Cancer Targeting Gene-Viro-Therapy Research Articles

A Triple-Regulated Oncolytic Adenovirus Carrying MicroRNA-143 Exhibits Potent Antitumor Efficacy in Colorectal Cancer

The cancer-targeting gene virotherapy might be a useful strategy for the treatment of cancer, because it could combine the advantages of both gene therapy and virotherapy. This study aimed to construct a triple-regulated oncolytic adenovirus, Ad-RGD-Survivin-ZD55-miR-143, carrying the therapeutic gene miR-143 and evaluate its possible antitumor effect in colorectal cancer. We observed that miR-143 was lowly expressed in patients with colorectal cancer. The upregulation of miR-143 could inhibit cell proliferation and induce cell apoptosis by targeting KRAS in colorectal cancer cells. Then, Ad-RGD-Survivin-ZD55-miR-143 was successfully constructed in this study. Cells infected with Ad-RGD-Survivin-ZD55-miR-143 could inhibit cell proliferation, suppress cell migration and invasion, arrest cells at the G1 phase, and induce cellular apoptosis. At the same time, Ad-RGD-Survivin-ZD55-miR-143 decreased the expression of PARP-1 and KRAS protein in vitro. In a HCT116 xenograft model, intratumoral injection of Ad-RGD-Survivin-ZD55-miR-143 resulted in reduced tumor growth. Furthermore, Ad-RGD-Survivin-ZD55-miR-143 induced apoptosis and decreased the expression level of KRAS in HCT116 xenograft cells. Our results suggested that Ad-RGD-Survivin-ZD55-miR-143 produced a strong antitumor effect by targeting KRAS and that this strategy could broaden the therapeutic options for treating colorectal cancer.

Efficacy of combining ING4 and TRAIL genes in cancer-targeting gene virotherapy strategy: first evidence in preclinical hepatocellular carcinoma

Current treatments of hepatocellular carcinoma (HCC) are ineffective and unsatisfactory in many aspects. Cancer-targeting gene virotherapy using oncolytic adenoviruses (OAds) armed with anticancer genes has shown efficacy and safety in clinical trials. Nowadays, both inhibitor of growth 4 (ING4), as a multimodal tumor suppressor gene, and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), as a potent apoptosis-inducing gene, are experiencing a renaissance in cancer gene therapy. Herein we investigated the antitumor activity and safety of mono- and combined therapy with OAds armed with ING4 (Ad-ΔB/ING4) and TRAIL (Ad-ΔB/TRAIL) gene, respectively, on preclinical models of human HCC. OAd-mediated expression of ING4 or TRAIL transgene was confirmed. Ad-ΔB/TRAIL and/or Ad-ΔB/ING4 exhibited potent killing effect on human HCC cells (HuH7 and Hep3B) but not on normal liver cells. Most importantly, systemic therapy with Ad-ΔB/ING4 plus Ad-ΔB/TRAIL elicited more eradicative effect on an orthotopic mouse model of human HCC than their monotherapy, without causing obvious overlapping toxicity. Mechanistically, Ad-ΔB/ING4 and Ad-ΔB/TRAIL were remarkably cooperated to induce antitumor apoptosis and immune response, and to repress tumor angiogenesis. This is the first study showing that concomitant therapy with Ad-ΔB/ING4 and Ad-ΔB/TRAIL may provide a potential strategy for HCC therapy and merits further investigations to realize its possible clinical translation.

Targeting gene-virus-mediated manganese superoxide dismutase effectively suppresses tumor growth in hepatocellular carcinoma in vitro and in vivo.

