropoietic agents have achieved a remarkable degree of success as products for the treatment of anaemia associated with cancer chemotherapy. Three agents, epoetin-alpha, epoetin-beta and darbepoetin-alpha, share this global market and have demonstrated similar efficacy and share similar shortcomings, primarily a lower magnitude of cost/benefit than is the case for the dialysis patient. The continued success of these agents will depend on their ability to address the issue of resistance to therapy in the cancer setting, with the most promising and practical initiatives including cotherapy with parenteral iron, and earlier initiation of therapy. Recently, safety issues have arisen with respect to these agents in the cancer setting, particularly focused on possible promotion of tumour progression. A large body of data suggests that these agents are safe when used in accordance with the package inserts. The data bearing upon these issues will be reviewed and three new agents entering clinical development will be described.

Animals↗

PubMed2005

Cancer patient survival and erythropoietin.

Cancer patients are frequently anemic. Treatment of anemic patients with erythropoiesis-stimulating proteins (ESPs) such as epoetin and darbepoetin is associated with benefits that include a reduced transfusion risk and improved quality of life. The recent reports of two randomized trials in which ESP treatment was associated with a decreased survival raised valid concerns regarding the safety of these agents in oncology practice. Reports of erythropoietin receptors on non-hematologic human tumor cells have increased the level of concern and provided a relatively simple model for the effects of ESPs on tumor progression and resistance to treatment. This article reviews available data, which lead to a number of conclusions: 1) the two trials suggesting a negative impact on survival have serious methodologic issues that may compromise interpretation; 2) when used to treat rather than prevent anemia in cancer patients, ESPs show no significant negative impact on survival outcomes; 3) with the exception of erythroleukemia cell lines, the presence of functional erythropoietin receptors on human tumor cells has not been conclusively shown; and 4) a sound theoretical basis exists, supported by preclinical evidence, that any effect of ESP therapy on tumor outcomes may depend on baseline hemoglobin levels, with different effects when anemic and non-anemic individuals are treated. For the present, it is prudent to withhold ESP therapy unless hemoglobin concentrations fall below 12 g/dL and to titrate treatment to maintain a target of 12 g/dL, with adjustments in therapy to insure that levels do not exceed 13 g/dL.

Anemia↗

PubMed2004

Enhanced tumor responses to dendritic cells in the absence of CD8-positive cells.

Wild-type mice immunized with MART-1 melanoma Ag-engineered dendritic cells (DC) generate strong Ag-specific immunity that has an absolute requirement for both CD8(+) and CD4(+) T cells. DC administration to CD8 alpha knockout mice displayed unexpectedly enhanced levels of protection to tumor challenge despite this deficiency in CD8(+) T cells and the inability to mount MHC class I-restricted immune responses. This model has the following features: 1) antitumor protection is Ag independent; 2) had an absolute requirement for CD4(+) and NK1.1(+) cells; 3) CD4(+) splenocytes are responsible for cytokine production; 4) lytic cells in microcytotoxicity assays express NK, but lack T cell markers (NK1.1(+) alpha beta TCR(-) CD3(-)); and 5) the lytic phenotype can be transferred to naive CD8 alpha knockout mice by NK1.1(+) splenocytes. Elucidation of the signaling events that activate these effective cytotoxic cells and the putative suppressive mechanisms in a wild-type environment may provide means to enhance the clinical activity of DC-based approaches.

Adenoviruses, Human↗

PubMed2004

Surveillance of the eye and vision in a clinical trial of MART1-transformed dendritic cells for metastatic melanoma.

PURPOSE: To report the protocol for surveillance of the eye and vision in a clinical trial of MART1-transduced dendritic cells for metastatic melanoma. METHODS: In a phase I/II clinical trial of dendritic cell-based genetic immunotherapy for metastatic cutaneous melanoma, ophthalmic evaluation is performed prior to immunization (Baseline Evaluation), 56+/-7 days after first vaccination (mid-study evaluation), when dendritic cell injections are complete 112+/-7 days after first vaccination (end-study evaluation) and 168+/-7 days after first vaccination (post-study evaluation). RESULTS: The protocol for baseline, mid-study and end-study evaluations of the eye and vision includes ophthalmic history, comprehensive ophthalmic examination, psychophysical and electrophysiological visual function assessment, fundus photography and fluorescein angiography. Post-study evaluation consists of the 25-item visual functioning questionnaire augmented to elicit autoimmune manifestation with complete ophthalmic evaluation if vision-related symptoms or abnormalities are noted during or after the vaccination. CONCLUSION: Limited adverse effects on the eye and vision have been reported in melanoma immunotherapy trials, although this novel mode of therapy has the potential to induce melanoma paraneoplastic syndromes known to severely impair vision. Therefore, surveillance of the eye and vision should be considered in melanoma immunotherapy trials.

Antigens, Neoplasm↗

PubMed2003

T-cell responses to HLA-A*0201 immunodominant peptides derived from alpha-fetoprotein in patients with hepatocellular cancer.

