The Sorcerer's metamagic features has the following general rules:
At 3rd level, you gain the ability to twist your spells to suit your needs...You can use only one Metamagic option on a spell when you cast it, unless otherwise noted.
The Empowered Spell metamagic states:
When you roll damage for a spell, you can spend 1 sorcery point to reroll a number of the damage dice up to your Charisma modifier (minimum of one). You must use the new rolls.
The Wand of Magic Missiles states:
While holding it, you can use an action to expend 1 or more of its charges to cast the magic missile spell from it.
My question is does the process of activating the Wand equate to the sorcerer casting the Magic Missile spell and thus it becomes a suitable target spell for enhancement using the Empower Spell metamagic? Or does the casting occur from the wand and not from the sorcerer, thereby rendering the spell invalid for metamagic enhancement?