For a long time past viruses have been recognized as being tumoricidal. At present, researchers are still pursuing studies and constructing more suitable oncolytic viruses for treating different malignant tumors. Herpes simplex virus type 1 (HSV-1) has been known as the most potential oncolytic virus among all the viruses. In this overview, we summarize the current situation of oncolytic viruses, the biology of HSV-1, its construction and application of its recombinant, and we debate on the feasibility and prospect of HSV-1 mutants labeled with radionuclides for cancer therapy.
Herpesvirus 1, Human ; genetics ; physiology ; Humans ; Mutation ; Neoplasms ; radiotherapy ; Oncolytic Virotherapy ; methods ; trends ; Oncolytic Viruses ; genetics

Naturally existing Newcastle disease virus (NDV) can specifically execute oncolytic ability in clinical studies. Reports from clinical trials using NDV as oncolytic agents showed promise and warrant results in cancer therapy. In recent years, reverse genetics technology has been used widely in the studies of NDV virology. More recently, the technology was applied to optimize the oncolytic efficacy of NDV, for instance, modification of the F gene, and expression of GM-CSF, IFN-gamma, IL-2 or TNF-alpha. NDV is widely investigated in cancer therapy and will definitely offer a prosperous future for clinical cancer therapeutics. We reviewed the developments of cancer therapy by recombinant NDV using reverse genetics technology, as well as our own experience in this domain.
Animals ; Humans ; Neoplasms ; pathology ; therapy ; Newcastle disease virus ; genetics ; physiology ; Oncolytic Virotherapy ; methods ; Oncolytic Viruses ; genetics ; physiology ; Recombination, Genetic

Human adenoviruses are widespread causative agent that induces respiratory diseases, epidemic keratoconjunctivitis and other related diseases. Adenoviruses are commonly used in experimental and clinical areas. It is one of the most commonly used virus vectors in gene therapy, and it has attracted a lot of attention and has a high research potential in tumor gene therapy and virus oncolytic. Here, we summarize the biological characteristics, epidemiology and current application of adenovirus, in order to provide reference for engineering application of adenovirus.
Adenovirus Infections, Human ; epidemiology ; virology ; Adenoviruses, Human ; genetics ; Genetic Engineering ; methods ; trends ; Genetic Vectors ; Humans ; Oncolytic Virotherapy ; trends ; Oncolytic Viruses ; genetics ; Virus Replication

OBJECTIVETo construct an oncolytic adenovirus with the DD3 promoter regulation, expressing small hairpin RNA and targeting the SATB1 gene (SATBI-shRNA), and to evaluate its potential for inhibiting the growth of human prostatic carcinoma cells (LNCaP) in vitro.

METHODSSATB1-shRNA expression cassettes containing the H1 promoter were produced by PCR from pSilencer3. 1-SATB1 and inserted into the pZD55 vector, and the recombinant plasmid pZD55-SATB1-shRNA was constructed, pZD55SATB1-shRNA and pZXC2-DD3-E1A were digested with EcoRV and Xba I , and the obtained expression cassettes linked each other to construct the recombinant plasmid pDD3-ZD55-SATB1, which was cotransfected with the pBHGE3 packaging plasmids mixture into 293 cells by Effectence. The recombined adenoviruses DD3-ZD55-SATB1 were identified by PCR. Viruses were propagated on HEK293 cells and purified by standard techniques, and the functional PFU titers determined by plaque assay on 293 cells. The antitumor potential of DD3-ZD55-SATB1 to LNCaP was evaluated by the crystal violet dye method. The expression level of the E1A gene was detected by Western blot, and that of the SATB1 gene in the adenovirus-infected LNCaP cells by both Western blot and RT-PCR.

RESULTSAn oncolytic adenovirus expressing SATB1-shRNA with the DD3 promoter regulation, DD3-ZD55-SATB1, was constructed successfully, whose functional PFU titer was 1.2 x 10(10) PFU/ml. DD3-ZD55-SATB1 showed an obvious cytopathic effect and a selective expression of E1A in the adenovirus-infected LNCaP cells; it exhibited a high LNCaP-targetability and specific SATB1-silencing effect.

CONCLUSIONThe successful construction of the oncolytic adenovirus DD3-ZD55-SATB1 offers a new tool for researches on the gene therapy for human prostate cancer.

