Increased expression of PCNA, VEGF and COX-2 in the arthritic PyV MT tumors. A-C: Higher number of PCNA positive cells in the tumors of arthritic PyV MT versus non-arthritic PyV MT. D-F: Increased expression of VEGF in the arthritic PyV MT tumors. The images of tumors were taken at 200× magnification. Brown staining represents positive PCNA and VEGF staining. Representative of n = 10 mice is shown. G: Western blot analysis of COX-2 expression. β-actin serves as control for equal protein loading.