Permanent Genetic Resources added to the Molecular Ecology Resources Database 1 February 2010-31 March 2010

This article documents the addition of 228 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Anser cygnoides, Apodemus flavicollis, Athene noctua, Cercis canadensis, Glis glis, Gubernatrix cristata, Haliotis tuberculata, Helianthus maximiliani, Laricobius nigrinus, Laricobius rubidus, Neoheligmonella granjoni, Nephrops norvegicus, Oenanthe javanica, Paramuricea clavata, Pyrrhura orcesi and Samanea saman. These loci were cross-tested on the following species: Apodemus sylvaticus, Laricobius laticollis and Laricobius osakensis (a proposed new species currently being described).

Energetics of Stone-Wales defects in 4 A carbon nanotubes

Density functional calculations have been performed to study the formation of Stone-Wales defects in 4 A single-wall carbon nanotubes, which were firstly synthesized inside the AFI zeolite template. The minimum energy paths from perfect tubes to defect-containing ones are calculated by the nudged elastic band method. It is found that the C--C bonds "along" the tube axis are more likely to be rotated than those bonds "around" the circumference. There is a marked chirality dependence of the formation barriers, which are found to be lower than that of graphite. Our results may raise a question on the origin of superconductivity observed in these 4 A tubes.

Electronic and electrochemical properties of Li-doped carbon nanotube-zeolite complex

The electronic and electrochemical properties of Li-doped carbon nanotube-zeolite complex are studied by first-principles calculations. There are four possible sites for Li to be doped and the reactions are all exothermic. The corresponding energy band structures follow a rigid band picture and there are charge transfers from Li to the nanotube and/or zeolite. The Li capacity of the complex can be reached to 386 mAh g(-1) with only a slight increase in the cell volume, and the complex may be of good cyclic stability during the charge and discharge process. Moreover, a higher voltage of about 4 V can be obtained if the complex is used in an Li-ion battery.

Generation of Janus alginate hydrogel particles with magnetic anisotropy for cell encapsulation

A microfluidic approach for fabrication of Janus hydrogel particles with magnetic anisotropy is demonstrated. Using this technique, cells and magnetic beads (MBs) can be separately embedded in one hydrogel particle to maintain optical performance, and reduce the contact between cells and magnetic beads (nano- or submicron-particles). Alginate cell capsules prepared by this method can be easily controlled and manipulated by external magnetic fields and require no specific surface modification. Bio-degradability and super-paramagnetic properties of these hydrogel particles were also demonstrated experimentally.

Phase I/II study of arginine deiminase (ADI-PEG 20) in patients with advanced malignant melanoma (MM)

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Background: ADI-PEG 20 is an enzyme that degrades arginine, a crucial amino acid central to metabolism and biosynthesis of growth and development of normal and neoplastic cells. Melanoma is auxotrophic for arginine because it lacks argininosuccinate synthetase (ASS), a key enzyme required for synthesis of arginine from citrulline via the urea cycle. This study evaluates the safety and clinical efficacy of ADI-PEG 20 in patients with MM. Methods: Patients with histologically confirmed stage III (unresectable)/ IV cutaneous, uveal or mucosal MM were treated with 40, 80 or 160 IU/m2 ADI-PEG 20 i.m. weekly for 9 weeks in a phase I setting. In a phase II component, 16–25 pts receiving 160 IU/m2 will be evaluated for tumor response (TR) by RECIST. Secondary endpoints for all patients included metabolic response by 18FDG-PET, pharmacodynamics (PD), immunogenicity and ASS tumor expression by immunohistochemistry. Results: As of Nov. 2008, 24 pts were enrolled (40 IU/m2, n=6, 80 IU/m2, n=6, 160 IU/m2, n=12): 14 males, 10 females. Median age: 66 yrs (range 29- 83 yrs). Toxicity consisted primarily of Grade 1/2 adverse events (AE) (injection site pain, myalgia, arthralgia, fatigue, flushing, rash/itch, nausea, diarrhea, hyperuricemia, taste alteration). One dose limiting toxicity (DLT) of G3 arthralgia was observed at 80 IU/m2. Two DLTs (G3 seizure and G3 lymphedema) were reported, at 160 IU/m2. No grade 4 or 5 AEs were observed. Of 22 patients evaluable for TR, 8 had stable disease (SD) with 2 of these durable for ≥ 6 months. Notably, 3 SD were uveal melanoma. 14 patients had progressive disease. PD analysis showed plasma arginine depletion during study weeks 1–6 regardless of dose. Immunohistochemical ASS expression analysis in tumor tissue: negative= 13 pts, < 5% cells positive= 5 pts. Conclusions: ADI-PEG 20 as a single agent is well tolerated in advanced MM leading to consistent arginine depletion. The extent of clinical activity has yet to be shown. Combination therapy of ADI-PEG20 with other treatments such as pro-apoptotic reagents during the first 6 weeks of ADI-PEG 20 treatment while arginine is depleted could lead to synergistic anti-cancer activity.

