Cancer is a complex and heterogeneous (systematic) disease that exhibits high levels of robustness against various therapeutic interventions. Due to the complex, heterogeneous, and evolving nature of cancer, it is essential for a system-oriented view to be adopted in order to understand the pathogenic mechanism of cancer which will eventually lead to the drug discovery and treatment of patients. This book not only provides new insights from system modeling and large scale experimental data, but also will allow the reader to perceive the systematic characteristics of cancer under some micro-environments. Based on the systems biology method and genome-wide high throughput data, the book presents the PPI network, gene regulatory network and epigenetic network as an integrated genetic and epigenetic cellular network of lung cancer, bladder cancer, thyroid cancer, colorectal cancer, and liver cancer to investigate their core signaling pathways of the carcinogenesis process to identify their corresponding significant carcinogenic biomarkers as drug targets for systems drug discovery and design. Consequently, the book presents the design of a multiple-molecule drug that can target these biomarkers for the therapeutic treatment of cancer with fewer side effects.