Phase I trial of anti-PSMA designer T cells in advanced prostate cancer

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Background: We created chimeric immunoglobulin-T cell receptors (IgTCR) specific for prostate specific membrane antigen (PSMA). When expressed in patient T cells, these “designer T cells” (dTc) specifically kill prostate cancer cells in vitro and in vivo in animal models, with 5/9 (55%) of xenografted mice experiencing complete remissions (Ma et al. Prostate 2004:61:12–25). A phase I clinical trial was approved by the FDA.

Methods: Patient T cells are retrovirally transduced and expanded ex vivo to span dose levels of 10^9 to 10^11 T cells. Patients undergo prior non-myeloablative (NMA) conditioning to create “hematologic space” into which designer T cells are infused for stable engraftment and prolonged in vivo efficacy. Patients are co-administered continuous infusion IL2. Outcomes include Phase Ia goals of safety and Phase Ib goals of establishing an optimal biologic dose in terms of designer T cell engraftment.

Results: Five patients have been treated, three at 10^9 and two at 10^10 cell dose levels. Excellent T cell modifications of 30%-60% were obtained. After NMA conditioning, T cells were infused. Stable engraftments of 1%-20% post-recovery at one month after T cell infusion, thus affirming one of the study end-points. Patients experienced neutropenic fever after conditioning, but no designer T cell-related toxicities. Two patients had partial responses with PSA reductions of 50 and 70% in the two months following treatment with projected benefits of 4 months gain of time to return to starting PSA levels. Results will be updated at the conference.

Conclusions: A new approach to adoptive immune therapy in metastatic prostate cancer has been devised with encouraging early results. Patients are being actively recruited. This clinical trial received partial funding from the US Army/DOD. Preclinical work was supported by the Prostate Cancer Foundation.

No significant financial relationships to disclose.

Rational design of alpha-helical antimicrobial peptide with Val and Arg residues

OBJECTIVE

The amphipathic alpha-helical peptide is an important class of antimicrobial peptides. In this study, a 16-residue-long peptide (VGR16) composed of 8 Val residues in the nonpolar face and 5 Arg residues in the polar face was designed based on the helical wheel projection to produce antimicrobial peptide with improved antibacterial activity accompanied by decreased toxicity.

METHODS

Antimicrobial activity and toxicity against red blood cells and mammalian cells were investigated to evaluate the biological function of the peptide. In addition, bactericidal kinetics was tested.

RESULTS

Antimicrobial assays revealed that the peptide VGR16 showed antimicrobial activity and their MICs against gram-negative and gram-positive bacteria ranged from 16 microg/ml to 64 microg/ml. VGR16 also exhibited rapid bactericidal action. It was surprisingly found that the peptide displayed no hemolytic activity even at a concentration of 256 microg/ml. Cell culture assays indicated that the peptide VGR16 had low cytotoxicity against mammalian cells.

CONCLUSION

The results showed that the peptide could be a likely candidate for future antimicrobial applications.

Dipeptidyl peptidase IV inhibitor sitagliptin reduces local inflammation in adipose tissue and in pancreatic islets of obese mice

Adipose tissue inflammation and reduced pancreatic β-cell function are key issues in the development of cardiovascular disease and progressive metabolic dysfunction in type 2 diabetes mellitus. The aim of this study was to determine the effect of the DPP IV inhibitor sitagliptin on adipose tissue and pancreatic islet inflammation in a diet-induced obesity model. C57Bl/6J mice were placed on a high-fat (60% kcal fat) diet for 12 wk, with or without sitagliptin (4 g/kg) as a food admix. Sitagliptin significantly reduced fasting blood glucose by 21% as well as insulin by ∼25%. Sitagliptin treatment reduced body weight without changes in overall body mass index or in the epididymal and retroperitoneal fat mass. However, sitagliptin treatment led to triple the number of small adipocytes despite reducing the number of the very large adipocytes. Sitagliptin significantly reduced inflammation in the adipose tissue and pancreatic islet. Macrophage infiltration in adipose tissue evaluated by immunostaining for Mac2 was reduced by sitagliptin (P < 0.01), as was the percentage of CD11b+/F4/80+ cells in the stromal vascular fraction (P < 0.02). Sitagliptin also reduced adipocyte mRNA expression of inflammatory genes, including IL-6, TNFα, IL-12(p35), and IL-12(p40), 2.5- to fivefold as well as 12-lipoxygenase protein expression. Pancreatic islets were isolated from animals after treatments. Sitagliptin significantly reduced mRNA expression of the following inflammatory cytokines: MCP-1 (3.3-fold), IL-6 (2-fold), IL-12(p40) (2.2-fold), IL-12(p35) (5-fold, P < 0.01), and IP-10 (2-fold). Collectively, the results indicate that sitagliptin has anti-inflammatory effects in adipose tissue and in pancreatic islets that accompany the insulinotropic effect.