No significant financial relationships to disclose.

Prognostic significance of leukopenia at the time of diagnosis in acute myeloid leukemia (AML)

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Background: In contrast to the poor prognosis associated with hyperleukocytosis, the prognostic significance of leukopenia at the time of diagnosis of AML is unknown. Methods: Single institution retrospective analysis of 225 consecutive, newly diagnosed AML patients (pts), homogeneously treated between July 1996 and February 2005; and divided into 2 groups based on presenting WBC: < 2,000/uL (30) and > 2,000/uL (195). Simultaneously obtained peripheral blood and marrow blasts were analyzed for cell surface expression of CD34, cKit, CXCR4, PCAM, VLA-2, VLA-3, VLA-4, VLA-5, and FLT3 using flow cytometry. Results: Patients’ characteristics (gender, secondary vs. de novo, and cytogenetic [CTG] risk) were comparable between the 2 groups. Leukopenic AML pts were older (median 56 vs. 53 years, p = 0.02), and had lower induction complete remission [CR] rates: 63% vs. 81% (p = 0.03) by univariate analysis. Induction mortality was 0% for leukopenic and 5% for non-leukopenic pts. In primary refractory pts, median survival was longer for leukopenic (11) vs. non-leukopenic (34) pts: 137 vs. 81 d (p = 0.026). Median follow-up was 22 mos. Event-free (EFS), disease-free (DFS), and overall survivals (OS) were lower in the leukopenic group: 12 vs. 14; 14 vs. 17; and 17 vs. 19 mos, respectively; but did not reach statistical significance. By multivariate analysis, age (p < 0.0001) and CTG risk group (p < 0.0001) were independent predictors of OS, while CTG risk group predicted RFS (p < 0.0001). The level of expression of cell surface adhesion molecules on blood and marrow blasts was comparable for the 2 groups. Conclusions: AML pts presenting with leukopenia have comparable outcomes to those presenting with normal or high WBC despite a lower likelihood of achieving remission. Leukopenic AML did not have over-expression of cell surface adhesion molecules.

No significant financial relationships to disclose.

Regulatory T-cell-mediated attenuation of T-cell responses to the NY-ESO-1 ISCOMATRIX vaccine in patients with advanced malignant melanoma

PURPOSE

NY-ESO-1 is a highly immunogenic antigen expressed in a variety of malignancies, making it an excellent target for cancer vaccination. We recently developed a vaccine consisting of full-length recombinant NY-ESO-1 protein formulated with ISCOMATRIX adjuvant, which generated strong humoral and T-cell-mediated immune responses and seemed to reduce the risk of disease relapse in patients with fully resected melanoma. This study examines the clinical and immunologic efficacy of the same vaccine in patients with advanced metastatic melanoma.

