Rochester, Minnesota Clinical Profile


The research laboratory of John C. Morris III, M.D., studies the potential utility of the thyroidal iodide transporter — the sodium/iodide symporter (NIS) — as a therapeutic gene for gene therapy. Prostate cancer is used as a model.

Focus areas

  • NIS-mediated gene therapy using radioiodine. Dr. Morris and his colleagues have induced prostate cancer cells to express NIS using an expression vector in which the NIS cDNA is coupled to the prostate-specific antigen (PSA) promoter. This vector allows prostate-specific and androgen-sensitive NIS expression as measured by iodide trapping and Western blotting.

    Dr. Morris has demonstrated this activity both in vitro and in vivo, and he's also shown that NIS expression can be induced by adenoviral-mediated gene transfer into prostate cancer xenografts. This uptake is sufficiently high that the tumors can be effectively treated with radioactive iodine, achieving as high as 80 percent complete responses.

    Dr. Morris and his colleagues are currently conducting a phase I clinical trial of this therapy in men who have recurrent prostate cancer confined to the prostate bed. In addition, they are generating replication-competent virus vectors that express NIS to target metastatic and androgen-resistant prostate cancer.

Significance to patient care

The goal of Dr. Morris' work is to develop and apply a novel gene therapy approach to metastatic, hormone-resistant prostate cancer using radioactive as the therapeutic moiety.

Professional highlights

  • Chief Operating Officer, American Thyroid Association, 2011-present
  • Chair, Laboratory Services Committee, American Thyroid Association, 2005-2009
  • Board of Directors, American Thyroid Association, 2001-2005
  • Chair, Scientific Program Committee, American Thyroid Association Annual Meeting, 1999


Administrative Appointment

  1. Emeritus, Division of Endocrinology, Diabetes, Metabolism, Nutrition, Department of Internal Medicine

Academic Rank

  1. Professor of Medicine


  1. Research Fellowship Mayo Medical School, Mayo Clinic College of Medicine
  2. Resident Endocrinology, Programs in Rochester, Mayo School of Graduate Medical Education, Mayo Clinic College of Medicine
  3. Fellow - Endocrinology Mayo School of Graduate Medical Education, Mayo Clinic College of Medicine
  4. Chief Resident - Internal Medicine University of Tennessee Medical Center at Knoxville
  5. Resident - Internal Medicine University of Tennessee, Knoxville
  6. Internship - Internal Medicine University of Tennessee, Knoxville
  7. MD - Medicine University of Tennessee, Memphis
  8. BS - Biology King College

Clinical Studies

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