Identification of a new HLA-B*40 allele, HLA-B*4081, in a Chinese individual

A novel human leukocyte antigen (HLA)-B*40 allele, officially named B*4081, was identified during routine high-resolution sequence-based typing in a Chinese potential hematopoietic stem cell transplantation donor. The HLA-B*4081 allele shows one nucleotide difference from B*400101 in exon 2 at nucleotide position 124 where G-->C (codon 18 GGG-->CGG) resulting in a coding change, 18Gly is changed to Arg, this is a unique nucleotide change among the HLA class I alleles, suggesting a point mutation mechanism.

Transcriptome analysis in mouse tumors induced by Ret-MEN2/FMTC mutations reveals subtype-specific role in survival and interference with immune surveillance

Activating mutations in the Ret proto-oncogene are responsible for occurrence of multiple endocrine neoplasia (MEN) type 2A and 2B, and familial medullary thyroid carcinoma (FMTC). A striking genotype-phenotype correlation between the mutated RET codon and clinical manifestation implies that tumorigenesis is conditioned by the type of mutation. We investigated gene expression profiles between and within distinct MEN2 subtypes through whole-genome microarray analysis in tumors induced by NIH-3T3 cells transformed with defined RET-MEN2A (C609Y, C634R), MEN2B, (A883F, M918T), and FMTC (Y791F) mutations. Expression profiling identified a statistically significant modification of 1494 genes, 628 down- and 866 upregulated in MEN2B compared with MEN2A/FMTC tumors. By contrast, no obvious alterations were observed among individual MEN2B and MEN2A type mutations, or between MEN2A and FMTC. Functional clustering of differential genes revealed RET-MEN2B specific upregulation of genes associated with novel growth and survival pathways. Intriguingly, RET-MEN2A/FMTC-specific tumors were characterized by a considerable number of genes involved in the host antitumor immune response via stimulation of natural killer/T-cell proliferation, migration, and cytotoxicity, which were completely absent in RET-MEN2B related cancers. QPCR on tumors versus cultured NIH-RET cell lines demonstrated that they are largely attributed to the host innate immune system, whereas expression of CX3CL1 involved in leukocyte recruitment is exclusively RET-MEN2A/FMTC tumor cell dependent. In correlation, massive inflammatory infiltrates were apparent only in tumors carrying MEN type 2A/FMTC mutations, suggesting that RET-MEN2B receptors specifically counteract immune infiltration by preventing chemokine expression, which may contribute to the different clinical outcome of both subtypes.

Clinical Utility of Magnetic Resonance Thermal Imaging (MRTI) For Realtime Guidance of Deep Hyperthermia

A critical need has emerged for volumetric thermometry to visualize 3D temperature distributions in real time during deep hyperthermia treatments used as an adjuvant to radiation or chemotherapy for cancer. For the current effort, magnetic resonance thermal imaging (MRTI) is used to measure 2D temperature rise distributions in four cross sections of large extremity soft tissue sarcomas during hyperthermia treatments. Novel hardware and software techniques are described which improve the signal to noise ratio of MR images, minimize motion artifact from circulating coupling fluids, and provide accurate high resolution volumetric thermal dosimetry. For the first 10 extremity sarcoma patients, the mean difference between MRTI region of interest and adjacent interstitial point measurements during the period of steady state temperature was 0.85°C. With 1min temporal resolution of measurements in four image planes, this non-invasive MRTI approach has demonstrated its utility for accurate monitoring and realtime steering of heat into tumors at depth in the body.

Expression of ER-a36, a novel variant of estrogen receptor a, and resistance to tamoxifen treatment in breast cancer

