Tumors were processed for immunohistochemistry as previously described (24 (link)). Ki67 (CST #9027, 1:400) antibody was used and bound antibodies were detected using the VECTASTAIN Universal Kit/HRP (Vector Laboratories) and 3,3’-diaminobenzidine substrates. Images are shown at a magnification of 20X and were quantified in three separate areas by counting the number of positive cells and creating an average and standard error that is presented in graphic form.