Daniel J Powell

William Penn University, Filadelfia, Pennsylvania, United States

Are you Daniel J Powell?

Claim your profile

Publications (75)445.32 Total impact

  • Source
    Rachel C Lynn · Takami Matsuyama · Daniel J Powell

    Preview · Article · Nov 2015
  • Source

    Full-text · Article · Nov 2015
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: High-grade serous ovarian cancer (HGSOC) accounts for 70-80% of ovarian cancer deaths, and overall survival has not changed significantly for several decades. In this Opinion article, we outline a set of research priorities that we believe will reduce incidence and improve outcomes for women with this disease. This 'roadmap' for HGSOC was determined after extensive discussions at an Ovarian Cancer Action meeting in January 2015.
    Full-text · Article · Oct 2015 · Nature reviews. Cancer
  • Rachel C Lynn · Daniel J Powell
    [Show abstract] [Hide abstract]
    ABSTRACT: mt is a cross-disciplinary biomedical journal devoted to publishing the most exciting advances in pharmacology and therapeutics, as they pertain to advances in translational and clinical medicine. It is recognized as one of the most prestigious journals in the field. With an impact factor of 6.825*, mt ranks in the top 4.2% of scientific journals in the latest Science Citation Index. Published monthly online and in print.
    No preview · Article · Oct 2015 · Molecular Therapy
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Using lentiviral technology, we recently demonstrated that incorporation of CD27 costimulation into CARs greatly improves antitumor activity and T cell persistence. Still, virus-mediated gene transfer is expensive, laborious and enables long-term persistence, creating therapies which cannot be easily discontinued if toxic. To address these concerns, we utilized a non-integrating RNA platform to engineer human T cells to express FRα-specific, CD27 CARs and tested their capacity to eliminate human FRα+ cancer. Novel CARs comprised of human components were constructed, C4-27z and C4opt-27z, a codon-optimized variant created for efficient expression. Following RNA electroporation, C4-27z and C4opt-27z CAR expression is initially ubiquitous but progressively declines across T cell populations. In addition, C4-27z and C4opt-27z RNA CAR T cells secrete high levels of Th-1 cytokines and display strong cytolytic function against human FRα+ cancers in a time- and antigen-dependent manner. Further, C4-27z and C4opt-27z CAR T cells exhibit significant proliferation in vivo, facilitate the complete regression of fully disseminated human ovarian cancer xenografts in mice and reduce the progression of solid ovarian cancer. These results advocate for rapid progression of C4opt-27z RNA CAR to the clinic and establish a new paradigm for preclinical optimization and validation of RNA CAR candidates destined for clinical translation.
    Full-text · Article · Sep 2015 · Oncotarget

  • No preview · Article · Aug 2015 · Clinical Cancer Research
  • Source

    Full-text · Dataset · Jul 2015
  • [Show abstract] [Hide abstract]
    ABSTRACT: Adoptive transfer of T-cells engineered to express chimeric immunoreceptors is an effective strategy to treat hematological cancers, however, such therapy for solid cancers such as ovarian cancer remains challenging because a safe and effective immunotherapeutic target has not yet been identified. Here, we constructed and evaluated a novel redirected T-cell-based immunotherapy targeting human follicle-stimulating hormone receptor (FSHR), a highly conserved molecule in vertebrate animals with expression limited to gonadal tissues, ovarian cancer and cancer-associated vasculature. Receptor ligand-based anti-FSHR immunoreceptors were constructed that contained small binding fragments from the ligand for FSHR, follicle stimulating hormone (FSH), fused to T-cell transmembrane and T-cell signaling domains. Human T-cells transduced to express anti-FSHR immunoreceptors were specifically immunoreactive against FSHR-expressing human and mouse ovarian cancer cell lines in a MHC-non-restricted manner, and mediated effective lysis of FHSR-expressing tumor cells, but not FSHR-deficient targets, in vitro. Similarly, the outgrowth of human ovarian cancer xenografts in immunodeficient mice was significantly inhibited by the adoptive transfer of FSHR-redirected T-cells. Our experimental observations show for the first time that FSHR is a promising immunotherapeutic target for ovarian cancer and supports further exploration of FSHR-targeted immune therapy approaches for cancer patients. Copyright © 2015, American Association for Cancer Research.
    No preview · Article · Jun 2015
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Chimeric antigen receptors (CARs) can redirect T cells against antigen-expressing tumors in an HLA-independent manner. To date, various CARs have been constructed using mouse single chain antibody variable fragments (scFvs) of high affinity that are immunogenic in humans and have the potential to mediate "on-target" toxicity. Here, we developed and evaluated a fully human CAR comprised of the human C4 folate receptor-alpha (αFR)-specific scFv coupled to intracellular T cell signaling domains. Human T cells transduced to express the C4 CAR specifically secreted proinflammatory cytokine and exerted cytolytic functions when cultured with αFR-expressing tumors in vitro. Adoptive transfer of C4 CAR T cells mediated the regression of large, established human ovarian cancer in a xenogeneic mouse model. Relative to a murine MOv19 scFv-based αFR CAR, C4 CAR T cells mediated comparable cytotoxic tumor activity in vitro and in vivo but had lower affinity for αFR protein and exhibited reduced recognition of normal cells expressing low levels of αFR. Thus, T cells expressing a fully human CAR of intermediate affinity can efficiently kill antigen-expressing tumors in vitro and in vivo and may overcome issues of transgene immunogenicity and "on-target off-tumor" toxicity that plague trials utilizing CARs containing mouse-derived, high affinity scFvs.
    Full-text · Article · Jun 2015 · Oncotarget
  • Katarzyna Urbanska · Daniel J Powell

