Effects of simulated microgravity on thyroid carcinoma cells.
We aimed to investigate whether simulated microgravity on thyroid carcinoma cells could help to perform in vitro cancer studies such as antitumor drug tests more reliable and to spare animal experiments. We cultured cancer cells at 0 g to enable formation of three-dimensional multicellular tumor spheroids (MCTS), which will resemble the originating tumors. Under microgravity human follicular cells (ML-1 cell line) keep floating with-out stirring so that initial cell-cell interactions required for spheroid formation will be induced by forces due to biochemical components actually expressed on surfaces of cells, whereas gravity related push- or shear events will not influence MCTS formation. Within 12 hours of clinorotation the monolayer turned spontaneously into MCTS with remarkable features: An increase of extracellular matrix proteins and TGF-beta 1. Thyroglobulin, ft3 and ft4 secretion were markedly reduced. These data are in agreement with the observation that astronauts show low thyroid hormone levels after spaceflight.
Grimm
Daniela
D
Institute of Clinical Pharmacology and Toxicology, Benjamin Franklin Medical Center, Freie Universitat, Berlin, Germany. dgrimm@zedat.fu-berlin.de
Kossmehl
Peter
P
Shakibaei
Mehdi
M
Schulze-Tanzil
Gundula
G
Pickenhahn
Holger
H
Bauer
Johann
J
Paul
Martin
M
Cogoli
Augusto
A