Progress in engineering application of human adenovirus / 生物工程学报

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.

Inactivated Sendai Virus Induces ROS-dependent Apoptosis and Autophagy in Human Prostate Cancer Cells / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>The current study aims to investigate the effect of Hemagglutinating virus of Japan envelope (HVJ-E) on induction of apoptosis and autophagy in human prostate cancer PC3 cells, and the underlying mechanisms.</p><p><b>METHODS</b>PC3 cells were treated with HVJ-E at various multiplicity of infection (MOI), and the generated reactive oxygen species (ROS), cell viability, apoptosis, and autophagy were detected, respectively. Next, the role of ROS played in the regulation of HVJ-E-induced apoptosis and autuphagy in PC3 cells were analysed. In the end, the relationship between HVJ-E-induced apoptosis and autuophagy was investigated by using rapamycin and chloroquine.</p><p><b>RESULTS</b>Flow cytometry assay revealed that HVJ-E treatment induced dose-dependent apoptosis and that the JNK and p38 MAPK signaling pathways were involved in HVJ-E-induced apoptosis in PC3 cells. In addition, HVJ-E was able to induce autophagy in PC3 cells via the class III PI3K/beclin-1 pathway. The data also implyed that HVJ-E-triggered autophagy and apoptosis were ROS dependent. When ROS was blocked with N-acetylcysteine (NAC), HVJ-E-induced LC3-II conversion and apoptosis were reversed. Interestingly, HVJ-E-induced apoptosis was significantly increased by an inducer of autophagy, rapamycin pretreatment, both in vitro and in vivo.</p><p><b>CONCLUSION</b>HVJ-E exerts anticancer effects via autophagic cell death in prostate cancer cells.</p>

Is oncolytic virotherapy a viable platform for glioma treatment?

Gliomas are devastating cancers of the nervous system with poor prognosis. Their aggressiveness produces a mortality rate rarely seen with other malignant tumours and the lack of effective treatment has left very few options. On-colytic viruses, with their long history of experimentation, have been deemed to be a key player in the future treatment of gliomas. This review will focus on the two main contenders, adenovirus and herpes simplex virus, for glioma treatment and discuss how far the field has come since its conception. The concept of each vector and the rationales behind their use will be contrasted before discussing the future of the field. Data was located by accessing the MEDLINE database using the PubMed search system. Data was selected on the basis of the insight its information provided as well as on the dependability of the experimental method used

Advances in measles virus for cancer therapy / 浙江大学学报·医学版

Oncolytic virotherapy is a novel cancer therapy. Vaccine-attenuated strains of measles virus(MV)is an ideal candidate for oncolytic virotherapy which has an excellent safety record. Vaccine-attenuated MV uses CD46 and Nectin-4 molecule as major entry receptors into cells. Vaccine-attenuated MV can selectively infect and kill a wide variety of cancer cells in vitro and in vivo. With the development of molecular cloning, scientists have successfully rescued cDNA of vaccine-attenuated MV and increased its oncolytic efficiency with molecular engineering techniques. Phase I clinical trials of virotherapy for ovarian cancer and multiple myeloma with vaccine-attenuated MV are underway. The preliminary results indicate the promising antitumor potential of vaccine-attenuated MV.

Terapia génica para el tratamiento del cáncer / Gene therapy for cancer treatment

El cáncer es una enfermedad compleja de etiología desconocida. Factores genéticos y epigenéticos se asocian al incremento en el riesgo de desarrollar esta enfermedad. A pesar del avance en los tratamientos tradicionales contra el cáncer, el pronóstico de los pacientes no ha mejorado significativamente. Estudios en la patogénesis molecular del cáncer han evidenciado la existencia de dianas moleculares con potencial terapéutico que permiten trasladar los conocimientos de la investigación básica a la clínica implementando nuevas terapias para el beneficio del paciente. El conocimiento del genoma viral, su función, replicación y los mecanismos de infección a la célula tumoral han permitido el desarrollo de la terapia génica viral que puede ser la herramienta ideal para el tratamiento del cáncer. Este artículo revisa diferentes metodologias desarrolladas para el diseno de una terapia génica contra el cáncer, abordada desde diferentes contextos biológicos, y su aplicación clínica para el tratamiento del cáncer.

