Clinical Trials For Cancer Therapy Research Articles

Human epidermal growth factor antagonists and cardiotoxicity-A short review of the problem and preventative measures.

The Human Epidermal growth factor Receptor 2 (HER2) is a potent mediator of cellular growth and proliferation. It plays an important role in cardiac development and maintaining the physiologic function of an adult heart. Amplification of the HER2 gene, and the corresponding overexpression of the HER2 receptor, occurs in roughly 20% of breast tumors and is associated with a poor outcome. Molecular targeting of the HER2 receptor with the humanized monoclonal antibody, Trastuzumab has improved disease-free and overall survival in patients with both metastatic and early HER2-positive breast cancer. Although trastuzumab is devoid of the classical toxicities associated with chemotherapy, one of the major concerns noted is the occurrence of symptomatic and asymptomatic cardiotoxicity (decline in left-ventricular-ejection-fraction (LVEF). Additionally, newer HER2 therapies such as Lapatinib, Pertuzumab and Ado-trastuzumab (TDM1) are either approved or are being evaluated in clinical trials for cancer therapy. Targeted therapies against HER2 have led to revolutionary strides in breast cancer research and treatment. With the concern of cardiotoxicity caused by these agents, new treatment strategies for preventing cardiac side effects need to be developed. In this review, we discuss the proposed mechanisms of HER 2 antagonist-induced cardiotoxicity and the ways to prevent it.

Longitudinal adverse event assessment in oncology clinical trials: the Toxicity over Time (ToxT) analysis of Alliance trials NCCTG N9741 and 979254

BackgroundTraditional methods of reporting adverse events (AEs) in clinical trials are inadequate for modern oncology therapies with chronic administration. Conventional analysis and display of maximum grade AEs do not capture toxicity profiles that evolve over time or longer lasting, lower grade toxicity as does this longitudinal Toxicity over Time (ToxT) approach.MethodsGraphical and analytical routines were compiled into an automated and standardized format to comprehensively analyze AEs. Plots visualizing summary statistics or individual patient data over discreet time points were combined with statistical methodology including longitudinal techniques (repeated measures models that describe the changes in AEs over each time period; time-to-event analyses of first, worst, or high grade; and area under the curve (AUC) analyses summarizing AE profiles over the entire study). The analytic capability of ToxT was demonstrated using two completed North Central Cancer Treatment Group (NCCTG)/Alliance clinical trials in cancer therapy (N9741, NCT00003594) and symptom control (979254).FindingsBar charts and stream plots showed higher incidences of dry mouth occurring late in 979254 for venlafaxine compared to placebo (week 1 [baseline]: 13% vs 22%, p=0.20; week 5: 49% vs 2%, p<0.0001) and increased nausea early for IROX vs FOLFOX in N9741 (cycle 1: mean grade 1.1 versus 0.6, p<0.0001). Event charts visually depicted earlier occurrences of higher diarrhea grades for IROX patients and the AUC analysis indicated a higher magnitude of diarrhea experience over time in IROX compared to FOLFOX (4.2 versus 2.9, p<0.0001).InterpretationThe ToxT analytic approach incorporates the dimension of time and offers a more comprehensive depiction of toxicity than current methods. With new, continuously administered targeted agents and maintenance regimens, these improved longitudinal analyses are directly relevant to patients and are imperative in oncology clinical trials.FundingUS National Cancer Institute Alliance NCORP Research Base Grant (UG1CA 189823) and Mayo Comprehensive Cancer center Grant–Biostatistics (P30CA 15083).

