Limits...
Therapeutic properties of a vector carrying the HSV thymidine kinase and GM-CSF genes and delivered as a complex with a cationic copolymer.

Alekseenko IV, Snezhkov EV, Chernov IP, Pleshkan VV, Potapov VK, Sass AV, Monastyrskaya GS, Kopantzev EP, Vinogradova TV, Khramtsov YV, Ulasov AV, Rosenkranz AA, Sobolev AS, Bezborodova OA, Plyutinskaya AD, Nemtsova ER, Yakubovskaya RI, Sverdlov ED - J Transl Med (2015)

Bottom Line: We tried to overcome these constraints through a combination of suicide gene therapy with immunomodulating therapy.The system HSVtk-GM-CSF/PEI-PEG was tested in vitro in various mouse and human cell lines, ex vivo and in vivo using mouse models.Our data indicate that combined suicide and cytokine gene therapy may provide a powerful approach for the treatment of solid tumors and their metastases.

View Article: PubMed Central - PubMed

Affiliation: Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya 16/10, Moscow, 117997, Russia. irina.alekseenko@mail.ru.

ABSTRACT

Background: Gene-directed enzyme prodrug therapy (GDEPT) represents a technology to improve drug selectivity for cancer cells. It consists of delivery into tumor cells of a suicide gene responsible for in situ conversion of a prodrug into cytotoxic metabolites. Major limitations of GDEPT that hinder its clinical application include inefficient delivery into cancer cells and poor prodrug activation by suicide enzymes. We tried to overcome these constraints through a combination of suicide gene therapy with immunomodulating therapy. Viral vectors dominate in present-day GDEPT clinical trials due to efficient transfection and production of therapeutic genes. However, safety concerns associated with severe immune and inflammatory responses as well as high cost of the production of therapeutic viruses can limit therapeutic use of virus-based therapeutics. We tried to overcome this problem by using a simple nonviral delivery system.

Methods: We studied the antitumor efficacy of a PEI (polyethylenimine)-PEG (polyethylene glycol) copolymer carrying the HSVtk gene combined in one vector with granulocyte-macrophage colony-stimulating factor (GM-CSF) cDNA. The system HSVtk-GM-CSF/PEI-PEG was tested in vitro in various mouse and human cell lines, ex vivo and in vivo using mouse models.

Results: We showed that the HSVtk-GM-CSF/PEI-PEG system effectively inhibited the growth of transplanted human and mouse tumors, suppressed metastasis and increased animal lifespan.

Conclusions: We demonstrated that appreciable tumor shrinkage and metastasis inhibition could be achieved with a simple and low toxic chemical carrier - a PEI-PEG copolymer. Our data indicate that combined suicide and cytokine gene therapy may provide a powerful approach for the treatment of solid tumors and their metastases.

No MeSH data available.


Related in: MedlinePlus

Effect ofex vivotransformation of LLC cells with the TK and TKmGM constructs combined with administration of GCV on A) tumor growth rate, and B) animal lifespan after transplantation of the transfected cells into C57Bl/6 mice. The data represent mean values for treatment groups of ten animals and control groups of six animals. We studied 6 groups of mice: two control groups (K/GCV and K/PBS) inoculated with non-transfected cells; two experimental groups (TK/GCV and TK/PBS) inoculated with LLC cells transfected with TK; and two experimental groups (TKmGM/GCV and TKmGM/PBS) inoculated with LLC cells transfected with TKmGM using LFA. The animals of groups К/GCV, ТK/GCV and TKmGM/GCV received intraperitoneal injections of ganciclovir in a dose of 75 mg/kg twice a day for 10 days. The animals of groups К/PBS, ТK/PBS and TKmGM/PBS received phosphate buffered saline (PBS) as a placebo instead of GCV. Starting from day 6 after transplantation, we measured the volume of developed tumors. The euthanasia criterion was the tumor volume that exceeded 2000 mm3. A) Tumor volume (in mm3, Y-axis) versus time since cell transplantation (X-axis). Mean ± SEM values are shown. B) Survival period of mice after transplantation of the transfected and non-transfected LLC cells.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC4359447&req=5