Although the treatment methods for hepatocellular carcinoma (HCC) have made a great progress on patient survival rate and life quality, the HCC recurrence still is very high. To explore the novel effective anticancer strategies for HCC, the Cancer Targeting Gene-Viro-Therapy (CTGVT) strategy was applied through oncolytic virus-delivery antitumor gene. In this article, the dual-regulated oncolytic adenovirus Ad-AFP-E1A-E1B(Δ55kDa)-Mn-SOD (briefly named AD55-Mn-SOD) was constructed using a liver cancer-specific α-fetoprotein (AFP) promoter to control replication-essential E1A gene and deliver the novel tumor suppression gene Manganese superoxide dismutase (Mn-SOD). The results indicated that the constructed AD55-Mn-SOD exerted tumor-specific features, and induced dramatic cytotoxicity in HCC cells in vitro and suppress the HCC xenografted growth in nude mice. Moreover, the anticancer mechanism of AD55-Mn-SOD is due to the activation of caspase apoptotic pathway. These data suggested that AD55-Mn-SOD could become a potential anticancer agent for liver cancer.

Synergistic suppression effect on tumor growth of hepatocellular carcinoma by combining oncolytic adenovirus carrying XAF1 with cisplatin.

The potent anticancer efficacy of oncolytic viruses has been verified in Clinic in recent years. Cisplatin (DDP) is one of most common chemotherapeutic drugs, but is accompanied by side effects and drug resistance. Our previous studies have shown the strategy of cancer -targeting gene-viro-therapy (CTGVT) mediated by the oncolytic virus ZD55 containing the XAF1 cDNA (ZD55-XAF1), which exhibited potent antitumor effects in various tumor cells and no apparent toxicities on normal cells. In the study, the CTGVT strategy is broadened by combining DDP with ZD55-XAF1 for growth inhibition of hepatocellular carcinoma (HCC) cells. The transgenic expression was evaluated by both in vitro and in vivo experiments, and the enhanced inhibitory effect of ZD55-XAF1 combined with cisplatin was assessed in HCC cells. The cytotoxicity on normal liver cells was evaluated by MTT assay and apoptotic cell staining. Activation of caspase-9 and PARP for apoptosis was further detected by Western blot analysis. The in vivo antitumor efficacy of combination treatment with cisplatin and ZD55-XAF1 was estimated in an HCC xenograft mouse model. We found that the combination of ZD55-XAF1 and cisplatin showed enhanced inhibitory effects on the proliferation of HCC cells in vitro and tumor growth in mice. Furthermore, the combined treatment of ZD55-XAF1 and DDP decreases the chemotherapy dose needed to achieve the same inhibitory effect without overlapping toxicities on normal liver cells and induces tumor cell apoptosis via the activation of caspase-9/PARP pathway. Thus, these data suggest that the chemo-gene-viro-therapeutic strategy by combining ZD55-XAF1 and DDP reveals a novel therapeutic strategy for hepatocellular carcinoma.

Cancer targeting gene-viro-therapy for pancreatic cancer using oncolytic adenovirus ZD55-IL-24 in immune-competent mice

Cancer targeting gene-viro-therapy (CTGVT) may prove to be an effective treatment for pancreatic cancer (PC). This study was intended to explore the anti-tumor effect of ZD55-IL-24 (oncolytic adenovirus ZD55 harboring IL-24) on PC in immune-competent mice. The expression of gene harbored by oncolytic adenovirus ZD55 in PC cells was detected by reporter-gene assays. The in vitro anti PC ability of ZD55-IL-24 was tested by MTT, crystal violet staining and apoptosis assays. The in vivo anti PC effect of ZD55-IL-24 was further observed in an immune-competent mice model by detecting anti-tumor immunity and induction of apoptosis. The expression of gene harbored by ZD55 in PC cells was significantly higher than that harbored by the replicated-deficient adenovirus, and the amount of gene expression was time-dependent and dose-dependent. Both ZD55-IL-24 and ZD55 inhibited PC cells growth, but the anti-tumor effect of ZD55-IL-24 was significantly stronger than that of ZD55, and the ability of ZD55-IL-24 in inducing PC apoptosis was significantly stronger than that of ZD55. The tumor-forming rate of group ZD55-IL-24 was the lowest, and the tumor-growing rate was also significantly lower than that of group ZD55 in immune-competent PC models. Moreover, ZD55-IL-24 mediated more anti-cancer immunity effects by induction of stronger T-lymphocytes response to PC cells, higher levels of γ-IFN and IL-6 cytokines. ZD55-IL-24-mediated CTGVT could inhibit PC growth not only by inducing oncolysis and apoptosis but enhancing the anti-cancer immune effects by inducing T cell response to PC and up-regulating γ-IFN and IL-6 cytokine in immune-competent mice. This may serve as a candidate therapeutic approach for the treatment of PC.

