Using Gold Nanoparticles to Improve Prostate Cancer Treatment

Gold nanoparticles that convert infrared light to heat are safe and effective in removing low- to intermediate-grade prostate tumors, as per a study published in Proceedings of the National Academy of Sciences. This treatment could potentially offer patients a targeted therapy treatment that avoids damaging essential structures within the prostate, eliminating the common side effects tethered to common treatments such as removal of the entire gland. This work was carried out by researchers at the Icahn School of Medicine.

Using Nanoparticles to Minimize Damage

Led by Ardeshir Rastinehad, DO, this study tested the effectiveness of AuroLase Therapy, a treatment from the medical device company Nanospectra Biosciences. AuroLase is based on technology created by researchers Naomi Halas, PhD, and Jennifer West, PhD at Rice University. Rastinehad invented the technique used in this trial to treat prostate cancer cells using an MR US fusion guided platform. This platform was custom made through a partnership with Philips Healthcare.

The gold-silica nanoshells used in the AuroLase Therapy are particles that Halas created, consisting of a silica core and a gold shell measuring 150 nanometers in diameter. These shells are designed to absorb near-infrared light, convert this energy to heat, then cause selective cell death in malignant cells. In doing so, this treatment minimizes damage to the adjacent, healthy cells.

“Gold-silica nanoshells infusion allows for a focused therapy that treats the cancer, while sparing the rest of the prostate, thus preserving a patient’s quality of life by reducing unwanted side effects, which could include erectile dysfunction and/or the leakage of urine,” said Dr. Rastinehad, Associate Professor of Urology, and Radiology, at the Icahn School of Medicine at Mount Sinai.

After the treatment is complete, these nanoparticles are processed by the liver. Although some particles may remain within the liver and spleen, no side effects have been identified. Preclinical studies involving cell and animal models showed this treatment to be effective, giving Rastinehad and colleagues confidence going into this most recent clinical trial.

Background of the Icahn Study

In their trial, the researchers recruited 16 men between ages 58 and 79, all of whom having low- to intermediate-grade prostate cancer. Each of these patients was diagnosed and treated at The Mount Sinai Hospital using magnetic resonance-ultrasound fusion imaging, a technique that uses MRI imaging to extract a tissue biopsy. These patients received both the gold nanoparticle infusion and laser ablation to operate on the tumor. Post-operative MRIs were taken of the prostate 2-3 days after the surgery, MRI-targeted fusion biopsies taken at 3 and 12 months, and a traditional biopsy was taken after one year. This was conducted as an outpatient procedure, with participants leaving the hospital after being monitored for a few hours post-operation.

The researchers found that the use of gold nanoparticles and laser ablation had success in 87.5% of the cancers treated at 12-month follow-up. The primary goal in this work was to see that the cancer cells were fully eliminated in the biopsy.

“Mount Sinai’s interventional urology program is research-driven and offers patients minimally invasive treatment therapies that improve quality of life,” noted Ash Tewari, MBBS, MCh, Chair of the Department of Urology at the Mount Sinai Health System and the Kyung Hyun Kim, MD Professor of Urology at the Icahn School of Medicine at Mount Sinai. “Dr. Rastinehad’s gold nanoparticle research shows that patients are not only benefiting from this treatment, but also experiencing minimal side effects.”