Cancer is a complicated disease of unknown etiology. Genetic and epigenetic factors are associated with an increased risk for developing this disease. Despite the progress in the traditional cancer therapies, the prognosis of patients has not improved significantly. Studies on the molecular pathogenesis of cancer have demonstrated the existence of molecular targets with therapeutic potential. Furthermore, knowledge of the viral genome function and replication, as well as of the mechanisms of tumor cell infection, have made it possible to develop an ideal tool for gene therapy against cancer and thus, enable the transfer of knowledge from basic to clinical research for the benefit of patients. This article reviews different methodologies developed to design a cancer gene therapy and its clinical application for treating cancer, addressed from various biological contexts.

Artificial neural network analysis in preclinical breast cancer

In this study, artificial neural network [ANN] analysis of virotherapy in preclinical breast cancer was investigated. In this research article, a multilayer feed-forward neural network trained with an error back-propagation algorithm was incorporated in order to develop a predictive model. The input parameters of the model were virus dose, week and tamoxifen citrate, while tumor weight was included in the output parameter. Two different training algorithms, namely quick propagation [QP] and Levenberg-Marquardt [LM], were used to train ANN. The results showed that the LM algorithm, with 3-9-1 arrangement is more efficient compared to QP. Using LM algorithm, the coefficient of determination [R[2]] between the actual and predicted values was determined as 0.897118 for all data. It can be concluded that this ANN model may provide good ability to predict the biometry information of tumor in preclinical breast cancer virotherapy. The results showed that the LM algorithm employed by Neural Power software gave the better performance compared with the QP and virus dose, and it is more important factor compared to tamoxifen and time [week]

Advances in research on oncolytic adenoviruses in tumor therapy / 病毒学报

Oncolytic adenoviruses (Ads), which are live, replication-competent viruses that can selectively replicate in tumor cells and lead to cell lysis, have been used in tumor therapy. But due to the complexity and high mutability of human tumors, it becomes a major strategy to improve the selectivity, efficacy, and safety of oncolytic Ads. The oncolytic Ads that can express short hairpin RNA, cytokines, suicide gene, and matrix-modulating proteins have higher antitumor activity than the wild type. Tumor-specific promoters, especially hTERT and HRE promoters, increase the selectivity of oncolytic Ads for tumor cells. Moreover, oncolytic Ads surface-modified by polyethylene glycol (PEG), liposomes, biodegradable nanoparticles, and polypeptides have reduced immunogenicity and hepatotoxicity and improved antitumor activity when systemically administered, and the selectivity of oncolytic Ads can be significantly increased when linking PEG to antibodies, small peptides, cytokines, and ligands. Therefore, engineered oncolytic Ads combining the advantages of viral and non-viral vectors, as well as immunotherapy, are a promising strategy for improving the efficacy of targeted virotherapy.

Induction of apoptosis in hormone-resistant human prostate cancer PC3 cells by inactivated Sendai virus / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>Inactivated Sendai virus particle [hemagglutinating virus of Japan envelope (HVJ-E)] has a potential oncolytic effect due to its ability to induce apoptosis in tumor cells. However, the molecular mechanism of apoptosis induction in cancer cells mediated by HVJ-E has not been fully elucidated. This paper aims to investigate the underlying mechanism of apoptosis induction by HVJ-E in prostate cancer cells (PC3).</p><p><b>METHODS</b>PC3 cells were treated with HVJ-E at various MOI, and then interferon-β (IFN-β) production, and the cell viability and apoptosis were detected by ELISA, MTT-based assay and flow cytometry, respectively. Next, the roles of Jak-Stat, MAPK and Akt pathways played in HVJ-E-induced apoptosis in PC3 cells were analyzed by immunoblot assay. To further evaluate the cytotoxic effect of HVJ-E on PC3 cells, HVJ-E was intratumorally injected into prostate cancers on BALB/c-nude mice, and the tumor volume was monitored for 36 days.</p><p><b>RESULTS</b>HVJ-E induced IFN-β production and activated Jak-Stat signaling pathway, which resulted in the activation of caspase-8, caspase-3, and PARP in PC3 prostate cancer cells post HVJ-E treatment. Furthermore, we observed for the first time that p38 and Jnk MAPKs in PC3 cells contributed to HVJ-E-induced apoptosis. In addition, intratumoral HVJ-E treatment displayed a direct inhibitory effect in an in vivo BALB/c nude mouse prostate cancer model.</p><p><b>CONCLUSION</b>Our findings have provided novel insights into the underlying mechanisms by which HVJ-E induces apoptosis in tumor cells.</p>

Oncolytic viruses & their specific targeting to tumour cells.

