We present a mathematical, agent-based, model that describes the progression of a brain tumor by capturing the interplay between processes occurring at the intracellular and tissue levels. Specifically, we focus on the temporal-spatial distribution of key biochemical cues (e.g., nutrient, growth factors) and the intracellular signaling pathways (e.g., PI3K-Akt and MAPK pathways) underlying the tumor growth, tumor cell migration and angiogenesis processes. We employ the model to explore the effect of possible migration mechanisms on the growth and invasion properties of the tumor. Simulation results show that the model is able to recapitulate in silico the morphology of brain tumors. We believe that the proposed modeling base (after further development and refinement) could ultimately help identify spatio-temporal dependent targets for tumor suppression that may otherwise remain concealed.