Could detecting cancer one day be as easy as taking a blood test? Wei-Chuan Shih, a University of Houston researcher and Cullen College of Engineering professor of electrical and computer engineering, has reported a 98.7-percent rate of accuracy for a method pioneered by his lab to identify cancers at their earliest stages.
The technology combines Shih’s own PANORAMA (PlAsmonic NanO-apeRture lAbel-free iMAging) with fluorescent imaging to view nanometer-sized membrane sacs, called extracellular vesicles or EVs. EVs carry different types of cargo, including proteins, nucleic acids and metabolites, throughout the bloodstream.
“We observed differences in small EV numbers and cargo in samples taken from healthy people versus people with cancer and are able to differentiate these two populations based on our analysis of the small EVs,” reports Shih, in Nature Communications Medicine. “The findings came from combining two imaging methods – our previously developed method PANORAMA and imaging of fluorescence emitted by small EVs—to visualize and count small EVs, determine their size and analyze their cargo.”
Shih introduced PANORAMA in 2020. The technology uses a glass side covered with gold nano discs that allows users to monitor changes in the transmission of light as well as determine the characteristics of nanoparticles as small as 25 nanometers in diameter. For the new publication, Shih and his team just had to count the number of small EVs in order to detect cancer.
“Using a cutoff of 70 normalized small EV counts, all cancer samples from 205 patients were above this threshold except for one sample, and for healthy samples, from 106 healthy individuals, all but three were above this cutoff, giving a cancer detection sensitivity of 99.5% and specificity of 97.3%,” says Shih.
The team was able to report 100-percent accuracy with further testing that analyzed two independent sets of samples from stage I-IV or recurrent leiomyosarcoma/gastrointestinal stromal tumors and early-and-late-stage cholangiocarcinoma combined with healthy samples.
Shih and collaborator Steven H. Lin have founded Seek Diagnostics with the goal of commercializing the technology that they’ve innovated. In 2022, the duo joined the Texas Medical Center Innovation's cancer-focused accelerator.
Wei-Chuan Shih is a professor of electrical and computer engineering at the University of Houston's Cullen College of Engineering. Photo via UH.edu
