Is acanthosis nigricans able to be cured to where the dark skin will become normal?

Possibly: If you truly have acanthosis nigricans, it's often very difficult to treat. Make sure it doesn't just wipe off with an alcohol wipe, though! if it does, you may not actually have an--see your dermatologist. Some lasers and prescription creams may help. Most importantly, the underlying cause needs to be identified and treated as this might clear the skin completely!

Acanthodians: If it is associated with Insulin resistance ie elevated fasting Insulin levels then medication and weight loss may help.