Chapter 1 - Introduction to cancer biology

Abstract

Cancer refers to a heterogeneous multifactorial disease that continues to be a main cause of death worldwide. Several levels of codependent networks, including cellular, tissue, and systemic structures, are involved in the pathological process of converting normal tissues into cancerous ones. Malignant tumors are defined by three distinct cancer tissues: the primary tumor, local cancerous cells, and distant metastasis. Darwinian theory on cancer development proposes that the formation of cancer cells first occurred through gradual selection and development of advantageous properties found in malignant cells with heritable genetic mutations. Cancer was initially distinguished by six major hallmarks: self-sufficiency in growth signals, insensitivity to antigrowth signals, apoptosis evasion, limitless replicative potential, sustained angiogenesis, and tissue invasion and metastasis, as posited by Hanahan and Weinberg [or reference that study], who updated their view from time to time. Six years after Hanahan and Weinberg’s initial findings, Fouad and Aanei expanded on their cancer hallmarks and presented more pathological processes, including altered stress response favoring overall survival, metabolic rewiring, an abetting microenvironment, and immune modulation. Recently, the defining evolutionary hallmarks have expanded to include genomic and epigenetic diversification, resistance to cell death, modulation of the microenvironment, and cellular plasticity. Although biology today benefits from a host of technological developments, few such developments have demonstrated the potential for paradigm-changing impacts on basic research, drug development, and clinical medicine as strongly as nanotechnology. Nanotechnology offers a wide range of tools and applications operating at the subcellular level to interact with biological processes.