J Cancer 2020; 11(8):2192-2200. doi:10.7150/jca.39579 This issue
1. Department of Nuclear Medicine and Institute of Anesthesiology and Pain, Taihe Hospital, Hubei University of Medicine, Shiyan, 442000, China.
2. Health management center, Taihe Hospital, Hubei University of Medicine, Shiyan, 442000, China.
3. Postgraduate Training Base of Taihe Hospital, Jinzhou Medical University, Jinzhou, 121000, China.
4. Hubei Key Laboratory of WudangLocal Chinese Medicine Research, Shiyan, 442000, China.
5. Hubei Key Laboratory of Embryonic Stem Cell Research, Shiyan, 442000, China.
* These authors contributed equally to this work.
Background: To evaluate the feasibility of a self-complementing recombinant adeno-associated virus 3 (scrAAV3) vector targeting liver cancer and non-invasively monitor gene therapy of liver cancer.
Materials and methods: An scrAAV3-HSV1-TK-kallistatin (ATK) gene drug was constructed, which contained the herpes virus thymidine kinase (HSV1-TK) reporter gene and human endogenous angiogenesis inhibitor (kallistatin) gene for non-invasive imaging of gene expression. Subcutaneous xenografted tumors of hepatoma in nude mice were generated for positron emission tomography/computed tomography (PET/CT) imaging. The ATK group was injected with the ATK gene through the tail vein, and an imaging agent was injected 2 weeks later. PET/CT imaging was performed at 1 hour after injection of the imaging agent. The control group was injected with phosphate-buffered saline at the same volume as the ATK gene drug. HE staining is used for pathological observation of tumor sections. HSV1-TK and kallistatin expression was identified by immunofluorescence, real-time quantitative PCR, and western blotting.
Results: Radioactivity on PET/CT images was significantly higher in the ATK group compared with the control group. 18F-FHBG uptake values of left forelegs in ATK and control groups were 0.591±0.151% and 0.017 ± 0.011% ID/g (n=5), respectively (P<0.05). After injection of the ATK gene drug, mRNA and protein expression of HSV1-TK and kallistatin in subcutaneous xenograft tumors was detected successfully. In vitro analysis demonstrated significant differences in the expression of HSV1-TK and kallistatin between ATK and control groups (P<0.05).
Conclusions: The scrAAV3 vector has a strong liver cancer-targeting ability, and the ATK gene drug can be used for targeted and non-invasive monitoring of liver cancer gene therapy.
Keywords: Self-complementary recombinant adeno-associated virus 3, Molecular imaging, Targeted therapy, Liver cancer