MIT scientists develop ‘vape’ test to detect lung cancer sooner

By James Gamble via SWNS

A new "vape type" inhalable lung cancer test could help doctors catch the disease earlier.

The test delivers sensors into the lungs through an inhaler or nebulizer and returns results after a simple urine sample.

It could provide a more accessible alternative for those at risk of lung cancer.

Tests on mice showed the test to be accurate, fast and far less invasive than current CT scans which are unavailable to many.

The American researchers behind the clever new test say it could have a huge impact in providing early diagnoses and helping patients get the curative surgery or lifesaving medicines they require.

To diagnose lung cancer as early as possible, the US Preventive Services Task Force recommends that heavy smokers over the age of 50 undergo annual low-dose computed tomography (CT) scans.

However, many in this target group from low and middle-income countries are unable to receive these scans, which can also be invasive and return high false-positive results.

Scientists from the Massachusetts Institute of Technology (MIT) have been working over the past decade to develop nanosensors to diagnose cancer and other diseases.

In this latest study, published in the journal Science Advances, the researchers explored the possibility of using these sensors to develop a more accessible alternative to CT screening to detect lung cancer.

The sensors consist of polymer nanoparticles coated with a "reporter," such as a DNA barcode, which is separated from the particle when the sensor encounters enzymes called proteases, which are often overactive in tumors.

After passing through the lungs, these reporters eventually exit the body in the urine.

Previous versions of the sensors which targeted cancers in other sites such as the live and ovaries were designed to be delivered into the veins of patients.

But for their lung cancer test, the researchers wanted to create a version that could instead be inhaled, which would make it easier to deploy in settings with lower resources.

Dr. Qian Zhong, a research scientist at MIT, explained: "When we developed this technology, our goal was to provide a method that can detect cancer with high specificity and sensitivity, and also lower the threshold for accessibility so that, hopefully, we can improve the resource disparity and inequity in early detection of lung cancer."

To this end, the research team created two formulations of their particles: an "aerosolized" solution delivered using a nebulizer - a device producing a fine liquid mist of medicine - and a dry powder delivered using an inhaler.

Once the nanoparticles reach the lungs they are absorbed into the tissue, where they encounter any proteases present.

Human cells can express hundreds of different proteases - some of which are overactive in tumors where they help cancer cells escape their origin locations by cutting through proteins of the extracellular matrix.

These cancerous proteases sever DNA barcodes from the sensors, allowing them to circulate in the bloodstream until they are released in the urine.

Previous versions of this technology used mass spectrometry, an analytical tool for measuring the mass-to-charge ratio of one or more molecules present in a sample, to analyze urine samples and detect DNA barcodes, but this requires equipment that may be unavailable in low-resource areas.

So, for their latest version of the test, the researchers created a lateral flow test, which enables the barcodes to be detected using a simple paper strip.

These strips were designed to detect up to four different DNA barcodes, each indicating the presence of a different protease.

No pre-treatment or processing of the urine sample is needed and results can be read around just 20 minutes after the sample is obtained.

Dr. Sangeeta Bhatia, a Professor of Health Sciences and Technology and Electrical Engineering and Computer Science at MIT, spoke of the importance of developing fast, simple and cheap tests to screen those to whom CT scans are not readily available.

The senior author of the study explained: "Around the world, cancer is going to become more and more prevalent in low- and middle-income countries.

"The epidemiology of lung cancer globally is that it’s driven by pollution and smoking, so we know that those are settings where accessibility to this kind of technology could have a big impact.

“We were really pushing this [test] to be point-of-care available in a low-resource setting, so the idea was to not do any sample processing, not do any amplification, just to be able to put the sample right on the paper and read it out in 20 minutes."

The researchers tested their new device on mice genetically engineered to develop lung tumors similar to those seen in humans.

The sensors were delivered 7.5 weeks after tumors began to form - a time that would correlate with stage one or two cancer in humans.

In their first set of experiments, the researchers measured the levels of 20 different sensors designed to detect different proteases.

Using a machine learning algorithm to analyze the results, the researchers identified a combination of just four sensors that were predicted to give accurate diagnostic results.

They then tested that combination in the mouse model and found that it could accurately detect early-stage lung tumors.

The research team admit that more sensors may be needed to make an accurate diagnosis, though this could be achieved by using multiple paper strips, each detecting four different DNA barcodes.

Analysis of human biopsy samples is now planned to observe whether the sensor panels would also work to accurately detect human cancers, with hopes of clinical trials in human patients down the line.

A company called Sunbird Bio has already run phase one trials on a similar sensor developed by Dr. Bhatia’s lab for use in diagnosing liver cancer and a form of hepatitis known as nonalcoholic steatohepatitis (NASH).

Dr. Bhatia emphasized the dramatic impact the new accessible test could have in parts of the world where access to CT scanning is limited.

She added: "The idea would be you come in and then you get an answer about whether you need a follow-up test or not.

"We could get patients who have early lesions into the system so that they could get curative surgery or lifesaving medicines."