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Purpose To develop MR based real-time gastrointestinal 19-Fluorine (19F) catheter tracking and visualization allowing for real-time detection and feedback of 3D catheter shape and movement as well as catheter-driven adjustments of 1H imaging geometry parameters. Methods Data were acquired on a 3T clinical system using 3D Golden Angle radial sampling. Two gastrointestinal catheters incorporating four fiducial 19F markers (65 or 50 µL marker volume) were tracked while being pulled through a gel phantom by an operator inside the MR room with velocities of 2–18 mm/s. During continuous acquisition, k-space profiles were transferred in real-time to an external computer for concurrent reconstruction of 3D 19F images and detection and visualization of marker positions. Based on αthe marker positions, automatic adjustments of 1H imaging planes to facilitate targeted anatomical scanning was implemented. Results Mean tracking reliabilities were 94.5 and 83.6% (catheters 1 and 2) for temporal resolutions 185–740 ms. Reconstruction times of 196 ms were achieved. Real-time visual feedback allowed the operator to accurately control the catheter movement. Catheter-guidance for 1H imaging was reliable. Conclusion The presented real-time 19F MR based framework for the tracking of 19F labeled devices is applicable to combined 19F and 1H MRI guidance of gastrointestinal devices in vivo. Magn Reson Med 71:302–307, 2014. © 2013 Wiley Periodicals, Inc.

The semisynthetic vitamin E derivative alpha-tocopheryloxyacetic acid (α-TEA) induces tumor cell apoptosis and may offer a simple adjuvant supplement for cancer therapy if its mechanisms can be better understood. Here we report that α-TEA also triggers tumor cell autophagy and that it improves cross-presentation of tumor antigens to the immune system. α-TEA stimulated both apoptosis and autophagy in murine mammary and lung cancer cells and inhibition of caspase-dependent apoptosis enhanced α-TEA–induced autophagy. Cell exposure to α-TEA generated double-membrane–bound vesicles indicative of autophagosomes, which efficiently cross-primed antigen-specific CD8+ T cells. Notably, vaccination with dendritic cells pulsed with α-TEA–generated autophagosomes reduced lung metastases and increased the survival of tumor-bearing mice. Taken together, our findings suggest that both autophagy and apoptosis signaling programs are activated during α-TEA–induced tumor cell killing. We suggest that the ability of α-TEA to stimulate autophagy and enhance cross-priming of CD8+ T cells might be exploited as an adjuvant strategy to improve stimulation of antitumor immune responses. Cancer Res; 72(14); 3535–45. ©2012 AACR.

Alpha-tocopheryloxy acetic acid (α-TEA) is an ether derivative of vitamin E and has been shown to suppress tumor growth in various murine and human xenograft tumor models, including melanoma, breast, lung, prostate, and ovarian cancers. The purpose of this study was to assess its safety and pharmacokinetics after repeat dosing in a preclinical murine model. Male and female mice received α-TEA doses of 100, 300, or 1500 mg/kg/day by daily oral gavage for 28 days. α-TEA serum levels were determined weekly by high-performance liquid chromatography with mass spectrometric detection. After 28 days of dosing, complete blood counts were taken, blood chemistry was analyzed, and histology was performed. Pharmacokinetic parameters were determined after single dosing. There was no mortality, and we found no clinical signs of toxicity in any of the α-TEA doses tested. Histopathological evaluation of major organs (heart, lung, kidney, liver, spleen, jejunum, ileum, and cecum) revealed no significant α-TEA treatment-related lesions. Blood counts revealed low-grade anemia but no other significant differences between treatment and control groups. Blood chemistry revealed moderate liver toxicity that was dose dependent and was absent in the lowest dose group. There were no significant sex-specific differences in the toxicity profile. The half-life of orally administered α-TEA was determined to be 52 h. This is the first report comprehensively evaluating the toxicity profile of this novel anticancer drug and will facilitate the design of clinical trials to evaluate the safety and antitumor efficacy of α-TEA in patients with cancer.