One Potential Oncolytic Adenovirus Expressing Lipocalin-2 for Colorectal Cancer Therapy

Colorectal cancer is an aggressive malignancy with a high mortality rate; however, effective therapies are currently lacking. Cancer-targeting gene-virotherapy (CTGVT) has been proposed to be a promising strategy for cancer therapy. The purpose of this study was to investigate the antitumor activity of the oncolytic adenovirus harboring Lipocalin-2 (ZD55-Lipocalin-2, an example of CTGVT) in colorectal cancer. ZD55-Lipocalin-2 was generated by deleting E1B55-KD and inserting the Lipocalin-2 gene. Its cytopathic effects and cell growth inhibition were detected in vitro, and antitumor effects were examined in a nude mouse model of human colorectal cancer xenografts. Results showed that ZD55-Lipocalin-2 significantly inhibited the colorectal cancer growth by selective cytolysis, inducing apoptosis and decreasing the microvessel density in tumors. The anticancer potential of ZD55-Lipocalin-2 showed stronger than that of the isolated Lipocalin-2 gene therapy or isolated ZD55 oncolytic adenovirus therapy. ZD55-Lipocalin-2 may serve as a potential anticancer agent for colorectal cancer treatment.

Potent and specific antitumor effect for colorectal cancer by CEA and Rb double regulated oncolytic adenovirus harboring ST13 gene.

Cancer Targeting Gene-Viro-Therapy (CTGVT) is constructed by inserting an antitumor gene into an oncolytic virus (OV). It is actually an OV-gene therapy, which has much better antitumor effect than either gene therapy alone or virotherapy alone in our previously published papers. This study is a modification of CTGVT by inserting a colorectal cancer (CRC) specific suppressor gene, ST13, into a CRC specific oncolytic virus, the Ad·CEA·E1A(Δ24), to construct the Ad·(ST13)·CEA·E1A(Δ24) for increasing the targeting tropism to colorectal cancer and it was briefly named as CTGVT-CRC. Although many studies on CEA promoter and ST13 gene were reported but no construct has been performed to combine both of them as a new strategy for colorectal cancer (CRC) specific therapy. In addition to the CRC specificity, the antitumor effect of Ad·(ST13)·CEA·E1A(Δ24) was also excellent and got nearly complete inhibition (not eradication) of CRC xenograft since ST13 was an effective antitumor gene with less toxicity, and a Chinese patent (No. 201110319434.4) was available for this study. Ad·(ST13)·CEA·E1A(Δ24) caused cell apoptosis through P38 MAPK (i.e. P38) which upregulated CHOP and ATF2 expression. The mitochondrial medicated apoptosis pathway was activated by the increase of caspase 9 and caspase 3 expression.

Complete eradication of hepatomas using an oncolytic adenovirus containing AFP promoter controlling E1A and an E1B deletion to drive IL-24 expression

Interleukin (IL)-24, a promising therapeutic gene, has been widely used for Cancer Targeting Gene-Viro-Therapy (CTGVT). In this study, IL-24 was inserted into an oncolytic adenovirus in which the E1A gene is driven by an enhanced, short α-fetoprotein (AFP) promoter and the E1B gene is completely deleted to form Ad.enAFP-E1A-ΔE1B-IL-24. This construct has a potent antitumor effect on liver cancer cell lines in vitro, but little or no effect on normal cell lines, such as L-02 and QSG-7701. In vivo, the complete elimination of Huh-7 liver cancer in nude mice with Ad.enAFP-E1A-ΔE1B-IL-24 intratumor injection was observed. The design of Ad.enAFP-E1A-ΔE1B-IL-24 and its potent antitumor effect on liver cancer have not been published previously. The mechanism of the potent antitumor effect of Ad.enAFP-E1A-ΔE1B-IL-24 is due to the upregulation of GADD34 and intrinsic and extrinsic apoptotic signaling.