Adenoviridae ; genetics ; Carcinoma ; therapy ; Cell Line, Tumor ; Genetic Vectors ; Humans ; Male ; Matrix Attachment Region Binding Proteins ; genetics ; Oncolytic Virotherapy ; methods ; Oncolytic Viruses ; genetics ; Promoter Regions, Genetic ; Prostatic Neoplasms ; therapy ; RNA Interference ; RNA, Small Interfering ; genetics

Oncolytic herpes simplex virus (HSV) can replicate in and kill cancer cells without harming normal tissue. G47delta is a third-generation HSV vector. In this study, the therapeutic effects of G47delta on human nasopharyngeal carcinoma (NPC) were determined in vitro and in vivo. The human NPC cell lines CNE-2 and SUNE-1, primary normal nasopharyngeal epithelial cells (NPECs), and immortalized nasopharyngeal cells NP-69 and NPEC2/Bmi1 were infected with G47delta at different multiplicities of infection (MOIs). The survival of infected cells was observed daily. Two subcutaneous models of NPC were established with CNE-2 and SUNE-1 in Balb/c nude mice. G47delta or virus buffer as control was injected into the subcutaneous tumors. Tumor size was measured twice a week, and animals were euthanized when the diameter of their tumors exceeded 18 mm or when the animals appeared moribund. For the NPC cell lines CNE-2 and SUNE-1, more than 85% and 95% of cells were killed on day 5 after G47delta infection at MOI = 0.01 and MOI = 0.1, respectively. Similar results were observed for an immortalized cell line NPEC2/Bmi-1. A moderate effect of G47delta was also found on another immortalized cell line NP-69, of which only 27.7% and 75.9% of cells were killed at MOI = 0.01 and MOI = 0.1, respectively. On the contrary, there was almost no effect observed on NPECs. The in vivo experiments showed that tumors in mice in the G47delta-treated group regressed completely, and the mice exhibited much longer survival time than those in the control groups. Our results suggest that the potential therapeutic effects of G47delta would be applicable for treatment of NPC patients in the future.
Animals ; Apoptosis ; Carcinoma ; Cell Line, Tumor ; Female ; Humans ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Nasopharyngeal Neoplasms ; pathology ; therapy ; virology ; Oncolytic Virotherapy ; methods ; Oncolytic Viruses ; physiology ; Simplexvirus ; physiology ; Xenograft Model Antitumor Assays

In the last decade, we have gained significant understanding of the mechanism by which vesicular stomatitis virus (VSV) specifically kills cancer cells. Dysregulation of translation and defective innate immunity are both thought to contribute to VSV oncolysis. Safety and efficacy are important objectives to consider in evaluating VSV as a therapy for malignant disease. Ongoing efforts may enable VSV virotherapy to be considered in the near future to treat drug-resistant ovarian cancer when other options have been exhausted. In this article, we review the development of VSV as a potential therapeutic approach for recurrent or drug-resistant ovarian cancer.
Animals ; Antineoplastic Agents ; pharmacology ; Apoptosis ; Cell Proliferation ; Drug Resistance, Neoplasm ; Female ; Humans ; Neoplasm Recurrence, Local ; Oncolytic Virotherapy ; methods ; Ovarian Neoplasms ; pathology ; therapy ; virology ; Vesicular stomatitis Indiana virus ; physiology ; Virus Replication

OBJECTIVE: To evaluate the inhibitory role of a novel oncolytic adenovirus (OA), GP73-SphK1sR-Ad5, on the growth of hepatocellular carcinoma (HCC). METHODS: GP73-SphK1sR-Ad5 was constructed by integrating Golgi protein 73 (GP73) promoter and sphingosine kinase 1 (SphK1)-short hairpin RNA (shRNA) into adenovirus serotype 5 (Ad5), and transfecting into HCC Huh7 cells and normal human liver HL-7702 cells. The expression of SphK1 and adenovirus early region 1 (E1A) was detected by quantitative real-time PCR (qRT-PCR) and western blot, respectively. Cell viability was detected by methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay, and apoptotic rate was determined by flow cytometry. An Huh7 xenograft model was established in mice injected intratumorally with GP73-SphK1sR-Ad5. Twenty days after injection, the tumor volume and weight, and the survival time of the mice were recorded. The histopathological changes in tumor tissues were observed by hematoxylin-eosin (HE) staining and transmission electron microscopy (TEM). RESULTS: Transfection of GP73-SphK1sR-Ad5 significantly upregulated E1A and downregulated SphK1 in Huh7 cells, but not in HL7702 cells. GP73-SphK1sR-Ad5 transfection significantly decreased the viability and increased the apoptotic rate of Huh7 cells, but had no effect on HL7702 cells. Intratumoral injection of GP73-SphK1sR-Ad5 into the Huh7 xenograft mouse model significantly decreased tumor volume and weight, and prolonged survival time. It also significantly decreased the tumor infiltration area and blood vessel density, and increased the percentages of cells with nucleus deformation and cells with condensed chromatin in tumor tissues. CONCLUSIONS GP73-SphK1sR-Ad5 serves as a novel OA and can inhibit HCC progression with high specificity and efficacy.
Adenoviridae ; Animals ; Apoptosis ; Carcinoma, Hepatocellular/therapy* ; Cell Line, Tumor ; Female ; Liver Neoplasms/therapy* ; Membrane Proteins/genetics* ; Mice ; Mice, Inbred BALB C ; Oncolytic Virotherapy/methods* ; Phosphotransferases (Alcohol Group Acceptor)/genetics* ; Promoter Regions, Genetic

