Targeted nanoparticles boost platinum-based anticancer therapy



Forty percent of men with prostate cancer may not even know they have it, according to a new research study by the Prostate Cancer Foundation of Chicago. The study revealed the standard office biopsy procedure often isn’t enough to properly detect prostate cancer. This new research will be published in an upcoming issue of Urology,

Full Post: Prostate cancer discovered in 40% of men who test negative for the disease

A research team from the Massachusetts Institute of Technology (MIT)-Harvard Center for Nanotechnology Excellence has custom-designed nanoparticles that can deliver the anticancer drug cisplatin specifically to prostate cancer cells.

The nanoparticles are composed of two different polymers and are decorated with a nucleic acid aptamer that binds to the tumor marker prostate-specific membrane antigen. This aptamer ensures that the nanoparticles deliver their payload only to prostate cancer cells.

Stephen Lippard, Ph.D., and Robert Langer, Ph.D., MIT, and Omid Farokhzad, M.D., Harvard Medical School, led the team that developed this new formation of cisplatin. The investigators published their results in the Proceedings of the NationalAcademy of Sciences of the United States of America.

To construct a stable nanoparticle that would only release its toxic cargo inside tumor cells, the investigators synthesized a modified version of cisplatin that includes a long hydrocarbon chain. As the nanoparticle forms, the hydrocarbon chain associates strongly with the hydrophobic chains of the polymer that forms the nanoparticle’s core. The researchers note that the hydrocarbon chain they chose optimizes both drug encapsulation and drug release inside tumor cells. Once the nanoparticle enters the cell, the modified drug is converted into its active form as a result of chemical conditions inside the cell.

Tests with human cancer cells growing in culture showed that these nanoparticles were taken up specifically by tumor cells and not by healthy cells. Nanoparticles lacking the targeting aptamer were not taken up either. These tests also demonstrated that the nanoparticles release their cargo over the course of 60 hours, providing a sustained lethal level of the drug inside the targeted cells. In addition, the nanoparticle formulation was approximately 100 times more effective at killing tumor cells than was cisplatin by itself.

This work, which is detailed in the paper “Targeted delivery of cisplatin to prostate cancer cells by aptamer functionalized Pt(IV) prodrug-PLGA-PEG nanoparticles,” was supported by the NCI Alliance for Nanotechnology in Cancer, a comprehensive initiative designed to accelerate the application of nanotechnology to the prevention, diagnosis, and treatment of cancer. An abstract of this paper is available at the journal’s Web site. View abstract

http://nano.cancer.gov

Link




Antibodies that target epidermal growth factor receptor (EGFR) have proven themselves as potent anticancer drugs. Now, a team of investigators led by Shuming Nie, Ph.D., and Lily Yang, Ph.D., both at the Emory University School of Medicine and members of the Emory-Georgia Tech Nanotechnology Center for Personalized and Predictive Oncology, is aiming to capitalize on

Full Post: Artificial antibody delivers nanoparticles to tumors



Working with a nanoparticle designed to target and image glioblastoma, a form of brain cancer, investigators at the University of Washington in Seattle have found that these same nanoparticles inhibit tumor cell invasion, one of the key events that leads to the metastatic spread of cancer. The investigators have also determined how the nanoparticles exert

Full Post: Toxin-nanoparticle combo inhibits brain cancer invasion while imaging tumors



Given that cancer is a disease caused by gene mutations, cancer researchers have been striving to develop gene therapies aimed at correcting these mutations. However, these efforts have been hobbled by the difficulty in safely and efficiently delivering anticancer genes to tumors. Nanoparticles, however, may solve these delivery issues, and two recently published studies, using

Full Post: Targeted nanoparticles deliver therapeutic DNA to cancer cells



One of the problems that cancer patients face is that many of the most potent anticancer therapies can be administered only by injection, which means that cancer patients must travel to receive their medication. But thanks to a new type of nanoparticle developed by researchers at the Johns Hopkins University School of Medicine, future cancer

Full Post: Polymer nanoparticle for oral anticancer drug delivery



One of the key steps in the development of any drug or imaging agent intended for human use is measurement of the adsorption, metabolism, and excretion of the drug. Quantifying this collection of pharmacological properties, known as ADME, is a challenging and time-consuming process that is even more difficult when the drug or imaging

Full Post: Measuring nanoparticle behavior in the body using MRI