Abstract #3037

Background: Recently, a 36 kDa variant of estrogen receptor a (ER-a66), ER-a36, has been identified and cloned. ER-a36 predominantly localizes on the plasma membrane and in the cytoplasm and mediates a membrane-initiated “nongenomic” signaling pathway. In this study, we investigated the association between ER-a36 expression and tamoxifen resistance in breast cancer patients.
 Methods: ER-a36 protein expression in tumors from 710 breast cancer patients with a median follow-up of 7.9 years was assessed using immunohistochemistry (IHC) assay. Survival curves were compared using the log-rank test and multivariate analysis was performed using Cox model. All statistical tests were two-sided.
 Results: Among the patients with ER-a66 positive tumors who received tamoxifen treatment (n=307), overexpression of ER-a36 was associated with poorer disease-free survival (DFS) and disease-specific survival (DSS) and remained as an unfavorable independent factor of survival in multivariate analyses (DFS: HR=2.27; 95% CI= 1.40 to 3.68; P=. 001; DSS: HR=2.42; 95% CI= 1.37 to 4.28; P= .002). In contrast, among patients with ER-a66 positive tumors who did not receive tamoxifen (n=129), ER-a36 expression was not associated with survival, indicating a correlation between ER-a36 expression and tamoxifen resistance. Furthermore, ER-a36 expression was not associated with survival in ER-a66 negative tumors whether the patients received tamoxifen (n=73) or not (n=149). Our in vitro experiments with MCF7/ER36 cells also confirmed that high ER-a36 expression resulted in tamoxifen resistance.
 Conclusions: Patients with ER-a66 positive tumors that also express high levels of ER-a36 are less likely to benefit from tamoxifen treatment. ER-a36 is an important predictive marker for tamoxifen therapy in ER-a66 positive breast cancer patients.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 3037.

Split-ring-resonator-coupled enhanced transmission through a single subwavelength aperture

We report the enhanced transmission of electromagnetic waves through a single subwavelength aperture by using a split-ring resonator (SRR) at microwave frequencies. By placing a single SRR at the near field of the aperture, strongly localized electromagnetic fields are effectively coupled to the aperture with a radius that is 20 times smaller than the resonance wavelength (r/lambda=0.05). We obtained 740-fold transmission enhancement by exciting the electric resonance of SRR. A different coupling mechanism, through the magnetic resonance of SRR, is also verified to lead to enhanced transmission.

The influence of intraoperative tumor rupture on recurrence risk in Stage Ic epithelial ovarian cancer

OBJECTIVE

To characterize the outcomes of patients with Stage Ic epithelial ovarian carcinoma, taking into consideration the criteria that were used to assign staging. We hypothesized that tumor rupture is a less ominous prognosticator in early-stage epithelial ovarian cancer than malignant washings or ovarian surface invasion.

METHODS

A retrospective analysis of patients diagnosed with Stage I epithelial ovarian carcinoma at the University of Minnesota between 1990 and 2005 was carried out. Information was collected about demographics, diagnosis date, stage, grade, adjuvant treatment, last contact date and status at last contact. Statistical analysis was performed using the Kaplan-Meier method and the Cox proportion hazard model.

RESULTS

One hundred and seventeen patients with Stage I epithelial ovarian cancer were identified and included in this review. Three distinct groups of patients were considered: 1) patients with Stage Ic cancers, so-assigned because of intraoperative tumor rupture only, 2) patients with Stage Ic cancers, so-assigned for any other reason(s) than rupture alone, and 3) patients with Stages Ia and Ib cancers. The recurrence risk of patients in group 1 was not significantly different from that of patients in groups 2 or 3 (p values 0.13 and 0.69, respectively), although a trend toward decreased risk of recurrence was seen in patients from group 1 compared to both other groups.

CONCLUSIONS

In our cohort of patients, the risk of tumor recurrence in patients with Stage Ic epithelial ovarian cancer, so-assigned because of intraoperative rupture alone, is not significantly different from the two other groups of patients with Stage I disease.