PURPOSE: Although breast dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) demonstrates high sensitivity for malignant tumor detection, a major limitation is the relative low specificity, resulting in many false-positive diagnoses of suspicious lesions (BI-RADS assessment of 4 or 5) in clinical practice and consequently producing a relatively low positive predictive value (PPV) for biopsies. The most enhanced areas in the malignant tumors show a typical washout (WO) kinetic feature for the postcontrast signal intensity time courses and also correlate with microvessel density. Benign proliferative breast diseases can also produce the WO curve, yielding an equivocal kinetic behavior for the benign lesions and rendering their diagnoses as suspicious lesions in clinical practice. Considering that tumor angiogenesis is essential to an aggressive cancer tumor growth, the authors hypothesize that the WO volume fraction, i.e., the total volume of the WO voxels that demonstrate the WO curve within the tumor, is relatively large for malignant tumors in comparison to that for benign lesions. In this study, the authors present a lesion fractional volume WO kinetic analysis for improving the characterization of suspicious breast lesions. METHODS: A method to automatically detect the boundary of a manually selected contrast-enhanced lesion was introduced and tested, utilizing the signal intensity difference between the contrast-enhanced lesion and its surrounding tissues. The kinetic features of the postcontrast signal intensity time courses were quantitatively analyzed voxel-by-voxel with emphasis on the examination of the WO behavior. The WO volume fraction relative to the whole lesion volume was introduced and tested as a biomarker for improving the characterization of suspicious breast lesions. The sample for this test consisted of 28 suspicious lesions with correlative histopathology reports available. The lesions included 10 malignant tumors and 18 benign lesions, yielding a 35.7% PPV of the biopsies. RESULTS: The semi-automatic method produced an objective volume of interest for each lesion with voxelwise-quantified kinetic features. With an optimal choice of kinetic analysis, the mean and standard deviation of the WO volume fraction were 59.1 ± 13.1 (%) with the range from 41.0% to 80.7% for the malignant tumors and 31.4 ± 20.5 (%) with the range between 3.3% and 71.6% for the benign lesions, respectively. The WO volume fraction was significantly larger (p

A combined (19)F and (1)H MRI framework for the assessment of human intestinal transit and motor function is presented. This framework consists of silicone coated polychlorotrifluoroethylene capsules filled with perfluoro-[15]-crown-5-ether as (19)F marker, a flexible (19)F surface coil and a (19)F projection imaging sequence, allowing for real-time tracking of a single or multiple capsules. The capsules (length 11.5 mm, O 7.2 mm) contain 140 μL perfluoro-[15]-crown-5-ether and were tested for cytotoxicity and leakage prior to oral administration. A balanced SSFP projection sequence was implemented, yielding a temporal resolution of 133 ms. Optional multi-frequency excitation, allowing for interleaved tracking of differently labeled (19)F capsules, was incorporated. The passage of the (19)F capsules through intestinal sections was monitored in two healthy volunteers. Capsule coordinates were successfully coregistered with anatomical reference scans. Intestinal motility, residence times, lengths and forward velocities were determined. Simultaneous tracking of two capsules allowed for the assessment of peristaltic patterns with correction for respiratory motion. By providing the means for real-time multiple capsule tracking and high resolution anatomical imaging, the presented multinuclear imaging framework has the potential to provide important supplemental information for physiological and pharmaceutical research.

We recently demonstrated the antitumor efficacy of orally administered α-tocopheryloxyacetic acid (α-TEA), a redox silent and nonhydrolyzable derivative of naturally occurring vitamin E. In order to move α-TEA closer to the clinic to benefit patients with breast cancer, the present study had two goals. First, to determine the minimal effective treatment dose; and second, to test the efficacy of dietary administration of α-TEA in the clinically relevant MMTV-PyMT mouse model of spontaneous breast cancer that more closely resembles human disease. The minimal effective dose of α-TEA was evaluated in the transplantable 4T1 tumor model and we show a dose-dependent decrease of primary tumor growth and reduction of metastatic spread to the lung. Six-week-old MMTV-PyMT mice were treated with oral α-TEA for 9 weeks, with no apparent signs of drug toxicity. The α-TEA treatment delayed tumor development and significantly slowed tumor progression, resulting in a 6-fold reduction of the average cumulative tumor size. In addition, oral α-TEA caused an 80% reduction in spontaneous metastases. In situ analysis of tumor tissue identified apoptosis as an important mechanism of α-TEA–mediated tumor suppression in addition to inhibition of tumor cell proliferation. This study shows, for the first time, the ability of orally administered α-TEA to delay tumor onset and to inhibit the progression and metastatic spread of a clinically relevant model of spontaneous breast cancer. Our finding of the high efficacy in this tumor model highlights the translational potential of oral α-TEA therapy. [Mol Cancer Ther 2009;8(6):1570–78]

