Researching Cancer in Space
- 1st Nov 2024
- Author: Emma Mosley
Cancer is a diagnosis no one ever wants to hear.
Of people born in the UK in 1961, nearly one in two will develop cancer during their lifetime. Cancer rates are predicted to rise by 2% to reach 506,000 new cases a year in the UK between now and 2040. However, you will be relieved to know that cancer survival rates have doubled in the last 50 years. Meaning that 50% of those diagnosed today will survive for ten years or more.
With cancer affecting us here on Earth, why are space agencies like NASA and ESA researching cancer in space?
Space is hard...
Getting humans into space is a huge feat of engineering with spaceflight taking a toll on the human body. This can make astronauts feel temporarily unwell and can even leave lasting effects on the body.
There is also the danger of radiation from deep space and the Sun. The Earth’s magnetic field and atmosphere help protect us from this here on the ground, including Ultraviolet (UV) rays from the Sun, particularly UV-B rays, which can cause severe burns on our skin if we are exposed to them. The Ozone Layer in the Earth’s atmosphere blocks about 95% of UV-B rays, though we all still need sun cream to protect ourselves.
There are plans to send astronauts back to the Moon as part of NASA's Artemis missions. This will take them beyond low Earth orbit and expose them to radiation from deep space, the Van Allen belt, and the Sun. To protect their astronauts, NASA is researching the effects of radiation on the human body.
Any astronaut that leaves the safety of our atmosphere is exposed to radiation. For astronauts that spend six months onboard the International Space Station (ISS), they receive 50 – 100 millisieverts of radiation. This is equivalent to 2,500 – 5,000 chest X-Rays!
Why is radiation dangerous?
Radiation comes in two flavours: non-ionising which tends not to be harmful, and ionising which is very harmful.
Ionising radiation is energy given out that is strong enough to knock electrons off atoms, or "ionising" them. It can be given out from radioactive sources and certain reactions, like the ones found within the Sun. This energy is in two forms:
- Subatomic particles - like neutrons, alpha particles (two protons and two neutrons) and beta particles (electrons and positrons)
- Electromagnetic waves - from UV rays onwards on the Electromagnetic spectrum
These travel at close to the speed of light, except for alpha particles as they are heavier than the others.
DNA is the code of instructions our cells follow for us to exist and function. Radiation can damage the DNA within our cells by ionising sections or even breaking it up. When there is enough changes for the cell to become abnormal, it can start to multiply uncontrollably. This is cancer and it can spread throughout the body. The more damage DNA receives, the bigger the chance of our cells becoming cancerous.
Understanding how cancerous cells behave and how they interact with medicines can help doctors to treat cancer effectively. This makes Cancer Research a very important research topic globally, with labs across the world working on studies looking for breakthroughs in treatment.
Sometimes though, there are some problems in trying to get to an answer. Gravity can get in the way and unfortunately, we cannot escape the effects of gravity here on the surface of Earth. So how do the scientists get round the effects of gravity? Well they just send their experiments into space instead!
What's different in Space?
The International Space Station (ISS) is in orbit around Earth at roughly 400km above the surface. This is where astronauts spend most of their time when in space and the conditions are very different from those on Earth.
The ISS is orbiting around Earth at just the right speed as Gravity is pulling it down, it keeps missing the ground so it keeps going around the Earth. Being in constant freefall makes the astronauts and objects appear weightless and floating around, we call this environment Microgravity.
This environment is perfect to conduct experiments with the limitations caused by gravity here on Earth out of the picture. The ISS can be described as a floating laboratory offering the unique conditions of Microgravity to scientists across the globe. So far, the ISS has conducted over 3,000 experiments onboard. These experiments can range from trying to understand the universe, Earth observation to complex biology looking at plants and animals. It would come as no surprise that cancer research has been undertaken onboard the ISS.
What breakthroughs have we found so far?
There are many advantages to using the microgravity environment. Here are a few of the breakthroughs that have been found so far:
Growing Human Cells
In 1960, Henrietta Lack's cancer cells (HeLa) became the first human cells in space. They were sent up before Yuri Gagarin, the first person in space, to see how human cells would cope with the space environment. Since then there have been countless experiments with HeLa and other cell cultures, looking at how they grow and develop.
Through these experiments, scientists have found that cells tend to age quicker in space due to the stress of being in a microgravity environment. They also grow three times quicker than on Earth, which is a positive for scientists as it reduces the time needed for experiments.
Forming tumours
When researching the behaviour of cancer cells, scientists grow them in a lab. These cells tend to be placed in a petri dish which gives a flat two-dimensional shape, or in a liquid suspension which creates layers due to gravity. Trying to form cancer cells as a three-dimensional growth, like we would find in the human body, is very difficult here on Earth.