Cancer is one of the major causes of death worldwide. In spite of achieving significant successes in medical sciences in the past few decades, the number of deaths due to cancer remains unchecked. The conventional chemotherapy and radiotherapy have limited therapeutic index and a plethora of treatment related side effects. This situation has provided an impetus for search of novel therapeutic strategies that can selectively destroy the tumour cells, leaving the normal cells unharmed. Viral oncotherapy is such a promising treatment modality that offers unique opportunity for tumour targeting. Numerous viruses with inherent anti-cancer activity have been identified and are in different phases of clinical trials. In the era of modern biotechnology and with better understanding of cancer biology and virology, it has become feasible to engineer the oncolytic viruses (OVs) to increase their tumour selectivity and enhance their oncolytic activity. In this review, the mechanisms by which oncolytic viruses kill the tumour cells have been discussed as also the development made in virotherapy for cancer treatment with emphasis on their tumour specific targeting.

Study in the killing effect of Myxoma virus to C6 glioma cell in vitro / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To evaluate the susceptibility of C6 glioma cells to Myxoma virus and the killing effect of Myxoma virus to the C6 glioma cells in vitro.</p><p><b>METHODS</b>C6 glioma cells were infected with myxoma virus, used death virus as the negative control, 5-FU as the positive control, DEMD as blank control. The number of living cells were counted every 24 h, and Western-Blot method, inverted microscope and MTT assay were applicated to observe the cell morphology and survival rate in each group.</p><p><b>RESULTS</b>The cell number were decreased rapidly in virus effected group and 5-FU group, with significant differences to the negative and blank control groups. And cells in virus effected group appeared cytopathic effect.</p><p><b>CONCLUSIONS</b>C6 glioma cells were susceptible to myxoma virus and myxoma virus had killing effect to C6 glioma cells in vitro.</p>

Effects of myxoma virus on gliomas of rats models in vivo / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To explore the in vivo effects of myxoma virus (MV) on gliomas of rat model. Methods C6 glioma cells were implanted into the frontal lobe of SD rats using stereotactic methods to establish animal models of glioma.</p><p><b>METHODS</b>C6 glioma cells were implanted into the frontal lobe of SD rats using stereotactic methods to establish animal models of glioma. Models were divided into 4 groups randomly after tumor growth was affirmed, and MV, 5-FU, MV + 5-FU, and denatured myxoma virus (DV) were implanted into the tumors using stereotactic methods, bodyweight, tumor size, expression of glial fibrillary acidic protein (GFAP), Akt of each model were observed.</p><p><b>RESULTS</b>The gliomas in all SD rats were established successfully. And tumor growth in MV, 5-FU, MV + 5-FU were significantly decreased as compared with DV group after injection, sizes of some tumors were lessened, and GFAP expression decreased in MV, 5-FU and MV +5-FU groups. The expression of PI3k, Akt and mTOR were decreased in MV and MV +5-FU groups.</p><p><b>CONCLUSION</b>C6 glioma SD rat models could be established successfully using stereotactic methods. MV may enhance biological activity of chemotherapeutic drugs on tumor cells of animal models in vivo by regulating some genes of PI3K-Akt-mTOR signal pathway.</p>

Application of mesenchymal stem cells as a vehicle to deliver replication-competent adenovirus for treating malignant glioma / 癌症

Although gene therapy was regarded as a promising approach for glioma treatment, its therapeutic efficacy was often disappointing because of the lack of efficient drug delivery systems. Mesenchymal stem cells(MSCs) have been reported to have a tropism for brain tumors and thus could be used as delivery vehicles for glioma therapy. Therefore, in this study, we attempted to treat glioma by using MSCs as a vehicle for delivering replication-competent adenovirus. We firstly compared the infectivity of type 3, type 5, and type 35 fiber-modified adenoviruses in MSCs. We also determined suitable adenovirus titer in vitro and then used this titer to analyze the ability of MSCs to deliver replication-competent adenovirus into glioma in vivo. Our results indicated that type 35 fiber-modified adenovirus showed higher infectivity than did naked type 3 or type 5 fiber-modified adenovirus. MSCs carrying replication-competent adenovirus significantly inhibited tumor growth in vivo compared with other control groups. In conclusion, MSCs are an effective vehicle that can successfully transport replication-competent adenovirus into glioma, making it a potential therapeutic strategy for treating malignant glioma.

