I read this paper last week.
"An Integrated tumor, immune and microbiome atlas of colon cancer",
Roelands et al., Nat Med. 2023 May 19. doi: 10.1038/s41591-023-02324-5. Online ahead of print.PMID: 37202560
https://www.nature.com/articles/s41591-023-02324-5
The journal Nature Medicine is a journal with 53 impact factor (which is ridiculously high from the standpoint of researchers. Usually 5+ IF is considered decent. 10+ is considered a leading journal for the field). That makes Nat Med one of most prestigious or highly regarded journal in medical research.
The authors are from Qatar, Netherland and Italy.
This is an original research providing a synthetic view on colon cancer.
Cancer research progressed with limitations of the time. Different types of molecular analysis became available over time. Earlier research lacked analyses that are now available.
This report integrates several data analysis methods and provides a most contemporary overview of colon cancer that was unavailable or just assumed before.
At first, the authors correctly pointed out that current cancer database most used by cancer researchers (called The Cancer Genome Atlas [TCGA]) is not "complete" and has missing data, such as clinical outcomes, immune activity, or microbiome/bacterial flora at cancer and non-cancer sites. The shortcoming is by historical reasons.
The authors collected treatment-naïve colon cancer and pairing non-cancer colon tissue samples at medical center in Netherlands from 2001-2015. They collected 384 sample sets that passed quality control, which make the cohorts they used.
They applied various molecular analyses (gene mutation, gene expression, immune cell typing, bacterial rRNA sequencing/microbiome) on the cancer and normal-looking colon tissue, and followed up on the clinical outcomes/survival data. So that we can have overview on colon cancer.
There are questions like,
"some gut bacteria are associated with colon cancer. Do they correlate with clinical outcomes/survival?"
"what kind of gene mutation or what type of colon cancer is bad with poor prognosis, or is more manageable with favorable outcome?"
"immune system is important for cancer outcomes. What kind of immune cells are critical to anti-tumor activity?" etc etc.
And these questions can be examined with their datasets.
The report was inevitably somewhat descriptive with statistics, but full of interesting findings.
On the other hand to be honest, with 6 figures, 10 extended data figures and 14 supplementary information figures, it was pain to read through this one, even for a professional researcher.
Their main message was simple.
Immune cell infiltration (especially, tumor-antigen-bearing T-cell clones) and types of gut bacteria are two important factors to assess clinical outcomes/survival.
I'll just drop one finding from the paper here.
If you have colon cancer, many things are out of your control. What kind of mutations the cancer carries, what kind of treatment options your oncologist choose or are available, how well your immune system is functioning, etc etc.
Immunotherapy is one way to reboot your anti-cancer immunity. Now it is a standard therapy option in oncologists' arsenal. Depending on the cancer and condition of your immune system, they can work remarkably well, or less so.
But gut bacteria is something you can influence through what you feed to them (= what you eat). In a sense, it is a (cancer) environment that you have some control over it.
There are several gut bacteria species associated with colon cancer and/or gut health. Fusobacteria and Ruminococcus gnavus are considered bad guys, while Akkermansia, Bifidobacterium lactis, Lactobacillus acidophilus are considered good guys.
I checked US Amazon. They have supplements for Akkermansia, Bifidobacterium lactis, and Lactobacillus acidophilus. How convenient.
In the paper they found a gut bacteria species Ruminococcus bromii as a bacteria species associated with high survival rate. R. Bromii is bacteria that can use resistant starch as energy source, and can generate butyrate, a chemical that can work against colon cancer cells.
The authors speculated that R. bromii help to optimize local immune infiltration and anti-cancer immunity.
With reservation that they only showed correlation and not causation, you can still take a leap of faith and try to feed R. bromii in your own gut.
Although US Amazon does not offer Ruminococcus bromii supplement (with a high impact publication to back it up, I'm sure someone is going to start selling it), there may be a few ways to feed R. bromii in your gut, for the people willing to take a leap of faith (come to think of it, how unscientific this sounds).
One way is, as suggested by the authors, to eat castalagin, a type of ellagitannin rich in Oak tree and Camu Camu berry.
Camu Camu is an exotic berry cultivated in South America, like Brazil and Peru. According to another paper (Messaoudene et al., Cancer Discovery (2022), 12, 1070-), castalagin can directly bind to R. bromii and possibly helping them to increase in the gut.
Another is to eat peanuts. (....seriously, I need to confirm this one).
Out of curiosity, I picked up a bag of peanuts at a local store and ordered Camu Camu berry powder from Amazon, although I don't have colon cancer (hopefully not). Another n=1 human experimentation on myself. Wonder how would Camu Camu berry taste?
Actually, the gut bacteria modulation approach probably is like a balancing act. I'll monitor how it is working for me, and if something is wrong, I'll just toss it.
Their datasets are missing racial information. As mainly European cohort (presumably), their biology may or may not be the same from biology of colon cancer patients in US or in Asia.
But their report is most comprehensive colon cancer dataset available to date. As the datasets are deposited to depositories and are publicly available, I am going to check them out as a summer project.
If you read the whole paper, you'd notice that this research did not come in one-go. They got funding for this analysis, then another funding for another analysis. We can so relate. Rome wasn't built in a day.
