Limits...
A probasin promoter, conditionally replicating adenovirus that expresses the sodium iodide symporter (NIS) for radiovirotherapy of prostate cancer.

Trujillo MA, Oneal MJ, McDonough S, Qin R, Morris JC - Gene Ther. (2010)

Bottom Line: Conversely, the prostate cancer cell line PC-3 (androgen receptor negative) and the pancreatic cancer cell line Panc-1 were refractory to the viral cytopathic effect and did not support viral replication.Radioiodine uptake was readily measurable in LnCaP cells infected with Ad5PB_RSV-NIS 24 h post-infection, confirming NIS expression.Administration of therapeutic ¹³¹I after virus injection significantly increased survival probability in mice carrying xenografted LnCaP tumors compared with virotherapy alone.

View Article: PubMed Central - PubMed

Affiliation: Department of Internal Medicine, Division of Endocrinology, Diabetes, Metabolism, Nutrition, Mayo Clinic, Rochester, MN 55905, USA.

ABSTRACT
The sodium iodide symporter (NIS) directs the uptake and concentration of iodide in thyroid cells. We have extended the use of NIS-mediated radioiodine therapy to other types of cancer, we transferred and expressed the NIS gene into prostate, colon and breast cancer cells using adenoviral vectors. To improve vector efficiency we have developed a conditionally replicating adenovirus (CRAd) in which the E1a gene is driven by the prostate-specific promoter, Probasin and the cassette RSV promoter human NIScDNA-bGH polyA replaces the E3 region (CRAd Ad5PB_RSV-NIS). In vitro infection of the prostate cancer cell line LnCaP resulted in virus replication, cytolysis and release of infective viral particles. Conversely, the prostate cancer cell line PC-3 (androgen receptor negative) and the pancreatic cancer cell line Panc-1 were refractory to the viral cytopathic effect and did not support viral replication. Radioiodine uptake was readily measurable in LnCaP cells infected with Ad5PB_RSV-NIS 24 h post-infection, confirming NIS expression. In vivo, LnCaP tumor xenografts in nude-mice injected intratumorally with Ad5PB_RSV_NIS CRAd expressed NIS actively as evidenced by ⁹⁹Tc uptake and imaging. Administration of therapeutic ¹³¹I after virus injection significantly increased survival probability in mice carrying xenografted LnCaP tumors compared with virotherapy alone. These data indicate that Ad5PB_RSV_NIS replication is stringently restricted to androgen-positive prostate cancer cells and results in effective NIS expression and uptake of radioiodine. This construct may allow multimodal therapy, combining cytolytic virotherapy with radioiodine treatment, to be developed as a novel treatment for prostate cancer.

Show MeSH

Related in: MedlinePlus

Kinetics of NIS-mediated Radioiodine UptakeLnCaP and Panc-1 cells were infected at MOI 20 with the CRAd or the non replicating virus Ad5PB-NIS in which the E1A region is replaced by the transcription unit PB-NIS-SV40 PolyA. 125I uptake was measured daily.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC2914818&req=5

Figure 3: Kinetics of NIS-mediated Radioiodine UptakeLnCaP and Panc-1 cells were infected at MOI 20 with the CRAd or the non replicating virus Ad5PB-NIS in which the E1A region is replaced by the transcription unit PB-NIS-SV40 PolyA. 125I uptake was measured daily.

Mentions: The next task was to investigate NIS expression induced by the construct, which is driven by the ubiquitous RSV promoter. CRAd-mediated NIS expression, in prostate and pancreatic cell lines which do not naturally supports NIS expression, was examined by Western Blot (Not shown) and by NIS-mediated radioiodine uptake (Figure 3). Ad5PB_RSV-NIS infected LnCaP cells kinetics of iodine uptake at MOI 20 showed a maximum at 24 hours post-infection followed by a sharp decrease (Figure 3A). Radioiodine uptake was inhibited by KClO4, a well known inhibitor of NIS activity indicting that it was specific for NIS expression 5. These data indicate that an optimal window in time for NIS expression in permissive cells exists, after which NIS expression declines due to virus replication and induction of CPE. In support of this interpretation, cells infected with the non-replicating virus Ad5PB-RSV, in which the NIS gene under the control of the PB promoter is inserted at the E1A region, maintained radioiodine uptake for three days (Figure 3B). Additionally, Panc-1 cells, which are refractory to Ad5PB_RSV-NIS killing, also supported radioiodine uptake mediated by RSV-driven NIS for three days (Figure 3C) but, as expected, did not express PB-driven NIS (Figure 3D).