Construction of a new oncolytic virus oHSV2hGM-CSF and its anti-tumor effects / 中华肿瘤杂志

<p><b>OBJECTIVE</b>The 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.</p><p><b>METHODS</b>oHSV2hGM-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.</p><p><b>RESULTS</b>Both 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.</p><p><b>CONCLUSION</b>The 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.</p>

Antitumour efficacy of a novel oncolytic adenovirus Ad-TD-RFP for human nasopharyngeal carcinoma / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To evaluate the antitumor efficacy of Ad-TD-RFP for human nasopharyngeal carcinoma cells (C666-1) in vitro and in vivo.</p><p><b>METHODS</b>The oncolytic effects of Ad-TD-RFP and control virus dl11520 on C666-1 cells were determined by cytotoxicity assay (MTS assay). Viral replication of Ad-TD-RFP and dl11520 was detected at different time points (24 h, 48 h, 72 h and 96 h) by tissue culture infective dose (TCID(50)) in C666-1 cells implanted subcutaneously into the flank in each of BALB/c nude mice. The xenografts were injected intratumorally with Ad-TD-RFP or dl1520 to investigate their effects on tumor growth.</p><p><b>RESULTS</b>The concentration for 50% of maximal effect (EC(50)) values of Ad-TD-RFP and dl1520 were (107.6 ± 3.2) pt/cell and (174.1 ± 4.0) pt/cell, respectively (t = 22.6, P < 0.001). The Ad-TD-RFP replication was 3-14 folds more than dl1520 replication at four time points (24 h, 48 h, 72 h and 96 h) in C666-1 cells (t values were 33.6, 23.4, 20.8 and 17.3, respectively, P < 0.001). The average tumor volumes of PBS group, dl1520 group and Ad-TD-RFP group were (1765.5 ± 713.9) mm(3), (1036.9 ± 623.8) mm(3), and (420.8 ± 238.7) mm(3), respectively (F = 12.0, P < 0.05) on day 67 after treatment.</p><p><b>CONCLUSIONS</b>The antitumour efficacy of the novel oncolytic adenovirus Ad-TD-RFP for human nasopharyngeal carcinoma C666-1 cells is superior to that of dl1520 in vitro and in vivo. The outcome of this study provides an experimental basis for the treatment of human nasopharyngeal carcinoma by viral gene therapy.</p>

E1A, E1B double-restricted adenovirus enhances the cytotoxicity and antitumor activity of gemcitabine to renal cell carcinoma / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Our previous studies have demonstrated potent oncolysis efficacy of the E1A, E1B double-restricted replication-competent oncolytic adenovirus AxdAdB-3 for treatment of bladder cancer. Here, we reported the feasibility and efficacy of AxdAdB-3 alone, or in combination with gemcitabine for treating renal cell carcinoma.</p><p><b>METHODS</b>Cytopathic effects of AxdAdB-3 were evaluated in human renal cell carcinoma cell lines TOS-1, TOS-2, TOS-3, TOS-3LN, SMKT-R3, SMKT-R4 and ACHN, and in normal human renal proximal tubule epithelial cells (RPTEC). AxdAdB-3 induced down-regulation of the cell cycle was determined by flow cytometry. Combination therapies of AxdAdB-3 with gemcitabine were evaluated in vitro and in vivo on subcutaneous TOS-3LN tumors in a severe combined immunodeficiency disease (SCID) mouse model.</p><p><b>RESULTS</b>AxdAdB-3 was potently cytopathic against the tested most renal cell carcinoma cell lines including TOS-2, TOS-3, TOS-3LN, SMKT-R3 and SMKT-R4, while normal human RPTEC were not destroyed. AxdAdB-3 effectively induced cell cycle S-phase entry. Combined therapy of AxdAdB-3 with gemcitabine demonstrated stronger antitumor effects in vitro and in vivo compared with either AxdAdB-3 or gemcitabine alone.</p><p><b>CONCLUSION</b>AxdAdB-3 alone, or in combination with gemcitabine may be a promising strategy against renal cell carcinoma.</p>

Potential of vesicular stomatitis virus as an oncolytic therapy for recurrent and drug-resistant ovarian cancer / 癌症

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.

Anti-tumor effect of oncolytic herpes simplex virus G47delta on human nasopharyngeal carcinoma / 癌症

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.

