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Real-time monitoring of tumorigenesis, dissemination, & drug response in a preclinical model of lymphangioleiomyomatosis/tuberous sclerosis complex.

Liu F, Lunsford EP, Tong J, Ashitate Y, Gibbs SL, Yu J, Choi HS, Henske EP, Frangioni JV - PLoS ONE (2012)

Bottom Line: Surprisingly, TSC2-deficient cells administered intratracheally resulted in rapid dissemination to lymph node basins throughout the body, and histopathological changes in the lung consistent with LAM.Estrogen was found to be permissive for tumor growth and dissemination.We generated homogeneous NIS/GFP co-expressing TSC2-deficient, patient-derived cells that can proliferate and migrate in vivo after intratracheal instillation.

View Article: PubMed Central - PubMed

Affiliation: Division of Hematology/Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America.

ABSTRACT

Background: TSC2-deficient cells can proliferate in the lungs, kidneys, and other organs causing devastating progressive multisystem disorders such as lymphangioleiomyomatosis (LAM) and tuberous sclerosis complex (TSC). Preclinical models utilizing LAM patient-derived cells have been difficult to establish. We developed a novel animal model system to study the molecular mechanisms of TSC/LAM pathogenesis and tumorigenesis and provide a platform for drug testing.

Methods and findings: TSC2-deficient human cells, derived from the angiomyolipoma of a LAM patient, were engineered to co-express both sodium-iodide symporter (NIS) and green fluorescent protein (GFP). Cells were inoculated intraparenchymally, intravenously, or intratracheally into athymic NCr nu/nu mice and cells were tracked and quantified using single photon emission computed tomography (SPECT) and computed tomography (CT). Surprisingly, TSC2-deficient cells administered intratracheally resulted in rapid dissemination to lymph node basins throughout the body, and histopathological changes in the lung consistent with LAM. Estrogen was found to be permissive for tumor growth and dissemination. Rapamycin inhibited tumor growth, but tumors regrew after the drug treatment was withdrawn.

Conclusions: We generated homogeneous NIS/GFP co-expressing TSC2-deficient, patient-derived cells that can proliferate and migrate in vivo after intratracheal instillation. Although the animal model we describe has some limitations, we demonstrate that systemic tumors formed from TSC2-deficient cells can be monitored and quantified noninvasively over time using SPECT/CT, thus providing a much needed model system for in vivo drug testing and mechanistic studies of TSC2-deficient cells and their related clinical syndromes.

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Quantitation of LAM/TSC tumor response to drug treatment.A. Typical SPECT/CT images of mice treated with rapamycin or vehicle for 4 weeks (i.e., 6 weeks after intratracheal administration of 621-327 cells). T  =  thyroid; S  =  stomach; B  =  bladder. Arrows indicate tumors. Scale bars = 1 cm. B. 99mTc-pertechnetate uptake in LAM/TSC tumors before, during, and after treatment with rapamycin or vehicle control. 621-327 cells were administered intratracheally at time = 0. Rapamycin treatment was during weeks 2 to 6. Mice were followed an additional 2 weeks off drug.
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pone-0038589-g006: Quantitation of LAM/TSC tumor response to drug treatment.A. Typical SPECT/CT images of mice treated with rapamycin or vehicle for 4 weeks (i.e., 6 weeks after intratracheal administration of 621-327 cells). T  =  thyroid; S  =  stomach; B  =  bladder. Arrows indicate tumors. Scale bars = 1 cm. B. 99mTc-pertechnetate uptake in LAM/TSC tumors before, during, and after treatment with rapamycin or vehicle control. 621-327 cells were administered intratracheally at time = 0. Rapamycin treatment was during weeks 2 to 6. Mice were followed an additional 2 weeks off drug.

Mentions: We next investigated whether this orthotopic model would prove useful in quantifying tumor response to drug treatment. We confirmed that rapamycin does not affect 99mTcO4- uptake by NIS (Figure S5A and B). Two weeks postimplantation, tumor-bearing mice with a similar baseline of tumor burden and tumor size were treated daily for 4 weeks with intraperitoneal injection of either 8-mg/kg rapamycin or phosphate buffered saline (n = 4 mice per group). Tumor size and location were quantified by SPECT/CT every other week. As shown in Figure 6A and B, mice treated with rapamycin for at least 4 weeks exhibited a statistically significant decrease in tumor uptake of radiotracer, which rebounded to pretreatment levels 2 weeks after drug treatment was stopped. Mice sacrificed at the end of this experiment showed no significant difference in apoptosis (Figure S6A) or proliferation (Figure S6B) between rapamycin treated and untreated tumors, confirming the stability of the tumor mass after treatment ended.


