Effect of LiCl on Iodine Kinetics in Thyroid Cancer Cell Lines Transduced by Recombinant Adenovirus Containing Sodium Iodide Symporter(NIS) Gene / 대한내분비학회지

BACKGROUND: Lithium is known to increase the retention of iodide in the thyroid gland, or in well differentiated thyroid cancer tissue. The effects of lithium on the function of the sodium iodide symporter (NIS) protein, especially when the lithium is increased in the retention of iodide in NIS-producing cells, the effect of lithium, on the kinetics of undifferentiated thyroid cancer cells transduced by a recombinant adenovirus containing the NIS gene, were checked. METHOD: Human NIS cDNA was inserted into pAxCAwt, a recombinant adenoviral cosmid vector, where the E1 & E2 genes have been deleted, making Rad-hNIS, which was propagated in 293 cells. The iodide uptake was evaluated by the 125I uptake assay in the undifferentiated thyroid cancer cells, ARO, FRO and NPA, following the infection with Rad-hNIS (1 or 10 MOI) in the presence, or absence, of LiCl at optimized concentrations. The iodide efflux was evaluated by the 125I efflux assay, for 1 hour, in the same cells expressing the NIS in the presence, or absence, of LiCl. Similar experiments were performed in the normal thyroid cell line, FRTL-5, cultured in 6H5 media. RESULTS: LiCl, at concentrations over 1.0mM, caused a significant decrease in the cell viability, as evaluated by trypan blue dye exclusion, in a dose dependent manner. When infected with Rad-hNIS, the iodide uptake was not affected by the LiCl in the ARO or NPA cells. However, LiCl(0.1and 1.0mM) increased the iodide uptake by 50 to 100%(vs. control) in the Rad-hNIS transduced FRO cells. In the Rad-hNIS transduced FRO cells, the iodide was released rapidly from the cells, with only 20.7+/-4.8% of the iodide uptake remaining at 1 hour, which was no different in the presence of LiCl (24.5+/-7.9%). The iodide efflux was not affected by the LiCl in the FRTL-5 cells cultured in the presence of TSH. CONCLUSION: These results suggest that the lithium-induced iodide retention in the thyroid gland, or in well differentiated thyroid cancer tissue, is not caused by the effect of the lithium on the NIS function, or the function of proteins or channels, involved in iodide transport via cell membranes. Although the iodide uptake can be markedly increased by the expression of NIS, with the transduction of Rad-hNIS, in undifferentiated thyroid cancer cells, the iodide taken up is rapidly released from the cells. A method for inducing the iodide retention in the cell should be elucidated in order to render the NIS gene therapy effective.

Evaluation of E1B-mutant Replicating Adenoviruses for Cancer Gene Therapy / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Gene-attenuated replication-competent adenoviruses are emerging as a promising new modality for the treatment of cancer. In an effort to continually improve upon cancer gene therapy, we have modified gene- attenuated replication-competent adenoviruses so as to cause them to replicate efficiently and lyse the infected cancer cells more effectively. MATERIALS AND METHODS: We modified the E1 region of the adenovirus (Ad) systematically, generating Ad-deltaE1B19, Ad-deltaE1B55, Ad-deltaE1B19/55, and Ad-WT. The cytopathic effects (CPE) and viral replication of these four gene modified adenoviruses were compared, and the morphology and DNA fragmentation of the infected cells was evaluated. RESULTS: Among the constructed adenoviruses, E1B 19kD-inactivated adenovirus (Ad-deltaE1B19) was the most potent, inducing the largest-sized plaques and markedCPE. Moreover, cells infected with Ad-deltaE1B19 showed complete cell lysis with disintegrated cellular structure whereas cells infected with Ad-WT maintained intact cellular and nuclear membrane with properly structured organelles. TUNEL assay was also used to monitor DNA integrity, and a more profound induction of apoptosis was observed in the Ad-deltaE1B19 infected cells in comparison to wild type adenovirus infected cells. CONCLUSION: We demonstrate that the inactivation of the E1B19kD gene in a replicating adenovirus leads to increased CPE, rapid viral release, improved cell-to-cell viral spread and increased induction of apoptosis.

Molecular Analysis of Protease and Reverse Transcriptase in an AIDS Patient with HAART - Failure

No abstract available.

Sequence Varation of 5(1) Nontranslating Region of Enterovirus Isolated from Patients with Aseptic Meningitis

No abstract available.

