Seek and destroy: targeted adeno-associated viruses for gene delivery to hepatocellular carcinoma

Figures & data

Figure 1. Strategies used for gene therapy of HCC. (A) Restoration of tumor suppressor genes or inhibition of oncogenes may restore normal functioning of the tumor cells. (B) Direct administration of recombinant rAAV expressing toxins or apoptotic factors like TRAIL can lead to tumor cytotoxicity and/or apoptosis. (C) GDEPT is a two-step process to induce tumor cell death. Tumor cells are first transduced with rAAV expressing suicide gene followed by systemic administration of prodrug which is metabolized by the transduced cell into a toxic metabolite. (D) Anti-angiogenic gene therapy using AAV vectors can inhibit formation of new blood vessels, ultimately leading to tumor apoptosis and inhibition of metastasis. (E) Delivery of cytokines and immunomodulatory genes either using AAV vector or immune cells transduced with rAAV vectors harboring cytokines (adoptive immunotherapy) to tumor cells triggers an anti-tumor immune response via recruitment of immune cells.

Table 1. Gene therapy studies for HCC using AAV based vectors.

Therapeutic gene/intervention	Strategy/combination	Target	Results/comments	Ref.
HSV-TK	Suicide gene therapy	HCC cell lines	Selective killing of HCC cells using liver-specific promoter and tumor specific enhancer	(Su et al., 1996)
HSV-TK	Suicide gene therapy	Mouse model	Reduction of tumor growth and observation of by stander effect	(Su et al., 1997)
HSV-TK	Suicide gene therapy	HCC cell lines/mouse model	Use of a liver specific promoter combined with posttranscriptional regulation to achieve HCC-specific HSV-tk expression; reduction in tumor growth and low toxicity	(Della Peruta et al., 2015)
p53	Combination of rAAV-p53 with chemotherapy	HCC cell lines	Increased permissiveness of HCC cells following doxorubicin treatment; synergistic cytotoxic effects were seen	(Chen et al., 2008)
p53/HGFK1	Combination of rAAV-HGFK1 with rAdV-p53	HCC cell lines, mouse and rat models	Decreased proliferation of HCC cells in vitro; prolonged survival in animal models by induction of tumor cell death and antiangiogenesis	(Shen et al., 2008a)
HGFK1	Anti-angiogenesis rAAV-HGFK1	HCC cell lines and rat HCC model	Increased survival, tumor cell death by induction of apoptosis and antiangiogenesis, prevention of metastasis	(Shen et al., 2008b)
Angiostatin	Anti-angiogenesis rAAV-angiostatin	Mouse model	Stable, high-level expression of angiostatin for at least six months; inhibition of metastasis and extensive tumor apoptosis; increased survival	(Xu et al., 2003)
Endostatin	Anti-angiogenesis (rAAV-endostatin) combined with chemotherapy	HCC cell lines, mouse model	Increased transduction and high level of endostatin expression when combined with etoposide as compared to control or monotherapy groups both in vitro and in vivo; antitumor and antiangiogenic responses were observed along with increased survival in animal model	(Hong et al., 2004)
Kallistatin	Anti-angiogenesis	HCC cell lines, mouse models	Suppression of tumor cell proliferation and apoptosis via inhibition of angiogenesis	(Tse et al., 2008)
Kringle domains of apo(a)	Anti-angiogenesis	HCC cell lines, mouse model	Inhibition of angiogenesis, induction of tumor apoptosis and prolonged survival in animal model	(Lee et al., 2006)
TRAIL	Induction of tumor apoptosis	Mouse model	Prolonged survival; induction of tumor apoptosis and prevention of metastasis	(Ma et al., 2005a)
TRAIL/insulin	Induction of apoptosis	Mouse model	Oral administration of rAAV-TRAIL fused to secretion signal peptide of insulin demonstrated reduced tumor growth and non-toxicity to normal hepatocytes	(Ma et al., 2005b)
TRAIL	Induction of apoptosis	HCC cell lines, mouse model	TRAIL under the control of hTERT promoter (rAAV-hTERT-TRAIL) lead to cancer specific TRAIL expression and tumor apoptosis	(Wang et al., 2008)
TRAIL	Induction of apoptosis combined with chemotherapy	HCC cell lines, mouse model	Systemic administration of rAAV-hTERT-TRAIL lead to tumor-specific TRAIL expression; combinatorial therapy with 5-FU lead to enhanced tumor cell death	(Zhang et al., 2008)
TRAIL	Induction of apoptosis combined with chemotherapy	HCC cell lines, mouse model	Enhanced TRAIL expression was observed in tumor cells following treatment with cisplatin. Increased tumor cell death and apoptosis was observed in vivo	(Wang et al., 2010)
miR26a	Induction of tumor apoptosis	HCC cell lines, mouse model	Systemic administration of rAAV-miR26a lead to tumor specific induction of apoptosis, inhibition of tumor proliferation and no toxicity	(Kota et al., 2009)
Apoptotin/IL24	Induction of apoptosis combined with cytokine therapy	HepG2, mouse model	Synergistic antitumor effects of apoptotin and IL24 was observed by induction of apoptosis	(Yuan et al., 2013)
Secondary lymphoid tissue chemokine (SLC)	Genetic immune therapy	Hepa1-6, mouse model	Hepa1-6 pretreated with rAAV-SLC was injected in mouse model; delayed tumor progression and strong anti-tumor immune response by infiltration of DCs and activated T-cells were observed	(Liang et al., 2007)
IL15	Genetic immune therapy	Mouse model	Prolonged survival; significant antitumor response mainly dependent on NK cells; no observable liver toxicity	(Chang et al., 2010)
IL12	Genetic immune therapy	Mouse model	Increased survival, inhibition of metastasis, decrease in tumor vessel density and antitumor response by infiltration of NK cells, activated T cells and NKT cells. No such effects were observed with IL23 and IL27	(Lo et al., 2010)
IL12/IFN gamma	Genetic immune therapy	Mouse model	Liver specific, tet-on inducible AAV system with liver-specific promoter was used to express IL12 in vivo. Prolonged survival, significant antitumor response and memory T cell response was observed	(Vanrell et al., 2011)
AFP	Ex vivo gene therapy	HepG2 and BEL7402	DCs generated from mononuclear cells transduced with rAAV-AFP and cultured along with GM-CSF and IL4 displayed enhanced ability to activate cytotoxic T-cells	(Du & Yu, 2011)
LacZ (reporter)	Evaluation of the effects of chemo and radiotherapy on rAAV tumor transduction	HCC cell lines, mouse and rat models	Enhanced transduction was observed with radio and chemotherapy in vitro, however, only radiation was able to show similar effects in animal models	(Peng et al., 2000)