OBJECTIVETo evaluate the effect of combined use of oncolytic virus and the chemotherapeutic agents mitomycin (MMC) in growth inhibition of human bladder cancer cell line T-24 in vitro.

METHODSHuman bladder cancer cell line T-24 was infected with oncolytic virus (ONYX-015) of different multiplicity of infection, or treated with MMC in addition to ONYX-015. The changes in the cell growth, morphology, and apoptosis of cultured T-24 cells were observed by means of cell counting and fluorescence microscopy after the treatments. The effects of the treatment protocols were also tested in nude mouse model of implanted subcutaneous tumor.

RESULTSCombined use of ONYX-015 and MMC produced substantially stronger cytotoxic effect against T-24 cells than exclusive use of ONYX-015. In in vivo experiments, combination of oncolytic virus and MMC resulted in much more significant tumor growth inhibition than either of the agents used alone. Obvious T-24 cell apoptosis could be observed in response to combined ONYX-105 and MMC treatment and exclusive ONYX-105 treatment.

CONCLUSIONSONYX-015 combined with MMC can produce significant cytotoxicity against T-24 cells and enhance therapeutic efficacy against bladder carcinoma.

Animals ; Antibiotics, Antineoplastic ; pharmacology ; therapeutic use ; Apoptosis ; drug effects ; physiology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cell Survival ; drug effects ; Combined Modality Therapy ; Female ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Mitomycin ; pharmacology ; therapeutic use ; Oncolytic Virotherapy ; methods ; Oncolytic Viruses ; physiology ; Urinary Bladder Neoplasms ; pathology ; therapy ; virology ; Xenograft Model Antitumor Assays

PURPOSE: We have used a genetically attenuated adenoviral vector which expresses HSVtk to assess the possible additive role of suicidal gene therapy for enhanced oncolytic effect of the virus. Expression of TK was measured using a radiotracer-based molecular counting and imaging system. MATERIALS AND METHODS: Replication-competent recombinant adenoviral vector (Ad-deltaE1B19/55) was used in this study, whereas replication-incompetent adenovirus (Ad-deltaE1A) was generated as a control. Both Ad-deltaE1B19/55-TK and Ad-deltaE1A-TK comprise the HSVtk gene inserted into the E3 region of the viruses. YCC-2 cells were infected with the viruses and incubated with 2'-deoxy-2'-fluoro-beta-D-arabinofuranosyl-5-iodouracil (I-131 FIAU) to measure amount of radioactivity. The cytotoxicity of the viruses was determined, and gamma ray imaging of HSVtk gene was performed. MTT assay was also performed after GCV treatment. RESULTS: On gamma counter-analyses, counts/minute (cpm)/microgram of protein showed MOIs dependency with deltaE1B19/55-TK infection. On MTT assay, Ad-deltaE1B19/55-TK led to more efficient cell killing than Ad-deltaE1A-TK. On plate imaging by gamma camera, both Ad-deltaE1B19/55-TK and Ad-deltaE1A-TK infected cells showed increased I-131 FIAU uptake in a MOI dependent pattern, and with GCV treatment, cell viability of deltaE1B19/55-TK infection was remarkably reduced compared to that of Ad-deltaE1A-TK infection. CONCLUSION: Replicating Ad-deltaE1B19/55-TK showed more efficient TK expression even in the presence of higher-cancer cell killing effects compared to non-replicating Ad-deltaE1A-TK. Therefore, GCV treatment still possessed an additive role to oncolytic effect of Ad-deltaE1B19/55-TK. The expression of TK by oncolytic viruses could rapidly be screened using a radiotracer-based counting and imaging technique.
Adenoviridae/*genetics/physiology ; Cell Line, Transformed ; Cell Line, Tumor ; Ganciclovir/pharmacology ; Gene Expression ; Gene Therapy/methods ; Genetic Vectors ; Humans ; *Oncolytic Virotherapy ; Oncolytic Viruses/*genetics/physiology ; Simplexvirus/genetics ; Tetrazolium Salts/analysis ; Thiazoles/analysis ; Thymidine Kinase/*genetics/metabolism ; Transgenes ; Viral Proteins/*genetics/metabolism ; Virus Replication

