Limits...
Assessment of bystander killing-mediated therapy of malignant brain tumors using a multimodal imaging approach.

Leten C, Trekker J, Struys T, Dresselaers T, Gijsbers R, Vande Velde G, Lambrichts I, Van Der Linden A, Verfaillie CM, Himmelreich U - Stem Cell Res Ther (2015)

Bottom Line: Subsequently, ganciclovir (GCV) treatment was commenced and the fate of both the MAPCs and the tumor were followed by multimodal imaging (MRI and bioluminescence imaging).Noteworthy, in some phosphate-buffered saline-treated animals (33 %), a significant decrease in tumor size was seen compared to sham-operated animals, which could potentially also be caused by a synergistic effect of the immune-modulatory stem cells.This treatment could be followed and guided noninvasively in vivo by MRI and bioluminescence imaging.

View Article: PubMed Central - PubMed

Affiliation: Biomedical MRI, Department of Imaging and Pathology, KU Leuven, 3000, Leuven, Belgium. cindy.leten@gmail.com.

ABSTRACT

Introduction: In this study, we planned to assess if adult stem cell-based suicide gene therapy can efficiently eliminate glioblastoma cells in vivo. We investigated the therapeutic potential of mouse Oct4(-) bone marrow multipotent adult progenitor cells (mOct4(-) BM-MAPCs) in a mouse glioblastoma model, guided by multimodal in vivo imaging methods to identify therapeutic windows.

Methods: Magnetic resonance imaging (MRI) of animals, wherein 5 × 10(5) syngeneic enhanced green fluorescent protein-firefly luciferase-herpes simplex virus thymidine kinase (eGFP-fLuc-HSV-TK) expressing and superparamagnetic iron oxide nanoparticle labeled (1 % or 10 %) mOct4(-) BM-MAPCs were grafted in glioblastoma (GL261)-bearing animals, showed that labeled mOct4(-) BM-MAPCs were located in and in close proximity to the tumor. Subsequently, ganciclovir (GCV) treatment was commenced and the fate of both the MAPCs and the tumor were followed by multimodal imaging (MRI and bioluminescence imaging).

Results: In the majority of GCV-treated, but not phosphate-buffered saline-treated animals, a significant difference was found in mOct4(-) BM-MAPC viability and tumor size at the end of treatment. Noteworthy, in some phosphate-buffered saline-treated animals (33 %), a significant decrease in tumor size was seen compared to sham-operated animals, which could potentially also be caused by a synergistic effect of the immune-modulatory stem cells.

Conclusions: Suicide gene therapy using mOct4(-) BM-MAPCs as cellular carriers was effective in reducing the tumor size in the majority of the GCV-treated animals leading to a longer progression-free survival compared to sham-operated animals. This treatment could be followed and guided noninvasively in vivo by MRI and bioluminescence imaging. Noninvasive imaging is of particular interest for a rapid and efficient validation of stem cell-based therapeutic approaches for glioblastoma and hereby contributes to a better understanding and optimization of a promising therapeutic approach for glioblastoma patients.

No MeSH data available.


Related in: MedlinePlus

MRI and BLI images of one representative animal for each group. a Animals from the ganciclovir (GCV)-treated group displayed significantly smaller tumors at the end of GCV treatment compared to phosphate-buffered saline (PBS)-treated and sham-operated (SHAM) animals (*p < 0.05). Some substantial variability was noticed, however, between individual animals so subgroup analysis was performed (green bar: mOct4- BM-MAPC steretactical injection; red bar: treatment phase). b Representation of subgroup tumor development over time for sham-operated, PBS- and GCV-treated animals. No statistically significant differences could be found on day 14 and 16 between the different groups (green bar: mOct4- BM-MAPC steretactical injection; red bar: treatment phase). c Statistical analysis of the tumor volumes at the end of treatment (day 30) showed a statistically significant difference in tumor size between GCV responding (n = 11) animals and sham-operated (n = 5)/PBS-treated animals (n = 8). Furthermore, some GCV-treated animals (n = 7) did not respond to therapy whereas some PBS-treated (n = 4) animals also showed a reduced tumor size at the end of treatment. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. d mOct4− BM-MAPC viability measurements showed a reduced cell viability for the GCV but not the PBS treated group. *p < 0.05, ****p < 0.0001. e MR images of animals of different groups show a comparable tumor growth prior to mOct4− BM-MAPC injection on T2-weighted coronal MR images (upper row for each group) whereas there is little hypointense contrast visible on three-dimensional T2* MR images. In sham-operated animals this mild hypointense contrast was maintained as tumors grew larger although some increase in the hypointense voxel volume, due to the development of necrosis and bleedings, was observed. mOct4− BM-MAPC-injected animals (PBS and GCV) could be detected by three-dimensional T2* MRI (lower row for each group) on day 1 after injection. For animals which developed tumors, the hypointense voxels got more dispersed over time as tumors grew whereas mice responding to GCV treatment had little tumors where labeled mOct4− BM-MAPCs could still be detected at the end of GCV treatment. f BLI measurements showed a persistence of the BLI signal in PBS-treated animals indicating survival of the mOct4− BM-MAPCs whereas GCV-treated animals showed a decreased viability after GCV treatment. Sham operated animals were used as negative controls. g Histological overview images of brain sections from the respective animals of each treatment group stained with trichrome staining. d Day
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC4562202&req=5