Strategy of Cancer Targeting Gene-Viro-Therapy (CTGVT) a Trend in Both Cancer Gene Therapy and Cancer Virotherapy

Cancer Targeting Gene-Viro-Therapy (CTGVT) and Gene Armed Oncolytic Virus Therapy (GAOVT) both are identical by inserting an antitumor gene into an oncolytic virus. This approach has gradually become a hot topic in cancer therapy, because that CTGVT (GAOVT) has much higher antitumor than that of either gene therapy alone or oncolytic virotherapy alone. We proposed the CTGVT strategy in 1999-2001, insisted it as a long term systematic approach to be examined over 10 years and have published 68 SCI papers some in good Journals. The CD gene armed oncolytic adenovirus therapy (GAOVT) for cancer treatment with potent antitumor effect was also named in our laboratory in 2003. Several modifications to CTGVT will be carried out by our group and will be introduced briefly in this paper. Most importantly, the modifications of CTGVT usually resulted in complete eradication of xenograft tumors in nude mice. In future best antitumor drugs may emerge from the modified CTGVT strategy and not from either gene therapy or virotherapy alone.

A new oncolytic adenoviral vector carrying dual tumour suppressor genes shows potent anti‐tumour effect

Cancer Targeting Gene-Viro-Therapy (CTGVT) is a promising cancer therapeutical strategy that strengthens the anti-tumour effect of oncolytic virus by expressing inserted foreign anti-tumour genes. In this work, we constructed a novel adenoviral vector controlled by the tumour-specific survivin promoter on the basis of the ZD55 vector, which is an E1B55KD gene deleted vector we previously constructed. Compared with the original ZD55 vector, this new adenoviral vector (ZD55SP/E1A) showed much better ability of replication and reporter gene expression. We then combined anti-tumour gene interleukine-24 (IL-24) with an RNA polymerase III-dependent U6 promoter driving short hairpin RNA (shRNA) that targets M-phase phosphoprotein 1 (MPHOSPH1, a newly identified oncogene) by inserting the IL-24 and the shRNA of MPHOSPH1 (shMPP1) expression cassettes into the new ZD55SP/E1A vector. Our results demonstrated excellent anti-tumour effect of ZD55SP/E1A-IL-24-shMPP1 in vitro on multiple cancer cell lines such as lung cancer, liver cancer and ovarian caner. At high multiplicity-of-infection (MOI), ZD55SP/E1A-IL-24-shMPP1 triggered post-mitotic apoptosis in cancer cells by inducing prolonged mitotic arrest; while at low MOI, senescence was induced. More importantly, ZD55SP/E1A-IL-24-shMPP1 also showed excellent anti-tumour effects in vivo on SW620 xenograft nude mice. In conclusion, our strategy of constructing an IL-24 and shMPP1 dual gene expressing oncolytic adenoviral vector, which is regulated by the survivin promoter and E1B55KD deletion, could be a promising method of cancer gene therapy.

Treatment of pancreatic cancer using an oncolytic virus harboring the lipocalin‐2 gene

The 5-year survival rate for patients with pancreatic cancer is <5%, and it is always resistant to the current chemoradiotherapy. Therefore, new, effective agents for the treatment of pancreatic cancer are urgently needed. The promising strategy of cancer-targeting gene virotherapy (CTGVT) has demonstrated great anticancer potential. The objective of the current study was to determine whether 1 CTGVT approach, oncolytic virus (OV)-harboring lipocalin-2, is capable of treating pancreatic cancer. Tissue microarrays were constructed to detect the expression of lipocalin-2 in 60 specimens of pancreatic adenocarcinoma. The clinical significance of lipocalin-2 was investigated in an analysis of correlations between lipocalin-2 expression and matched clinical characteristics. A lipocalin-2-expressing OV, ZD55-lipocalin-2, was constructed by deleting the adenoviral protein E1B55kD. The antitumor efficacy and mechanisms of the OV were investigated in pancreatic cancer cells with v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations in vitro and in vivo. Lipocalin-2 expression was correlated with a good prognosis in patients with pancreatic adenocarcinoma. ZD55-lipocalin-2 dramatically inhibited the growth of pancreatic cancer in vitro and in vivo by inducing cytolysis and caspase-dependent apoptosis. Higher lipocalin-2 expression predicted a better prognosis in patients with pancreatic cancer. The results indicated that ZD55-lipocalin-2, which specifically expressed higher levels of lipocalin-2 in tumor cells, may serve as a potent anticancer drug for pancreatic cancer therapy, especially for patients who have pancreatic adenocarcinoma with KRAS mutations.

