Microgravity Affects Thyroid Cancer Cells during the TEXUS-53 Mission Stronger than Hypergravity

• Main Authors: Sascha Kopp, Marcus Krüger, Johann Bauer, Markus Wehland, Thomas J. Corydon, Jayashree Sahana, Mohamed Zakaria Nassef, Daniela Melnik, Thomas J. Bauer, Herbert Schulz, Andreas Schütte, Burkhard Schmitz, Hergen Oltmann, Stefan Feldmann, Manfred Infanger, Daniela Grimm
• Format: Article
• Language: English
• Published: MDPI AG 2018-12-01
• Series: International Journal of Molecular Sciences
• Subjects: Microgravity; hypergravity; random positioning machine; thyroid cancer; sounding rocket; cytoskeleton; focal adhesion; extracellular matrix
• Online Access: https://www.mdpi.com/1422-0067/19/12/4001

Thyroid cancer is the most abundant tumor of the endocrine organs. Poorly differentiated thyroid cancer is still difficult to treat. Human cells exposed to long-term real (r-) and simulated (s-) microgravity (&#181;<i>g</i>) revealed morphological alterations and changes in the expression profile of genes involved in several biological processes. The objective of this study was to examine the effects of short-term &#181;<i>g</i> on poorly differentiated follicular thyroid cancer cells (FTC-133 cell line) resulting from 6 min of exposure to &#181;<i>g</i> on a sounding rocket flight. As sounding rocket flights consist of several flight phases with different acceleration forces, rigorous control experiments are mandatory. Hypergravity (hyper-<i>g</i>) experiments were performed at 18<i>g</i> on a centrifuge in simulation of the rocket launch and s-&#181;<i>g</i> was simulated by a random positioning machine (RPM). qPCR analyses of selected genes revealed no remarkable expression changes in controls as well as in hyper-<i>g</i> samples taken at the end of the first minute of launch. Using a centrifuge initiating 18<i>g</i> for 1 min, however, presented moderate gene expression changes, which were significant for <i>COL1A1</i>, <i>VCL</i>, <i>CFL1</i>, <i>PTK2</i>, <i>IL6,</i> <i>CXCL8</i> and <i>MMP14</i>. We also identified a network of mutual interactions of the investigated genes and proteins by employing <i>in-silico</i> analyses. Lastly, &#181;<i>g</i>-samples indicated that microgravity is a stronger regulator of gene expression than hyper-<i>g</i>.