PURPOSE: An existing immunological paradigm is that high concentrations of soluble protein contribute to the maintenance of peripheral tolerance/ignorance to self protein. We tested this hypothesis in a clinical immunotherapy trial using class I-restricted peptide epitopes derived from alpha-fetoprotein (AFP). AFP is a self protein expressed by fetal liver at high levels, but transcriptionally repressed at birth. AFP is de-repressed in a majority of hepatocellular carcinomas (HCCs) and patients with active disease can have plasma levels in the mg/ml range. We previously identified four immunodominant HLA-A*0201-restricted peptides derived from human AFP that could stimulate specific T-cell responses in normal volunteer peripheral blood lymphocytes cultures. We wished to test the hypothesis that AFP peptide-reactive T cells could be expanded in vivo in HCC patients immunized with these four AFP peptides. EXPERIMENTAL DESIGN: We undertook a pilot Phase I clinical trial in which HLA-A*0201 patients with AFP-positive HCC were immunized with three biweekly intradermal vaccinations of the four AFP peptides (100 microg or 500 microg each) emulsified in incomplete Freund's adjuvant. RESULTS: All of the patients (n=6) generated T-cell responses to most or all of the peptides as measured by direct IFNgamma enzyme-linked immunospot (ELISPOT) and MHC class I tetramer assays. CONCLUSIONS: We conclude that the human T-cell repertoire is capable of recognizing AFP in the context of MHC class I even in an environment of high circulating levels of this oncofetal protein.

Adult↗

PubMed2003

Current developments in cancer vaccines and cellular immunotherapy.

This article reviews the immunologic basis of clinical trials that test means of tumor antigen recognition and immune activation, with the goal to provide the clinician with a mechanistic understanding of ongoing cancer vaccine and cellular immunotherapy clinical trials. Multiple novel immunotherapy strategies have reached the stage of testing in clinical trials that were accelerated by recent advances in the characterization of tumor antigens and by a more precise knowledge of the regulation of cell-mediated immune responses. The key steps in the generation of an immune response to cancer cells include loading of tumor antigens onto antigen-presenting cells in vitro or in vivo, presenting antigen in the appropriate immune stimulatory environment, activating cytotoxic lymphocytes, and blocking autoregulatory control mechanisms. This knowledge has opened the door to antigen-specific immunization for cancer using tumor-derived proteins or RNA, or synthetically generated peptide epitopes, RNA, or DNA. The critical step of antigen presentation has been facilitated by the coadministration of powerful immunologic adjuvants, the provision of costimulatory molecules and immune stimulatory cytokines, and the ability to culture dendritic cells. Advances in the understanding of the nature of tumor antigens and their optimal presentation, and in the regulatory mechanisms that govern the immune system, have provided multiple novel immunotherapy intervention strategies that are being tested in clinical trials.

Animals↗

PubMed2003

A randomized, active-control, pilot trial of front-loaded dosing regimens of darbepoetin-alfa for the treatment of patients with anemia during chemotherapy for malignant disease.

BACKGROUND: Anemia in patients receiving chemotherapy can be ameliorated with recombinant human erythropoietin (rHuEPO), which is administered one to three times per week. Darbepoetin alpha, a new erythropoietic agent, has longer serum residence time, allowing it to be administered less frequently. METHODS: Patients (n = 127) were randomized to receive study drug for 12 weeks: either rHuEPO 40,000 U with escalations to 60,000 U for nonresponders or darbepoetin alpha at doses of 4.5 microg/kg per week until hemoglobin concentration >or= 12 g/dL, then 1.5 microg/kg per week (Group 1); 4.5 microg/kg per week for 4 weeks, then 2.25 microg/kg per week for 8 weeks (Group 2); or 4.5 microg/kg per week for 4 weeks, then 3.0 microg/kg every 2 weeks (Group 3). Efficacy was measured using the mean change in hemoglobin level, the proportion of patients achieving a hemoglobin response, the time to response, and the mean change in Functional Assessment of Cancer Therapy-Fatigue Scale scores. Safety was assessed by reports of adverse events. RESULTS: Overall, after 4 weeks of treatment, the mean change (95% confidence interval [95%CI]) in hemoglobin concentration was 0.53 g/dL (95%CI, 0.05-1.02 g/dL), 0.70 g/dL (95%CI, 0.11-1.29 g/dL), and 0.90 g/dL (95%CI, 0.47-1.33 g/dL) in darbepoetin alpha Groups 1, 2, and 3, respectively, and 0.39 g/dL (95%CI, - 0.22-1.00 g/dL) in the rHuEPO group. By the end of the study, the mean change (95%CI) in hemoglobin concentration was 1.35 g/dL (95%CI, 0.67-2.02 g/dL), 1.35 g/dL (95%CI, 0.57-2.12 g/dL), and 1.28 g/dL (95%CI, 0.84-1.73 g/dL) in darbepoetin alpha Groups 1, 2, and 3, respectively, and 1.03 g/dL (95%CI, 0.53-1.53 g/dL) in the rHuEPO group. The early erythropoietic response in patients who were treated with darbepoetin alpha was associated with an early and maintained reduction in patient-reported fatigue. The adverse event profile was comparable with all doses of darbepoetin alpha and rHuEPO. CONCLUSIONS: Darbepoetin alpha, given as a front-loaded dose for 4 weeks and followed by lower and/or less frequent doses, appears to be efficacious and may decrease the time to response relative to treatment with rHuEPO.

