3 min|Dr. Alex Chan

Stress & the Cancer Conundrum


Today Dr. Alex Chan contributes to our blog with a post about the role of stress in the development of cancer. Dr. Alex Chan completed a two year residency at Integrative before joining the clinic in full time private practice and as the Residency Program Coordinator. Dr. Alex Chan has a special interest in integrative cancer care and has devoted herself to additional training in the field of oncology. She applies this extensive knowledge to treating patients within our Cancer Program.

Our peripheral nervous system is organized into two branches:

1) The somatic nervous system that controls all voluntary action like movement of muscles and joints 2) The autonomic nervous system that is responsible for involuntary responses like breathing, heart rate and stress.

The autonomic nervous system is further divided into the sympathetic and parasympathic nervous systems. These two systems have complementary but opposite functions. The sympathetic is the well-known 'fight and flight' system, while the parasympathetic is all about restoration and relaxation. Both of these systems are essential as the sympathetic ramps us up into action and the parasympathetic calms us down. Our bodies are always working to maintain this equilibrium.

As long as we remain in this homeostasis we are protected from stressors becoming out of control and tipping us into an imbalanced state. Our bodies interpret anything that draws us out of homeostasis as a stressor whether it is mentally, physically or emotionally triggered. This stress manifests physiologically with changes in our anatomic, biochemical, neurological, electric and genetic responses.

Initially there is increased arousal to a stressor, also known as an allostatic response.

When we successfully address this stressor, our brain switches off the allostatic response to reduce burden on the body. However, for some situations, the stressor is not successfully addressed and this allostatic response continues. In this case, the demand being placed on the body never alleviates and the constant barrage of stress responses increases the development of disease. In a chronic state of stress, biochemical factors like cortisol, norepinephrine and epinephrine are constantly being produced. This production up-regulates the genes involved in this process.

While each of these products is essential in small amounts, in large amounts they have many effects like decreasing blood flow to the digestive tract, increasing the amount of free glucose in the bloodstream, and modifying gene expression of transcription factors that control healthy growth, immunity and metabolism. Here we see that uncontrolled stress creates a domino effect and genetic chaos by up and down-regulating the wrong genes. Altering this gene expression causes abnormal cell states, irregular cell proliferation and dysfunction of healthy controls.

Cancer is a complex process

It involves the interactions between the innate biology (genotype) and environmental stressors. In our internal milieu, these stressors modify the ways that the genes turn on and off (epigenetics). These changes can cause enough of a shift for cancer to develop as an outward expression (phenotype). The stress response also triggers inflammation which is the breeding ground for cellular damage and cancerous changes.

Cancer is a disease effecting every single system, organ, cell pathway, and gene in the body. Luckily the stress response can be modulated through activities like meditation, breathing and exercise. Both during prevention, and active cancer therapy, restoring autonomic balance should be an integral part of our lifestyle.