A bigenic MUC1.Tg/MIN mouse model was developed by crossing Apc/(MIN/+) (MIN) mice with human MUC1 transgenic mice to evaluate MUC1 antigen-specific immunotherapy of intestinal adenomas. The MUC1.Tg/MIN mice developed adenomas at a rate comparable to that of MIN mice and had similar levels of serum MUC1 antigen. A MUC1-based vaccine consisting of MHC class I-restricted MUC1 peptides, a MHC class II-restricted pan-helper peptide, unmethylated CpG oligodeoxynucleotide and GM-CSF caused flattening of adenomas and significantly reduced the number of large adenomas. Immunization was successful in generating a MUC1-directed immune response evidenced by increased MUC1 peptide-specific anti-tumor cytotoxicity and IFN-gamma secretion by lymphocytes.

The ability of the vitamin E (RRR-α-tocopherol) derivatives α-tocopheryl succinate (α-TOS) and α-tocopheryloxyacetic acid (α-TEA) to suppress tumor growth in preclinical animal models has recently led to increased interest in their potential use for treating human cancer. To make the use of these vitamin E analogues more clinically relevant, we compared the antitumor efficacy of orally and i.p. delivered forms of α-TEA and α-TOS against a murine mammary cancer (4T1) that bears resemblance to human breast cancer because of its poor immunogenicity and high metastatic potential. In cell culture studies, we showed that both compounds inhibited tumor colony formation and induced apoptotic death of tumor cells. To avoid solubility concerns associated with the hydrophobicity of α-TEA and α-TOS, we used the vesiculated forms of α-TEA (Vα-TEA) and α-TOS (Vα-TOS) for the in vivo tumor studies. Both compounds inhibited the growth of preestablished 4T1 tumors when given i.p. However, when given by oral gavage, only the esterase-resistant Vα-TEA was able to suppress primary tumor growth and reduce lung metastasis. To make this approach more translatable to the clinic, α-TEA was incorporated into the diet and fed to tumor-bearing mice. We report here for the first time that dietary α-TEA delivery significantly inhibited primary tumor growth and dramatically reduced spontaneous metastatic spread to the lung in prophylactic and therapeutic settings. This study suggests that dietary α-TEA could prove useful as a relatively easy and effective modality for treating metastatic breast cancer. (Cancer Res 2006; 66(19): 9374-8)

Cyclooxygenase-2 (COX-2) is a rate-limiting enzyme in the synthesis of prostaglandins. It is over-expressed in multiple cancers and has been associated with diminished tumor immunity. Dendritic cells (DCs) are considered candidates for cancer immunotherapy due to their ability to process and present antigens to T cells and stimulate immune responses. However, DC-based vaccines have exhibited minimal effectiveness against established tumors. In this study, we evaluated the effect of short-term administration of the selective COX-2 inhibitor celecoxib on the efficacy of DC-based vaccines in preventing and treating established 4T1 murine mammary tumors. We show that dietary celecoxib alone significantly suppresses the growth of primary tumors and the incidence of lung metastases in the prophylactic setting but is less effective against pre-established tumors. However, we demonstrate that celecoxib administered after primary tumor establishment synergizes with tumor lysate-pulsed DC and the adjuvant, GM-CSF, to improve the antitumor immune response by suppressing primary tumor growth and markedly reducing the occurrence of lung metastases. This triple combination therapy elicits a tumor-specific immune response evidenced by elevated IFN-gamma and IL-4 secretion by CD4+ T cells and results in increased infiltration of CD4+ and CD8+ T cells to the tumor site. In addition, dietary celecoxib inhibits angiogenesis evidenced by decreased vascular proliferation within the tumor and serum vascular endothelial growth factor levels. These studies suggest that short-term celecoxib therapy in combination with DC vaccines may be safely used for treating metastatic breast cancer.

