New (mostly Australian) study [1]:
"Acute effect of high-intensity interval aerobic exercise on serum myokine levels and resulting tumour-suppressive effect in trained patients with advanced prostate cancer"
So they took nine mCRPC men & gave them 34 minutes of "a high-intensity interval exercise session on a cycle ergometer". 34 minutes? An Australian hour, perhaps.
And then they drew blood and tested it on DU-145 cells.
Purist will want to know if the men lived longer than controls. Alas we might never know, but the DU-145 cells did not do well.
DU-145 (from a brain met) is one of the big three cell lines, with LNCaP (lymph node) & PC3 (bone).
I can't think why they would choose DU-145 over PC-3, but "DU145 are not hormone-sensitive and do not express prostate-specific antigen (PSA). DU145 cells have moderate metastatic potential compared to PC3 cells, which have high metastatic potential." [2]
"There was a significant elevation of SPARC (19.9% ...), OSM (11.5% ...), IL-6 (10.2% ...) and IL-15 (7.8% ...) in serum collected immediately after exercise compared to baseline, returning to baseline after 30 min rest.
SPARC (Secreted Protein Acidic and rich in Cysteine), aka Osteonectin. "... plays a vital role in bone mineralization, cell-matrix interactions, and collagen binding. Osteonectin inhibits tumorigenesis in mice. Osteonectin can be classed as a myokine, as it was found that even a single bout of exercise increased its expression and secretion in skeletal muscle in both mice and humans." [3]
OSM [4?]
IL-6 - "Interleukin 6 ... acts as both a pro-inflammatory cytokine and an anti-inflammatory myokine." [5]. "IL-6 ... was the first myokine found to be secreted into the blood stream in response to muscle contractions." [3]
IL-15 - "Interleukin-15 stimulates fat oxidation, glucose uptake, mitochondrial biogenesis and myogenesis in skeletal muscle and adipose tissue. In humans, basal concentrations of IL-15 and its alpha receptor (IL-15Rα) in blood have been inversely associated with physical inactivity and fat mass, particularly trunk fat mass. Moreover, in response to a single session of resistance exercise the IL-15/IL-15Rα complex has been related to myofibrillar protein synthesis (hypertrophy)." [3]
From the new paper [1]: "This study provides preliminary evidence for an acute exercise-induced myokine response and tumour growth suppression in serum after a bout of high-intensity interval exercise in patients with advanced PCa."
[1] pubmed.ncbi.nlm.nih.gov/364...
[2] en.wikipedia.org/wiki/DU145
[3] en.wikipedia.org/wiki/Myokine