EXPERIMENTAL DESIGN

Delayed-type hypersensitivity responses, circulating NY-ESO-1-specific CD4(+) and CD8(+) T cells, and proportions of regulatory T cells (Treg) were assessed in patients.

RESULTS

In contrast to patients with minimal residual disease, advanced melanoma patients showed no clinical responses to vaccination. Although strong antibody responses were mounted, the generation of delayed-type hypersensitivity responses was significantly impaired. The proportion of patients with circulating NY-ESO-1-specific CD4(+) T cells was also reduced, and although many patients had CD8(+) T cells specific to a broad range of NY-ESO-1 epitopes, the majority of these responses were preexisting. Tregs were enumerated in the blood by flow cytometric detection of cells with a CD4(+)CD25(+)FoxP3(+) and CD4(+)CD25(+)CD127(-) phenotype. Patients with advanced melanoma had a significantly higher proportion of circulating Treg compared with those with minimal residual disease.

CONCLUSIONS

Our results point to a tumor-induced systemic immune suppression, showing a clear association between the stage of melanoma progression, the number of Treg in the blood, and the clinical and immunologic efficacy of the NY-ESO-1 ISCOMATRIX cancer vaccine.

Interactions between stem cells and their niche in the Drosophila ovary

The Drosophila ovary contains at least three types of active stem cells, namely, germ-line stem cells (GSCs), escort stem cells (ESCs), and follicular stem cells (FSCs), which work together to efficiently assemble egg chambers. Among the three stem cell types, the GSC is among the first shown to be controlled by the niche due to its easy identification and welldefined surrounding cells. We have shown that the niche controls GSC self-renewal, anchorage, aging, and competition, and the GSC also signals back to the niche for its maintenance. The FSC is an attractive model for studying epithelial stem cell regulation and signal integration because we have shown that it resembles mammalian epithelial stem cells and requires multiple signaling pathways for its self-renewal. In this chapter, we have highlighted the findings of our studies on interactions between Drosophila ovarian stem cells and their niches during normal development and aging and on stem cell competition for niche occupancy. We further discuss their implications in general stem cell biology and future directions in this exciting area.

Mucosal insulin vaccination for type 1 diabetes prevention

Mucosal administration of autoantigen, if efficacious, is an attractive therapeutic approach for prevention of type 1 diabetes. It can prevent or delay autoimmune diabetes in animal models, but although shown to be safe has not yet been proven effective in human studies. Efficacy may depend upon the dose and route at which antigen is administered, the stage in type 1 diabetes pathogenesis at which treatment is initiated, and the study cohort that is treated. Here we address these issues and propose a clinical translation possibility for mucosal insulin administration in genetically at risk individuals.

Immunization of malignant melanoma patients with full-length NY-ESO-1 protein using TLR7 agonist imiquimod as vaccine adjuvant

T cell-mediated immunity to microbes and to cancer can be enhanced by the activation of dendritic cells (DCs) via TLRs. In this study, we evaluated the safety and feasibility of topical imiquimod, a TLR7 agonist, in a series of vaccinations against the cancer/testis Ag NY-ESO-1 in patients with malignant melanoma. Recombinant, full-length NY-ESO-1 protein was administered intradermally into imiquimod preconditioned sites followed by additional topical applications of imiquimod. The regimen was very well tolerated with only mild and transient local reactions and constitutional symptoms. Secondarily, we examined the systemic immune response induced by the imiquimod/NY-ESO-1 combination, and show that it elicited both humoral and cellular responses in a significant fraction of patients. Skin biopsies were assessed for imiquimod's in situ immunomodulatory effects. Compared with untreated skin, topical imiquimod induced dermal mononuclear cell infiltrates in all patients composed primarily of T cells, monocytes, macrophages, myeloid DCs, NK cells, and, to a lesser extent, plasmacytoid DCs. DC activation was evident. This study demonstrates the feasibility and excellent safety profile of a topically applied TLR7 agonist used as a vaccine adjuvant in cancer patients. Imiquimod's adjuvant effects require further evaluation and likely need optimization of parameters such as formulation, dose, and timing relative to Ag exposure for maximal immunogenicity.

