Carlie S. Mendoza ’16 is helping to hunt down cancer cells. As cancer continues to kill at a rate exceeded only by heart disease, Mendoza feels compelled to aid patients in fighting the disease. As an undergraduate researcher in the lab of Professor Ulrich B. Wiesner, Materials Science and Engineering, Mendoza works toward perfecting the next generation of cancer hunters, called the Cornell Prime Dots, or C’ Dots.
From Cornell Dots, C Dots, to Cornell Prime Dots, C’ Dots: How They Work
C’ Dots are designed to locate cancer cells in the body. They are core-shell nanoparticles used in therapeutics, theranostics, and diagnostics related to cancer. As evident from their name, core-shell particles consist of an outer shell and an inner core. C’ Dots are mostly made of silica; the silica shell provides stability and compatibility with the biological environment inside the body. The shell is further covered with polyethylene glycol (PEGs) to prevent the immune system from attacking the C’ Dots.
As for their ability to seek out cancer cells, the C’ Dots shells have targeting ligands that bind to cancer cells. Inside each particle is a core filled with fluorescent dye used for optical visualization inside the body. The result is a particle less than 10 nm in diameter that locates cancer cells accurately and effectively, without significant impact on the human body.
Though impressive, C’ Dots are not a first iteration; Mendoza is actually working on second-generation dots. The first-generation particles, the Cornell Dots or C Dots, have undergone clinical trials in humans at the Memorial Sloan Kettering Cancer Center (MSKCC). Invented by Wiesner, the C Dots have undergone FDA-approved trials since 2011, and results of the first trial in late 2014 suggested they are safe for human use. It is the first inorganic material of its size tested as an investigational new drug under FDA approval. In the latest ongoing trials, the fluorescence capability of C Dots is utilized together with a handheld optical camera system, allowing surgeons to see cancer cells that have been made to glow during surgery.
The new C’ Dots are an improvement over their predecessor. Currently undergoing clinical trial as well, they have optimized properties, especially in brightness, and are therefore more promising. “What’s new in the C’ Dot is that we changed the way it is synthesized as well as its compositions,” says Mendoza. “That way its dyes interact differently with the matrix, and that helps with the C’ Dots’ optical properties. The new generation of dots is therefore brighter and simpler to manufacture.”
Mendoza is responsible for producing C’ Dots under different parameters, such as the pH, the amount of silica added, and the type of silica used. The goal is to further enhance the nanoparticles and improve qualities such as their brightness. A batch of C’ Dots contains around 10 million particles and takes seven days to produce. Once done and analyzed, they are delivered to the MSKCC for trials.
Inspired by C Dots
Mendoza’s interest in cancer-related research dates back to her freshman year of high school, when she was taking a research class and studying new developments related to cancer. It was, in fact, the C Dot that inspired her. She saw Wiesner’s research on the news, contacted him, and later met him in New York City where he was giving a talk. Wiesner was very welcoming, says Mendoza, and the two kept in contact.
Mendoza’s interest in cancer-related research dates back to her freshman year of high school. . . . She saw Wiesner’s research on the news, contacted him, and later met him in New York City where he was giving a talk.
When Mendoza enrolled at Cornell and in the Hunter R. Rawlings III Cornell Presidential Research Scholar program, she chose Professor Wiesner as her research mentor.
Despite the complex and often confounding subject, Mendoza loves her research experience. “It’s great; it’s very collaborative,” she says. “When I started out, I was the only undergraduate student. It was intimidating, and I kept asking myself how I could fit in this group with so many graduate students and the professor. But they are very nice and helpful; whenever I have trouble in the lab, I can ask anyone and they are happy to help.”
She specifically credits her graduate student mentor, Kai Ma, for tirelessly assisting her and explaining difficult concepts. “I started my research working with Kai Ma, and he is really enthusiastic,” says Mendoza. “He always has a lot of ideas, and he doesn’t just tell me what to do, but gives me options. He also ties everything back to my background as a biology major, and what I’m interested in, which is application.”
Mendoza’s Active Cornell Life
Today, Mendoza is far more comfortable with her work. In addition, she has garnered knowledge that may be hard to find in the classroom. She hopes other undergraduate students can experience research, too. “I’ve learned things that I wouldn’t have learned, especially going into a field outside my comfort zone. It really opened my eyes,” she says.
Dedicated to her search for cancer cells, Mendoza admits with a laugh that she spends a lot of her time doing research. Still, she does not forget to look beyond the flasks and chemicals she works with. She is involved in the Cornell Filipino Association. She is currently a teaching assistant for a Principles of Biochemistry course, and she TA’d for the Art of Horticulture the previous semester. “I’m also a Girl Scout,” she adds, with a smile.
Mendoza’s efforts to help cancer patients extend beyond research. She is part of the Cornell Commitment Leadership Program and, together with her sister, started a project called Cranes for Cancer. They craft origami cranes and homemade cards to be sent to cancer patients. “I feel I have a commitment to help,” Mendoza says.
Indeed, compassion is a recurring theme in Mendoza’s endeavors. “Once we perfect [the C’ Dots], we will be able to help a lot of patients and have a positive impact on their lives,” she says. “That’s what motivates me to go to the lab every day.”