Fig4: MRI and BLI images of one representative animal for each group. a Animals from the ganciclovir (GCV)-treated group displayed significantly smaller tumors at the end of GCV treatment compared to phosphate-buffered saline (PBS)-treated and sham-operated (SHAM) animals (*p < 0.05). Some substantial variability was noticed, however, between individual animals so subgroup analysis was performed (green bar: mOct4- BM-MAPC steretactical injection; red bar: treatment phase). b Representation of subgroup tumor development over time for sham-operated, PBS- and GCV-treated animals. No statistically significant differences could be found on day 14 and 16 between the different groups (green bar: mOct4- BM-MAPC steretactical injection; red bar: treatment phase). c Statistical analysis of the tumor volumes at the end of treatment (day 30) showed a statistically significant difference in tumor size between GCV responding (n = 11) animals and sham-operated (n = 5)/PBS-treated animals (n = 8). Furthermore, some GCV-treated animals (n = 7) did not respond to therapy whereas some PBS-treated (n = 4) animals also showed a reduced tumor size at the end of treatment. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. d mOct4− BM-MAPC viability measurements showed a reduced cell viability for the GCV but not the PBS treated group. *p < 0.05, ****p < 0.0001. e MR images of animals of different groups show a comparable tumor growth prior to mOct4− BM-MAPC injection on T2-weighted coronal MR images (upper row for each group) whereas there is little hypointense contrast visible on three-dimensional T2* MR images. In sham-operated animals this mild hypointense contrast was maintained as tumors grew larger although some increase in the hypointense voxel volume, due to the development of necrosis and bleedings, was observed. mOct4− BM-MAPC-injected animals (PBS and GCV) could be detected by three-dimensional T2* MRI (lower row for each group) on day 1 after injection. For animals which developed tumors, the hypointense voxels got more dispersed over time as tumors grew whereas mice responding to GCV treatment had little tumors where labeled mOct4− BM-MAPCs could still be detected at the end of GCV treatment. f BLI measurements showed a persistence of the BLI signal in PBS-treated animals indicating survival of the mOct4− BM-MAPCs whereas GCV-treated animals showed a decreased viability after GCV treatment. Sham operated animals were used as negative controls. g Histological overview images of brain sections from the respective animals of each treatment group stained with trichrome staining. d Day

Mentions: Stereotactical injection of 5x105 mOct4− BM-MAPCs, of which 10 % were ihSPIO labeled, into the striatum of GL261 tumor bearing C57BL6/j mice was performed. For this, GL261 tumors were allowed to expand for 14 days after which MRI was performed to ascertain tumor growth (Fig. 4 =d14). Subsequently, stem cells were stereotactically injected and MRI and BLI were performed on the following day (=d16) to ascertain stem cell location in and around the tumor. PBS or GCV (50 mg/kg) administration commenced on day 16 and continued for 14 consecutive days (i.e. until d30 following GL261 tumor induction). At d30 post GL261 injection, sham operated animals and some PBS treated animals started to develop grade 3 symptoms that were related to tumor growth, and needed to be sacrificed. MRI and BLI were performed weekly for the duration of the experiment for the assessment of tumor growth and stem cell viability.Fig. 4


Assessment of bystander killing-mediated therapy of malignant brain tumors using a multimodal imaging approach.