By growing them in space, however, these cancer cells start to form a three-dimensional shape instead of a two-dimensional petri dish blob. The cells start to behave as if they are inside the human body, forming into a growth or a tumour. Over the years, cancer cells have been sent into space to be grown and then brought back to Earth to be studied. The structure of the cancer tumour, how it grows, and interacts with drugs can be studied in greater detail.
Trying to recreate the same cancer tumour structures on the ground was extremely difficult until NASA developed the Bioreactor. This neat piece of kit rotates the samples at just the right speed so that there are no forces exerted on the cells. It is as if they are in free fall or floating like in space. Rotating the cells so they don't collide with the wall of the reactor stops them from getting damaged, which would limit their growth. These bioreactors are used today across research and industry, including creating samples for cancer research.
Protein Crystal growth
Proteins are used in our cells for a range of vital jobs but in cancer cells these can form incorrectly. To find out more about these proteins, we can grow them into crystals to peer inside and determine their structure. By looking at the structure of protein crystals we can see more about how these proteins are formed, interact and work within cells. The only issue is growing the perfect protein crystals here on Earth.
Growing these crystals on Earth is tricky, as gravity affects the way the liquid protein starts to crystallise. Sedimentation, convection currents, and temperature affect the overall growth of the crystals. When grown in the lab, they are small and have varying purities making it difficult to analyse. By using microgravity to control these effects, the crystals grow much bigger and purer, making them easier to analyse. Protein crystals have been grown in space since the mid 1980s on the Space Shuttles and Space Station Mir. Up to 2021, there were 500 different protein crystal growth experiments on the ISS alone.
New discoveries on the Horizon
Through research conducted in space, there has been new discoveries in our understanding and treatments for cancer. This work is not slowing down either.
Through looking at protein crystal growth onboard the ISS, more information has been gained in how to administer the immunotherapy drug Pembrolizumab effectively. Clinical trials are currently underway to look at patients having an injection rather than a half hour infusion in hospital.
President Joe Biden and his wife Jill Biden reignited the Cancer Moonshot initiative which was started by President Barack Obama in 2016. The aim of this initiative in the US is to cut deaths by cancer in half in the next 25 years and to improve the experience of people touched by cancer. Part of this initiative is for government departments to join in and this includes NASA. NASA will be working with doctors and researchers with their Human Research Program, who are looking at making human space travel safer. They will be researching all aspects of cancer from causes to treatments through conducting many experiments in space and building on the research already undertaken by NASA over the years.
The demand for conducting research in the microgravity environment, is higher than ever. Companies conducting research like cancer treatment drugs, want to use microgravity to get more detailed results of their drug. This helps to reduce the failure of new drugs at later stages, like clinical trials. One estimate claims that just a 10% improvement in failure prediction rates before conducting clinical trials could save $100 million in development costs.
There is momentum building towards further research and manufacturing in space from the private sector. Private companies are coming together to design and build their own space stations in low Earth orbit. There they can provide companies an opportunity to conduct experiments and manufacture items commercially onboard.
There are many in development including Blue Origin's Orbital Reef and Axiom Space's Axiom Station. It is possible in the future that drugs, like a protein based immunotherapy or even human organs could be manufactured onboard a space station. Then used to treat people on the ground. A truly futuristic concept that could become reality!
While cancer seems scary, the future is looking bright with more research being done than ever by space agencies and private companies across the globe.
The next time anyone wonders, what's the point in sending people into space? It's to save lives!
Image Credits:
Banner - ISS with the backdrop of space and the thin blue line of Earth’s atmosphere – NASA
Image 1a - Electromagnetic Spectrum – NASA
Image 1b - An illustration of a DNA strand being damaged by ionising radiation. - Dr. Frank Cucinotta, NASA/Johnson Space Center, Prem Saganti, Lockheed Martin
Image 2 - British astronaut Tim Peake, exercising using the MARES equipment onboard the ISS. – NASA
Image 3a - The NASA Bioreactor developed to grow large three-dimension cell clusters. - NASA
Image 3b - ESA astronaut Alex Gerst with the Crystallisation of RAS in Space (CASIS PCG 17) investigation. – NASA
Image 4a - NASA astronaut Frank Rubio talking during a Cancer Moonshot event with NASA and the Department of Health and Human Services. - NASA/Keegan Barber
Image 4b - Two people wearing lab coats with the Thales Alenia Space logo guide stand on moveable staircases while working on assembling components of Axiom Station's Hab One (Ax-H1) - Axiom Space CC BY-NC-SA 4.0