Pharmacological Inhibition of Hsp90 Destabilizes the Histone Methyltransferase Ezh2 in Alloreactive T Cells and Reduces Graft-Versus-Host Disease While Retaining Anti-Leukemic Effects in Mice

Graft-versus-host disease (GVHD) remains a major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT). GVHD involves complex interactions of immune cells, induction of host-reactive donor effector T cells, and donor T cell-mediated injury to normal tissues. Epigenetic changes have been implicated in T cell-mediated GVHD. We previously described that genetic deletion of Ezh2, which catalyzes trimethylation of histone H3 at lysine 27 (H3K27me3), reduced GVHD in mice but preserved graft-versus-leukemia (GVL) responses. Several selective inhibitors of Ezh2 have been recently discovered (e.g. GSK126, UNC1999 and EPZ6438), which specifically reduce the levels of H3K27me3 but not EZH2 protein. Unexpectedly, our preliminary studies showed that administration of GSK126 failed to prevent GVHD in mice. This stands in contrast to our findings that genetic deletion of T cell Ezh2 leads to GVHD inhibition, and suggest that Ezh2 may regulate GVHD through a mechanism independent of H3K27me3. Identifying an optimal method to target T cell Ezh2 for controlling GVHD remains an unmet need.Using experimental mouse models, we demonstrate that functional heat shock protein (Hsp)90 is critical for maintaining Ezh2 protein stability and function in activated T cells. Pharmacological inhibition of Hsp90 destablizes Ezh2 protein in alloreactive T cells, reduces GVHD but preserves GVL effects in mice. To determinethe molecule(s) that is critical for maintaining Ezh2 protein stablility in T cells, we performed mass spectrum (MS) analysis and identified 25 Ezh2-interacting proteins that showed higher intensities than others in T cell receptor (TCR)-activated CD8+ T cells. Among them, we found a group of proteins associated with protein folding and degradation, including Hsp90. Hsp90 is a molecular chaperone required for the stability and function of several key signaling intermediates (e.g., AKT, Raf1 and ERK1/2). Using reciprocal co-immunoprecipitation assay, we confirmed that Ezh2 and Hsp90 directly interacted with each other in TCR-activated CD8+ T cells. Pharmacological inhibition of Hsp90 using its specific inhibitor AUY922, which is currently in phase II clinical trials for cancer therapy, effectively reduced Ezh2 protein without decreasing H3K27me3 24 hours after treatment. This effect was accompanied by decreased proliferation and survival of TCR-activated T cells in vitro. Retroviral overexpression of Ezh2 in T cells markedly improved their proliferation in the presence of AUY922, suggesting that reducing Ezh2 by Hsp90 inhibition is an important mechanism that reduces proliferation and survival of activated CD8+ T cells. Building on these observations, we examined the impact of inhibiting Hsp90 on GVHD by administering AUY922 to B6 mice receiving MHC-identical minor histocompatibility antigen-mismatched C3H.SW mouse CD8+ T cells and T cell-depleted bone marrow (BM). While about 80% of control B6 recipients died from severe GVHD, 80% of AUY922-treated B6 recipients survived without clinical signs of severe GVHD by 84 days after transplantation. In vivo AUY922 administration reduced the survival and expansion of alloreactive T cells, and decreased the fequency of alloreactive T effector cells producing IFN-g and TNF-a. To rule out the model-specific effect of AUY922, we used a haplo-identical B6 into BDF1 mouse model of GVHD. Using CFSE-labeled donor T cells, we first validated that in vivo administration of AUY922 to unirradiated BDF1 mice receiving parent B6 T cells selectively reduced the expansion of alloantigen-reactive donor T cells, but did not impair the expansion and survival of donor T cells that did not respond to alloantigens. In lethally irradiated BDF1 mice receiving B6 T cells and BM, AUY922 administration reduces lethal GVHD, with approximately 50% of them surviving long-time. Importantly, AUY922 treatment preserved GVL activity of donor T cells, leading to significantly improved survival of BDF1 recipients challenged with A20 leukemic cells (Fig.1).Taken together, our findings identified a previously unrecognized molecular mechanism by which Ezh2 and Hsp90 are integrated to regulate alloreactive T cell responses and GVHD. Targeting the Ezh2-Hsp90 complex using AUY922 represents a novel and clinically relevant approach to reduce GVHD while preserving GVL effects, thereby improving the efficacy of allo-HSCT. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Gene therapy for cancer: regulatory considerations for approval.

