Week 2

Week 2 has been just as interesting as the first week was! Last week, we labeled two sets of nanoparticles, one meant to target NSCLC and one non-targeting particle, with Zr-89. The first set of particles were injected into mice with NSCLC. These mice were sacrificed and dissected last week, and their organs were harvested to analyze the biodistribution of the particles. This week, the second set of particles were injected into mice with breast cancer tumors, followed by euthanization, dissection, and organ harvesting. These non-targeting particles were used to quantify the EPR effect on particle distribution in breast cancer tumor-bearing mice. Using a gamma counter, we measured the radioactivity present in each of the organs for each set of mice. These values were then normalized to the mass of each organ to compare the uptake of our particles in the tumor compared to the rest of the body.

We radiolabeled two more sets of particles this week, one meant to target prostate cancer and one meant to target NSCLC. We are assessing the stability over time of these particles in various media including PBS, mouse serum, and human serum. To analyze their stability, we are performing instant thin layer chromatography (ITLC) to separate and quantify radiolabeled particles from free Zr89.

In addition to conducting the radiolabeled-nanoparticle studies, we also dissociated two tumors to isolate primary cancer cells. One tumor is a prostate cancer model, while the other tumor is a SCLC model.

On the clinical side, Dr. Bradbury is going to introduce me to all the tools and sensors that have been developed to better visualize our particles in patients. These devices are used by the surgeon to help identify which lymph nodes are cancer positive in patients (mainly melanoma patients). The standard method of identifying positive nodes uses a radiotracer, fluorescent dye, and gamma detector. This technique is somewhat effective, but the surgeon is not always certain that they are resecting the correct lymph nodes because the radiotracers and fluorescent dyes do not bind specifically to cancer cells. It is only determined hours later, upon pathological inspection, if the resected lymph node did in fact have cancer cells present. By using the targeting, dual-modality, radiolabeled fluorescent particles and detectors that we have developed, surgeons can see exactly which lymph nodes have been infiltrated by cancer cells during surgery. Dr. Bradbury will show me videos of patient surgeries in which all these components are being utilized and how they compare to the current techniques.

Outside of lab, I got to see the Museum of Modern Art (MoMA), the Statue of Liberty, Ellis Island, and the World Trade Center/Ground Zero.