A probasin promoter, conditionally replicating adenovirus that expresses the sodium iodide symporter (NIS) for radiovirotherapy of prostate cancer.

Trujillo MA, Oneal MJ, McDonough S, Qin R, Morris JC - Gene Ther. (2010)

Kinetics of NIS-mediated Radioiodine UptakeLnCaP and Panc-1 cells were infected at MOI 20 with the CRAd or the non replicating virus Ad5PB-NIS in which the E1A region is replaced by the transcription unit PB-NIS-SV40 PolyA. 125I uptake was measured daily.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2914818&req=5

Figure 3: Kinetics of NIS-mediated Radioiodine UptakeLnCaP and Panc-1 cells were infected at MOI 20 with the CRAd or the non replicating virus Ad5PB-NIS in which the E1A region is replaced by the transcription unit PB-NIS-SV40 PolyA. 125I uptake was measured daily.
Mentions: The next task was to investigate NIS expression induced by the construct, which is driven by the ubiquitous RSV promoter. CRAd-mediated NIS expression, in prostate and pancreatic cell lines which do not naturally supports NIS expression, was examined by Western Blot (Not shown) and by NIS-mediated radioiodine uptake (Figure 3). Ad5PB_RSV-NIS infected LnCaP cells kinetics of iodine uptake at MOI 20 showed a maximum at 24 hours post-infection followed by a sharp decrease (Figure 3A). Radioiodine uptake was inhibited by KClO4, a well known inhibitor of NIS activity indicting that it was specific for NIS expression 5. These data indicate that an optimal window in time for NIS expression in permissive cells exists, after which NIS expression declines due to virus replication and induction of CPE. In support of this interpretation, cells infected with the non-replicating virus Ad5PB-RSV, in which the NIS gene under the control of the PB promoter is inserted at the E1A region, maintained radioiodine uptake for three days (Figure 3B). Additionally, Panc-1 cells, which are refractory to Ad5PB_RSV-NIS killing, also supported radioiodine uptake mediated by RSV-driven NIS for three days (Figure 3C) but, as expected, did not express PB-driven NIS (Figure 3D).

Bottom Line: Conversely, the prostate cancer cell line PC-3 (androgen receptor negative) and the pancreatic cancer cell line Panc-1 were refractory to the viral cytopathic effect and did not support viral replication.Radioiodine uptake was readily measurable in LnCaP cells infected with Ad5PB_RSV-NIS 24 h post-infection, confirming NIS expression.Administration of therapeutic ¹³¹I after virus injection significantly increased survival probability in mice carrying xenografted LnCaP tumors compared with virotherapy alone.

View Article: PubMed Central - PubMed

Affiliation: Department of Internal Medicine, Division of Endocrinology, Diabetes, Metabolism, Nutrition, Mayo Clinic, Rochester, MN 55905, USA.

ABSTRACT
The sodium iodide symporter (NIS) directs the uptake and concentration of iodide in thyroid cells. We have extended the use of NIS-mediated radioiodine therapy to other types of cancer, we transferred and expressed the NIS gene into prostate, colon and breast cancer cells using adenoviral vectors. To improve vector efficiency we have developed a conditionally replicating adenovirus (CRAd) in which the E1a gene is driven by the prostate-specific promoter, Probasin and the cassette RSV promoter human NIScDNA-bGH polyA replaces the E3 region (CRAd Ad5PB_RSV-NIS). In vitro infection of the prostate cancer cell line LnCaP resulted in virus replication, cytolysis and release of infective viral particles. Conversely, the prostate cancer cell line PC-3 (androgen receptor negative) and the pancreatic cancer cell line Panc-1 were refractory to the viral cytopathic effect and did not support viral replication. Radioiodine uptake was readily measurable in LnCaP cells infected with Ad5PB_RSV-NIS 24 h post-infection, confirming NIS expression. In vivo, LnCaP tumor xenografts in nude-mice injected intratumorally with Ad5PB_RSV_NIS CRAd expressed NIS actively as evidenced by ⁹⁹Tc uptake and imaging. Administration of therapeutic ¹³¹I after virus injection significantly increased survival probability in mice carrying xenografted LnCaP tumors compared with virotherapy alone. These data indicate that Ad5PB_RSV_NIS replication is stringently restricted to androgen-positive prostate cancer cells and results in effective NIS expression and uptake of radioiodine. This construct may allow multimodal therapy, combining cytolytic virotherapy with radioiodine treatment, to be developed as a novel treatment for prostate cancer.

Show MeSH
Related in: MedlinePlus