Figure 2. Capsid modification of AAV by insertion of HCC-binding ligands. Insertion of HCC-binding peptides at sites of AAV capsid which tolerate insertions without affecting viral life cycle can change the natural tropism of the vector and retarget it to HCC.

Figure 3. Transcriptional targeting with HCC-specific promoters. Tumor specific promoters are selectively active in cancer cells and are able to regulate the expression of therapeutic gene in a cancer specific manner. The identification and use of HCC-specific promoters could minimize off-target effects by limiting the expression of therapeutic gene in HCC.

Su H, Chang JC, Xu SM, Kan YW. (1996). Selective killing of AFP-positive hepatocellular carcinoma cells by adeno-associated virus transfer of the herpes simplex virus thymidine kinase gene. Hum Gene Ther 7:463–70

 PubMed Web of Science ®Google Scholar

Su H, Lu R, Chang JC, Kan YW. (1997). Tissue-specific expression of herpes simplex virus thymidine kinase gene delivered by adeno-associated virus inhibits the growth of human hepatocellular carcinoma in athymic mice. Proc Natl Acad Sci USA 94:13891–6

 PubMed Web of Science ®Google Scholar

Della Peruta M, Badar A, Rosales C, et al. (2015). Preferential targeting of disseminated liver tumors using a recombinant adeno-associated viral vector. Hum Gene Ther 26:94–103

 PubMed Web of Science ®Google Scholar

Chen CA, Lo CK, Lin BL, et al. (2008). Application of doxorubicin-induced rAAV2-p53 gene delivery in combined chemotherapy and gene therapy for hepatocellular carcinoma. Cancer Biol Ther 7:303–9

 PubMed Web of Science ®Google Scholar

Shen Z, Wong OG, Yao RY, et al. (2008a). A novel and effective hepatocyte growth factor kringle 1 domain and p53 cocktail viral gene therapy for the treatment of hepatocellular carcinoma. Cancer Lett 272:268–76

 PubMed Web of Science ®Google Scholar

Shen Z, Yang ZF, Gao Y, et al. (2008b). The kringle 1 domain of hepatocyte growth factor has antiangiogenic and antitumor cell effects on hepatocellular carcinoma. Cancer Res 68:404–14