In this study, we evaluated the efficacy of vesiculated alpha-tocopheryl succinate (Valpha-TOS) in combination with non-antigen pulsed, nonmatured dendritic cells (nmDC) to treat pre-established tumors of the highly metastatic murine mammary cancer cell line 4T1. We demonstrated that Valpha-TOS in combination with non-antigen pulsed nmDC significantly inhibits the growth of established tumors in vivo and prolongs survival of treated mice. In addition, when initiated after resection of the established primary tumor, the combination treatment dramatically inhibits residual metastatic disease. The clinical response achieved with the combination therapy was correlated with increased interferon-gamma and interleukin-4 (IL-4) production by splenic lymphocytes and draining lymph node cells. Interestingly, when used in combination with Valpha-TOS, nmDC were as effective as tumor necrosis factor-alpha matured DC at inhibiting the growth of pre-established tumors. Valpha-TOS-induced cellular factors collected by high-speed centrifugation of supernatant from Valpha-TOS-treated tumor cells caused maturation of DC as evidenced by the up-regulation of co-stimulatory molecules and secretion of IL-12p70. These results demonstrate the potential usefulness of Valpha-TOS + DC chemo-immunotherapy in treating established primary mammary tumors as well as residual metastatic disease.

Stimulation of apoptosis has been reported as the primary mechanism of tumor cell death induced by alpha-tocopheryloxyacetic acid (α-TEA), an esterase-resistant, semi-synthetic derivative of vitamin E (R-R-R-α-tocopherol). New information now shows that α-TEA also triggers tumor cell autophagy and promotes antigen cross-presentation. Autophagosome-enriched fractions of α-TEA-treated tumor cells (α-TAGS) efficiently cross-primed antigen-specific CD8 (+) T cells and vaccination with dendritic cells (DC) pulsed with α-TAGS reduced lung metastases and increased survival of tumor-bearing mice. Taken together, these observations suggest that both autophagy and apoptosis signaling programs are activated in tumor cells by α-TEA treatment and may contribute to tumor cell death. We propose that autophagy-dependent enhancement of cross-presentation is a novel mechanism of α-TEA-mediated tumor immunity and that α-TEA can be exploited as an adjuvant to enhance the antitumor response.

To combine fluorine 19 ((19)F) magnetic resonance (MR) imaging and golden angle radial acquisition and to assess the feasibility of (19)F MR imaging golden angle-based tracking for catheter tracking applications and simultaneous three-dimensional (3D) intestinal tracking of ingested (19)F-labeled capsules in vivo.Approval from the local ethical committee and informed consent from the subject were obtained. In vitro studies were performed to assess (19)F MR imaging golden angle-based tracking reliability with regard to temporal resolution and different tracking strategies (boundary condition-free tracking, composite image-based tracking, and model-based tracking). In vivo performance of the method was investigated in one healthy volunteer on 2 days. On study day 1, a duodenal catheter incorporating five (19)F-labeled capsules was administered nasally, and its 3D movement was tracked inside the stomach and esophagus. On study day 2, three (19)F-labeled capsules were swallowed, and intestinal movement was tracked.Simultaneous in vivo 3D tracking of multiple (19)F-labeled capsules was successfully performed without incorporation of boundary conditions at a temporal resolution of 252 msec. Incorporation of boundary conditions with composite image-based tracking and model-based tracking increased tracking reliability and enabled temporal resolution as high as 108 msec.Use of (19)F MR imaging golden angle-based capsule tracking enables in vivo tracking of (19)F-labeled capsules and catheters at high temporal resolution. The presented method is applicable to physioanatomic studies of the gastrointestinal tract and shows potential for real-time tracking in interventional radiology.

