More than a hundred drugs have been approved for the treatment of cancer, but the ability to predict which of them will help a particular patient is really not an exact science. A new implantable device developed at the Massachusetts Institute of Technology may change that
![Chemical engineers from the Massachusetts Institute of Technology (MIT) have developed an implantable device capable of injecting many drugs into the body at the same time, which could help them identify the most effective drugs. [Courtesy of Eric Smith]](https://www.hayadan.org.il/images/content3/2015/05/MIT-Personalized-Med-1_0-500x333.jpg)
More than a hundred drugs have been approved for the treatment of cancer, but the ability to predict which of them will help a particular patient is really not an exact science. A new implantable device developed at the Massachusetts Institute of Technology may change that.
A new device developed at the Massachusetts Institute of Technology (MIT) may improve the ability to choose the most suitable drug for each and every patient. The implanted device, the size of a grain of rice, is able to inject low doses of up to 30 different drugs into the body. After inserting it into the tumor and waiting long enough for the drugs to reach the infected tissue, the researchers can measure how effective each of them is in destroying the patient's cancer cells.
Such a device could significantly reduce the uncertainty involved in choosing the appropriate treatment against cancer based on hypotheses alone, says researcher Oliver Jonas. The findings of the study were published in the scientific journal Science Translational Medicine.
"Our device can be used to examine the patient's response to the drugs available to us, and to choose the one that works most effectively," he adds and says. Most of the drugs commonly used to treat cancer work by causing damage to DNA or actually by interfering with cell functions. Recently, scientists have also succeeded in developing more targeted drugs designed to eliminate cancer cells with a specific genetic mutation. At the same time, it is still difficult to predict which of the drugs will be the most effective for a particular patient.
In some cases, doctors remove cancer cells from the patient, grow them in a petri dish and treat them with different drugs in order to determine which one is the most effective. At the same time, this process takes the cells out of their natural environment, a fact that can significantly affect the true response of the cells to treatment with these drugs. "The approach we thought would be good is to simply put the laboratory inside the patient," explains the lead researcher. "The procedure is safe and all sensitivity tests can be performed in the natural environment of the cells."
The device, which consists of a crystalline and hard polymer, can be implanted inside the patient's tumor with the help of a biopsy needle. After the implantation procedure, the drugs penetrate to a depth of 300-200 microns into the tumor but do not interfere with each other. Any type of drug can be filled into the reservoir in the device, and the researchers can adjust the dose of the drug so that it is similar to the dose that would be received if the drug was given in the form of an intravenous injection. After a day's exposure to the drug, the implant is removed from the body, along with a small sample of the tumor tissue surrounding the implant, and the researchers can examine the effects of the various drugs by spreading the tissue sample and staining it with antibodies that can detect markers of cell death. In order to test the effectiveness of the device, the researchers implanted it in a mouse grown with human tumors of the prostate cancer, breast cancer and skin cancer types.
It is known that these tumors have different sensitivity to different anti-cancer drugs, and the results of the researchers did confirm this. The researchers then tested the device with a type of breast cancer known as 'triple negative', a type that lacks the three most common breast cancer markers: estrogen receptor, progesterone receptor and Her2. This type of cancer is particularly aggressive and none of the drugs used against it today focus on a specific genetic marker. With the help of the device, the researchers found that tumors of this type react differently to five of the most common drugs for treatment. The most effective drug was paclitaxel, followed by doxorubicin, cisplatin, gemcitabine, and lafatinib. The results were the same even when the transfer of these drugs was carried out through an intravenous injection, a finding that suggests that the device is indeed an accurate predictor of drug sensitivity.
As part of this study, the researchers compared the effectiveness of each of the drugs separately, but the device is also capable of being used to test different drug combinations by introducing two or more drugs into the same pool, explains the lead researcher. "The device can help us identify the best chemotherapeutic substances or combinations for each and every tumor before starting to systematically administer the drug - this is in contrast to the existing method that is based on statistical data of a collection of patients. Such a solution has been the goal of many oncologists who have been pursuing it for many years and is an important step forward towards the scientific goal of developing cancer treatment based on accurate real data, and not just statistical data," explains the lead researcher. The researchers are now working on ways to make it easier to read the results of the device while it is inside the patient, which will help them get the results at a faster rate. They also intend to launch a clinical trial in breast cancer patients next year.
Another possible application of the new device could be in directing the development and testing of new drugs against cancer. Researchers will be able to create several different versions of effective compounds and test them all at once in a limited trial of human patients, which will allow them to choose the best drug with which to proceed to larger clinical trials.
