Molecular Pathway Linking Colon Cancer To A High Fat Diet (And Obesity)

By Attributed to Charles Mellin - WgF1LrUvFdNysA at Google Cultural Institute, zoom level maximum, Public Domain, https://commons.wikimedia.org/w/index.php?curid=13334241

A study has shown a molecular pathway linking obesity and a high fat diet to colon cancer.  Excerpts from the article (italics) with some of my own comments inserted:

Scientists in the U.S. have identified a molecular pathway that appears to play a key role in the link between a high-fat diet (HFD) and the development of colorectal cancer. The research, led by the Cleveland Clinic’s Sheerlarani Karunanithi, and Matthew Kalady, suggests that it may one day be possible to develop drugs that reduce tumor growth associated with obesity and a diet that is high in fat. 

Or people can lose weight and eat lower-fat diets.  What's wrong with that approach?

Their research is published today, in Stem Cell Reports, in a paper titled, “RBP4-STRA6 Pathway Drives Cancer Stem Cell Maintenance and Mediates High-Fat Diet-Induced Colon Carcinogenesis.”

The Cleveland Clinic team’s review of published research indicated that high expression levels of two vitamin A signalling proteins—serum retinol binding protein (RPB4), stimulated by retinoic acid 6 (STRA6)—in colorectal cancer tumors is associated with poor prognosis, increased tumor metastasis and recurrence, and resistance to cancer therapy. The RBP4-STRA6 pathway triggers the JAK2-STAT3 signaling cascade…

That is useful information - perhaps the greatest utility is motivation to lose wright and change diets, as there is now more concrete evidence linking unhealthy eating habits and an unhealthy weight to colon cancer.

...Our data clearly indicate that RBP4-STRA6 pathway is necessary for the optimal expression of stem cell markers such as NANOG, SOX2, and LGR5, and thereby for maintaining the colon CSC pool,” the authors conclude in their published paper. "We have known the influence of diet on colorectal cancer,” commented Matthew Kalady, M.D., colorectal surgeon, and co-director of the Cleveland Clinic Comprehensive Colorectal Cancer Program. “However, these new findings are the first to show the connection between high-fat intake and colon cancer via a specific molecular pathway. We can now build upon this knowledge to develop new treatments aimed at blocking this pathway and reducing the negative impact of a high-fat diet on colon cancer risk."

One could reasonably reduce the risk of a high-fat diet by no longer eating the high-fat diet.

“The interesting finding here is that the high fat diet-induced effects appear to also involve the stem cell program, which is interesting for tumor growth and has implications on therapies, as tumor stem cells are also therapeutically resistant...” 

It would seem therefore if high-fat diets maintain colon cancer stem cells - cells that can "fuel" the tumor and which may be more resistant to therapy - then one can ask: should colon cancer patients be given nutritional programs that take this into account?

There's nothing wrong with developing new therapies, but those therapies should be in addition to healthy eating, not a substitute for it.