High-energy x-ray backlighter spectrum measurements using calibrated image plates

The x-ray spectrum between 18 and 88 keV generated by a petawatt laser driven x-ray backlighter target was measured using a 12-channel differential filter pair spectrometer. The spectrometer consists of a series of filter pairs on a Ta mask coupled with an x-ray sensitive image plate. A calibration of Fuji™ MS and SR image plates was conducted using a tungsten anode x-ray source and the resulting calibration applied to the design of the Ross pair spectrometer. Additionally, the fade rate and resolution of the image plate system were measured for quantitative radiographic applications. The conversion efficiency of laser energy into silver Kα x rays from a petawatt laser target was measured using the differential filter pair spectrometer and compared to measurements using a single photon counting charge coupled device.

A new uterine compression suture for postpartum haemorrhage with atony

Postpartum haemorrhage (PPH) is a major cause of worldwide maternal mortality and is still associated with significant morbidity. After the B-Lynch suture was reported in 1997, several different uterine compression sutures were found to be successful in controlling PPH. In this paper, we describe another simple variation of the uterine compression suture technique, which was performed without an incision in the uterine wall, without entering the uterine cavity and without suturing the anterior and posterior walls of the uterus together, so minimising the trauma to the uterus. This new uterine compression suture is an effective and safe surgical treatment for PPH caused by atony. It has the potential to apply to intractable PPH after vaginal delivery.

Human lactoferrin stimulates skin keratinocyte function and wound re-epithelialization

BACKGROUND

Human lactoferrin (hLF), a member of the transferrin family, is known for its antimicrobial and anti-inflammatory effects. Recent studies on various nonskin cell lines indicate that hLF may have a stimulatory effect on cell proliferation.

OBJECTIVES

To study the potential role of hLF in wound re-epithelialization.

MATERIALS AND METHODS

The effects of hLF on cell growth, migration, attachment and survival were assessed, with a rice-derived recombinant hLF (holo-rhLF), using proliferation analysis, scratch migration assay, calcein-AM/propidium iodide staining and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL) method, respectively. The mechanisms of hLF on cell proliferation and migration were explored using specific pathway inhibitors. The involvement of lactoferrin receptor low-density lipoprotein receptor-related protein 1 (LRP1) was examined with RNA interference technique. An in vivo swine second-degree burn wound model was also used to assess wound re-epithelialization.

RESULTS

Studies revealed that holo-rhLF significantly stimulated keratinocyte proliferation which could be blocked by mitogen-activated protein kinase (MAPK) kinase 1 inhibitor. Holo-rhLF also showed strong promoting effects on keratinocyte migration, which could be blocked by either inhibition of the MAPK, Src and Rho/ROCK pathways, or downregulation of the LRP1 receptor. With cells under starving or 12-O-tetradecanoylphorbol-13-acetate exposure, the addition of holo-rhLF was found greatly to increase cell viability and inhibit cell apoptosis. Additionally, holo-rhLF significantly increased the rate of wound re-epithelialization in swine second-degree burn wounds.