Fig2: Effect ofex vivotransformation of LLC cells with the TK and TKmGM constructs combined with administration of GCV on A) tumor growth rate, and B) animal lifespan after transplantation of the transfected cells into C57Bl/6 mice. The data represent mean values for treatment groups of ten animals and control groups of six animals. We studied 6 groups of mice: two control groups (K/GCV and K/PBS) inoculated with non-transfected cells; two experimental groups (TK/GCV and TK/PBS) inoculated with LLC cells transfected with TK; and two experimental groups (TKmGM/GCV and TKmGM/PBS) inoculated with LLC cells transfected with TKmGM using LFA. The animals of groups К/GCV, ТK/GCV and TKmGM/GCV received intraperitoneal injections of ganciclovir in a dose of 75 mg/kg twice a day for 10 days. The animals of groups К/PBS, ТK/PBS and TKmGM/PBS received phosphate buffered saline (PBS) as a placebo instead of GCV. Starting from day 6 after transplantation, we measured the volume of developed tumors. The euthanasia criterion was the tumor volume that exceeded 2000 mm3. A) Tumor volume (in mm3, Y-axis) versus time since cell transplantation (X-axis). Mean ± SEM values are shown. B) Survival period of mice after transplantation of the transfected and non-transfected LLC cells.

Mentions: As seen from Figure 2A, on day 18 of the experiment (the last day when all animals were still alive), the animals inoculated with the TKmGM/GCV or TK/GCV system showed no indications of tumor development. The tumor growth in the group of animals inoculated with the TKmGM/PBS combination was markedly slower than that in the TK/PBS group or control groups, and the difference was statistically significant (p < 0.05). Since the animals inoculated with TKmGM/PBS or TK/PBS received phosphate buffered saline (PBS) instead of GCV, the suppression of tumor growth in the TKmGM/PBS group was most probably due to the presence of the GM-CSF gene. On day 18 of the experiment, the mean tumor volume in the K/GCV control group exceeded that in the K/PBS control group, however, the difference was not statistically significant (p = 0.262).Figure 2


Therapeutic properties of a vector carrying the HSV thymidine kinase and GM-CSF genes and delivered as a complex with a cationic copolymer.

Alekseenko IV, Snezhkov EV, Chernov IP, Pleshkan VV, Potapov VK, Sass AV, Monastyrskaya GS, Kopantzev EP, Vinogradova TV, Khramtsov YV, Ulasov AV, Rosenkranz AA, Sobolev AS, Bezborodova OA, Plyutinskaya AD, Nemtsova ER, Yakubovskaya RI, Sverdlov ED - J Transl Med (2015)

Effect ofex vivotransformation of LLC cells with the TK and TKmGM constructs combined with administration of GCV on A) tumor growth rate, and B) animal lifespan after transplantation of the transfected cells into C57Bl/6 mice. The data represent mean values for treatment groups of ten animals and control groups of six animals. We studied 6 groups of mice: two control groups (K/GCV and K/PBS) inoculated with non-transfected cells; two experimental groups (TK/GCV and TK/PBS) inoculated with LLC cells transfected with TK; and two experimental groups (TKmGM/GCV and TKmGM/PBS) inoculated with LLC cells transfected with TKmGM using LFA. The animals of groups К/GCV, ТK/GCV and TKmGM/GCV received intraperitoneal injections of ganciclovir in a dose of 75 mg/kg twice a day for 10 days. The animals of groups К/PBS, ТK/PBS and TKmGM/PBS received phosphate buffered saline (PBS) as a placebo instead of GCV. Starting from day 6 after transplantation, we measured the volume of developed tumors. The euthanasia criterion was the tumor volume that exceeded 2000 mm3. A) Tumor volume (in mm3, Y-axis) versus time since cell transplantation (X-axis). Mean ± SEM values are shown. B) Survival period of mice after transplantation of the transfected and non-transfected LLC cells.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4359447&req=5

