Glucose and Glutamine: Cancer’s primary “fuels.”

Let’s start with what we know about the role of glucose in cancer.

• Cancer cells are greedy, sucking up more glucose than normal cells.

• Glucose is then fermented in the cytoplasm of the cell, producing a bit of energy while also sythesizing building blocks needed to make new cancer cells.

• When glucose is in short supply, this “biomass synthesis” is slowed.

• Normal cells adapt: they switch to other fuels:

  • Muscle and heart prefers fats for energy

  • The brain can’t use fats but evolution created a solution: Ketones!

• Tumor cells sufferfrom this metabolic switch because they are not as fuel flexible as normal cells.

The glucose/insulin connection…

1.     dietary carbohydrates spike blood sugar levels which in turn causes a spike in insulin secretion

2.     insulin moves glucose from the blood into cells to be used for energy. 

3.   cancer cells have more glucose transporters and insulin receptors than normal cells

4.     insulin acts as an anabolic hormone, signaling “grow! grow! grow!” to cancer cells

What about glutamine, cancer’s other primary promoter?

• Glutamine is a “conditionally essential” amino acid that is critical to the health of our immune system and the growth and repair of tissues, incliding muscle mass.

• Given its importance, our bodies have developed a network of systems to ensure a smooth and steady supply.

• Cancer cells hijack these activities to ensure a steady supply of glutamine.

• Cancer cells then ferment this glutamine in the mitochondria, providing the needed building blocks for cancer cell growth and progression.

How do cancer cells get the glutamine they need?

1. diet

2. recycling

3. making new glutamine from other amino acids

4. extracting it from the microenvironment of the cancer cell

5. stealing it from neighboring cells

How can we put the brakes on glutamine?

• Careful to not be too restrictive here…it’s important to get enough but not too much so keep to a well-formulated plan that divides your protein between meals, a switch from most people’s preference for loading most of the protein in the evening meal.

• “Forks down” at least 3 hours before bedtime is also important in limiting overnight access.

• You have probably found YouTube videos from Dr. Seyfried saying that we need to shut down glutamine with drugs such as DON - but what is often lost in viewing these is that we don’t yet have medically supervised access to the most potent blockers.

And what about other amino acids, such as methionine?

• Methionine is an “essential” amino acid, meaning that you do need to get it through dietary intake.

• It’s involved in growth and repair of tissue along with other crucial roles including methylation and detoxification.

• Some cancers hijack this pathway; although there is no universal test for determining which cancers favor methionine, there is a blood testing protocol and some gene SNPs that can help to sort this out.

• With short-term restriction (overnight fasting; short modified fasts) cells recycle their limited resources, just enough to keep essential activites running while choking down the supply to cancer cells.

• Ssafety first! Compromising those pathways also compromises methylation and detoxification so it’s best to work with an integrative practitioner who knows how to test, assess and treat.