Alcohol’s effects on microRNA (miR)-200b-3p. Adolescent and adult MMTV-Wnt1 mice received chronic alcohol exposure as described above. As tumor size reached maximal diameter of 20 mm, the mice were sacrificed, and mammary tumor tissues were dissected for the analysis of miR-200b-3p expression. For adolescent alcohol exposure, n = 9 for both control and alcohol-exposed group. For adult alcohol exposure, n = 11 for both control and alcohol-exposed group * significant difference from controls, p < 0.05.