Effective tumor immunotherapy may require not only activation of anti-tumor effector cells, but also abrogation of tumor-mediated immunosuppression. The cytokine TGF-β, is frequently elevated in the tumor microenvironment and is a potent immunosuppressive agent and promoter of tumor metastasis. OX40 (CD134) is a member of the TNF-α receptor superfamily and ligation by agonistic antibody (anti-OX40) enhances effector function, expansion, and survival of activated T cells. In this study, we examined the therapeutic efficacy and anti-tumor immune response induced by the combination of a small molecule TGF-β signaling inhibitor, SM16, plus anti-OX40 in the poorly immunogenic, highly metastatic, TGF-β-secreting 4T1 mammary tumor model. Our data show that SM16 and anti-OX40 mutually enhanced each other to elicit a potent anti-tumor effect against established primary tumors, with a 79% reduction in tumor size, a 95% reduction in the number of metastatic lung nodules, and a cure rate of 38%. This positive treatment outcome was associated with a 3.2-fold increase of tumor-infiltrating, activated CD8+ T cells, an overall accumulation of CD4+ and CD8+ T cells, and an increased tumor-specific effector T cell response. Complete abrogation of the therapeutic effect in vivo following depletion of CD4+ and CD8+ T cells suggests that the anti-tumor efficacy of SM16+ anti-OX40 therapy is T cell dependent. Mice that were cured of their tumors were able to reject tumor re-challenge and manifested a significant tumor-specific peripheral memory IFN-γ response. Taken together, these data suggest that combining a TGF-β signaling inhibitor with anti-OX40 is a viable approach for treating metastatic breast cancer.

Patients suffering from a heart valve deficiency are often treated by replacing the valve with an artificial or biological implant. In case of biological implants, the use of porcine heart valves is common. Quality assessment and inspection methods are mandatory to supply the patients (and also medical research) with only the best such xenograft implants thus reducing the number of follow-up surgeries to replace worn-up valves. We describe an approach for automatic in-vitro evaluation of prosthetic heart valves in an artificial circulation system. We show how to measure the orifice area during a heart cycle to obtain an orifice curve. Different quality parameters are then estimated on such curves.

Background Functional rehabilitation of patients afflicted with severe mandibular and maxillary alveolar atrophy might be challenging especially in malformed patients. Methods Treatment planning using sinus lifting and implant placement before Le Fort I maxillary osteotomy in a patient with severe mandibular and posterior maxillary alveolar atrophy and skelettal class-III conditions due to cleft palate are described. Results A full functional and esthetic rehabilitation of the patient was achieved by a stepwise surgical approach performed through sinus lifting as the primary approach followed by implant placement and subsequent Le Fort I maxillary osteotomy to correct the maxillo-mandibular relation. Conclusion Stabilisation of the maxillary complex by a sinus lifting procedure in combination with computer aided implant placement as preorthodontic planning procedure before Le Fort I maxillary osteotomy seems to be suitable in order to allow ideal oral rehabilitation especially in malformed patients.

Patients suffering from a tricuspid heart valve deficiency are often treated by replacing the valve with artificial or biological implants. In case of biological implants, the use of porcine heart valves is common. To supply patients with the best such xenograft implants, quality assessment and inspection methods for biological heart valves are necessary. We describe initial approaches to automatically testing tricuspid heart valves in-vitro in an artificial circulation system. We use two criteria to judge the quality of the valve, i.e. the evolution of the orifice area during a heart cycle and the fluttering of the valve leaflets in the stream.

The NEF gene is conserved among members of human and simian immunodeficiency viruses and may play an important role in viral pathogenesis. To determine the evolutionary dynamics and conservation of functionality of the human immunodeficiency virus type 1 (HIV-1) NEF gene during maternal-fetal transmission, we analyzed NEF sequences from seven mother-infant pairs following perinatal transmission, including a mother with infected twin infants. The NEF open reading frame was maintained in mother-infant isolates with a frequency of 86.2% following vertical transmission. While there was a low degree of viral heterogeneity and estimates of genetic diversity and high population growth rates of NEF sequences from mother-infant isolates, the infants' NEF sequences were slightly higher with respect to these parameters compared with the mothers' sequences. Both the mothers' and infants' NEF sequences were under positive selection pressure, as determined by a new method of Nielsen and Yang [Genetics 148:929-936;1998]. Based on genetic distance and phylogenetic parameters, the epidemiologically linked NEF sequences from mother-infant pairs were closer to each other compared with epidemiologically unlinked sequences from individuals. The functional domains essential for Nef activity, including membrane binding, CD4 and MHC-I downmodulation, T cell activation and interaction with factors of the cellular protein trafficking machinery, were conserved in most of the sequences from mother-infant pairs. The maintenance of intact NEF open reading frames with conserved functional domains and a low degree of genetic variability following vertical transmission supports the notion that NEF plays an important role in HIV-1 infection and replication in mothers and their perinatally infected infants.