Augmenting the Antitumor Effect of TRAIL by SOCS3 with Double-Regulated Replicating Oncolytic Adenovirus in Hepatocellular Carcinoma

Aberrant JAK/STAT3 pathway has been reported to be related to hepatocellular carcinoma (HCC) in many cell lines. In this study, a double-regulated oncolytic adenovirus vector that can replicate and induce a cytopathic effect in alpha-fetoprotein (AFP)-positive HCC cell lines with p53 dysfunction was successfully constructed. Two therapeutic genes, suppressor of cytokine signaling 3 (SOCS3) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), were chosen and incorporated into this vector system, respectively. The combined treatment of AFP-D55-SOCS3 and AFP-D55-TRAIL (2:3 ratio) exhibited potent antitumor activity in AFP-positive HCC cell lines compared with any other treatment both in vitro and in vivo. Specific replication and low progeny yield in AFP-positive HCC cell lines rendered these double-regulated oncolytic adenoviruses remarkably safe. Our data demonstrated that restoration of SOCS3, which inhibits the JAK/STAT3 pathway, by AFP-D55-SOCS3 not only could antagonize HCC therapeutic resistance to TRAIL and adenoviruses, but could also induce cell cycle arrest in HCC cell lines. SOCS3 could down-regulate Cyclin D1 and anti-apoptotic proteins such as XIAP, Survivin, Bcl-xL, and Mcl-1, which are responsible for the synergistic inhibitory effects of AFP-D55-SOCS3 and AFP-D55-TRAIL. Dual gene and double-regulated oncolytic adenoviruses may provide safety and excellent antitumor effects for liver cancer, which is the advantage of a cancer-targeting gene virotherapy strategy.

Cancer targeting Gene-Viro-Therapy of liver carcinoma by dual-regulated oncolytic adenovirus armed with TRAIL gene

Liver cancer is a common and aggressive malignancy, but available treatment approaches remain suboptimal. Cancer targeting Gene-Viro-Therapy (CTGVT) has shown excellent anti-tumor effects in a preclinical study. CTGVT takes advantage of both gene therapy and virotherapy by incorporating an anti-tumor gene into an oncolytic virus vector. Potent anti-tumor activity is achieved by virus replication and exogenous expression of the anti-tumor gene. A dual-regulated oncolytic adenoviral vector designated Ad·AFP·E1A·E1B (Δ55) (Ad·AFP·D55 for short thereafter) was constructed by replacing the native viral E1A promoter with the simian virus 40 enhancer/α-fetoprotein (AFP) composite promoter (AFPep) based on an E1B-55K-deleted construct, ZD55. Ad·AFP·D55 showed specific replication and cytotoxicity in AFP-positive hepatoma cells. It also showed enhanced safety in normal cells when compared with the mono-regulated vector ZD55. To improve the anti-hepatoma activities of the virus, the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) gene was introduced into Ad·AFP·D55. Ad·AFP·D55-TRAIL exhibited remarkable anti-tumor activities in vitro and in vivo. Treatment with Ad·AFP·D55-TRAIL can induce both autophagy owing to the Ad·AFP·D55 vector and caspase-dependent apoptosis owing to the TRAIL protein. Therefore, Ad·AFP·D55-TRAIL could be a potential anti-hepatoma agent with anti-tumor activities due to AFP-specific replication and TRAIL-induced apoptosis.