Microgravity, Stem Cells, and Cancer: A New Hope for Cancer Treatment

Abstract

Humans are integrated with the environment where they live. Gravitational force plays an important role in shaping the universe, lives, and even cellular biological processes. Research in the last 40 years has shown how exposure to microgravity changes biological processes. Microgravity has been shown to have significant effects on cellular proliferation, invasion, apoptosis, migration, and gene expression, specifically in tumor cells, and these effects may also exist in stem and cancer stem cells. It has also been shown that microgravity changes the effects of chemotherapeutic drugs. Although studies have been carried out in a simulated microgravity environment in cell culture lines, there are few animal experiments or true microgravity studies. Cancer remains one of the most significant problems worldwide. Despite advances in medical science, no definitive strategies have been found for the prevention of cancer formation or to inform treatment. Thus, the microgravity environment is a potential new therapeutic strategy for future cancer treatment. This review will focus on current knowledge on the impact of the microgravity environment on cancer cells, stem cells, and the biological behavior of cancer stem cells.

The CellBox-2 Mission to the International Space Station: Thyroid Cancer Cells in Space

“…This observation had been reported earlier during the Shenzhou-8/SimBox spaceflight experiment [22,23] and in studies using microgravity-simulating devices, such as clinostats or the RPM [15,16,25]. Gravitational unloading is known to influence several processes in cancer cells: differentiation, proliferation, apoptosis, growth, migration and invasion, among others [23,26]. The gene expression of a large number of genes in various cell types in vivo and in vitro is differentially altered in space compared to 1g conditions on Earth [23,[27][28][29].…”

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

“…Since µ g delivers an exceptional environment for cell culture and has been shown to stimulate cellular changes and processes that could not be achieved under normal gravitational conditions [ 59 ], the investigation of how CSCs act under µ g is an interesting topic. Even though, to our knowledge, the number of published studies on CSCs exposed to µ g conditions is limited, researchers have initiated work in this essential field during recent years [ 59 , 60 ]. Most knowledge has been obtained from thyroid, breast, and prostate cancer cells studies.…”

The State of the Art of Piezo1 Channels in Skeletal Muscle Regeneration

“…Cell mechanical properties, including elasticity, viscoelasticity [ 70 ], and cytoskeletal organization (namely mechano-responsive structures) are the most affected cell compartments in real or simulated microgravity [ 71 ]. Microgravity disrupts the intracellular tension balance and causes irregular cytoskeleton formation, with substantial implications in the regulation of cell growth, locomotion and survival [ 72 ]. For example, extracellular matrix proteins, cytoskeletal components and intermediate filaments are significantly affected in human endothelial cells when cultured in a random positioning machine simulating microgravity conditions [ 73 ].…”