The rapidly changing field of gene therapy promises a number of innovative treatments for cancer patients. Advances in genetic modification of cancer and immune cells and the use of oncolytic viruses and bacteria have led to numerous clinical trials for cancer therapy, with several progressing to late-stage product development. At the time of this writing, no gene therapy product has been approved by the United States Food and Drug Administration (FDA). Some of the key scientific and regulatory issues include understanding of gene transfer vector biology, safety of vectors in vitro and in animal models, optimum gene transfer, long-term persistence or integration in the host, shedding of a virus and ability to maintain transgene expression in vivo for a desired period of time. Because of the biological complexity of these products, the FDA encourages a flexible, data-driven approach for preclinical safety testing programs. The clinical trial design should be based on the unique features of gene therapy products, and should ensure the safety of enrolled subjects. This article focuses on regulatory considerations for gene therapy product development and also discusses guidance documents that have been published by the FDA.

Sulforaphane, a naturally occurring isothiocyanate, exhibits anti-inflammatory effects by targeting GSK3β/Nrf-2 and NF-κB pathways in T cells

A potent Nrf-2 activator sulforaphane (SF), which is currently under clinical trials for cancer therapy, was employed to elucidate the role of Keap1/Nrf-2/ARE signalling pathway in T-cell responses. SF suppressed mitogen induced T-cell and B-cell proliferation. It also inhibited mitogen induced upregulation of T-cell (CD25 and CD69) and B-cell (CD80 and CD86) activation markers and suppressed secretion of cytokines (IL-2, IL-4, IL-6 and IFN-γ). SF induced oxidative stress and its anti-inflammatory effects were abrogated by thiol antioxidants. SF activated PI3K/AKT, leading to phosphorylation mediated suppression of GSK3β resulting in Nrf-2 activation. We also show for the first time that SF can prevent direct interaction between NF-κB and its consensus sequence by modulating thiol groups. It also suppressed homeostatic proliferation of T-cells and suppressed lipopolysaccharide induced pro-inflammatory mediators in macrophages. Our study shows that the potent anti-inflammatory effects of SF are mediated via modulation of PI3K/AKT/GSK3β/Nrf-2 and NF-κB pathway in T-cells.

Epigenetic Therapy for Solid Tumors: Highlighting the Impact of Tumor Hypoxia.

In the last few decades, epigenetics has emerged as an exciting new field in development and disease, with a more recent focus towards cancer. Epigenetics has classically referred to heritable patterns of gene expression, primarily mediated through DNA methylation patterns. More recently, it has come to include the reversible chemical modification of histones and DNA that dictate gene expression patterns. Both the epigenetic up-regulation of oncogenes and downregulation of tumor suppressors have been shown to drive tumor development. Current clinical trials for cancer therapy include pharmacological inhibition of DNA methylation and histone deacetylation, with the aim of reversing these cancer-promoting epigenetic changes. However, the DNA methyltransferase and histone deacetylase inhibitors have met with less than promising results in the treatment of solid tumors. Regions of hypoxia are a common occurrence in solid tumors. Tumor hypoxia is associated with increased aggressiveness and therapy resistance, and importantly, hypoxic tumor cells have a distinct epigenetic profile. In this review, we provide a summary of the recent clinical trials using epigenetic drugs in solid tumors, discuss the hypoxia-induced epigenetic changes and highlight the importance of testing the epigenetic drugs for efficacy against the most aggressive hypoxic fraction of the tumor in future preclinical testing.

Abstract A56: A dual PI3K-mTOR inhibitor induced cardiac hypertrophy in mice: Role of the insulin signaling