LUD 00-009: phase 1 study of intensive course immunization with NY-ESO-1 peptides in HLA-A2 positive patients with NY-ESO-1-expressing cancer

NY-ESO-1 is a cancer-testis antigen and an attractive target for immunotherapy in patients with different malignancies. Here we report the results of a phase I clinical study of intensive course NY-ESO-1 peptide vaccination, evaluating the safety, immunogenicity and clinical response in HLA-A2 positive patients with NY-ESO-1 expressing cancers. Of 20 patients enrolled in the trial, 14 completed at least 2 cycles of immunization and were evaluable for clinical and immunological response. Five of these evaluable patients were treated in cohort 1 (baseline seropositive) and 9 patients were treated in cohort 2 (baseline seronegative). During vaccination, NY-ESO-1-specific CD8+ T-cells were induced in 3 of 9 baseline seronegative patients. In patients with pre-existing antigen-specific CD8+ T-cells, their number increased or remained stable. In contrast to previous immunization protocols with less intensive immunization schedules, we observed a rapid induction of high magnitude NY-ESO-1 peptide-specific T-cell responses detectable already on day 15-22 of immunization. A specific immune response of high magnitude and early onset may be more effective in eliminating minimal residual disease in adjuvant treatment situations and in preventing tumor progression due to immune escape mechanisms.

P300 plays a role in p16(INK4a) expression and cell cycle arrest

As a cyclin-dependent kinase inhibitor, p16(INK4a) plays a key role in cell cycle progression and cellular differentiation, and its expression is frequently altered in human cancers through epigenetically mediated transcriptional silencing. In this report, we demonstrate that p300 was able to induce cell cycle arrest, and this process was reversed by p16(INK4a) silencing by RNA interference in HeLa cells. We also show that p300 was involved in activation of p16(INK4a) expression in 293T cells. Specifically, p300 cooperated with Sp1 to stimulate both p16(INK4a) promoter activity and mRNA expression. Co-immunoprecipitation and mammalian two-hybrid assays revealed that p300 and Sp1 formed a complex through interaction between the Q domain of p300 and the N-terminal domain of Sp1. The chromatin immunoprecipitation assays verified that p300 was recruited to p16(INK4a) promoter, and the histone acetyltransferase domain of p300 participated in p16(INK4a) activation through inducing hyperacetylation of histone H4 at p16(INK4a) gene. These data suggest that p300 plays a critical role in transcriptional regulation of p16(INK4a) and in cell cycle arrest.

Vaccination with an NY-ESO-1 peptide of HLA class I/II specificities induces integrated humoral and T cell responses in ovarian cancer

NY-ESO-1 is a "cancer-testis" antigen expressed in epithelial ovarian cancer (EOC) and is among the most immunogenic tumor antigens defined to date. The NY-ESO-1 peptide epitope, ESO(157-170), is recognized by HLA-DP4-restricted CD4+ T cells and HLA-A2- and A24-restricted CD8+ T cells. To test whether providing cognate helper CD4+ T cells would enhance the antitumor immune response, we conducted a phase I clinical trial of immunization with ESO(157-170) mixed with incomplete Freund's adjuvant (Montanide ISA51) in 18 HLA-DP4+ EOC patients with minimal disease burden. NY-ESO-1-specific Ab responses and/or specific HLA-A2-restricted CD8+ and HLA-DP4-restricted CD4+ T cell responses were induced by a course of at least five vaccinations at three weekly intervals in a high proportion of patients. There were no serious vaccine-related adverse events. Vaccine-induced CD8+ and CD4+ T cell clones were shown to recognize NY-ESO-1-expressing tumor targets. T cell receptor analysis indicated that tumor-recognizing CD4+ T cell clones were structurally distinct from non-tumor-recognizing clones. Long-lived and functional vaccine-elicited CD8+ and CD4+ T cells were detectable in some patients up to 12 months after immunization. These results confirm the paradigm that the provision of cognate CD4+ T cell help is important for cancer vaccine design and provides the rationale for a phase II study design using ESO(157-170) epitope or the full-length NY-ESO-1 protein for immunotherapy in patients with EOC.