Aged↗

PubMed2003

Differential effects of prostaglandin derived from omega-6 and omega-3 polyunsaturated fatty acids on COX-2 expression and IL-6 secretion.

Omega-6 (omega-6) polyunsaturated fatty acids (PUFA), abundant in the Western diet, are precursors for a number of key mediators of inflammation including the 2-series of prostaglandins (PG). PGE(2), a cyclooxygenase (COX) metabolite of arachidonic acid, a omega-6 PUFA, is a potent mediator of inflammation and cell proliferation. Dietary supplements rich in omega-3 PUFA reduce the concentrations of 2-series PG and increase the synthesis of 3-series PG (e.g., PGE(3)), which are believed to be less inflammatory. However, studies on cellular consequences of increases in 3-series PG in comparison to 2-series PG have not been reported. In this study, we compared the effects of PGE(2) and PGE(3) on (i) cell proliferation in NIH 3T3 fibroblasts, (ii) expression and transcriptional regulation of the COX-2 gene in NIH 3T3 fibroblasts, and (iii) the production of an inflammatory cytokine, IL-6, in RAW 264.7 macrophages. PGE(3), unlike PGE(2), is not mitogenic to NIH 3T3 fibroblasts. PGE(2) and PGE(3) both induce COX-2 mRNA via similar signaling mechanisms; however, compared with PGE(2), PGE(3) is significantly less efficient in inducing COX-2 gene expression. Furthermore, although both PGE(2) and PGE(3) induce IL-6 synthesis in RAW 264.7 macrophages, PGE(3) is substantially less efficient compared with PGE(2). We further show that increasing the omega-3 content of membrane phospholipid results in a decrease in mitogen-induced PGE(2) synthesis. Taken together, our data suggest that successful replacement of omega-6 PUFA with omega-3 PUFA in cell membranes can result in a decreased cellular response to mitogenic and inflammatory stimuli.

3T3 Cells↗

PubMed2003

Determinant spreading associated with clinical response in dendritic cell-based immunotherapy for malignant melanoma.

PURPOSE: The purpose of this study was to determine the toxicity and immunological effects of three different doses and two routes of administration of autologous dendritic cells (DCs) pulsed with the MART-1(27-35) immunodominant epitope. EXPERIMENTAL DESIGN: Eighteen HLA-A*0201-positive subjects with stage III-IV melanoma received three biweekly i.v. or intradermal injections of ex vivo generated myeloid DCs pulsed with MART-1(27-35) epitope. Repeated blood samples were processed to obtain peripheral blood mononuclear cells for immunological analysis using IFN-gamma ELISPOT, MHC class I tetramer, intracellular cytokine staining, and microcytotoxicity assays. RESULTS: The frequency of MART-1/Melan-A (MART-1) antigen-specific T cells in peripheral blood increased in all dose levels as assessed by ELISPOT and MHC class I tetramer assays, but without a clear dose-response effect. The intradermal route generated stronger MART-1 immunity compared with the i.v. route. MART-1-specific immunity did not correlate with clinical outcome in any of the four immunological assays used. However, analysis of determinant spreading to other melanoma antigens was noted in the only subject with complete response to this single-epitope immunization. CONCLUSIONS: Intradermal immunization with MART-1 peptide-pulsed DCs results in an increase in circulating IFN-gamma-producing, antigen-specific T cells. The frequency of these cells did not correlate with response. In contrast, spreading of immune reactivity to other melanoma antigens was only evident in a subject with a complete response, suggesting that determinant spreading may be an important factor of clinical response to this form of immunotherapy.

Adult↗

PubMed2003

Hematopoietic management in oncology practice. Part 1. Myeloid growth factors.

Hematopoietic growth factors have transformed the practice of oncology. The two major factors in clinical use are recombinant human (rh) granulocyte colony-stimulating factor (G-CSF, filgrastin [Neupogen]) and granulocyte-macrophage colony-stimulating factor (GM-CSF, sargramostim [Leukine]). These factors differ significantly in their role in hematopoiesis and the regulation of mature effector cell function. G-CSF regulates both basal and neutrophil production and increased production and release of neutrophils from the marrow in response to infection. GM-CSF mediates its effects on the neutrophil lineage through its effects on phagocytic accessory cells and its synergy with G-CSF, but it does not appear to have a role in basal hematopoiesis. Part 1 of this two-part series focuses on the use of the myeloid growth factors rhG-CSF and rhGM-CSF to shorten the duration of chemotherapy-induced neutropenia and thus prevent infection in cancer patients. In randomized trials, rhG-CSF has consistently decreased the duration of neutropenia during all cycles of chemotherapy and reduced the risk of infection by 50% or more. Trials of rhGM-CSF have not reported consistent results.

Antineoplastic Combined Chemotherapy Protocols↗