Common Effects on Cancer Cells Exerted by a Random Positioning Machine and a 2D Clinostat

PLoS One. 2015 Aug 14;10(8):e0135157. doi: 10.1371/journal.pone.0135157. eCollection 2015.

Abstract

In this study we focused on gravity-sensitive proteins of two human thyroid cancer cell lines (ML-1; RO82-W-1), which were exposed to a 2D clinostat (CLINO), a random positioning machine (RPM) and to normal 1g-conditions. After a three (3d)- or seven-day-culture (7d) on the two devices, we found both cell types growing three-dimensionally within multicellular spheroids (MCS) and also cells remaining adherent (AD) to the culture flask, while 1g-control cultures only formed adherent monolayers, unless the bottom of the culture dish was covered by agarose. In this case, the cytokines IL-6 and IL-8 facilitated the formation of MCS in both cell lines using the liquid-overlay technique at 1g. ML-1 cells grown on the RPM or the CLINO released amounts of IL-6 and MCP-1 into the supernatant, which were significantly elevated as compared to 1g-controls. Release of IL-4, IL-7, IL-8, IL-17, eotaxin-1 and VEGF increased time-dependently, but was not significantly influenced by the gravity conditions. After 3d on the RPM or the CLINO, an accumulation of F-actin around the cellular membrane was detectable in AD cells of both cell lines. IL-6 and IL-8 stimulation of ML-1 cells for 3d and 7d influenced the protein contents of ß1-integrin, talin-1, Ki-67, and beta-actin dose-dependently in adherent cells. The ß1-integrin content was significantly decreased in AD and MCS samples compared with 1g, while talin-1 was higher expressed in MCS than AD populations. The proliferation marker Ki-67 was elevated in AD samples compared with 1g and MCS samples. The ß-actin content of R082-W-1 cells remained unchanged. ML-1 cells exhibited no change in ß-actin in RPM cultures, but a reduction in CLINO samples. Thus, we concluded that simulated microgravity influences the release of cytokines in follicular thyroid cancer cells, and the production of ß1-integrin and talin-1 and predicts an identical effect under real microgravity conditions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Culture Techniques / instrumentation*
  • Cell Culture Techniques / methods*
  • Cell Line, Tumor
  • Cytokines / biosynthesis*
  • Humans
  • Neoplasm Proteins / biosynthesis*
  • Spheroids, Cellular / metabolism*
  • Weightlessness

Substances

  • Cytokines
  • Neoplasm Proteins

Grants and funding

The authors would like to thank the German Space Agency (DLR; (DG) BMWi projects 50WB1124 and 50WB1524), the European Space Agency (ESA; ESA-CORA-GBF-2011-005 project Device Comparison; ESA-CORA-GBF- 2013-001 project THYROID 3) (DG), Aarhus University, Denmark (DG), the University of Regensburg (JG), and DGLRM (Young Fellow Program for EW and GA). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.