Abstract Studies from us and others showed that mice with cardiomyocyte-specific overexpression of a dominant negative PI3Kp110α had smaller hearts but maintained normal cardiac function. Yet, these mice developed systolic heart failure in the presence of cardiac stress, such as chemotherapy drug doxorubicin and aortic stenosis. Currently, drugs targeting the PI3K pathway are being tested in clinical trials for cancer therapy. Therefore, it is important to assess the cardiac effects of pharmacological inhibition of this pathway. Here, we report that a dual PI3K-mTOR inhibitor, BEZ235 (BEZ), induced cardiac hypertrophy and subsequent heart failure in mice when it was used alone or in combination with doxorubicin. This effect of BEZ was associated with increased hepatic gluconeogenesis, hyperglycemia, hyperinsulinemia and increased activation of the IGFR/insulin receptor (IR) in the heart. In isolated cardiomyocyte culture, BEZ induced feedback activation of IGFR/IR, but this effect was negligible compared to the IGFR/IR activation in the presence of insulin. Injections of insulin in mice lowered blood glucose, improved glucose and pyruvate tolerance but further increased the activation of IGFR/IR in the heart and aggravated BEZ-induced cardiac dysfunction; whereas OSI-906, an IGFR/IR inhibitor, alleviated this cardiac dysfunction. In addition, low dose Metformin significantly prolonged survival and improved cardiac function in BEZ-treated mice. Taken together, these results identified hyperinsulinemia, a systematic effect of the drug, as one of the mechanisms of BEZ-induced cardiac hypertrophy, arguing animal studies are indispensable for evaluating drug toxicity. They also suggest that Metformin but not insulin should be considered for controlling hyperglycemia and preventing the cardiac side effects that may be caused by PI3K pathway inhibitors in clinic. Citation Format: Jillian Onufrak, Yongayo Yang, Juyong Lee, John Fuseler, Maoyun Sun, Sharath Sasi, J. Tyson McDonald, Lynn Hlatky, Robert L. Price, Joseph Carrozza, David Goukassian, Thomas K. Borg, James P. Morgan, Xinhua Yan. A dual PI3K-mTOR inhibitor induced cardiac hypertrophy in mice: Role of the insulin signaling. [abstract]. In: Proceedings of the AACR Special Conference: Targeting the PI3K-mTOR Network in Cancer; Sep 14-17, 2014; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(7 Suppl):Abstract nr A56.

Sirtuins Function as the Modulators in Aging-related Diseases in Common or Respectively.

Sirtuins Function as the Modulators in Aging-related Diseases in Common or Respectively.

Gambogic acid induces apoptosis in diffuse large B-cell lymphoma cells via inducing proteasome inhibition.

Resistance to chemotherapy is a great challenge to improving the survival of patients with diffuse large B-cell lymphoma (DLBCL), especially those with activated B-cell-like DLBCL (ABC-DLBCL). Therefore it is urgent to search for novel agents for the treatment of DLBCL. Gambogic acid (GA), a small molecule derived from Chinese herb gamboges, has been approved for Phase II clinical trial for cancer therapy by Chinese FDA. In the present study, we investigated the effect of GA on cell survival and apoptosis in DLBCL cells including both GCB- and ABC-DLBCL cells. We found that GA induced growth inhibition and apoptosis of both GCB- and ABC-DLBCL cells in vitro and in vivo, which is associated with proteasome malfunction. These findings provide significant pre-clinical evidence for potential usage of GA in DLBCL therapy particularly in ABC-DLBCL treatment.

Something in the Air: Hyperoxic Conditioning of the Tumor Microenvironment for Enhanced Immunotherapy

Recent clinical trials in cancer therapy have demonstrated unprecedented responses through blockade of CTLA-4 and PD-1 immune checkpoint pathways. In a provocative recent paper in Science Translational Medicine, Hatfield and colleagues demonstrate the ability of supplemental oxygen to act as a novel immune checkpoint inhibitor by disrupting the hypoxia-adenosine-A2aR pathway.

Nickel-backed Bi targets for the production of 211At

To support clinical trials for cancer therapy with radiotherapeutic isotopes in the United States reliable sources of adequate quantities of several such isotopes, especially of alpha emitters such as 211At, are a high priority of the DOE Isotopes Program. We have recently tested an alternative reaction, 209Bi(6Li, 4n)211Rn (which decays to 211At) with a 42 MeV 6Li beam from the ATLAS superconducting linac. This latter reaction has the advantage that radon gas is easy to extract and the 14.6-h 211Rn half-life allows more time for transport to the therapy facility. The Bi targets were prepared on a Ni backing as these elements have similar coefficients of thermal expansion, minimizing the chance of target delamination. Helium gas flowed between a thin window and the target to transport the 211Rn it to a charcoal trap. The goal was to develop a method for continuous production and collection of 211At that does not require dissolving the target following each production run. Details of the Bi target production and performance is presented as well as some initial experimental results.

