Viagra and cancer metastasis pathways
OncologyComments
We saw this with the PDE5 inhibitors and neuroprotection claims a few years back. The unknown pathway usually turns out to be a non-specific effect when you drench cells in concentrations they would never see in a human body.
Most of the patients who could actually benefit from this are already on a cocktail of meds that might interfere with cholesterol transport. It is one thing to stop a pathway in a petri dish, but quite another when the patient is also taking a statin.
That is such a good point... I wonder if this would actually be more effective for people who cannot take statins for some reason... or if the interaction would just cancel everything out?
To your point about statins, I wonder if the sildenafil is targeting the late endosomal cholesterol transport or something more upstream. Does the study specify if they controlled for HMG-CoA reductase inhibitors in their cell lines?
check the supplemental data; the n is under 20.
Even with a small n, could this still be a valid proof-of-concept for the mechanism itself? If the pathway is genuinely new, the initial discovery might be biologically significant regardless of the statistical power for clinical efficacy.