    No preview · Article · Jun 2015 · Immunotherapy
  • Phillip P Santoiemma · Daniel J Powell
    [Show abstract] [Hide abstract]
    ABSTRACT: The accumulation of tumor infiltrating lymphocytes (TILs) in ovarian cancer is prognostic for increased survival while increases in immunosuppressive regulatory T-cells (Tregs) are associated with poor outcomes. Approaches that bolster tumor-reactive TILs may limit tumor progression. However, identifying tumor-reactive TILs in ovarian cancer has been challenging, though adoptive TIL therapy in patients has been encouraging. Other forms of TIL immunomodulation remain under investigation including Treg depletion, antibody-based checkpoint modification, activation and amplification using dendritic cells, antigen presenting cells or IL-2 cytokine culture, adjuvant cytokine injections, and gene-engineered T-cells. Many approaches to TIL manipulation inhibit ovarian cancer progression in preclinical or clinical studies as monotherapy. Here, we review the impact of TILs in ovarian cancer and attempts to mobilize TILs to halt tumor progression. We conclude that effective TIL therapy for ovarian cancer is at the brink of translation and optimal TIL activity may require combined methodologies to deliver clinically-relevant treatment.
    No preview · Article · Apr 2015 · Cancer biology & therapy
  • [Show abstract] [Hide abstract]
    ABSTRACT: T cells expressing a chimeric antigen receptor (CAR) can produce dramatic results in lymphocytic leukemia patients; however, therapeutic strategies for myeloid leukemia remain limited. Folate receptor beta (FRβ) is a myeloid-lineage antigen expressed on 70% of acute myeloid leukemia (AML) patient samples. Here, we describe development and evaluation of the first CARs specific for human FRβ (m909) in vitro and in vivo. m909 CAR T cells exhibited selective activation and lytic function against engineered C30-FRβ as well as endogenous FRβ(+) AML cell lines in vitro. In mouse models of human AML, m909 CAR T cells mediated the regression of engrafted FRβ(+) THP1 AML in vivo. In addition, we demonstrated that treatment of AML with all-trans retinoic acid (ATRA) enhanced FRβ expression, resulting in improved immune recognition by m909 CAR T cells. As many cell-surface markers are shared between AML blasts and healthy hematopoietic stem and progenitor cells (HSCs), we evaluated FRβ expression and recognition of HSCs by CAR T cells. m909 CAR T cells were not toxic against healthy human CD34+ HSCs in vitro. Our results indicate that FRβ is a promising target for CAR T cell therapy of AML, which may be augmented by combination with ATRA. Copyright © 2015 American Society of Hematology.
    No preview · Article · Apr 2015 · Blood
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Vaccination strategies incorporating the immunodominant HLA-A2-restricted HER2/neu-derived peptide 369-377 (HER2369-377) are increasingly utilized in HER2/neu-expressing cancer patients. The failure of post-vaccination HER2369-377-specific CD8(+) T-cells to recognize HLA-A2(pos) HER2/neu-expressing cells in vitro, however, has been attributed to impaired MHC class I/HLA-A2 presentation observed in HER2/neu-overexpressing tumors. We reconcile this controversy by