miR-34a Inhibits HNSCC Tumor Growth Figure 5. miR-34a inhibits tumor growth in vivo. Tumor cells transfected with miR-34a or SC were mixed with 100 ml of Matrigel and injected subcutaneously in the left and right flanks of SCID mice respectively (n = 5). Tumor volume measurements began on day 3 and continued twice a week until the end of the study. The length and width of the tumors were measured using a digital caliper and tumor volumes were calculated using the formula, volume (mm3) = L6W2/2 (length L, mm; width W, mm). After 18 days, tumors samples were carefully removed. A-B: Tumor growth curves for UM-SCC-74A and UM-SCC-74B respectively. *, represent a significant inhibition (p,0.05) of tumor growth in miR-34a group cells as compared to SC. C-D: Representative photographs of mice bearing UM-SCC-74A or UM-SCC-74B tumors. Green and red circles are used to highlights tumor cells transfected with scrambled control (SC) or miR-34a, respectively. E-F: Representative photographs for UM-SCC-74A and UM-SCC-74B tumors at day 18, respectively. G: miR-34a levels in UM-SCC-74A tumors at the end of the in vivo experiments. *, represent a significant difference (p,0.05). doi:10.1371/journal.pone.0037601.g005 PLoS ONE | www.plosone.org 7 May 2012 | Volume 7 | Issue 5 | e37601