The RAF-MEK-ERK pathway: targeting ERK to overcome obstacles to effective cancer therapy.

Currently, dozens of BRAF inhibitors and MEK inhibitors targeting RAF-MEK-ERK pathway have been introduced into clinical trials for cancer therapy. However, after 6-8 months of initial response, acquired drug resistance among the majority of those treated patients sharply diminished their clinical efficacy. Important mechanisms responsible for acquired resistance of BRAF inhibitors and MEK inhibitors have been elucidated. Continually, ERK1/2 locates in the critical position and features unique characteristics, such as activating hundreds of substrates, participating in feedback regulation, being catalyzed by MEK specifically and no acquired resistant mutation. Taking in account the inspiring outcomes of ERK inhibitors in preclinical research, ERK1/2 might be the optimal target to overcome acquired drug resistance in RAF-MEK-ERK pathway.

Onconase induces autophagy sensitizing pancreatic cancer cells to gemcitabine and activates Akt/mTOR pathway in a ROS-dependent manner

Onconase® (ONC) is a member of the RNase super-family that is secreted in oocytes and early embryos of Rana pipiens. Over the last years, research interest about this small and basic frog RNase, also called ranpirnase, constantly increased because of its high cytotoxicity and anticancer properties. Onconase is currently used in clinical trials for cancer therapy; however, the precise mechanisms determining cytotoxicity in cancer cells have not yet been fully investigated. In the present manuscript, we evaluate the antitumoral property of onconase in pancreatic adenocarcinoma cells and in non-tumorigenic cells as a control. We demonstrate that ONC stimulates a strong antiproliferative and proapoptotic effect in cancer cells by reporting for the first time that ONC triggers Beclin1-mediated autophagic cancer cell death. In addition, ONC inhibits the expression of mitochondrial uncoupling protein 2 (UCP2) and of manganese-dependent superoxide dismutase (MnSOD) triggering mitochondrial superoxide ion production. ONC-induced reactive oxygen species (ROS) are responsible for Akt/mTOR pathway stimulation determining the sensitivity of cancer cells to mTOR inhibitors and lessening autophagic stimulation. This indicates ROS/Akt/mTOR axis as a strategy adopted by cancer cells to reduce ONC-mediated cytotoxic autophagy stimulation. In addition, we demonstrate that ONC can sensitize pancreatic cancer cells to the standard chemotherapeutic agent gemcitabine allowing a reduction of drug concentration when used in combination settings, thus suggesting a lowering of chemotherapy-related side effects. Altogether, our results shed more light on the mechanisms lying at the basis of ONC antiproliferative effect in cancer cells and support its potential use to develop new anticancer strategies.

Identification of diphtheria toxin R domain mutants with enhanced inhibitory activity against HB-EGF.

Heparin-binding epidermal growth factor-like growth factor (HB-EGF), a ligand of EGF receptor, is involved in the growth and malignant progression of cancers. Cross-reacting material 197, CRM197, a non-toxic mutant of diphtheria toxin (DT), specifically binds to the EGF-like domain of HB-EGF and inhibits its mitogenic activity, thus CRM197 is currently under evaluation in clinical trials for cancer therapy. To develop more potent DT mutants than CRM197, we screened various mutant proteins of R domain of DT, the binding site for HB-EGF. A variety of R-domain mutant proteins fused with maltose-binding protein were produced and their inhibitory activity was evaluated in vitro. We found four R domain mutants that showed much higher inhibitory activity against HB-EGF than wild-type (WT) R domain. These R domain mutants suppressed HB-EGF-dependent cell proliferation more effectively than WT R domain. Surface plasmon resonance revealed their higher affinity to HB-EGF than WT R domain. CRM197(R460H) carrying the newly identified mutation showed increased cell proliferation inhibitory activity and affinity to HB-EGF. These results suggest that CRM197(R460H) or other recombinant proteins carrying newly identified mutation(s) in the R domain are potential therapeutics targeting HB-EGF.

Neuropilin-1 expression is induced on tolerant self-reactive CD8+ T cells but is dispensable for the tolerant phenotype.

