The Fight against Cancer by Microgravity: The Multicellular Spheroid as a Metastasis Model

Abstract

Cancer is a disease exhibiting uncontrollable cell growth and spreading to other parts of the organism. It is a heavy, worldwide burden for mankind with high morbidity and mortality. Therefore, groundbreaking research and innovations are necessary. Research in space under microgravity (µg) conditions is a novel approach with the potential to fight cancer and develop future cancer therapies. Space travel is accompanied by adverse effects on our health, and there is a need to counteract these health problems. On the cellular level, studies have shown that real (r-) and simulated (s-) µg impact survival, apoptosis, proliferation, migration, and adhesion as well as the cytoskeleton, the extracellular matrix, focal adhesion, and growth factors in cancer cells. Moreover, the µg-environment induces in vitro 3D tumor models (multicellular spheroids and organoids) with a high potential for preclinical drug targeting, cancer drug development, and studying the processes of cancer progression and metastasis on a molecular level. This review focuses on the effects of r- and s-µg on different types of cells deriving from thyroid, breast, lung, skin, and prostate cancer, as well as tumors of the gastrointestinal tract. In addition, we summarize the current knowledge of the impact of µg on cancerous stem cells. The information demonstrates that µg has become an important new technology for increasing current knowledge of cancer biology.

RCCS Bioreactor-Based Modeled Microgravity Affects Gastric Cancer Cells and Improves the Chemotherapeutic Effect

“…Significant changes in cell membranes, reorganization of the cytoskeleton, limited proliferation, and changes in protein and gene expression were observed [ 9 , 21 ]. Recent studies indicate that altered gravity induces shear stresses at the membrane surface, one of the essential factors in sensitizing cancer cells [ 22 ]. Additionally, our previous study showed morphological changes in cancer cells exposed to MG, i.e., stress fibers, membrane blebbing, and cytoskeleton reorganization [ 23 ].…”

Impairment of 7F2 osteoblast function by simulated partial gravity in a Random Positioning Machine

“…The similarities between our results and those of others using clinostats as earth-based analogs for simulating microgravity and partial-gravity conditions and results observed in space-flown sample in real microgravity, suggest that many of the reported effects might primarily be due to alterations in the modeled reduced gravity conditions. However, for the sake of scientific rigor, and as the mechanisms of gravisensing in SMG or SPG are as yet unclear 44 we would like to acknowledge the possibility that some of the phenomena observed in clinostats and the RPM could also be (in part) due to indirect effects in the environment (e.g., changes in fluid shear or mass transfer) 44 – 47 . Moreover, while differences in vibration, fluid shear, or mass transfer may occur between different path files in the RPM SW , these have yet to be quantified or identified as significant 25 , 31 .…”

Extraterrestrial Gynecology: Could Spaceflight Increase the Risk of Developing Cancer in Female Astronauts? An Updated Review

“…Microgravity has different effects on normal and cancer cells, but the related underlying mechanisms are still being elucidated. Experiments using normal or cancer cells performed in space on the International Space Station (ISS) or under s-µg-conditions using devices approved by ESA and NASA to create µg conditions on Earth (known as groundbased facilities) [131], belong to a newly evolving area of research in oncobiology [132]. Numerous studies have demonstrated how a short-and long-term exposure to r-and s-µg influences differentiation, proliferation, migration, survival, apoptosis, adhesion, and other processes involved in carcinogenesis [53].…”