OBJECTIVEThe aim of this study was to construct a new oncolytic virus oHSV2hGM-CSF and evaluate its oncolytic activity in vitro and in vivo in parallel with oHSV1hGM-CSF.

METHODSoHSV2hGM-CSF was a replication-competent, attenuated HSV2 based on the HG52 virus (an HSV2 strain). It was engineered to be specific for cancer by deletion of the viral genes ICP34.5 and ICP47 and insertion of the gene encoding hGM-CSF. To measure the in vitro killing effect of the virus, 15 human tumor cell lines (HeLa, Eca-109, PG, HepG2, SK/FU, CNE-2Z, PC-3, SK-OV3, A-549, 786-0, MCF-7, Hep-2, HT-29, SK-Mel-28, U87-MG) and mouse melanoma (B16R) cell line were seeded into 24-well plates and infected with viruses at MOI = 1 (multiplicity of infection, MOI), or left uninfected. The cells were harvested 24 and 48 hours post infection, and observed under the microscope. For animal studies, the oncolytic viruses were administered intratumorally (at 3-day interval) at a dose of 2.3 x 10(6) PFU (plaque forming unit, PFU) for three times when the tumor volume reached 7-8 mm3. The tumor volume was measured at 3-day intervals and animal survival was recorded.

RESULTSBoth oHSV2hCM-CSFand oHSV1hGM-CSF induced widespread cytopathic effects at 24 h after infection. OHSV2hGM-CSF, by contrast, produced more plaques with a syncytial phenotype than oHSV1hGM-CSF. In the in vitro killing experiments for the cell lines HeLa, HepG2, SK-Mel-28, B16R and U87-MG, oHSV2hGM-CSF eradicated significantly more cells than oHSV1hGM-CSF under the same conditions. For the mouse experiments, it was observed that oHSV2hGM-CSF significantly inhibited the tumor growth. At 15 days after B16R tumor cells inoculation, the tumor volumes of the PBS, oHSV1hGCM-CSF and oHSV2hGM-CSF groups were (374.7 +/- 128.24) mm3, (128.23 +/- 45.32) mm3 (P < 0.05, vs. PBS group) or (10.06 +/- 5.1) mm3 (P < 0.01, vs. PBS group), respectively (mean +/- error). The long term therapeutic effect of oHSV2hGM-CSF on the B16R animal model was evaluated by recording animal survival over 110 days after tumor cells inoculation whereas all the mice in the PBS group died by day 22 (P < 0.01). The anti-tumor mechanism of the newly constructed oHSV2hGM-CSF against B16R cell tumor appeared to include the directly oncolytic activity and the induction of anti-tumor immunity to some degree.

CONCLUSIONThe findings of our study demonstrate that the newly constructed oHSV2hGM-CSF has potent anti-tumor activity in vitro to many tumor cell lines and in vive to the transplanted B16R tumor models.

Animals ; Cell Line, Tumor ; Female ; Gene Deletion ; Genetic Engineering ; Granulocyte-Macrophage Colony-Stimulating Factor ; genetics ; Herpesvirus 2, Human ; genetics ; immunology ; Humans ; Immediate-Early Proteins ; genetics ; metabolism ; Melanoma, Experimental ; pathology ; therapy ; virology ; Mice ; Mice, Inbred C57BL ; Oncolytic Virotherapy ; methods ; Oncolytic Viruses ; genetics ; physiology ; Random Allocation ; Tumor Burden ; Viral Proteins ; genetics ; metabolism ; Xenograft Model Antitumor Assays