42 ASSISTED ENUCLEATION IN GOLDEN HAMSTER OOCYTES TREATED WITH COLCHICINE AND DEMECOLCINE

The golden hamster is an excellent experimental animal in many research fields. In an effort to establish experimental protocols necessary for cloning golden hamsters, optimized conditions for induced cytoplasmic protrusion and assisted enucleation of golden hamster oocytes with different concentrations of colchicine and demecolcine were examined in this study. The Golden hamsters (female, six weeks of age) were superovulated with eCG (30 IU, ip) followed by hCG (30 IU, ip) at intervals of 72 h. Hamsters were sacrificed at 13.5 h, 15 h and 18 h after hCG injection. The different ages of cumulus–oocyte complexes (COCs) were collected from oviducts and cumulus cells were removed with 0.1% hyaluronidase. (1) denuded oocytes of different ages were treated with 2.5 μg mL–1, 5 μg mL–1, and 10 μg mL–1 of colchicine for 4 h in M199TE, and they were examined each hour; (2) denuded oocytes of different ages were treated with 0.02 μg mL–1, 0.04 μg mL–1, 0.06 μg mL–1, 0.1 μg mL–1, 0.2 μg mL, 0.4 μg mL–1, and 0.6 μg mL–1 of demecolcine for 1 h in M199TE, and they were examined every 15 min; 3) according to the results of processes (1) and (2), cytoplasmic protrusions of oocytes treated with 10 μg mL–1 of colchicine (60 oocytes) or 0.4 μg mL–1 demecolcine (88 oocytes) for 1 h were removed with a micromanipulation pipette. Then the oocytes were examined by being stained with Hoechst 33342, and the percentage of assisted enucleation was compared with that of blind enucleation in which position of the chromosomes was indirectly determined by the location of the first polar body. The results showed that: (1) about 90% of oocytes at 13.5 h and 15 h post hCG injection were induced to form protrusions under the treatment of 10 μg mL–1 of colchicine for 1 h; (2) oocytes of 13.5 h post hCG were very sensive to demecolcine, even the treatment of 0.02 μg mL–1 for 1 h could also induce cytoplasmic protrusions (45.38% of 31 oocytes); (3) when treated with 0.4 μg mL–1 of demecolcine for 1 h, the cytoplasmic protrusion rate of oocytes of 13.5 h–18 h post-hCG could reach to 99–100%; (4) when the cytoplasmic protrusions induced by 10 μg mL–1 of colchicine or 0.4 μg mL–1 of demecolcine for 1 h were removed, assisted enucleation rates were over 80%, significantly higher (P < 0.05) than blind enucleation (31.53% of 60 oocytes). In conclusion, the results of this study demonstrate that both colchicine and demecolcine can induce the hamster oocytes to form cytoplasmic protrusions. The treatments of 10 μg mL–1 of colchicine or 0.4 μg mL–1 of demecolcine for 1 h were the best conditions to induce oocytes (13.5 h–18 h post hCG) to form protrusion. Also, the assisted enucleation rate with colchicine and demecolcine is much higher than that of blind enucleation. These results define conditions for chemical assisted enucleation and should facilitate the development of cloned golden hamsters as an animal model for human diseases.

Origin of the spin density wave instability in AFe2As2 (A=Ba,Sr) as revealed by optical spectroscopy

We performed optical spectroscopy measurement on single crystals of BaFe2As2 and SrFe2As2, the parent compounds of FeAs-based superconductors. Both are found to be quite metallic with fairly large plasma frequencies at high temperature. Upon entering the spin-density-wave state, the formation of partial energy gaps was clearly observed with the surprising presence of two different energy scales. A large part of the Drude component was removed by the gapping of Fermi surfaces. Meanwhile, the carrier scattering rate was even more dramatically reduced. We elaborate that the spin-density-wave instability is more likely to be driven by the Fermi surface nesting of itinerant electrons than a local-exchange mechanism.

Nanoparticle delivery of anti-metastatic NM23-H1 gene improves chemotherapy in a mouse tumor model

Gene therapy provides a promising approach for cancer treatment. Earlier studies suggested that poly-L-lysine-modified iron oxide nanoparticles (IONP-PLL) might be a promising gene delivery system that can transfect DNA efficiently in vitro and in vivo. In this study we used IONP-PLL as gene carriers to deliver the NM23-H1 gene, the first suppressor gene of cancer metastasis, to tumor cells in vivo. The intravenous injection of IONP-PLL carrying NM23-H1-GFP plasmid DNA significantly extended the survival time of an experimental pulmonary metastasis mouse model. In the IONP-PLL/NM23-H1-GFP-treated group, metastasis was clearly suppressed compared with the group treated with free NM23-H1-GFP plasmid. Furthermore, this gene therapy combined with cyclophosphamide treatment resulted in longer survival times and greater suppression of metastasis growth. In conclusion, treatment with IONP-PLL nanoparticles incorporating the NM23-H1gene is an efficient gene therapy method, and it is even more effective in combination with chemotherapy. This approach appears to be a promising strategy for treatment of metastatic tumors.

Origin of the spin density wave instability in AFe2As2 (A=Ba,Sr) as revealed by optical spectroscopy

We performed optical spectroscopy measurement on single crystals of BaFe2As2 and SrFe2As2, the parent compounds of FeAs-based superconductors. Both are found to be quite metallic with fairly large plasma frequencies at high temperature. Upon entering the spin-density-wave state, the formation of partial energy gaps was clearly observed with the surprising presence of two different energy scales. A large part of the Drude component was removed by the gapping of Fermi surfaces. Meanwhile, the carrier scattering rate was even more dramatically reduced. We elaborate that the spin-density-wave instability is more likely to be driven by the Fermi surface nesting of itinerant electrons than a local-exchange mechanism.

