How are stress and cancer growth interlinked? Why is stress management important for cancer patients? This blog will discuss all the relations between the Brain, gut, and Tumour.
There is new research which shows stress directly affects cancer growth. Evidence shows increased growth of the tumour in mice.
The Hidden Link Between Stress and Cancer
We all know that stress isn’t good for our health — it can make us feel anxious, mess with our sleep, and even upset our stomach. But here’s something you may not know: stress can also help cancer grow.
Recent studies have found that the brain, the gut, and tumours are connected in a way scientists never fully understood before. When we’re under stress, our brain sends signals to our gut, and these signals can actually create a friendlier environment for tumours to grow, especially in colorectal cancer.
The Science Made Simple
How the Brain–Gut Circuit Works
a) Brain to Gut (Top-Down Signals)
- The brain sends signals to the gut through the autonomic nervous system — mainly the vagus nerve and other spinal nerves.
- These signals control:
- Movement of the intestines
- Secretion of digestive juices
- Immune cell activity in the gut
Example:
When you’re stressed, your brain signals the gut to slow digestion — that’s why you may feel stomach cramps or nausea during anxiety.
b) Gut to Brain (Bottom-Up Signals)
- The gut sends signals back to the brain using:
- Neural pathways (like the vagus nerve)
- Hormones (like serotonin, which is mostly made in the gut)
- Immune signals (like cytokines)
Example:
When your gut is upset (like during an infection), it can make you feel fatigued or anxious — that’s your gut signalling distress to the brain.
How the Brain-gut-tumour circuit works
In the colorectal cancer study, this circuit works in a more specific way:
- Step 1: The lateral septum in the brain (linked to emotions and stress) activates GABA-producing neurons.
- Step 2: These neurons send a chain of signals (a polysynaptic pathway) to enteric cholinergic neurons in the gut.
- Step 3: These gut neurons extend nerve fibres into the tumour microenvironment.
- Step 4: The gut neurons release GABA around the tumour.
- Step 5: Cancer cells, equipped with special GABA receptors, “use” this signal to grow faster.
Stress Turns Up the Volume
Stress is a normal part of life, but when it becomes chronic — lasting for weeks or months — it can start to affect your body in ways you can’t see.
In recent experiments with mice, scientists discovered something surprising: when the mice were kept under continuous stress, the tumours in their bodies grew faster and became more aggressive. Why? Stress signals from the brain triggered a special pathway to the gut, releasing chemicals that the cancer cells used as fuel for growth.
In the real world, this means that long-term stress — whether from work pressure, emotional struggles, or chronic anxiety — could make it easier for certain cancers, like colorectal cancer, to grow and spread more quickly.
This research is a reminder that managing stress isn’t just about mental health — it could play a powerful role in protecting your physical health, too.
Evidence in Humans
A recent publication in PubMed shows that in patients with colorectal cancer, those with higher brain activity in the septal region had larger tumours.
PubMed article Colorectal cancer cells hijack a brain-gut polysynaptic circuit from the lateral septum to enteric neurons to sustain tumor growth.
Why This Discovery Matters
This research is more than just a scientific breakthrough — it’s a wake-up call. By understanding the brain–gut–tumor pathway, doctors and researchers can take important steps to improve cancer care:
- Smarter Treatments: Knowing that stress signals can “feed” tumours means scientists could design new therapies that block these brain-to-gut messages, slowing tumour growth.
- Personalised Care: Brain scans and stress markers could one day help doctors predict how aggressive a tumour might become, leading to more tailored treatment plans.
- Stress Management as Medicine: Techniques like meditation, yoga, breathing exercises, and counselling might not just improve quality of life — they could also help in slowing cancer progression when combined with standard medical treatments.
This discovery highlights a simple truth: caring for your mental health is just as important as treating a physical disease
“Your mental well-being isn’t just about feeling good — it could play a real role in your physical health, including how your body fights diseases like cancer. By managing stress, we might just be helping the body fight smarter.”.
Refrence