Cells, DNA, and Tissues
Educational orientation
Source-checked: 2026-06-05. This page is for conceptual learning, not individual interpretation.
Core Idea
Cancer begins at the cell level but is shaped by tissue context. Cells carry DNA, DNA contains genes, and genes help control growth, repair, death, identity, and communication. Cancer-related changes can alter those controls, but the same DNA change may matter differently in different tissues.
Tissue organization matters because cells are not isolated software objects. They receive signals from neighboring cells, immune cells, blood vessels, oxygen levels, nutrients, and the extracellular matrix.
Essential Vocabulary
- Cell: the basic living unit of tissue.
- DNA: the molecule carrying genetic instructions.
- Gene: a DNA segment with a biological function.
- Tissue: organized cells with shared structure and role.
What This Does Not Mean
Cancer is not explained by one mutation alone. Many cancers reflect accumulated changes plus tissue-level selection.
Builder/Data Lens
Molecular data without tissue context is easy to overread. A variant table, image, or expression matrix needs sample provenance.
Go Deeper
References
- National Cancer Institute. What Is Cancer?
- National Cancer Institute. The Genetics of Cancer