Cardarine: Cancer Growth Through Increased ATP

/u/soulobliteration sent me this link, https://www.reddit.com/r/DrugNerds/comments/a79c0s/the_role_of_cardarine_and_ppar%CE%B4_in_the_initiation/which offers a recent (2018) view on cardarine and cancer. Appreciate the link, it was a good read - thank you for sharing it!

The researchers who wrote this analysis make an argument that PPAR-d (the receptors that cardarine bind with) have roles depending on the context. While PPAR-d allows normal cells (e.g., muscle cells and pancreatic cells) to better cope with adverse nutrient and energy pressures, PPAR-d overexpression or hyperactivation can lead to promotion of inflammation and tumorigenesis.

As we know, cardarine was developed to help address metabolic disorders and help offset damage from fatties being unable to put a fork down. However this altered metabolic environment (via PPAR-d overexpression) could also promote the survival of cancer cells. Their example and argument is that overexpression of PPAR-d increases fatty acid oxidation (what causes the increase in stamina and reduction in fat) can lead to increased ATP production. This provides cells, including cancerous ones, an additional energy source, allowing them to grow faster, and larger. Cardarine is highly effective at increasing fatty acid oxidation, hence their argument.

My layman understanding of this action is that this might make existing tumors worse, which is exactly what we see when using (inbred and cancer prone) lab rats. But yes, it still doesn't present in the human clinical trials, the primate studies (https://sci-hub.tw/https://www.ncbi.nlm.nih.gov/pubmed/11309497), or in any bro-dotes that I'm aware of. I'd also point out that fasting and cardio may also increase fatty acid oxidation, though I concede that the equivalence is not perfect.

The researchers are understandably cautionary, and the MOA they give us on tumorigenesis is valuable. Aside from that, I don't see anything new or further cause for alarm than already exists with this compound.