Progress Report: Shelton Earp, MD; Joseph Desimone, Ph.D

Co-Investigator: Shelton Earp, MD– Director and Lineberger Professor, Professor of Medicine and Pharmacology, Lineberger Comprehensive Cancer Center, University of North Carolina-Chapel Hill

Co-Investigator: Joseph DeSimone, PhD–Chancellor’s Eminent Professor of Chemistry, University of North Carolina-Chapel Hill, William R. Kenan, Jr. Distinguished Professor of Chemical Engineering, North Carolina State University

Application of Nanotechnology to Novel Models of Prostate Cancer—Nanoscale Fabrication Technology May Provide New Modeling Capabilities and Therapies to Arrest Lethal Prostate Cancer Progression

The goal of this project was to develop nanoparticles that deliver novel cancer medicines specifically to prostate tumors. Nanoparticles are very small objects (the size of a virus) that are being developed as drug delivery vehicles. Dr. DeSimone has developed two distinct nanoparticle compositions that are generally safe and can therefore be used to treat patients by intravenous injection. The particles are decorated with molecules that target prostate cancer cells and not healthy cells. The biology team led by Dr. Earp loaded these targeted nanoparticles with two different cancer medicines, docetaxel (a chemotherapy medicine) and siRNAs (small interfering RNA: molecules that can silence cancer-causing genes), a fragile biologic cargo. Data reported in their progress report shows that nanoparticles containing docetaxel were much more effective at killing cancer cells than treatment with docetaxel alone. The nanoparticles were able to deliver 40% total weight of docetaxel, which is 16 times greater than any other reported nanoparticle drug delivery vehicle. A proof-of-concept was reported showing that nanoparticles could encapsulate siRNA that could be successfully released into cancer cells. The use of siRNAs in cancer therapy is a major goal because these molecules can inhibit currently “undruggable” targets with precise selectivity. The team is currently working on delivering an siRNA specific to Ack1 to prostate cancer cells. Ack1 is a gene hypothesized to play a critical role in prostate cancer initiation, progression and recurrence because of its integral role in androgen receptor signaling, a central prostate cancer survival pathway. Early data shows that Ack1 is activated in human prostate cancers and that it may directly enhance the activity of androgen receptor. The advancements made in this creativity award project open up new strategies for treating advanced prostate cancer through the design of new mechanisms to deliver novel medicines directly to prostate cancer cells.

Terms to know from this article:

Progression

Increase in the size of a tumor or spread of cancer in the body.

androgen

A type of hormone that promotes the development and maintenance of male sex characteristics.

Gene

The functional and physical unit of heredity passed from parent to offspring. Genes are pieces of DNA, and most genes contain the information for making a specific protein.