CONCLUSIONS

Our studies demonstrate the direct effects of holo-rhLF on wound re-epithelialization including the enhancement of keratinocyte proliferation and migration as well as the protection of cells from apoptosis. The data strongly indicate its potential therapeutic applications in wound healing.

c-Abl and Arg tyrosine kinases regulate lysosomal degradation of the oncoprotein Galectin-3

Galectin-3 (Gal3) has important roles in tumor transformation and metastasis. This study shows that c-Abl and Abl-related gene (Arg) associate with and phosphorylate Gal3. The SH (Src homology)3 domains of c-Abl/Arg bind to a P(80)GPPSGP motif of Gal3, and Tyr79 and Tyr118 are the major tyrosine phosphorylation sites. A consequence of this interaction and phosphorylation is the significant impairment of chaperone-mediated autophagy of Gal3. Cells expressing Gal3 and treated with the c-Abl/Arg inhibitor STI571, Gal3-depleted cells, and Gal3-depleted cells expressing Gal3 phosphorylation mutants all display an increased sensitivity to apoptosis-inducing agents. In addition, tumor cells expressing the phosphorylation mutants show impaired tumorigenicity. These results partially explain the antiapoptotic effect of Abl and Arg. As tumors frequently overexpress Gal3, a c-Abl/Arg-specific inhibitor may potentially be applied along with other antitumor drugs to target the lysosomal degradation of Gal3 in tumor therapy.

Efficacy and safety of pegylated interferon alpha-2a therapy for chronic hepatitis C in HIV-infected patients with haemophilia

The objective of this study was to evaluate the efficacy and safety of pegylated interferon (PEG-IFN) alpha-2a monotherapy in a cohort of Chinese haemophilic patients co-infected with human immunodeficiency virus (HIV)/hepatitis C virus (HCV) and undergoing highly active antiretroviral drugs therapy. Twenty-two (n = 22) patients with CD4 lymphocyte counts over 200 cells microL(-1) were treated with 180 microg of PEG-IFN alpha-2a subcutaneously once in a week for 48 weeks. HCV load (HCV RNA), HIV load (HIV RNA) and CD4 lymphocyte counts were measured at baseline and 4, 12, 24, 48 and 72 weeks after initiation of anti-HCV therapy. Efficacy and safety were analysed according to baseline CD4 status (> or =350 cells microL(-1)). Significant HCV-RNA decreases (>1 log(10) copies mL(-1)) were observed through week 72 after PEG-INF alpha-2a monotherapy across both CD4 strata. CD4 status was not associated with treatment outcomes as evaluated using rapid viral response rate (P = 0.655), early viral response rate (P = 0.387), end-of-treatment viral response rate (P = 1.000) or sustained viral response rate (SVR, P = 0.674). A sustained virological response was achieved in nine patients (41%), five with genotype 2a (83%) and four with genotype 1b (25%, P = 0.023). SVR was HCV genotype dependent. Eleven patients required a dose reduction in PEG-IFN alpha-2a. PEG-IFN alpha-2a monotherapy could be considered as a safe and effective option for the treatment of HCV infection in HIV patients with haemophilia, particularly in resource-limited settings. While higher CD4 lymphocyte counts resulted in greater HCV-RNA reduction, HCV genotype was a predictor for sustained virological response.

Phase I trial of advanced generation anti-CEA designer T cells in gastrointestinal and breast cancers

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Background: We created “designer T cells” by retroviral gene therapy to express chimeric immunoglobulin-T cell receptors (IgTCR) with specificity for carcinoembryonic antigen (CEA). Our previous Phase I trial with 1st generation (1st gen) designer T cells was well tolerated with proof-of-principle “biologic responses”, but of limited duration. Lab correlates showed modified T cells repeatedly kill tumor targets over 4–7 days but then undergo activation-induced cell death (AICD). We created 2nd gen designer T cells that incorporate CD28 co-stimulation into the IgTCR (IgCD28TCR), suppressing AICD and promoting T cell proliferation on tumor contact with superior tumor responses in vivo (Emtage et al. Clin Cancer Res 2008;14:8112). A Phase I clinical trial was approved under FDA BB-IND 10791. Methods: Patient T cells are modified ex vivo, expanded and then administered in a Phase Ia dose escalation, spanning doses of 10^9 to 10^11 cells. Patients are monitored for safety, pharmacokinetics and response. Results: To date, three subjects enrolled with doses prepared and two were treated. T cells were transduced with equal modification of CD4 helper and CD8 cytotoxic T cells and good ex vivo expansions of 30-fold or more. Cells were infused over 15–30 minutes. Blood clearance was rapid. Dosing was without toxicity but also without responses at this lowest T cell dose level. Results will be updated to include new patients at conference time. Conclusions: The safety of 2nd generation designer T cells is supported in two patients at the lowest T cell dose level. Higher planned doses are 10- to 100-fold more T cells, to be observed for toxicity and where responses may begin to be observed. Funding is from the Office of Orphan Products Development of the FDA.

