You can't really tell what something does with just one instruction. That's basically the same as:
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*(DWORD*)(0x111111+0xC) = EAX;
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Assuming whatevers in ESI is 0x111111, it could be anything. Also, 0xC ( 12 ) because in assembly everything goes by single bytes, so I just had to make a small conversion.
I don't think I'm understanding you here though, are you trying to find what's in ESI all the time? Or...