Leten C, Trekker J, Struys T, Dresselaers T, Gijsbers R, Vande Velde G, Lambrichts I, Van Der Linden A, Verfaillie CM, Himmelreich U - Stem Cell Res Ther (2015)

MRI and BLI images of one representative animal for each group. a Animals from the ganciclovir (GCV)-treated group displayed significantly smaller tumors at the end of GCV treatment compared to phosphate-buffered saline (PBS)-treated and sham-operated (SHAM) animals (*p < 0.05). Some substantial variability was noticed, however, between individual animals so subgroup analysis was performed (green bar: mOct4- BM-MAPC steretactical injection; red bar: treatment phase). b Representation of subgroup tumor development over time for sham-operated, PBS- and GCV-treated animals. No statistically significant differences could be found on day 14 and 16 between the different groups (green bar: mOct4- BM-MAPC steretactical injection; red bar: treatment phase). c Statistical analysis of the tumor volumes at the end of treatment (day 30) showed a statistically significant difference in tumor size between GCV responding (n = 11) animals and sham-operated (n = 5)/PBS-treated animals (n = 8). Furthermore, some GCV-treated animals (n = 7) did not respond to therapy whereas some PBS-treated (n = 4) animals also showed a reduced tumor size at the end of treatment. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. d mOct4− BM-MAPC viability measurements showed a reduced cell viability for the GCV but not the PBS treated group. *p < 0.05, ****p < 0.0001. e MR images of animals of different groups show a comparable tumor growth prior to mOct4− BM-MAPC injection on T2-weighted coronal MR images (upper row for each group) whereas there is little hypointense contrast visible on three-dimensional T2* MR images. In sham-operated animals this mild hypointense contrast was maintained as tumors grew larger although some increase in the hypointense voxel volume, due to the development of necrosis and bleedings, was observed. mOct4− BM-MAPC-injected animals (PBS and GCV) could be detected by three-dimensional T2* MRI (lower row for each group) on day 1 after injection. For animals which developed tumors, the hypointense voxels got more dispersed over time as tumors grew whereas mice responding to GCV treatment had little tumors where labeled mOct4− BM-MAPCs could still be detected at the end of GCV treatment. f BLI measurements showed a persistence of the BLI signal in PBS-treated animals indicating survival of the mOct4− BM-MAPCs whereas GCV-treated animals showed a decreased viability after GCV treatment. Sham operated animals were used as negative controls. g Histological overview images of brain sections from the respective animals of each treatment group stained with trichrome staining. d Day
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4562202&req=5

Fig4: MRI and BLI images of one representative animal for each group. a Animals from the ganciclovir (GCV)-treated group displayed significantly smaller tumors at the end of GCV treatment compared to phosphate-buffered saline (PBS)-treated and sham-operated (SHAM) animals (*p < 0.05). Some substantial variability was noticed, however, between individual animals so subgroup analysis was performed (green bar: mOct4- BM-MAPC steretactical injection; red bar: treatment phase). b Representation of subgroup tumor development over time for sham-operated, PBS- and GCV-treated animals. No statistically significant differences could be found on day 14 and 16 between the different groups (green bar: mOct4- BM-MAPC steretactical injection; red bar: treatment phase). c Statistical analysis of the tumor volumes at the end of treatment (day 30) showed a statistically significant difference in tumor size between GCV responding (n = 11) animals and sham-operated (n = 5)/PBS-treated animals (n = 8). Furthermore, some GCV-treated animals (n = 7) did not respond to therapy whereas some PBS-treated (n = 4) animals also showed a reduced tumor size at the end of treatment. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. d mOct4− BM-MAPC viability measurements showed a reduced cell viability for the GCV but not the PBS treated group. *p < 0.05, ****p < 0.0001. e MR images of animals of different groups show a comparable tumor growth prior to mOct4− BM-MAPC injection on T2-weighted coronal MR images (upper row for each group) whereas there is little hypointense contrast visible on three-dimensional T2* MR images. In sham-operated animals this mild hypointense contrast was maintained as tumors grew larger although some increase in the hypointense voxel volume, due to the development of necrosis and bleedings, was observed. mOct4− BM-MAPC-injected animals (PBS and GCV) could be detected by three-dimensional T2* MRI (lower row for each group) on day 1 after injection. For animals which developed tumors, the hypointense voxels got more dispersed over time as tumors grew whereas mice responding to GCV treatment had little tumors where labeled mOct4− BM-MAPCs could still be detected at the end of GCV treatment. f BLI measurements showed a persistence of the BLI signal in PBS-treated animals indicating survival of the mOct4− BM-MAPCs whereas GCV-treated animals showed a decreased viability after GCV treatment. Sham operated animals were used as negative controls. g Histological overview images of brain sections from the respective animals of each treatment group stained with trichrome staining. d Day
Mentions: Stereotactical injection of 5x105 mOct4− BM-MAPCs, of which 10 % were ihSPIO labeled, into the striatum of GL261 tumor bearing C57BL6/j mice was performed. For this, GL261 tumors were allowed to expand for 14 days after which MRI was performed to ascertain tumor growth (Fig. 4 =d14). Subsequently, stem cells were stereotactically injected and MRI and BLI were performed on the following day (=d16) to ascertain stem cell location in and around the tumor. PBS or GCV (50 mg/kg) administration commenced on day 16 and continued for 14 consecutive days (i.e. until d30 following GL261 tumor induction). At d30 post GL261 injection, sham operated animals and some PBS treated animals started to develop grade 3 symptoms that were related to tumor growth, and needed to be sacrificed. MRI and BLI were performed weekly for the duration of the experiment for the assessment of tumor growth and stem cell viability.Fig. 4