Phase I trial of huA33 antibody plus 5-fluorouracil (5FU), leucovorin, and oxaliplatin in patients with metastatic colorectal cancer [LUD2003–005]

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Background: The selective targeting of tumors with monoclonal antibodies (mAb) has emerged as a new therapeutic approach in cancer therapy with the A33 glycoprotein being a promising target in colorectal cancer. Specific tumor localization and low toxicity of a humanised A33 specific mAb (huA33) has previously been demonstrated in patients with colorectal carcinoma. In the present study, we determined the safety and efficacy of the combination of huA33 and 5FU plus leucovorin and oxaliplatin (FOLFOX-4) in patients with metastatic colorectal cancer. Methods: Patients had to present with metastatic colorectal cancer with an expected survival of at least 4 months and no more than 2 different pre-treatment regimens. Patients were excluded if they had previously received oxaliplatin or huA33 mAb. Eligible patients received huA33 (10 mg/m2) by iv infusion weekly for 12 weeks (cycle 1). On study day 15, standard FOLFOX-4 chemotherapy was administered every 2 weeks for 10 weeks. Responding patients received a second cycle of weekly huA33 (10 mg/m2) and biweekly FOLFOX-4 chemotherapy. Results: A total of 19 patients (11 female, 8 male) with a median age of 60 years entered the study. 5 patients had received prior chemotherapy, 2 radiation therapy and 18 surgery. Toxicities observed were as expected for FOLFOX-4 treatment alone with hematological side effects to be most prominent and included (only G3 and G4) 1 anemia and 10 neutropenias. The addition of huA33 to FOLFOX-4 did not change the pattern of known non-hematological toxicities with a low rate (14%) of huA33 mAb associated allergic reactions. One sudden death occurred at cycle five that was neither therapy nor disease related. Within the 16 patients currently available for response assessment, the overall response rate was 38% with 1 CR, 5 PR and 5 disease stabilizations. Conclusion: The combination of FOLFOX-4 as standard chemotherapy for this cohort of patients in combination with the humanized A33 antibody did not increase toxicities and was well tolerated. The overall response rate of 38% is in the response range published so far for the FOLFOX-4 regimen in this setting and warrants further analysis in a larger cohort of patients.

[Table: see text]

Vaccination with NY-ESO-1 protein and CpG in Montanide induces integrated antibody/Th1 responses and CD8 T cells through cross-priming

The use of recombinant tumor antigen proteins is a realistic approach for the development of generic cancer vaccines, but the potential of this type of vaccines to induce specific CD8(+) T cell responses, through in vivo cross-priming, has remained unclear. In this article, we report that repeated vaccination of cancer patients with recombinant NY-ESO-1 protein, Montanide ISA-51, and CpG ODN 7909, a potent stimulator of B cells and T helper type 1 (Th1)-type immunity, resulted in the early induction of specific integrated CD4(+) Th cells and antibody responses in most vaccinated patients, followed by the development of later CD8(+) T cell responses in a fraction of them. The correlation between antibody and T cell responses, together with the ability of vaccine-induced antibodies to promote in vitro cross-presentation of NY-ESO-1 by dendritic cells to vaccine-induced CD8(+) T cells, indicated that elicitation of NY-ESO-1-specific CD8(+) T cell responses by cross-priming in vivo was associated with the induction of adequate levels of specific antibodies. Together, our data provide clear evidence of in vivo cross-priming of specific cytotoxic T lymphocytes by a recombinant tumor antigen vaccine, underline the importance of specific antibody induction for the cross-priming to occur, and support the use of this type of formulation for the further development of efficient cancer vaccines.