MHZ, NIW, OKT, PNQ,?

The first letters of the terms are consecutive letters. The third letter of each term is moved three steps backward to obtain the third letter of the successive term. The middle letters of the first, second, third and fourth terms are moved one, two, three, and four steps forward respectively to obtain the middle letter of the successive terms.
The order of above series given as - + 1 , + 2 , - 3
MHZ, NIW, OKT, PNQ, ( ? )
So ? = QRN ? 17 18 14
Hence , required answer will be QRN .