demonstrating that HER2369-377 is directly recognized by high functional-avidity HER2369-377-specific CD8(+) T-cells-either genetically modified to express a novel HER2369-377-TCR or sensitized using HER2369-377-pulsed type 1-polarized dendritic cells (DC1)-on class I-abundant HER2(low), but not class I-deficient HER2(high), cancer cells. Importantly, a critical cooperation between CD4(+) T-helper type-1 (Th1) cytokines IFN-γ/TNF-α and HER2/neu-targeted antibody trastuzumab is necessary to restore class I expression in HER2(high) cancers, thereby facilitating recognition and lysis of these cells by HER2369-377-specific CD8(+) T-cells. Concomitant induction of PD-L1 on HER2/neu-expressing cells by IFN-γ/TNF and trastuzumab, however, has minimal impact on DC1-sensitized HER2369-377-CD8+ T-cell-mediated cytotoxicity. Although activation of EGFR and HER3 signaling significantly abrogates IFN-γ/TNF-α and trastuzumab-induced class I restoration, EGFR/HER3 receptor blockade rescues class I expression and ensuing HER2369-377-CD8(+) cytotoxicity of HER2/neu-expressing cells. Thus, combinations of CD4(+) Th1 immune interventions and multivalent targeting of HER family members may be required for optimal anti-HER2/neu CD8(+) T-cell-directed immunotherapy. Copyright © 2015, American Association for Cancer Research.
    Full-text · Article · Mar 2015
  • [Show abstract] [Hide abstract]
    ABSTRACT: Purpose: Chemokines are implicated in T cell trafficking. We mapped the chemokine landscape in advanced stage ovarian cancer and characterized the expression of cognate receptors in autologous DC-vaccine primed T cells in the context of cell-based immunotherapy. Experimental design: The expression of all known human chemokines in patients with primary ovarian cancer was analyzed on two independent microarray datasets and validated on tissue microarray. Peripheral blood T cells from five HLA-A2 patients with recurrent ovarian cancer, who previously received autologous tumor DC vaccine, underwent CD3/CD28 costimulation and expansion ex vivo. Tumor-specific T cells were identified by HER2/neu pentamer staining and were evaluated for the expression and functionality of chemokine receptors important for homing to ovarian cancer. Results: The chemokine landscape of ovarian cancer is heterogeneous with high expression of known lymphocyte-recruiting chemokines (CCL2, CCL4 and CCL5) in tumors with intraepithelial T cells, whereas CXCL10, CXCL12 and CXCL16 are expressed quasi-universally, including in tumors lacking tumor infiltrating T cells. DC-vaccine primed T cells were found to express the cognate receptors for the above chemokines. Ex vivo CD3/CD28 costimulation and expansion of vaccine-primed T cells upregulated CXCR3 and CXCR4, and enhanced their migration toward universally expressed chemokines in ovarian cancer. Conclusions: DC-primed tumor specific T cells are armed with the appropriate receptors to migrate towards universal ovarian cancer chemokines, and these receptors are further upregulated by ex vivo CD3/CD28 costimulation, which render T cells more fit for migrating towards these chemokines. Copyright © 2015, American Association for Cancer Research.
    No preview · Article · Feb 2015 · Clinical Cancer Research

