Abstract:
Hepatocellular carcinoma (HCC) accounts for the third deadly malignancies worldwide, and portal invasion is an early sign of advanced stage. Our previous studies have demonstrated that the high expression of sonic hedgehog ligand (SHh) is closely correlated to the metastasis, drug resistance and poor prognosis of HCC. Therefore, sensitive, specific and efficient detection methods for SHh are needed for the early diagnosis and assessment of prognosis. Herein, an aptamer, AP32 that specifically binds to SHh was obtained by SELEX technology with further optimization. Animal experiments confirmed that AP32 has the potential to be an imaging probe for Huh-7 cell-derived xenograft. The interaction mode in 3-dimensional configuration between the aptamer and SHh was established by molecular simulation and confirmed by mutations at key sites of the aptamer. An aptasensor-based assay was successfully developed by conjugating Texas-Red-labelled AP32 to microbeads, and was used to analyse SHh content in hepatoma cell lysates, serum and HCC specimens. The method exhibited a broad detection range from 0.07 to 62.5 nM with a low detection limit of 69 pM, and a recovery rate of 104.6 ± 3.9% in serum. When the assay was used to measure SHh content in tissue lysates, the results demonstrated that it possessed 57.1% positivity, 100% specificity in distinguishing 28 HCC specimens from normal tissues, and was compensatory for detection of HCC in α-fetoprotein (AFP)-negative cases. Moreover, elevated SHh levels are indicative of portal vein invasion at 77.8% positive rate. This novel aptasensor-based SHh assay may offer a reliable means in predicting early metastasis and poor prognosis in HCC and other malignancies.
Biography:
Dr. Jian Wu was trained as a specialist in Gastroenterology and Hepatolgoy in Southeast University Medical College, Nanjing, China, before he obtained a medicine doctorate degree (PhD) from Umeå University, Sweden. After that, he was employed as a post-doctoral scientist in Thomas Jefferson University, Philadelphia, PA, USA, and received the National Research Service Award. Thereafter, Dr. Wu was employed as assistant, associate and full professor in the Dept. of Internal Medicine, Division of Gastroenterology & Hepatology, University of California, Davis Medical Center, Sacramento, CA, USA for 15 years. He was re-located to Fudan University Shanghai Medical College in 2013 as a professor in School of Basic Medical Sciences, Fudan University and has a joint professorship with the Department of Gastroenterology and Hepatology, Zhongshan Hospital of Fudan University. Dr. Wu was designated as a “Liver Scholar” by the American Liver Foundation and the American Association for the Study of Liver Diseases (AASLD), and was recognized as a Fellow of ASSLD in 2017. He has a track of record for more than 145 publications in highly-ranked professional journals, such as Gastroenterology, Hepatology, Journal of Hepatology, Cancer Research, Biosensors & Bioelectronics, Journal of Nanobiotechnologies, etc. with a citation record of over 8000. He has been an external referrer for various governmental funding agencies, such as INSERM in France, RCUK in UK, STW in Netherlands, NIH in the US, and the Natural Science foundation of China (NSFC). He serves in a review panel for specially emphasized proposals, awards of scientific advances of the Ministry of Education, Changjiang Scholars, key projects from Ministry of Sciences and Technologies of China. Currently, He is well funded by the NSFC and the Ministry of Sciences and Technologies of China for projects dealing with liver metabolic abnormalities, chronic inflammation and malignant transformation, as well as regenerative cure for hepatic failure.
