Introduction
Cancer cells differ significantly from normal cells in behaviour and function.
These properties allow them to grow uncontrollably, invade tissues, and evade normal regulatory mechanisms.
Understanding these characteristics is essential for developing targeted therapies.
Properties of Cancer Cells
Formation of Tumour
Uncontrolled Division: Cancer cells divide continuously without responding to normal growth-regulating signals.
Mass Formation: This leads to the accumulation of cells, forming a tumour.
Types of Tumours:
Benign (non-invasive).
Malignant (invasive and can spread).
Loss of Contact Inhibition
Normal Cells: Stop growing when they come into contact with each other, maintaining an organised structure.
Cancer Cells: Ignore this inhibition and continue dividing, piling up to form disorganised masses.
Result: Enables uncontrolled tissue growth and tumour expansion.
Anchorage Independent Growth
Normal Cells: Require attachment to a surface (e.g., extracellular matrix) for growth and survival.
Cancer Cells: Can grow without being anchored to a substrate.
Significance: This ability allows cancer cells to survive in suspension and spread through the bloodstream or lymphatic system.
Immortality
Normal Cells: Have a finite number of divisions due to the Hayflick limit.
Cancer Cells: Avoid senescence (ageing) and apoptosis (programmed cell death), allowing them to divide indefinitely.
Mechanism: Linked to telomerase activation and resistance to apoptosis.
Angiogenesis : Formation of Blood Vessels
Definition: Cancer cells stimulate the growth of new blood vessels to supply nutrients and oxygen to the tumour.
Process: Secret angiogenic factors like VEGF (vascular endothelial growth factor).
Impact:
Supports tumour growth.
Facilitates metastasis by providing routes for cancer cells to enter the bloodstream.
Telomeric Activity:
Telomeres: Protective caps on chromosomes that shorten with each cell division in normal cells, leading to senescence.
Cancer Cells: Activate telomerase, an enzyme that rebuilds telomeres, preventing them from shortening.
Result: Enables indefinite cell division, contributing to immortality.
Conclusion:
Cancer cells exhibit unique properties such as uncontrolled growth, loss of regulatory mechanisms, and survival advantages.
These traits not only allow them to proliferate and invade but also make them challenging to treat.
Targeting these properties through therapies (e.g., anti-angiogenic drugs or telomerase inhibitors) is a focus of modern cancer research.