 PubMed Web of Science ®Google Scholar

Xu R, Sun X, Tse LY, et al. (2003). Long-term expression of angiostatin suppresses metastatic liver cancer in mice. Hepatology 37:1451–60

 PubMed Web of Science ®Google Scholar

Hong SY, Lee MH, Kim KS, et al. (2004). Adeno-associated virus mediated endostatin gene therapy in combination with topoisomerase inhibitor effectively controls liver tumor in mouse model. World J Gastroenterol 10:1191–7

 PubMed Web of Science ®Google Scholar

Tse LY, Sun X, Jiang H, et al. (2008). Adeno-associated virus-mediated expression of kallistatin suppresses local and remote hepatocellular carcinomas. J Gene Med 10:508–17

 PubMed Web of Science ®Google Scholar

Lee K, Yun ST, Kim YG, et al. (2006). Adeno-associated virus-mediated expression of apolipoprotein (a) kringles suppresses hepatocellular carcinoma growth in mice. Hepatology 43:1063–73

 PubMed Web of Science ®Google Scholar

Ma H, Liu Y, Liu S, et al. (2005a). Recombinant adeno-associated virus-mediated TRAIL gene therapy suppresses liver metastatic tumors. Int J Cancer 116:314–21

 PubMed Web of Science ®Google Scholar

Ma H, Liu Y, Liu S, et al. (2005b). Oral adeno-associated virus-sTRAIL gene therapy suppresses human hepatocellular carcinoma growth in mice. Hepatology 42:1355–63

 PubMed Web of Science ®Google Scholar

Wang Y, Huang F, Cai H, et al. (2008). Potent antitumor effect of TRAIL mediated by a novel adeno-associated viral vector targeting to telomerase activity for human hepatocellular carcinoma. J Gene Med 10:518–26

 PubMed Web of Science ®Google Scholar

Zhang Y, Ma H, Zhang J, et al. (2008). AAV-mediated TRAIL gene expression driven by hTERT promoter suppressed human hepatocellular carcinoma growth in mice. Life Sci 82:1154–61

 PubMed Web of Science ®Google Scholar

Wang Y, Huang F, Cai H, et al. (2010). The efficacy of combination therapy using adeno-associated virus-TRAIL targeting to telomerase activity and cisplatin in a mice model of hepatocellular carcinoma. J Cancer Res Clin Oncol 136:1827–37

 PubMed Web of Science ®Google Scholar

Kota J, Chivukula RR, O'donnell KA, et al. (2009). Therapeutic microRNA delivery suppresses tumorigenesis in a murine liver cancer model. Cell 137:1005–17

 PubMed Web of Science ®Google Scholar

Yuan L, Zhao H, Zhang L, Liu X. (2013). The efficacy of combination therapy using adeno-associated virus-mediated co-expression of apoptin and interleukin-24 on hepatocellular carcinoma. Tumor Biol 34:3027–34

 PubMed Web of Science ®Google Scholar

Liang CM, Zhong CP, Sun RX, et al. (2007). Local expression of secondary lymphoid tissue chemokine delivered by adeno-associated virus within the tumor bed stimulates strong anti-liver tumor immunity. J Virol 81:9502–11

 PubMed Web of Science ®Google Scholar

Chang CM, Lo CH, Shih YM, et al. (2010). Treatment of hepatocellular carcinoma with adeno-associated virus encoding interleukin-15 superagonist. Hum Gene Ther 21:611–21

 PubMed Web of Science ®Google Scholar

Lo CH, Chang CM, Tang SW, et al. (2010). Differential antitumor effect of interleukin-12 family cytokines on orthotopic hepatocellular carcinoma. J Gene Med 12:423–34

 PubMed Web of Science ®Google Scholar

Vanrell L, Di Scala M, Blanco L, et al. (2011). Development of a liver-specific Tet-on inducible system for AAV vectors and its application in the treatment of liver cancer. Mol Ther 19:1245–53

 PubMed Web of Science ®Google Scholar

Du WZ, Yu TX. (2011). Generation of antitumor response against hepatocellular carcinoma by in vitro transduction of dendritic cells with adeno-associated virus expressing α-fetoprotein. Zhonghua Yi Xue Za Zhi 91:2077–80

 PubMedGoogle Scholar

Peng D, Qian C, Sun Y, et al. (2000). Transduction of hepatocellular carcinoma (HCC) using recombinant adeno-associated virus (rAAV): in vitro and in vivo effects of genotoxic agents. J Hepatol 32:975–85

 PubMed Web of Science ®Google Scholar