Introduction: Increased abdominal gas content induces distension and can lead to abdominal discomfort and functional symptoms such as an altered intestinal motor activity. Still, the effects of abdominal bloating remain only partially described and understood. In order to study abdominal bloating and its effects on human physiology, methods are required that allow the non-invasive quantification of abdominal gas content. The aim of this study was to noninvasively determine changes in colonic gas content in health by means of Magnetic Resonance Imaging (MRI) after a one-week fiber supplementation. Methods: 15 healthy volunteers (7 female, 8 male, mean BMI 23.0) appeared each on two study days (day 1, day 8) for a 4 hours MRI session. During the 7 day treatment period, all subjects were asked to ingest 7 g of Normacol® (Norgine, Middlesex, UK) fiber supplement together with their breakfast. An additional dose of 7 g Normacol® was ingested on the evening prior to day 8. On both study days, subjects were asked to have a defined light breakfast 5 hours prior to study start. On day 8, subjects were asked to add 7 g Normacol® to their breakfast. At the beginning and at the end of the MRI session, high-resolution anatomic scans of the abdomen were acquired using a dedicated abdominal coil array (T2 weighted single-shot turbo spin-echo sequence; 1526/80; flip angle, 90°). Colonic structures were segmented in all volunteers. A pixel-by-pixel comparison of the image signal intensity with a predefined signal intensity threshold allowed labeling individual pixels as gas or solid. The predefined threshold was set to the background noise level (mean + 2 × stdev). Gas content inside the segmented areas was computed as gas/(gas+solid). Relative gas content was calculated as the average gas content on day 8 divided by the average gas content on day 1. A paired Wilcoxon signed rank test was performed to test the null hypothesis that gas content remained unchanged between study day 1 and study day 8. Results: Gas content was reduced in 12 out of 15 healthy volunteers after fiber supplementation. Gas content change was significant (p , 0.04). One prominent outlier (volunteer number 13) was detected, perhaps due to an improper intake of the prescribed fiber supplement. Overall, gas content on study day 8 was 73% ± 50% (mean ± stdev) relative to study day 1. Conclusion & Discussion: MRI has the sensitivity to noninvasively detect changes in colonic gas content after fiber supplementation in health. By providing the means for a noninvasive detection of colonic gas content in health, MRI shows potential for further studies on abdominal gas content in patient groups such as IBS.

Background HER2/neu is an oncogene that facilitates neoplastic transformation due to its ability to transduce growth signals in a ligand-independent manner, is over-expressed in 20-30% of human breast cancers correlating with aggressive disease and has been successfully targeted with trastuzumab (Herceptin®). Because trastuzumab alone achieves only a 15-30% response rate, it is now commonly combined with conventional chemotherapeutic drugs. While the combination of trastuzumab plus chemotherapy has greatly improved response rates and increased survival, these conventional chemotherapy drugs are frequently associated with gastrointestinal and cardiac toxicity, bone marrow and immune suppression. These drawbacks necessitate the development of new, less toxic drugs that can be combined with trastuzumab. Recently, we reported that orally administered alpha-tocopheryloxyacetic acid (α-TEA), a novel ether derivative of alpha-tocopherol, dramatically suppressed primary tumor growth and reduced the incidence of lung metastases both in a transplanted and a spontaneous mouse model of breast cancer without discernable toxicity. Methods In this study we examined the effect of α-TEA plus HER2/neu-specific antibody treatment on HER2/neu-expressing breast cancer cells in vitro and in a HER2/neu positive human xenograft tumor model in vivo. Results We show in vitro that α-TEA plus anti-HER2/neu antibody has an increased cytotoxic effect against murine mammary tumor cells and human breast cancer cells and that the anti-tumor effect of α-TEA is independent of HER2/neu status. More importantly, in a human breast cancer xenograft model, the combination of α-TEA plus trastuzumab resulted in faster tumor regression and more tumor-free animals than trastuzumab alone. Conclusion Due to the cancer cell selectivity of α-TEA, and because α-TEA kills both HER2/neu positive and HER2/neu negative breast cancer cells, it has the potential to be effective and less toxic than existing chemotherapeutic drugs when used in combination with HER2/neu antibody.