Representative images of each genotype of PyMT mice with mammary tumors obtained from 12-16-week old female (S1); Histological sections of the lungs from PyMT mice of different OGG1 genotypes (S2); OGG1 activity in mammary tumors isolated from B-nuclear, and D- mitochondrial fractions from PyMT/KO and PyMT/Tg animals (S3); LDH activity in mammary tumors isolated from PyMT/KO, PyMT/WT, PyMT/Tg and PyMT/ KOTg mice (S4).