All Publications

  • Emerging Strategies for Developing Next-Generation Protein Therapeutics for Cancer Treatment TRENDS IN PHARMACOLOGICAL SCIENCES Kintzing, J. R., Interrante, M. V., Cochrane, J. R. 2016; 37 (12): 993-1008


    Protein-based therapeutics have been revolutionizing the oncology space since they first appeared in the clinic two decades ago. Unlike traditional small-molecule chemotherapeutics, protein biologics promote active targeting of cancer cells by binding to cell-surface receptors and other markers specifically associated with or overexpressed on tumors versus healthy tissue. While the first approved cancer biologics were monoclonal antibodies, the burgeoning field of protein engineering is spawning research on an expanded range of protein formats and modifications that allow tuning of properties such as target-binding affinity, serum half-life, stability, and immunogenicity. In this review we highlight some of these strategies and provide examples of modified and engineered proteins under development as preclinical and clinical-stage drug candidates for the treatment of cancer.

    View details for DOI 10.1016/

    View details for Web of Science ID 000389393400003

    View details for PubMedID 27836202

  • Engineered knottin peptides as diagnostics, therapeutics, and drug delivery vehicles CURRENT OPINION IN CHEMICAL BIOLOGY Kintzing, J. R., Cochran, J. R. 2016; 34: 143-150


    Inhibitor cystine-knots, also known as knottins, are a structural family of ultra-stable peptides with diverse functions. Knottins and related backbone-cyclized peptides called cyclotides contain three disulfide bonds connected in a particular arrangement that endows these peptides with high thermal, proteolytic, and chemical stability. Knottins have gained interest as candidates for non-invasive molecular imaging and for drug development as they can possess the pharmacological properties of small molecules and the target affinity and selectively of protein biologics. Naturally occurring knottins are clinically approved for treating chronic pain and GI disorders. Combinatorial methods are being used to engineer knottins that can bind to other clinically relevant targets in cancer, and inflammatory and cardiac disease. This review details recent examples of engineered knottin peptides; their use as molecular imaging agents, therapeutics, and drug delivery vehicles; modifications that can be introduced to improve peptide folding and bioactivity; and future perspectives and challenges in the field.

    View details for DOI 10.1016/j.cbpa.2016.08.022

    View details for Web of Science ID 000389103600019

    View details for PubMedID 27642714

  • Integrin-Targeting Knottin Peptide-Drug Conjugates Are Potent Inhibitors of Tumor Cell Proliferation. Angewandte Chemie (International ed. in English) Cox, N., Kintzing, J. R., Smith, M., Grant, G. A., Cochran, J. R. 2016; 55 (34): 9894-9897


    Antibody-drug conjugates (ADCs) offer increased efficacy and reduced toxicity compared to systemic chemotherapy. Less attention has been paid to peptide-drug delivery, which has the potential for increased tumor penetration and facile synthesis. We report a knottin peptide-drug conjugate (KDC) and demonstrate that it can selectively deliver gemcitabine to malignant cells expressing tumor-associated integrins. This KDC binds to tumor cells with low-nanomolar affinity, is internalized by an integrin-mediated process, releases its payload intracellularly, and is a highly potent inhibitor of brain, breast, ovarian, and pancreatic cancer cell lines. Notably, these features enable this KDC to bypass a gemcitabine-resistance mechanism found in pancreatic cancer cells. This work expands the therapeutic relevance of knottin peptides to include targeted drug delivery, and further motivates efforts to expand the drug-conjugate toolkit to include non-antibody protein scaffolds.

    View details for DOI 10.1002/anie.201603488

    View details for PubMedID 27304709

  • Targeted Drug Delivery with an Integrin-Binding Knottin-Fc-MMAF Conjugate Produced by Cell-Free Protein Synthesis MOLECULAR CANCER THERAPEUTICS Currier, N. V., Ackerman, S. E., Kintzing, J. R., Chen, R., Interrante, M. F., Steiner, A., Sato, A. K., Cochran, J. R. 2016; 15 (6): 1291-1300
  • Targeted Drug Delivery with an Integrin-Binding Knottin-Fc-MMAF Conjugate Produced by Cell-Free Protein Synthesis. Molecular cancer therapeutics Currier, N. V., Ackerman, S. E., Kintzing, J. R., Chen, R., Filsinger Interrante, M., Steiner, A., Sato, A. K., Cochran, J. R. 2016; 15 (6): 1291-1300


    Antibody-drug conjugates (ADC) have generated significant interest as targeted therapeutics for cancer treatment, demonstrating improved clinical efficacy and safety compared with systemic chemotherapy. To extend this concept to other tumor-targeting proteins, we conjugated the tubulin inhibitor monomethyl-auristatin-F (MMAF) to 2.5F-Fc, a fusion protein composed of a human Fc domain and a cystine knot (knottin) miniprotein engineered to bind with high affinity to tumor-associated integrin receptors. The broad expression of integrins (including ?v?3, ?v?5, and ?5?1) on tumor cells and their vasculature makes 2.5F-Fc an attractive tumor-targeting protein for drug delivery. We show that 2.5F-Fc can be expressed by cell-free protein synthesis, during which a non-natural amino acid was introduced into the Fc domain and subsequently used for site-specific conjugation of MMAF through a noncleavable linker. The resulting knottin-Fc-drug conjugate (KFDC), termed 2.5F-Fc-MMAF, had approximately 2 drugs attached per KFDC. 2.5F-Fc-MMAF inhibited proliferation in human glioblastoma (U87MG), ovarian (A2780), and breast (MB-468) cancer cells to a greater extent than 2.5F-Fc or MMAF alone or added in combination. As a single agent, 2.5F-Fc-MMAF was effective at inducing regression and prolonged survival in U87MG tumor xenograft models when administered at 10 mg/kg two times per week. In comparison, tumors treated with 2.5F-Fc or MMAF were nonresponsive, and treatment with a nontargeted control, CTRL-Fc-MMAF, showed a modest but not significant therapeutic effect. These studies provide proof-of-concept for further development of KFDCs as alternatives to ADCs for tumor targeting and drug delivery applications. Mol Cancer Ther; 15(6); 1291-300. 2016 AACR.

    View details for DOI 10.1158/1535-7163.MCT-15-0881

    View details for PubMedID 27197305

  • Sports-related brain injuries: connecting pathology to diagnosis NEUROSURGICAL FOCUS Pan, J., Connolly, I. D., Dangelmajer, S., Kintzing, J., Ho, A. L., Grant, G. 2016; 40 (4)


    Brain injuries are becoming increasingly common in athletes and represent an important diagnostic challenge. Early detection and management of brain injuries in sports are of utmost importance in preventing chronic neurological and psychiatric decline. These types of injuries incurred during sports are referred to as mild traumatic brain injuries, which represent a heterogeneous spectrum of disease. The most dramatic manifestation of chronic mild traumatic brain injuries is termed chronic traumatic encephalopathy, which is associated with profound neuropsychiatric deficits. Because chronic traumatic encephalopathy can only be diagnosed by postmortem examination, new diagnostic methodologies are needed for early detection and amelioration of disease burden. This review examines the pathology driving changes in athletes participating in high-impact sports and how this understanding can lead to innovations in neuroimaging and biomarker discovery.

    View details for DOI 10.3171/2016.1.FOCUS15607

    View details for Web of Science ID 000373476500004

    View details for PubMedID 27032917

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