The II-V-I progression in minor (IIm7b5 - V7 - Im7)
The parallel minor key of a major key is practically (nearly) nothing else than the major key starting from the 6th scale degree. That means e.g. A minor is the parallel minor key of C major. When we name a chord progression by it's degrees - e.g. I V VIm IV - the degrees are normally based on the major key. But when you say "two-five-one in minor", you are talking about the scale degrees of the minor scale.
V7 also in minor on the 5th scale degree
There's one difference in the parallel minor key, when you play chords: if the chord on the 5th degree (originally m7) resolves into a chord on the 1st degree, you'll play a dominant 7th chord instead of a minor 7th chord. In the key of A minor e.g. we'll change Em7 to E7, when it comes to a two-five-one progression.
Chord extensions (tensions)
Like in the II-V-I in major you'll find a lot of chord extensions in the examples: 9, 11 and 13 are tones, that result from stacking more thirds over the basic chord tones 1, 3 (m3), 5 (b5) and 7 (maj7).
But this time we're also dealing with altered tensions: in minor I-V-I progressions we even have to use altered tensions b9, #9 and b13 (instead of 9 and 13).