As seen in Psychology Today.
“Precision medicine” is a common buzzword in the world of medicine, largely because so many of the solutions it offers seem so revolutionary. It appears to be the medicine of the future, and many of the procedures and treatments that utilize precision medicine oftentimes seem, for lack of a better term, futuristic. This is especially the case when the new field is described, as it recently was in an article that appeared in Scientific American, as the “interface of biotechnology and materials science.”
As the name suggests, the core of precision medicine is its ability to offer extremely precise data and pinpoint accuracy when delivering medications. They are treatments that can better target the disease while taking into account the patient’s unique biology, genetics, and history, and these novel solutions allow us to treat the disease as it has manifested in each individual patient. Conversely, conventional medicine often casts a wider net; it is designed to help the largest amount of people, but may not be as effective for everyone.
As the technology behind precision medicine is developed, it will allow medical professionals to exponentially improve diagnostics, offer treatments that use highly selective delivery mechanisms, and even design medicines calibrated to fit one’s genetics. These advances in technology will eventually transform virtually all fields of medicines, from psychiatry to oncology.
What follows are some of the advances in precision medicine being explored by medical researchers.
Diagnosing with Nanomedicine
The word “nanomedicine” combines the prefix “nano-” and the word “medicine,” but the actual meaning of this term is not as straightforward as it may first seem. The literal meaning of “nano-” is one billionth of a unit of measurement. For example, a nanometer is one billionth of a meter. For reference, the length of one nanometer is equivalent to the length of three gold atoms. It is almost inconceivably small.
When one speaks of nanomedicine, it does not necessarily involve technological components that are this small, like a computer chip the size of a few gold atoms. Rather, it means that the technology is designed to affect and manipulate matter on the molecular or atomic scale in a therapeutic capacity. It may also refer to a technology that grants medical professionals the ability to better monitor patients and any changes that may take place in their bodies, whether it is the growth of a cancerous tumor or the spread of a neurodegenerative disease.
One of the primary applications for nanomedicines is to improve diagnostics, as it allows for more advanced screening techniques that can better identify diseases at their initial stages, oftentimes when they are only affecting a very small portion of a specific organ or other part of the body. For example, fluorescent-based biosensing and bioimaging have been used for many years to allow medical professionals to detect and analyze biological samples for individual biomarkers that indicate the presence of a disease, but they suffer from sensitivity issues. One example would be if there are low level of antigens in a sample of blood or urine, researchers may not be able to detect them and, consequently, they cannot know that they are there.
Researchers at Washington University in St. Louis, however, have developed a “plasmonic patch” that is embedded with nanomaterials. These materials amplify the signal emitted by existing fluorescent-based tests. As Jingyi Luan, one of the graduate students who worked on the project, said, “These nanostructures act as antennae: they concentrate light into a tiny volume around the molecules emitting the fluorescence.”
By making more precise instruments that are used to detect and monitor biomarkers, we can improve our ability to respond to disease. The sooner we know that a condition exists, the sooner we can begin treating it, thereby increasing the odds of curing it or managing it to maintain a higher quality of life for patients.
Conventional medication is often consumed in the form of a pill or injected directly into the bloodstream intravenously. Though the latter is more direct than the former, both carry the drug throughout the body, which can oftentimes translate into undesired side effects as it interacts with parts of the body it was not intended to. By employing smarter technology, physicians can improve the accuracy with which medicines are delivered to target specific parts of the body and the diseases affecting them.
For example, researchers at the Massachusetts Institute of Technology have developed a means of delivering as little as 1 cubic milliliter of medicine to specific regions of the brain without affecting nearby neurocircuitry. The system relies on a series of miniaturized tubes known as cannulas that are roughly the diameter of a single human hair, which are then fitted into a needle and surgically implanted into the brain. These cannulas are then connected to small pumps that can be inserted under the skin, and these pumps can then send very small doses of medicine directly into targeted parts of the brain.
To test the concept, the team at MIT conducted an experiment that involved inducing symptoms associated with Parkinson’s disease in a rat. Previous studies have indicated that the drug muscimol can produce these symptoms when the drug interacts with the substantia nigra, a region of the brain located deep in the basal ganglia that controls movement. The researchers were not only able to simulate these symptoms by introducing the drug to this region of the rat’s brain; they were also able to halt them by using the device to wash the drug away with a saline solution. The study provides proof-of-concept, though it has yet to be used on human subjects.
This kind of device could be used to treat numerous conditions and diseases, among them Parkinson’s disease, Alzheimer’s disease, and perhaps even behavioral neurological diseases like obsessive compulsive disorder and addiction. “We believe this tiny microfabricated device could have tremendous impact in understanding brain diseases, as well as providing new ways of delivering biopharmaceuticals and performing biosensing in the brain,” said Robert Langer, one of the paper’s lead authors.
Similarly, nanomedicines that have been designed by researchers based at the University of Tokyo use gene therapy to fight cancer. Researchers have understood that gene therapy known as small interfering RNA (siRNA) does have the potential to disrupt the growth of cancerous tumors because these medicines bind to the malfunctioning genes and deactivate them. However, siRNA is extremely fragile and often breaks down when trying to pass through barriers to organs like the brain or the pancreas. By designing what is known as a Y-shaped block catiomer only 18 nanometers wide, the team in Tokyo were able to ensure that the siRNA could pass through these barriers and target the cancerous tissues.
Though these technologies are still in their infancy, such major breakthroughs demonstrate how greater precision in targeting diseases may help reduce side effects associated with some medications or better target the parts of the body afflicted with the disease.
On top of improving diagnostic tests and targeting specific parts of the body or brain, precision medicine is also capable of devising medicines that are made specifically for individual patients based on their genetics. Computers of almost unimaginable power can now perform DNA sequencing in a fraction of the time they were able to just a few years ago, and expected advances in quantum computing will soon cut down the time and money it takes to do so even more. To put this in perspective, it took 13 years and almost $1 billion to complete the Human Genome Project. Following the conclusion of the project in 2003, it was heralded as one of the most remarkable scientific achievements in human history. Today, sequencing costs around $1,000 and can be completed in a day.
This could have a major impact on our ability to create custom medicines to fight specific diseases. The technology may also create more effective treatments for certain types of mental illness, as researchers have found that some of these conditions, such as bipolar disorder and schizophrenia, oftentimes have similar genetic risk factors. By focusing on how specific genes impact the inner workings of the brain, researchers may be able to develop a means of preventing these disorders from developing. Though no medicines to treat mental illness using this technology have been developed at this time, it remains a promising possibility.
This is not the case with cancer research. Sequencing has already produced results, and one story sheds light on how revolutionary this technology can be. Judy Perkins had been diagnosed with Stage 4 breast cancer. Her prognosis was grim, as the cancer was resistant to conventional drugs, when she enrolled in an experimental treatment using immunotherapy that was being pioneered by a team at the National Cancer Institute. Led by Steven Rosenburg, the therapy involved sequencing the DNA of Perkins’ tumor. They then isolated Perkins’ own cancer-fighting immune cells (lymphocytes), found that they attacked the genetic mutations that had given rise to the tumor, cultured those same immune cells, and then reintroduced them to Perkins’ body. These cells then destroyed the cancer and Perkins is now cancer-free.
As more advances within the field of precision medicine take place, the number of success stories like Perkins’ is only expected to increase.
Dr. Ahmad reports no conflict of interest. He is not a speaker, advisor, or consultant and has no financial or commercial relationship with any biopharmaceutical entity whose product/device may have been mentioned in this article.