The cure to depression is a) calm the mind via the breath and once that is complete, usually after days of effort, and b) to observe your physical sensations from moment to moment without reacting to them in order to see Reality as it is.
If not a part of a 'solution' as such, sometimes they simply help people cope for a little while, which can be valuable.
Cure, though? Absolutely not.
http://en.wikipedia.org/wiki/2_%2B_2_%3D_5#In_popular_cultur...
There.Are.Four.Lights