The study, that is so often referred to, subjected rats to supraphysiological dosages of 10mg/kg of body, or to put that in perspective, a 200lb man (roughly 90 kg) dosing around 900mgs of GW-501516 per day. These doses defy any sensible logic and, therefore, hold no standing at the suggested dosage of 20mg a day.
The study cited above, rats were given the equivalent of a 900mgs dose of GW; this would be comparable to taking 14,625 mgs of aspirin per day. Usually, 325 mgs of aspirin is 1 dose (1 pill). This dose of aspirin could literally KILL you, forget cancer!