Platinum-based chemotherapy and Pol η protein expression in head and neck squamous cell cancer.

<p>Upper row represents nuclear staining of Pol η in HNSCC before chemotherapy. Lower row represents Pol η staining in tissue obtained from the same areas of original tumors after chemotherapy. Case 1) Pol η staining level up-regulated post chemotherapy. Case 2) Pol η staining level down-regulated post treatment. Case 3-4) Pol η staining level remained same intensity post treatment (immunoperoxidase, original magnification x200).