No significant financial relationships to disclose.

Phase I trial of anti-PSMA designer T-cell autografting in prostate cancer

e16132

Background: We created chimeric immunoglobulin-T cell receptors (IgTCR) specific for prostate specific membrane antigen (PSMA). When expressed in patient T cells, these “designer T cells” specifically kill prostate cancer cells in vitro and in vivo in animal models, with 5/9 (55%) of xenografted mice experiencing complete remissions (Ma et al. Prostate 2004:61:12–25). A Phase I clinical trial was approved by the FDA in metastatic prostate cancers. Methods: Patient T cells are retrovirally transduced and expanded ex vivo to span dose levels of 10^9 to 10^11 T cells. Adapting methods of Dudley, Rosenberg and colleagues, patients undergo prior non-myeloablative (NMA) conditioning to create a “hematologic space” into which the infused designer T cells will stably engraft for prolonged in vivo efficacy. Patients are co-administered continuous infusion IL2. Outcomes will include Phase Ia goals of safety and toxicity and Phase Ib goals of establishing an optimal biologic dose in terms of designer T cell engraftment and tumor response. Results: For the first two patients, excellent T cell modifications of 50–60% were obtained. After NMA conditioning, T cells were infused and stable engraftments of 1–5% were observed post recovery, even at this lowest 10^9 T cell dose level, thus affirming one of the study end-points. The patients had PSA reductions of 50 and 70% in the two months following treatment. Patients experienced neutropenia and lymphopenia after conditioning, but no designer T cell-related toxicities. Results with additional patients will be described in terms of safety, engraftment efficiency and tumor responses. Conclusions: A new approach to adoptive immune therapy in metastatic prostate cancer has been devised. This clinical trial is funded by the US Army/DOD.

No significant financial relationships to disclose.

Blockade of SDF-1/CXCR4 signalling inhibits pancreatic cancer progression in vitro via inactivation of canonical Wnt pathway

Extra-pancreatic metastasis is a difficult problem for surgical intervention in pancreatic cancer. CXC chemokine receptor 4 (CXCR4) was considered to have an important role in this process. We hypothesized it may contribute to the pancreatic cancer progression through influencing canonical Wnt pathway. The purpose of this study was to examine the functional role of CXCR4 in the progression of pancreatic cancers and explore the possible mechanism. To this end, the relation between CXCR4 and clinical characteristics was analysed. shRNA against CXCR4 was applied to disrupt the SDF-1/CXCR4 signal transduction pathways in pancreatic cancer cell lines. Our results showed that overall survival in the case of patients positive for CXCR4 expression was significantly lower than that in the case of patients negative for CXCR4 expression. Notably, in vitro studies we observed that the abrogation of CXCR4 could obviously influence the pancreatic cancer cell phenotype including cell proliferation, colony formation, cell invasion and also inhibit the TOPflash activity. In addition, Wnt target genes and mesenchymal markers such as Vimentin and Slug were also inhibited in CXCR4 knockdown cells. Collectively, these data reported here demonstrate CXCR4 could modulate the canonical Wnt pathway and perhaps be a promising therapeutic target for pancreatic cancer progression.

