# Proliferation

Source: https://onco.cc/terms/proliferation/  
OnCo record `proliferation` (Term). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

Rapid multiplication of cells. A tumour's proliferation rate, often measured by the marker Ki-67, tells you how fast it is growing and how it may respond to treatment.

## Summary

Proliferation is the net result of cell division outpacing cell death; in a healthy tissue the two are balanced, and a tumour is a tissue where the balance has tipped. Pathologists estimate it by counting cells in mitosis or staining for Ki-67, a protein present only in dividing cells; a high index means an aggressive tumour that may respond well to chemotherapy but relapse quickly, a low index a slower tumour that may suit hormone therapy or watchful waiting. 'Sustaining proliferative signalling' is the first hallmark of cancer, and 'anti-proliferative' describes any drug that slows division rather than killing cells outright.

## Fields

- Kind: Term
- Last checked: 2026-09-09
- Also known as: proliferate; proliferating; proliferative; cell proliferation; anti-proliferative; antiproliferative; Ki-67; Ki67; proliferates

## Sources

- Wikipedia: https://en.wikipedia.org/wiki/Cell_proliferation
- Wikipedia: https://en.wikipedia.org/wiki/Cell_proliferation

## Connected records

- terms: [Cell cycle](https://onco.cc/terms/cell-cycle/), [Cell division](https://onco.cc/terms/cell-division/), [Grade](https://onco.cc/terms/tumour-grade/), [Growth signal](https://onco.cc/terms/growth-signal/), [Hallmark: sustaining proliferative signalling](https://onco.cc/terms/sustaining-proliferative-signaling/), [MIPI (Mantle Cell Lymphoma International Prognostic Index)](https://onco.cc/terms/mipi/)
- targets: [Ki-67 (MKI67)](https://onco.cc/targets/mki67/)
- biomarkers: [Ki-67 index (proliferation by IHC)](https://onco.cc/biomarkers/ki-67-index/)

---
JSON: https://onco.cc/api/v1/entities/proliferation.json