Enhanced Effect of Iodide - Uptake in Thyroid Carcinoma Cells by Infecting Adenovirus - Human Sodium Iodide Symporter (Ad - hNIS) / 대한내분비학회지

BACKGROUND: The sodium-iodide-symporter (NIS) is a plasma membrane glycoprotein with 13 putative transmembrane domains, which is responsible for concentrating iodide into the thyroid by an active transport and provides the mechanism for radioactive-iodine (RAI) therapy for thyroid cancer. However, undifferentiated thyroid cancers and about 2050% of differentiated thyroid cancers do not take up the RAI at therapeutic dose. The NIS has been cloned from rat and human (hNIS) and characterized recently. In an attempt to develop a new therapeutic strategy using hNIS gene for improving the efficacy of RAI therapy in thyroid cancers, we have constructed a recombinant adenovirus encoding the hNIS (Ad-hNIS) and tested its function by an iodide uptake by infecting human thyroid cancer cells. METHODS: RT-PCR was performed to measure an intrinsic hNIS expression in thyroid cancer cell lines, such as NPA, FRO and ARO. To generate the hNIS adenovirus, hNIS cDNA was isolated and ligated into Swa I site of cosmid shuttle vector (pAxCAwt). We have produced recombinant adenovirus by co-transfecting the cosmid with DNA-TPC to 293 cell line. Adenovirus that express (beta-Galactosidase (LacZ) was also prepared by the similar strategy. Adenovirus infection efficiency was measured in three thyroid cancer cell lines. Finally, 24 hours after infection of ad-hNIS into the cells, I125-uptake was measured. RESULTS: Endogenous hNIS expression was detected only in FRO cells but not in NPA, ARO and Hela cells by RT-PCR. X-Gal staining after infection of Ad-LacZ to thyroid cancer cell (NPA, ARO, FRO) showed that an infection rate in ARO cells was 98.5+0.5%, 97.0+0.2% in FRO cells and 75.5+5.0% in NPA cells. We selected ARO cells for the infection of Ad-hNIS due to the highest infection efficiency and the absence of endogenous hNIS expression. When ARO cells were infected with the ad-hNIS, I125 uptake was increased 504+6.4%. CONCLUSION: Overexpression of hNIS gene in thyroid cancer cells elicited over 5 fold increase in I-uptake, suggesting that the Ad-hNIS infection to the thyroid cancer cells may improve the efficiency of radioactive iodine therapy.

Effects of Herpes Simplex Virus - Thymidine Kinase Gene Transduction into the Hepatocellular Carcinoma Cell Lines Using the Retrovirus on Ganciclovir Cytoxicity / 대한암학회지

PURPOSE: Hepatocellular carcinoma (HCC) is one of the most common malignancy with high mortality in Korea. A new therapeutic modality such as gene therapy is necessary to improve the prognosis of hepatoma patients. Therefore we investigated the preclinical significance of Herpes simplex virus - thymidine kinase/ganciclovir (HSV-tk/GCV) gene therapy model using the retroviral vector for HCC cell lines. MATERIALS AND METHODS: LNC/HSV-tk retroviral vector and PA317/LNC/HSV-tk pro- ducer cell line were constructed. HSV-tk transduced HCC cells using the LNC/HSV-tk retrovirus were selected by the G418 containing media. In vitro GCV sensitivity test of the HCC cells was performed by MTT assay. To evaluate in vivo GCV sensitivity, GCV was intraperitoneally injected after subcutaneous administration of HCC cells into each flank of the nude mouse. RESULTS: HSV-tk gene transduction and expression in HCC cells were confirmed by RT-PCR. HSV-tk transduced HCC cell lines (SK-Hepl/HSV-tk and Hep-3B/HSV-tk) showed the marked GCV sensitivity comparing with the parental cell lines (SK-Hepl and Hep-3B) by MTT assay (p<0.001). The MTT test revealed that SK-Hepl/HSV-tk cells were more sensitive to GCV compare with that of Hep-3B/H5V-tk cells, and the parent cell line showed minimal growth suppression by the GCV treatment. In 12 nude mice received tumor cell mixtures of Hep-3B and Hep-3B/HSV-tk cells which contained more than 50% of HSV-tk transduced cells, the tumor was not developed in ll mice by the intraperitoneal administration of GCV. The tumors developed in 1 of 6 mice and 5 of 6 mice when mixtures contained 30% and 10% of HSV-tk transduced cells, respectively. Five mice out of 6 mice received inoculum containing the mixtures of 70% and 50% of HSV-tk transduced cells into each flank survived more than 6 month after HSV-tk/GCV treatment. Conelusion: HSV-tk gene transduced HCC cells showed the enhanced sensitivity to GCV. In nude mice HSV-tk/GCV strategy for HCC seemed to be more effective when tumor cell inoculum contained more than 30% of HSV-tk transduced HCC cells.