Temperature dependences of mechanisms responsible for the water-vapor continuum absorption. I. Far wings of allowed lines

It is well known that the water-vapor continuum plays an important role in the radiative balance in the Earth's atmosphere. This was first discovered by Elsasser almost 70 years ago, and since that time there has been a large body of work, both experimental and theoretical, on this topic. It has been experimentally shown that for ambient atmospheric conditions, the continuum absorption scales quadratically with the H(2)O number density and has a strong, negative temperature dependence (T dependence). Over the years, there have been three different theoretical mechanisms postulated: Far wings of allowed transitions, water dimers, and collision-induced absorption. Despite the improvements in experimental data, at present there is no consensus on which mechanism is primarily responsible for the absorption. The first mechanism proposed was the accumulation of the far-wing absorption of the strong allowed transitions. Later, absorption by water dimers was proposed and this mechanism provides a qualitative explanation for the strong, negative T dependence. Recently, some atmospheric modelers have proposed that collision-induced absorption is one of the major contributors. However, based on improvements in the theoretical calculation of accurate far-wing line shapes, ab initio dimer calculations, and theoretical collision-induced absorptions, it is now generally accepted that the dominant mechanism for the absorption in the infrared (IR) windows is that due to the far wings. Whether this is true for other spectral regions is not presently established. Although all these three mechanisms have a negative T dependence, their T dependences will be characterized by individual features. To analyze the characteristics of the latter will enable one to assess their roles with more certainty. In this paper, we present a detailed study of the T dependence of the far-wing absorption mechanism. We will then compare our theoretical calculations with the most recent and accurate experimental data in the IR windows. The results of our calculations are found to agree very well with measurements in the 800-1200 cm(-1) region. We conclude from this work that the T dependence in the IR window region predicted by the far-wing theory is negative and moderately strong. Its pattern is not simple and it could vary significantly as the frequency of interest varies.

Pharmacological targeting of C5a receptors during organ preservation improves kidney graft survival

Cadaveric renal transplants suffer frequently from delayed graft function, which is associated with increased risk for long-term graft survival loss. One-third of kidney grafts that are stored in current organ preservation solutions experience delayed graft function, demonstrating the urgent need for improvement. Although ischaemic graft injury is complex in nature, complement activation is considered important to the process. Here we show that pharmacological targeting of the complement 5a receptor (C5aR) during cold ischaemia has a protective effect on early kidney graft survival, inflammation and apoptosis in a mouse model of syngeneic kidney transplantation. Graft survival of kidneys that were stored in University of Wisconsin solution in the presence of a C5aR antagonist increased from 29% to 57%. Increased graft survival was associated with less tubular damage and apoptosis, protection from sustained C5aR expression and decreased production of tumour necrosis factor-alpha and macrophage inflammatory protein-2. In a translational approach, we determined C5aR expression in paediatric living-related and cadaveric allografts. C5aR expression was significantly higher in all compartments of kidneys from cadaveric compared with kidneys from living-related donors. C5aR expression in cadaveric kidneys correlated positively with cold ischaemia time, renal dysfunction and the frequency of apoptotic tubular cells, suggesting a novel role for C5a in delayed graft function pathogenesis. Supplementing organ preservation solutions with C5aR inhibitors may improve early graft function following cadaveric kidney transplantation.

Hydraulic lift by canola plants aids P and K uptake from dry topsoil

The role of hydraulic lift in nutrient uptake from dry topsoil is unclear. Vertically-split root systems were used to measure hydraulic lift and phosphorus (P) and potassium (K) uptake at the rosette and flowering stages of two canola (Brassica napus L.) cultivars (Trigold and Boomer with small and large root systems, respectively) grown in soil low in P and K. Rubidium (Rb) was used as a tracer to examine K uptake from K fertiliser banded in dry topsoil. During vegetative growth, statistically significant hydraulic lift was measured, irrespective of cultivar root size or a specific nutrient (P or K) placed in the topsoil. The Rb tracer revealed significant amounts of K were absorbed from the dry soil, but at rates five-fold lower than from the moist soil. The water lifted could not prevent cessation of P uptake by Boomer and a reduction in P uptake by Trigold. During mid to late flowering, ion uptake from the dry topsoil was impeded despite the continuation of hydraulic lift up to 28 days after the topsoil was dried. Minimal fine root growth following topsoil drying (and reduction in fine root biomass in some treatments) appeared to be the primary cause of impeded nutrient uptake.