In the tumor sections from mice injected with equal amount of cells (1 × 106), the cell proliferation, as evaluated by cell mitosis (Fig. 4I, upper) and the ratio of Ki-67-positive tumor cells (Fig. 4I, lower), was also accelerated in xenografts from RBM5-AS1-overexpressing group while attenuated in tumors of RBM5-AS1-koncked down group. The gene discussed is RBM5; the disease is neoplasm.