Fig2: Effect ofex vivotransformation of LLC cells with the TK and TKmGM constructs combined with administration of GCV on A) tumor growth rate, and B) animal lifespan after transplantation of the transfected cells into C57Bl/6 mice. The data represent mean values for treatment groups of ten animals and control groups of six animals. We studied 6 groups of mice: two control groups (K/GCV and K/PBS) inoculated with non-transfected cells; two experimental groups (TK/GCV and TK/PBS) inoculated with LLC cells transfected with TK; and two experimental groups (TKmGM/GCV and TKmGM/PBS) inoculated with LLC cells transfected with TKmGM using LFA. The animals of groups К/GCV, ТK/GCV and TKmGM/GCV received intraperitoneal injections of ganciclovir in a dose of 75 mg/kg twice a day for 10 days. The animals of groups К/PBS, ТK/PBS and TKmGM/PBS received phosphate buffered saline (PBS) as a placebo instead of GCV. Starting from day 6 after transplantation, we measured the volume of developed tumors. The euthanasia criterion was the tumor volume that exceeded 2000 mm3. A) Tumor volume (in mm3, Y-axis) versus time since cell transplantation (X-axis). Mean ± SEM values are shown. B) Survival period of mice after transplantation of the transfected and non-transfected LLC cells.
Mentions: As seen from Figure 2A, on day 18 of the experiment (the last day when all animals were still alive), the animals inoculated with the TKmGM/GCV or TK/GCV system showed no indications of tumor development. The tumor growth in the group of animals inoculated with the TKmGM/PBS combination was markedly slower than that in the TK/PBS group or control groups, and the difference was statistically significant (p < 0.05). Since the animals inoculated with TKmGM/PBS or TK/PBS received phosphate buffered saline (PBS) instead of GCV, the suppression of tumor growth in the TKmGM/PBS group was most probably due to the presence of the GM-CSF gene. On day 18 of the experiment, the mean tumor volume in the K/GCV control group exceeded that in the K/PBS control group, however, the difference was not statistically significant (p = 0.262).Figure 2

Bottom Line: We tried to overcome these constraints through a combination of suicide gene therapy with immunomodulating therapy.The system HSVtk-GM-CSF/PEI-PEG was tested in vitro in various mouse and human cell lines, ex vivo and in vivo using mouse models.Our data indicate that combined suicide and cytokine gene therapy may provide a powerful approach for the treatment of solid tumors and their metastases.

View Article: PubMed Central - PubMed

Affiliation: Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya 16/10, Moscow, 117997, Russia. irina.alekseenko@mail.ru.

ABSTRACT

Background: Gene-directed enzyme prodrug therapy (GDEPT) represents a technology to improve drug selectivity for cancer cells. It consists of delivery into tumor cells of a suicide gene responsible for in situ conversion of a prodrug into cytotoxic metabolites. Major limitations of GDEPT that hinder its clinical application include inefficient delivery into cancer cells and poor prodrug activation by suicide enzymes. We tried to overcome these constraints through a combination of suicide gene therapy with immunomodulating therapy. Viral vectors dominate in present-day GDEPT clinical trials due to efficient transfection and production of therapeutic genes. However, safety concerns associated with severe immune and inflammatory responses as well as high cost of the production of therapeutic viruses can limit therapeutic use of virus-based therapeutics. We tried to overcome this problem by using a simple nonviral delivery system.

Methods: We studied the antitumor efficacy of a PEI (polyethylenimine)-PEG (polyethylene glycol) copolymer carrying the HSVtk gene combined in one vector with granulocyte-macrophage colony-stimulating factor (GM-CSF) cDNA. The system HSVtk-GM-CSF/PEI-PEG was tested in vitro in various mouse and human cell lines, ex vivo and in vivo using mouse models.

Results: We showed that the HSVtk-GM-CSF/PEI-PEG system effectively inhibited the growth of transplanted human and mouse tumors, suppressed metastasis and increased animal lifespan.

Conclusions: We demonstrated that appreciable tumor shrinkage and metastasis inhibition could be achieved with a simple and low toxic chemical carrier - a PEI-PEG copolymer. Our data indicate that combined suicide and cytokine gene therapy may provide a powerful approach for the treatment of solid tumors and their metastases.

No MeSH data available.


Related in: MedlinePlus