Establishing peripheral CD8+ T cell tolerance is vital to avoid immune mediated destruction of healthy self-tissues. However, it also poses a major impediment to tumor immunity since tumors are derived from self-tissue and often induce T cell tolerance and dysfunction. Thus, understanding the mechanisms that regulate T cell tolerance versus immunity has important implications for human health. Signals received from the tissue environment largely dictate whether responding T cells become activated or tolerant. For example, induced expression and subsequent ligation of negative regulatory receptors on the surface of self-reactive CD8+ T cells are integral in the induction of tolerance. We utilized a murine model of T cell tolerance to more completely define the molecules involved in this process. We discovered that, in addition to other known regulatory receptors, tolerant self-reactive CD8+ T cells distinctly expressed the surface receptor neuropilin-1 (Nrp1). Nrp1 was highly induced in response to self-antigen, but only modestly when the same antigen was encountered under immune conditions, suggesting a possible mechanistic link to T cell tolerance. We also observed a similar Nrp1 expression profile on human tumor infiltrating CD4+ and CD8+ T cells. Despite high expression on tolerant CD8+ T cells, our studies revealed that Nrp1 had no detectable role in the tolerant phenotype. Specifically, Nrp1-deficient T cells displayed the same functional defects as wild-type self-reactive T cells, lacking in vivo cytolytic potential, IFNγ production, and antitumor responses. While reporting mostly negative data, our findings have therapeutic implications, as Nrp1 is now being targeted for human cancer therapy in clinical trials, but the precise molecular pathways and immune cells being engaged during treatment remain incompletely defined.

Anti-HER2 cancer therapy and cardiotoxicity.

A significant milestone in the treatment of breast cancer is the identification of the HER2 receptor as a drug target for cancer therapies. Trastuzumab (Herceptin), a monoclonal antibody that blocks the HER2 receptor, is among the first of such drugs approved by the US Food and Drug Administration for targeted cancer therapy. Clinical studies have shown that Trastuzumab significantly improves the overall survival of breast cancer patients. However, an unforeseen significant side-effect of cardiotoxicity manifested as left ventricular dysfunction and heart failure. Concurrent studies have demonstrated the essential role of the HER2 receptor in cardiac development and maintaining the physiological function of an adult heart. The HER2 receptor, therefore, has become a critical link between the oncology and cardiology fields. In addition to Trastuzumab, new drugs targeting the HER2 receptor, such as Lapatinib, Pertuzumab and Afatinib, are either approved or being evaluated in clinical trials for cancer therapy. With the concern of cardiotoxicity caused by HER2 inhibition, it becomes clear that new therapeutic strategies for preventing such cardiac side effects need to be developed. It is the intent of this paper to review the potential cardiac impact of anti-HER2 cancer therapy.

The ethics of clinical trials for cancer therapy.

Cancer clinical trials are intended to evaluate novel interventions and to improve outcomes. Such research depends on the participation of patients seeking the best options for care. The design, conduct, and analysis of trials must therefore be grounded in an ethical framework that respects and protects the interests of clinical trial participants.

SNX-25a, a novel Hsp90 inhibitor, inhibited human cancer growth more potently than 17-AAG

17-Allylamino-17-demethoxygeldanamycin (17-AAG), a typical Hsp90 inhibitor derived from geldanamycin (GA), has entered Phase III clinical trials for cancer therapy. However, it has several significant limitations such as poor solubility, limited bioavailability and unacceptable hepatotoxicity. In this study, the anticancer activity and mechanism of SNX-25a, a novel Hsp90 inhibitor, was investigated comparing with that of 17-AAG. We showed that SNX-25a triggered growth inhibition more sensitively than 17-AAG against many human cancer cells, including K562, SW-620, A375, Hep-2, MCF-7, HepG2, HeLa, and A549 cell lines, especially at low concentrations (<1μM). It showed low cytotoxicity in L-02, HDF and MRC5 normal human cells. Compared with 17-AAG, SNX-25a was more potent in arresting the cell cycle at G2 phase, and displayed more potent effects on human cancer cell apoptosis and Hsp90 client proteins. It also exhibited a stronger binding affinity to Hsp90 than 17-AAG using molecular docking. Considering the superiority effects on Hsp90 affinity, cell growth, cell cycle, apoptosis, and Hsp90 client proteins, SNX-25a is supposed as a potential anticancer agent that needs to be explored in detail.