Effect of CEA gene regulation on the anti-tumor activity of oncolytic adenovirus H101 to esophageal carcinoma / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To study the effect of CEA gene regulation on the anti-tumor activity of oncolytic adenovirus H101 to esophageal carcinoma, and to explore the intrinsic factors influencing H101 sensitivity.</p><p><b>METHODS</b>Stable human esophageal cancer cell line EC9706 cells with lower (EC9706-SCEA) and higher CEA expression (EC9706-CEA) were chosen, thawed and cultured, and then to analyse the influence of CEA expressed at different levels on cell growth. The cytotoxic effect of H101 was assayed by in vitro and nude mouse in vivo.</p><p><b>RESULTS</b>The cell growth experiment showed that the population doubling time of EC9706-SCEA, EC9706-CEA and EC9706 cells were (30.9 ± 2.0) h, (31.1 ± 2.5) h and (29.1 ± 2.6) h, respectively, showing no significant difference among them (P > 0.05). The cytotoxic activity of H101 was higher on EC9706-SCEA than on other four groups, when MOI was ≥ 0.01 PFU (P < 0.05). The mouse experiment showed that H101 inhibited the growth of transplanted tumors in all experimental groups. Its effect on CEA-silenced tumors (inhibition rate was 61.5% to 74.5%) was significantly higher than that on CEA-overexpression tumors (32.3% to 38.5%) and control EC9706 transplanted tumors (35.5% to 44.8%). There was a significant difference between them (P < 0.05).</p><p><b>CONCLUSIONS</b>The results in vitro and in vivo experiments show that H101 can enhance the cytotoxic effect on EC9706 cells with lower CEA expression. To silence the expression of CEA may provide a novel strategy for target gene therapy of esophageal carcinoma.</p>

Effect of aldosterone on the amplification of oncolytic vaccinia virus in human cancer lines / 대한간학회지

BACKGROUND/AIMS: JX-594 is an oncolytic virus derived from the Wyeth vaccinia strain that causes replication-dependent cytolysis and antitumor immunity. Starting with a cross-examination of clinical-trial samples from advanced hepatocellular carcinoma patients having high levels of aldosterone and virus amplification in JX-594 treatment, we investigated the association between virus amplification and aldosterone in human cancer cell lines. METHODS: Cell proliferation was determined by a cell-counting-kit-based colorimetric assay, and vaccinia virus quantitation was performed by quantitative polymerase chain reaction (qPCR) and a viral plaque assay. Also, the intracellular pH was measured using a pH-sensitive dye. RESULTS: Simultaneous treatment with JX-594 and aldosterone significantly increased viral replication in A2780, PC-3, and HepG2 cell lines, but not in U2OS cell lines. Furthermore, the aldosterone treatment time altered the JX-594 replication according to the cell line. The JX-594 replication peaked after 48 and 24 hours of treatment in PC-3 and HepG2 cells, respectively. qPCR showed that JX-594 entry across the plasma membrane was increased, however, the changes are not significant by the treatment. This was inhibited by treatment with spironolactone (an aldosterone-receptor inhibitor). JX-594 entry was significantly decreased by treatment with EIPA [5-(N-ethyl-N-isopropyl)amiloride; a Na+/H+-exchange inhibitor], but aldosterone significantly restored JX-594 entry even in the presence of EIPA. Intracellular alkalization was observed after aldosterone treatment but was acidified by EIPA treatment. CONCLUSIONS: Aldosterone stimulates JX-594 amplification via increased virus entry by affecting the H+ gradient.

Mechanisms of enhanced antileukemia activity of conditionally replicating adenovirus (CRAd) ZD55 by interleukin-24 / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the mechanisms of enhanced antileukemia activity of conditionally replicating adenovirus (CRAd) by interleukin-24 (IL-24).</p><p><b>METHODS</b>The ability of CRAd ZD55 to infect leukemia cells was detected by flow cytometry. The expressions of vascular endothelial growth factor (VEGF) in leukemia cells treated with PBS, ZD55, ZD55-IL-24, and an adenovirus carrying IL-24 (Ad-IL-24) were determined by Western blot analysis. Animal xenograft tumor model was established by Mutz-1 cell line.Deparaffinized tumor sections were incubated with anti-CD31, and VEGF antibody, followed by immunohistochemistry analysis.</p><p><b>RESULT</b>The GFP-positive cells were 5.1% and 42.3% in Mutz-1 cells treated with ZD55-EGFP vector at MOI of 10 and 100 for 48h, respectively. ZD55-IL-24 treatment resulted in the marked down-regulation of VEGF protein expression and ZD55 inhibited VEGF slightly; however, there was no change observed in the cells treated with Ad-IL-24. Immunohistochemistry analysis showed that Ad-IL-24 inhibited slightly angiogenesis and ZD55 treatment resulted in significant inhibition of angiogenesis. ZD55-IL-24 treatment almost completely inhibited angiogenesis in tumor tissues.</p><p><b>CONCLUSION</b>IL-24 enhances the antileukemia activity of ZD55 by inhibiting VEGF protein expression and angiogenesis in vitro and in vivo.</p>