Cancer Biology: Mechanisms, Hallmarks, and Therapeutic Insights
Yegbeburu Oghenetega Sandra
Department of Human Anatomy, Faculty of Basic Medical Sciences, Southern Delta University, Ozoro, Delta State, Nigeria.
George Kelvin Nkem
Department of Human Anatomy, Faculty of Basic Medical Sciences, University of Delta, Agbor, Delta State, Nigeria.
Egwunyenga Michael Oge
Department of Human Anatomy and Cell Biology, Faculty of Basic Medical Sciences, Delta State University, Abraka, Nigeria.
Emetenjor Chukwudumebi Joel
Department of Anatomy, Faculty of Basic Medical Sciences, College of Health Sciences, Nnamdi Azikiwe University, Awka, Nnewi Campus, Nigeria.
Okoro Ogheneyebrorue Godswill *
Department of Human Anatomy, Faculty of Basic Medical Sciences, University of Delta, Agbor, Delta State, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Cancer represents a complex and highly heterogeneous group of diseases characterized by uncontrolled cellular proliferation, genomic instability, and the capacity for local invasion and distant metastasis. This review provides an integrated and contemporary overview of cancer biology, highlighting the intricate genetic, molecular, and environmental mechanisms that drive malignant transformation. At its core, carcinogenesis results from the progressive accumulation of mutations in two principal classes of genes: oncogenes, whose activation promotes uncontrolled cell growth and survival, and tumor suppressor genes, whose inactivation removes essential regulatory constraints on cell division and genomic integrity. The widely accepted Hallmarks of cancer framework serves as a conceptual foundation for understanding these processes, encompassing capabilities such as sustained proliferative signaling, evasion of growth suppressors, resistance to apoptosis, replicative immortality, induction of angiogenesis, activation of invasion and metastasis, and evasion of immune surveillance. Beyond genetic alterations, the tumor microenvironment including stromal cells, immune cells, and extracellular matrix components plays an important role in shaping tumor behavior, progression, and response to therapy. Additionally, nonmutational mechanisms such as epigenetic reprogramming and phenotypic plasticity further contribute to tumor heterogeneity and therapeutic resistance. Recent advances in molecular biology and genomics have significantly transformed cancer diagnosis and treatment, leading to the emergence of precision oncology. This includes targeted therapies directed at specific molecular alterations and innovative immunotherapeutic approaches, such as immune checkpoint inhibitors, which enhance anti-tumor immune responses. By linking molecular insights to clinical applications, this review emphasizes how evolving knowledge in cancer biology continues to drive the development of more effective and personalized strategies for cancer management.
Keywords: Cancer, hallmarks of cancer, oncogenes, tumor suppressor genes.