oncolysis
Meaning of oncolysis: Naming an outcome and not a method, the word covers anything that leaves cancer cells broken open, from a drug to a virus.
Definition of oncolysis
Oncolysis is the destruction or breaking apart of cancer cells, whatever brings it about. Chemicals, physical energy such as focused sound waves, radiation and certain viruses all produce it, and the word describes the result rather than the route to it. It is used both for what a treatment achieves and for the rare breakdown of a tumor with no treatment at all.
How oncolysis is built
- onc/o Combining form · Greek tumour, mass
- -lysis Suffix · Greek breakdown, destruction, separation
A medical term is read from its ending backwards: the suffix first, then the prefix, then the root. See all 223 word parts.
What can produce it?
| Route | How the cell is destroyed |
|---|---|
| Chemical | Cytotoxic drugs damage the cell beyond what it can repair |
| Physical | Focused ultrasound and other energy delivered directly into a tumor |
| Radiation | Breaks in DNA that the cell cannot survive when it next divides |
| Biological | A virus multiplies inside the cell until the cell bursts |
Because the word fixes on the outcome, it carries no judgment about whether the outcome is wanted. Spontaneous oncolysis, in which a cancer retreats without any treatment, is genuine but uncommon and is best documented in melanoma, kidney cancer and neuroblastoma. It is thought to reflect the immune system finally recognizing the tumor rather than anything happening inside the cells alone.
How do oncolytic viruses work?
A virus reproduces by taking over a cell's machinery, and healthy cells resist by switching on an interferon response that shuts that machinery down. Many cancer cells have already disabled that response, because it also restrains their own growth, and an oncolytic virus exploits the gap: it replicates freely in the tumor and poorly in normal tissue. Modified viruses narrow the difference further, and some carry an added gene that pulls immune cells toward the tumor. The cell is destroyed by the virus filling it, but the therapeutic effect is not only the killing. Debris released from a cell that dies in this messy way exposes tumor proteins in an inflamed setting, which is precisely the setting in which the immune system learns to attack them, so untreated deposits elsewhere may shrink too. A modified herpes virus injected directly into melanoma deposits is approved for that skin cancer, and others remain in trials.
What happens when many cells break down at once?
Rapid destruction of a large, fast-dividing cancer spills the contents of those cells into the blood faster than the kidneys can clear them. Potassium, phosphate and the uric acid formed as released DNA is broken down all rise together, and the combination can disturb the heart rhythm and injure the kidneys. This is tumor lysis syndrome, a hazard of treatment working rather than failing. Its existence is a reminder that oncolysis names the breakdown alone and says nothing about whether the person is better for it.
Used in a sentence
Researchers studied the oncolysis produced by the modified virus in laboratory models of the tumor.
Good to know
Oncolysis describes the outcome of cancer cell destruction rather than a single specific method, so the term applies equally to a chemical, physical, or viral mechanism.
Word origin
Where “oncolysis” comes from
Formed from onco-, Greek for tumor or mass, and lysis, meaning a loosening or breaking down.