Hepatocellular carcinoma (HCC), the third most common cause of cancer-related deaths worldwide, most
often develops in patients with underlying liver cirrhosis or chronic injury secondary to alcohol abuse, non-
alcoholic fatty liver disease, or viral hepatitis infections. Cirrhosis from any cause is a well-established risk
factor for HCC. The poor prognosis of HCC is due to the fact that diagnosis is often made at a late stage in
disease development. The earlier detection of HCC is necessary towards reducing the high HCC mortality
rates since those with early stage disease have multiple, potentially curative, treatment options available.
However, current surveillance regimens with abdominal imaging and serum biomarkers (e.g., AFP) have poor
sensitivity for diagnosing HCC at an early-stage. Therefore, biomarkers that sensitively distinguish early-stage
HCC from liver cirrhosis are desperately needed.
Extracellular vesicles (EVs) are a heterogeneous group of phospholipid bilayer-enclosed particles known to
contain cell-type-specific “cargo,” including RNA, DNA, and protein. Cargo profiling of tumor-derived EVs is an
emerging liquid biopsy strategy for non-invasive cancer diagnosis and treatment monitoring. Our joint research
team at UCLA has recently developed a new type of “NanoVilli Chip” capable of highly efficient isolation and
characterization of tumor-derived EVs from HCC patients. Exploring the use of NanoVilli Chips for cargo
profiling of HCC-derived EVs holds great promise as a novel biomarker for detecting early-stage HCC
noninvasively. Conventional methods for isolating total EVs, such as ultracentrifugation, filtration, and
precipitation, are incapable of discriminating tumor-derived EVs from non-tumor-derived EVs. To address this
unmet need, our project team will develop “NanoVilli Chips” based on biomimetic nanostructures and specific
immunoaffinity-mediated capturing for HCC-derived EVs. HCC-specific multi-marker capture cocktails
(targeting ASGPR, GPC3, and EpCAM) will be grafted onto silicon nanowires (SiNWS) embedded in the chips.
When plasma samples approach the SiNWS, specific interactions (between antigens located on the surfaces
of tumor-derived EVs and corresponding antibodies grafted on the substrate) lead to selective immobilization
of HCC-derived EVs, with dramatically improved sensitivity and specificity. Further, by incorporating Droplet
Digital PCR (ddPCR) technology, the HCC-derived EVs captured on the NanoVilli Chips can be characterized
by quantifying a panel of 10 well-validated HCC-specific mRNA markers. The proposed research will conduct
an exploratory development of NanoVilli Chips for HCC-derived EVs, and an initial clinical validation of
NanoVilli Chips using HCC and liver cirrhosis blood samples. Our long-term goal is to explore the use of
NanoVilli Chips coated with HCC-associated multi-marker capture cocktails for capturing HCC-derived EVs,
allowing for quantification of HCC-specific mRNA signature to augment current HCC early diagnostic
algorithms.