Abstract 353: Triciribine, a Selective Akt Inhibitor, Inhibits Myofibroblast Differentiation and Ameliorates Pulmonary Vascular Remodeling in Pulmonary Hypertension

Objectives: Idiopathic pulmonary fibrosis (IPF) is an incurable, chronic and progressive disease with severely poor prognosis and often leads to pulmonary hypertension (PH). Persistent myofibroblast (MF) differentiation in response to TGFβ, marked by de novo expression of αSMA stress fibers, is the central orchestrator of tissue fibrosis and vasculopathy. Our previous studies indicated the integral role of Akt in myofibroblast differentiation and fibrosis. Here, we investigated the efficacy of Triciribine (TCBN), a selective Akt inhibitor, currently in clinical trials for cancer therapy, as a potential therapeutic option for IPF and PH. Methods: WT and Akt1 null mice, as well as those treated with TCBN were subjected to 3 week hypoxia along with normoxia control, and the lungs were used for imaging and western analysis to study the biochemical, structural and vascular changes in the lungs. Cutting edge techniques such as microfil-cast based vascular imaging, confocal imaging and analysis of extracellular matrix protein turnover was performed for the data collection and analysis. Results: Under hypoxia, WT mice exhibited robust vascular remodeling leading to thickening of the artery wall, reduction in lumen size and loss of capillaries in the lungs. This effect was significantly less in Akt1 null mice. Treatment with TCBN significantly ameliorated vascular remodeling in mice due to hypoxia, and resulted in normalization of the vasculature with increased lumen size, reduced wall thickness and increased number of capillary branches as compared to untreated controls. TCBN also affected expression of a number of different extracellular matrix proteins and matrix metalloproteases in addition to changes in the expression of contractile proteins alpha-actin, myocardin and serum response factor in the adventitial fibroblasts. Conclusions: Our results demonstrate the crucial role of Akt as an integral mediator of MF differentiation in IPF and PH. Further, TCBN could potentially be a therapeutic option for IPF and PH.

Near-infrared dye loaded polymeric nanoparticles for cancer imaging and therapy and cellular response after laser-induced heating

Background: In the past decade, researchers have focused on developing new biomaterials for cancer therapy that combine imaging and therapeutic agents. In our study, we use a new biocompatible and biodegradable polymer, termed poly(glycerol malate co-dodecanedioate) (PGMD), for the synthesis of nanoparticles (NPs) and loading of near-infrared (NIR) dyes. IR820 was chosen for the purpose of imaging and hyperthermia (HT). HT is currently used in clinical trials for cancer therapy in combination with radiotherapy and chemotherapy. One of the potential problems of HT is that it can up-regulate hypoxia-inducible factor-1 (HIF-1) expression and enhance vascular endothelial growth factor (VEGF) secretion.Results: We explored cellular response after rapid, short-term and low thermal dose laser-IR820-PGMD NPs (laser/NPs) induced-heating, and compared it to slow, long-term and high thermal dose heating by a cell incubator. The expression levels of the reactive oxygen species (ROS), HIF-1 and VEGF following the two different modes of heating. The cytotoxicity of NPs after laser/NP HT resulted in higher cell killing compared to incubator HT. The ROS level was highly elevated under incubator HT, but remained at the baseline level under the laser/NP HT. Our results show that elevated ROS expression inside the cells could result in the promotion of HIF-1 expression after incubator induced-HT. The VEGF secretion was also significantly enhanced compared to laser/NP HT, possibly due to the promotion of HIF-1. In vitro cell imaging and in vivo healthy mice imaging showed that IR820-PGMD NPs can be used for optical imaging.Conclusion: IR820-PGMD NPs were developed and used for both imaging and therapy purposes. Rapid and short-term laser/NP HT, with a low thermal dose, does not up-regulate HIF-1 and VEGF expression, whereas slow and long term incubator HT, with a high thermal dose, enhances the expression of both transcription factors.