Key differences between cancer cells and normal cells

Normally, human cells grow and divide to form new cells and as the cells grow old or are damaged, they are replace with new cells. When this order of cell cycle breaks down and cells proliferate abnormally, they form tumors that can be cancerous or non-cancerous. Cancer is still a significant concern for public health as it can start anywhere in the human body, where it grows and spreads uncontrollably. Cancer cells are invasive and can invade nearby tissues or travel to distant places in the body to form new tumors, also called metastasis (1).

This article covers key points in which normal cells differ from cancerous cells (2,3).

Cancer cells

Normal cells

Cell division
Uncontrolled and deregulated growth
Cell division and growth is tightly regulated
Cell death/repair
Damaged cells that cannot be repaired remain alive and proliferate abnormally
Cell damage leads either to repair or cell death
Cell communication
Cells behave irresponsively of regulating signals coming from other cells


Cell behaviour is regulated by cell-cell contact and communication
Appearance under the microscope
Higher variability in cell size, darker appearance of the nucleus
Uniform appearance within the same cell type
Capacity to leave the tissue of origin, enter blood or lymphatic vessels to reach other tisseues and colonize them
Adhesion molecules prevent cells from detaching from their designed place and leave their tissue of origin
They are rather undifferentiated or less differentiated that their normal counterpart
They reach maturity and differentiate
Immune system invasion
They escape immune detection and inhibit immune response
The immune system recognizes and removes damaged and dead cells
Blood supply
The formation of new vessels called neoangiogenesis is a hallmark of cancer
Angiogenesis usually occurs as part of the normal development of a tissue



  1. Breitenbach M, Hoffmann J. Editorial: Cancer Models. Front Oncol. 2018 Oct 3;8:401. doi: 10.3389/fonc.2018.00401. PMID: 30338241; PMCID: PMC6178941.
  2. Zhu S, Wang J, Zellmer L, Xu N, Liu M, Hu Y, Ma H, Deng F, Yang W, Liao DJ. Mutation or not, what directly establishes a neoplastic state, namely cellular immortality and autonomy, still remains unknown and should be prioritized in our research. J Cancer. 2022 Jul 4;13(9):2810-2843. doi: 10.7150/jca.72628. PMID: 35912015; PMCID: PMC9330459.
  3. Chen P, Hsu WH, Han J, Xia Y, DePinho RA. Cancer Stemness Meets Immunity: From Mechanism to Therapy. Cell Rep. 2021 Jan 5;34(1):108597. doi: 10.1016/j.celrep.2020.108597. PMID: 33406434; PMCID: PMC7839836.