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


RESULTS
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 Rapamycin inhibited tumor growth, but tumors regrew after the drug treatment was withdrawn.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.
Division of Hematology/Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America.
Fangbing
F
Liu
Elaine P
EP
Lunsford
Jingli
J
Tong
Yoshitomo
Y
Ashitate
Summer L
SL
Gibbs
Jane
J
Yu
Hak Soo
HS
Choi
Elizabeth P
EP
Henske
John V
JV
Frangioni
D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D015153:Blotting, Western; D002471:Cell Transformation, Neoplastic; D004195:Disease Models, Animal; D049452:Green Fluorescent Proteins / Q000235:genetics; D006801:Humans; D018192:Lymphangioleiomyomatosis / Q000188:drug therapy* / Q000473:pathology; D051379:Mice; D008819:Mice, Nude; D008856:Microscopy, Fluorescence; D008991:Monitoring, Physiologic / Q000379:methods*; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed; D014402:Tuberous Sclerosis / Q000188:drug therapy* / Q000473:pathology; D000077005:Tuberous Sclerosis Complex 2 Protein; D014407:Tumor Cells, Cultured; D025521:Tumor Suppressor Proteins / Q000235:genetics
D000970:Antineoplastic Agents; C000624653:TSC2 protein, human; C000624654:Tsc2 protein, mouse; D000077005:Tuberous Sclerosis Complex 2 Protein; D025521:Tumor Suppressor Proteins; D049452:Green Fluorescent Proteins