Training-induced vascular adaptations to ischemic muscle

Peripheral arterial insufficiency is a progressive degenerative disease associated with an increased morbidity and mortality. It decreases exercise tolerance and often presents with symptoms of intermittent claudication. Enhanced physical activity is one of the most effective means of improving the life of affected patients. While this occurs for a variety of reasons, vascular remodeling can be an important means for improved oxygen exchange and blood flow delivery. Relevant exercise-induced signals stimulate angiogenesis, within the active muscle (e.g. hypoxia), and arteriogenesis (enlargement of pre-existing vessels via increased shear stress) to increase oxygen exchange and blood flow capacity, respectively. Evidence from pre-clinical studies shows that the increase in collateral blood flow observed with exercise progresses over time of training, is accompanied by significant enlargement of isolated collateral vessels, and enhances the responses observed with angiogenic growth factors (e.g. VEGF, FGF-2). Thus, enhanced physical activity can be an effective means of enlarging the structure and function of the collateral circuit. Interestingly, disrupting normal NO production (via L-NAME) eliminates this increase in collateral blood flow induced by training, but does not disturb the increase in muscle capillarity within the active muscle. Similarly, inhibiting VEGF receptor kinase activity eliminates the increase in collateral-dependent blood flow, and lessens, but does not eliminate, angiogenesis within the calf muscle. These findings illustrate distinctions between the processes influencing angiogenesis and arteriogenesis. Further, sympathetic modulation of the collateral circuit does not eliminate the increase in collateral circuit conductance induced by exercise training. These findings indicate that structural enlargement of the collateral vessels is essential to realize the increase in collateral-dependent blood flow capacity caused by exercise training. This raises the potential that meaningful vascular remodeling can occur in patients with intermittent claudication who actively participate in exercise training.

CD8+ T-Cell depletion and rapamycin synergize with combined coreceptor/stimulation blockade to induce robust limb allograft tolerance in mice

The growing development of composite tissue allografts (CTA) highlights the need for tolerance induction protocols. Herein, we developed a mouse model of heterotopic limb allograft in a stringent strain combination in which potentially tolerogenic strategies were tested taking advantage of donor stem cells in the grafted limb. BALB/c allografts were transplanted into C57BL/6 mice treated with anti-CD154 mAb, nondepleting anti-CD4 combined to either depleting or nondepleting anti-CD8 mAbs. Some groups received additional rapamycin. Both depleting and nondepleting mAb combinations without rapamycin only delayed limb allograft rejection, whereas the addition of rapamycin induced long-term allograft survival in both combinations. Nevertheless, robust donor-specific tolerance, defined by the acceptance of a fresh donor-type skin allograft and simultaneous rejection of third-party grafts, required initial CD8(+) T-cell depletion. Mixed donor-recipient chimerism was observed in lymphoid organs and recipient bone marrow of tolerant but not rejecting animals. Tolerance specificity was confirmed by the inability to produce IL-2, IFN-gamma and TNF-alpha in MLC with donor antigen while significant alloreactivity persisted against third- party alloantigens. Collectively, these results show that robust CTA tolerance and mixed donor-recipient chimerism can be achieved in response to the synergizing combination of rapamycin, transient CD8(+) T-cell depletion and costimulation/coreceptor blockade.

Structural and magnetic phase diagram of CeFeAsO(1- x)F(x) and its relation to high-temperature superconductivity

Recently, high-transition-temperature (high-Tc) superconductivity was discovered in the iron pnictide RFeAsO(1-x)F(x) (R, rare-earth metal) family of materials. We use neutron scattering to study the structural and magnetic phase transitions in CeFeAsO(1-x)F(x) as the system is tuned from a semimetal to a high-Tc superconductor through fluorine (F) doping, x. In the undoped state, CeFeAsO develops a structural lattice distortion followed by a collinear antiferromagnetic order with decreasing temperature. With increasing fluorine doping, the structural phase transition decreases gradually and vanishes within the superconductivity dome near x=0.10, whereas the antiferromagnetic order is suppressed before the appearance of superconductivity for x>0.06, resulting in an electronic phase diagram remarkably similar to that of the high-Tc copper oxides. Comparison of the structural evolution of CeFeAsO(1-x)F(x) with other Fe-based superconductors suggests that the structural perfection of the Fe-As tetrahedron is important for the high-Tc superconductivity in these Fe pnictides.