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

Int J Mol Sci. 2018 Dec 12;19(12):4001. doi: 10.3390/ijms19124001.

Abstract

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 (µg) 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 µg on poorly differentiated follicular thyroid cancer cells (FTC-133 cell line) resulting from 6 min of exposure to µg 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-g) experiments were performed at 18g on a centrifuge in simulation of the rocket launch and s-µg 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-g samples taken at the end of the first minute of launch. Using a centrifuge initiating 18g for 1 min, however, presented moderate gene expression changes, which were significant for COL1A1, VCL, CFL1, PTK2, IL6, CXCL8 and MMP14. We also identified a network of mutual interactions of the investigated genes and proteins by employing in-silico analyses. Lastly, µg-samples indicated that microgravity is a stronger regulator of gene expression than hyper-g.

Keywords: Microgravity; cytoskeleton; extracellular matrix; focal adhesion; hypergravity; random positioning machine; sounding rocket; thyroid cancer.

MeSH terms

  • Cell Line, Tumor
  • Gene Expression Regulation, Neoplastic
  • Gene Regulatory Networks
  • Humans
  • Hypergravity*
  • Membrane Proteins / metabolism
  • Space Flight*
  • Thyroid Neoplasms / genetics
  • Thyroid Neoplasms / pathology*
  • Weightlessness*

Substances

  • Membrane Proteins