Molecular Machines May Lead to Early Cancer Detection, Targeted Therapies

Molecular machines, referred to as nanomachines, could be the future of disease detection and drug delivery, according to a study published by Nature Communications. This technology could lead to earlier diagnoses and more targeted treatments.

In the study, the authors recount the development of DNA motors that are placed inside living cells. The process shows how DNA motors can be implemented to manage biological functions in cells.

"This is really big because of the diverse potential applications," said researcher Chris Le, PhD. "One outcome of this will be to provide better and earlier disease detection. Another is the controllable release of targeted drug molecules within patients, resulting in fewer side effects."

The authors created the nanomachine from compartments made of DNA enzyme molecules and substrates.

“This nanomachine has the required fuels, DNA tracks, and a molecular switch," said researcher Hongquan Zhang, PhD.

In the study, the investigators programmed the nanomachines to detect microRNA in breast cancer cells. Upon contact with the specific molecule, the DNA motor was activated and produced florescence, according to the study.

Due to the florescent reaction, the authors were able to determine which cells were cancerous. This method shows significant promise for early diagnosis, and may help physicians treat cancer with higher success rates.

"We want to be able to detect cancer or disease markers in very minute amounts before the disease gets out of hand. That way physicians can attack it very early," Dr Le said. "The trace amount of the target molecules that may be missed by other techniques can now be detected with this one."

The investigators also believe that DNA motors can be used for more targeted drug delivery. While conventional targeted drug therapy delivers the treatment to the site of action, it can also impact the surrounding healthy tissues, and elicit side effects.

However, with the nanomachines, the authors believe that the drug payload can be delivered to a specific site, and released only when triggered by certain disease-specific molecules, according to the study.

Although only the breast cancer maker was used in the study, further testing should be conducted using other biomarkers, and to determine its capabilities for drug delivery.

"You still have some drug molecules going to the normal cells -- you can't avoid that," Dr Le said. "Using the DNA motor, we hope to deliver the drug into the cells in an inactive form. Only when the DNA motor encounters the targeted molecules can the drug then be released to be active."