Bottom Line: Subsequently, ganciclovir (GCV) treatment was commenced and the fate of both the MAPCs and the tumor were followed by multimodal imaging (MRI and bioluminescence imaging).Noteworthy, in some phosphate-buffered saline-treated animals (33 %), a significant decrease in tumor size was seen compared to sham-operated animals, which could potentially also be caused by a synergistic effect of the immune-modulatory stem cells.This treatment could be followed and guided noninvasively in vivo by MRI and bioluminescence imaging.

View Article: PubMed Central - PubMed

Affiliation: Biomedical MRI, Department of Imaging and Pathology, KU Leuven, 3000, Leuven, Belgium. cindy.leten@gmail.com.

ABSTRACT

Introduction: In this study, we planned to assess if adult stem cell-based suicide gene therapy can efficiently eliminate glioblastoma cells in vivo. We investigated the therapeutic potential of mouse Oct4(-) bone marrow multipotent adult progenitor cells (mOct4(-) BM-MAPCs) in a mouse glioblastoma model, guided by multimodal in vivo imaging methods to identify therapeutic windows.

Methods: Magnetic resonance imaging (MRI) of animals, wherein 5 × 10(5) syngeneic enhanced green fluorescent protein-firefly luciferase-herpes simplex virus thymidine kinase (eGFP-fLuc-HSV-TK) expressing and superparamagnetic iron oxide nanoparticle labeled (1 % or 10 %) mOct4(-) BM-MAPCs were grafted in glioblastoma (GL261)-bearing animals, showed that labeled mOct4(-) BM-MAPCs were located in and in close proximity to the tumor. Subsequently, ganciclovir (GCV) treatment was commenced and the fate of both the MAPCs and the tumor were followed by multimodal imaging (MRI and bioluminescence imaging).

Results: In the majority of GCV-treated, but not phosphate-buffered saline-treated animals, a significant difference was found in mOct4(-) BM-MAPC viability and tumor size at the end of treatment. Noteworthy, in some phosphate-buffered saline-treated animals (33 %), a significant decrease in tumor size was seen compared to sham-operated animals, which could potentially also be caused by a synergistic effect of the immune-modulatory stem cells.

Conclusions: Suicide gene therapy using mOct4(-) BM-MAPCs as cellular carriers was effective in reducing the tumor size in the majority of the GCV-treated animals leading to a longer progression-free survival compared to sham-operated animals. This treatment could be followed and guided noninvasively in vivo by MRI and bioluminescence imaging. Noninvasive imaging is of particular interest for a rapid and efficient validation of stem cell-based therapeutic approaches for glioblastoma and hereby contributes to a better understanding and optimization of a promising therapeutic approach for glioblastoma patients.

No MeSH data available.


Related in: MedlinePlus