  • No preview · Article · Jan 2015 · Cancer Research
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background Redirection of T lymphocytes against tumor antigens can induce dramatic regression of advanced stage malignancy. The use of bispecific antibodies (BsAbs) that bind both the T-cell receptor (TCR) and a target antigen is one promising approach to T-cell redirection. However, BsAbs indiscriminately bind all CD3+ T-cells and trigger TCR activation in the absence of parallel costimulatory signals required to overcome T-cell unresponsiveness or anergy.Methods To address these limitations, a combination platform was designed wherein a unique BsAb referred to as frBsAb exclusively engages T-cells engineered to express a novel chimeric receptor comprised of extracellular folate receptor fused to intracellular TCR and CD28 costimulatory signaling domains in tandem; a BsAb-binding immune receptor (BsAb-IR). As a surrogate TCR, the BsAb-IR allows for concomitant TCR and costimulatory signaling exclusively in transduced T-cells upon engagement with specific frBsAbs, and can therefore redirect T-cells on command to desired antigen. Human primary T-cells were transduced with lentiviral vector and expanded for 14¿18 days. BsAb-IRs were harvested and armed with frBsAbs to test for redirected cytotoxicity against CD20 positive cancer cell lines.ResultsUsing frBsAbs specific for CD20 or HER2, the lytic activity of primary human T-cells expressing the BsAb-IR was specifically redirected against CD20+ leukemic cells or HER2+ epithelial cancer cells, respectively, while non-engineered T-cells were not activated. Notably, elimination of the CD28 costimulatory domain from the BsAb-IR construct significantly reduced frBsAb-redirected antitumor responses, confirming that frBsAbs are capable of delivering simultaneous TCR activation and costimulatory signals to BsAb-IR T-cells.Conclusion In summary, our results establish the proof of concept that the combination of BsAbs with optimized gene-engineered T-cells provides the opportunity to specify and augment tumor antigen-specific T-cell activation and may improve upon the early success of conventional BsAbs in cancer immunotherapy.
    Full-text · Article · Dec 2014 · Journal of Translational Medicine
  • [Show abstract] [Hide abstract]
    ABSTRACT: Aberrant blood vessels enable tumor growth, provide a barrier to immune infiltration, and serve as a source of pro-tumorigenic signals. Targeting tumor blood vessels for destruction, or tumor vascular disruption therapy, can therefore provide significant therapeutic benefit. Here we describe the ability of chimeric antigen receptor (CAR) bearing T cells to recognize human PSMA (hPSMA) on endothelial targets in vitro as well as in vivo. CAR T cells were generated using the anti-PSMA scFv, J591, and the intracellular signaling domains: CD3 zeta, CD28, and/or CD137/4-1BB. We found that all anti-hPSMA CAR T cells recognized and eliminated PSMA+ endothelial targets in vitro, regardless of signaling domain. T cells bearing the 3rd generation anti-hPSMA CAR, P28BBζ, were able to recognize and kill primary human endothelial cells isolated from gynecological cancers. In addition, the P28BBζ CAR T cells mediated regression of hPSMA-expressing vascular neoplasms in mice. Finally, in murine ovarian cancers models populated by murine vessels expressing hPSMA, the P28BBζ CAR T cells were able to ablate PSMA+ vessels, cause secondary depletion of tumor cells, and reduce tumor burden. Taken together, these results provide strong rationale for the use of CAR T cells as agents of tumor vascular disruption, specifically those targeting PSMA.
    No preview · Article · Oct 2014
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The ErbB2 protein is a member of the tyrosine kinase family of growth factor receptors that is overexpressed in cancers of the breast, ovary, stomach, kidney, colon, and lung, and therefore represents an attractive candidate antigen for targeted cancer immunotherapy. Cytotoxic T lymphocytes specific for various immunogenic ErbB2 peptides have been described, but they often exhibit both poor functional avidity and tumor reactivity. In order to generate potent CD8(+) T cells with specificity for the ErbB2(369-377) peptide, we performed one round of in vitro peptide stimulation of CD8(+) T cells isolated from an HLA-A2(+) patient who was previously vaccinated with autologous dendritic cells pulsed with HLA class I ErbB2 peptides. Using this approach, we enriched highly avid ErbB2-reactive T cells with strong ErbB2-specific, antitumor effector functions. We then stimulated these ErbB2-reactive T cells with ErbB2(+) HLA-A2(+) tumor cells in vitro and sorted tumor-activated ErbB2(369-377) peptide T cells, which allowed for the isolation of a novel T-cell receptor (TCR) with ErbB2(369-377) peptide specificity. Primary human CD8(+) T cells genetically modified to express this ErbB2-specific TCR specifically bound ErbB2(369-377) peptide containing HLA-A2 tetramers, and efficiently recognized target cells pulsed with low nanomolar concentrations of ErbB2(369-377) peptide as well as nonpulsed ErbB2(+) HLA-A2(+) tumor cell lines in vitro. In a novel xenograft model, ErbB2-redirected T cells also significantly delayed progression of ErbB2(+) HLA-A2(+) human tumor in vivo. Together, these results support the notion that redirection of normal T-cell specificity by TCR gene transfer can have potential applications in the adoptive immunotherapy of ErbB2-expressing malignancies.
    Full-text · Article · Jul 2014 · Human Gene Therapy

  • No preview · Article · Apr 2014 · Cancer Research
  • Source

    Full-text · Dataset · Feb 2014

Publication Stats

3k Citations
445.32 Total Impact Points


  • 2009-2015
    • William Penn University
      Filadelfia, Pennsylvania, United States
  • 2008-2015
    • University of Pennsylvania
      • • Department of Pathology and Laboratory Medicine
      • • Department of Medicine
      • • Ovarian Cancer Research Center
      Filadelfia, Pennsylvania, United States
    • University of Texas Southwestern Medical Center
      • Center for Cancer Immunobiology
      Dallas, Texas, United States
    • Howard Hughes Medical Institute
      Ashburn, Virginia, United States
  • 2004-2008
    • National Institutes of Health
      • Branch of Surgery
      Bethesda, MD, United States
  • 2006
    • National Cancer Institute (USA)
      • Surgery Branch
      Bethesda, MD, United States