Real-time monitoring of tumorigenesis, dissemination, & drug response in a preclinical model of lymphangioleiomyomatosis/tuberous sclerosis complex.

Liu F, Lunsford EP, Tong J, Ashitate Y, Gibbs SL, Yu J, Choi HS, Henske EP, Frangioni JV - PLoS ONE (2012)

Quantitation of LAM/TSC tumor response to drug treatment.A. Typical SPECT/CT images of mice treated with rapamycin or vehicle for 4 weeks (i.e., 6 weeks after intratracheal administration of 621-327 cells). T  =  thyroid; S  =  stomach; B  =  bladder. Arrows indicate tumors. Scale bars = 1 cm. B. 99mTc-pertechnetate uptake in LAM/TSC tumors before, during, and after treatment with rapamycin or vehicle control. 621-327 cells were administered intratracheally at time = 0. Rapamycin treatment was during weeks 2 to 6. Mice were followed an additional 2 weeks off drug.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3376142&req=5

pone-0038589-g006: Quantitation of LAM/TSC tumor response to drug treatment.A. Typical SPECT/CT images of mice treated with rapamycin or vehicle for 4 weeks (i.e., 6 weeks after intratracheal administration of 621-327 cells). T  =  thyroid; S  =  stomach; B  =  bladder. Arrows indicate tumors. Scale bars = 1 cm. B. 99mTc-pertechnetate uptake in LAM/TSC tumors before, during, and after treatment with rapamycin or vehicle control. 621-327 cells were administered intratracheally at time = 0. Rapamycin treatment was during weeks 2 to 6. Mice were followed an additional 2 weeks off drug.
Mentions: We next investigated whether this orthotopic model would prove useful in quantifying tumor response to drug treatment. We confirmed that rapamycin does not affect 99mTcO4- uptake by NIS (Figure S5A and B). Two weeks postimplantation, tumor-bearing mice with a similar baseline of tumor burden and tumor size were treated daily for 4 weeks with intraperitoneal injection of either 8-mg/kg rapamycin or phosphate buffered saline (n = 4 mice per group). Tumor size and location were quantified by SPECT/CT every other week. As shown in Figure 6A and B, mice treated with rapamycin for at least 4 weeks exhibited a statistically significant decrease in tumor uptake of radiotracer, which rebounded to pretreatment levels 2 weeks after drug treatment was stopped. Mice sacrificed at the end of this experiment showed no significant difference in apoptosis (Figure S6A) or proliferation (Figure S6B) between rapamycin treated and untreated tumors, confirming the stability of the tumor mass after treatment ended.

Bottom Line: Surprisingly, TSC2-deficient cells administered intratracheally resulted in rapid dissemination to lymph node basins throughout the body, and histopathological changes in the lung consistent with LAM.Estrogen was found to be permissive for tumor growth and dissemination.We generated homogeneous NIS/GFP co-expressing TSC2-deficient, patient-derived cells that can proliferate and migrate in vivo after intratracheal instillation.

View Article: PubMed Central - PubMed

Affiliation: Division of Hematology/Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America.

ABSTRACT

Background: TSC2-deficient cells can proliferate in the lungs, kidneys, and other organs causing devastating progressive multisystem disorders such as lymphangioleiomyomatosis (LAM) and tuberous sclerosis complex (TSC). Preclinical models utilizing LAM patient-derived cells have been difficult to establish. We developed a novel animal model system to study the molecular mechanisms of TSC/LAM pathogenesis and tumorigenesis and provide a platform for drug testing.

Methods and findings: TSC2-deficient human cells, derived from the angiomyolipoma of a LAM patient, were engineered to co-express both sodium-iodide symporter (NIS) and green fluorescent protein (GFP). Cells were inoculated intraparenchymally, intravenously, or intratracheally into athymic NCr nu/nu mice and cells were tracked and quantified using single photon emission computed tomography (SPECT) and computed tomography (CT). Surprisingly, TSC2-deficient cells administered intratracheally resulted in rapid dissemination to lymph node basins throughout the body, and histopathological changes in the lung consistent with LAM. Estrogen was found to be permissive for tumor growth and dissemination. Rapamycin inhibited tumor growth, but tumors regrew after the drug treatment was withdrawn.

Conclusions: We generated homogeneous NIS/GFP co-expressing TSC2-deficient, patient-derived cells that can proliferate and migrate in vivo after intratracheal instillation. Although the animal model we describe has some limitations, we demonstrate that systemic tumors formed from TSC2-deficient cells can be monitored and quantified noninvasively over time using SPECT/CT, thus providing a much needed model system for in vivo drug testing and mechanistic studies of TSC2-deficient cells and their related clinical syndromes.

Show MeSH
Related in: MedlinePlus