Sometimes this control can go wrong. If that happens in just a single cell, it can replicate itself to make new cells that are also out of control. These are cancer cells. They continue to replicate rapidly without the control systems that normal cells have.
What part of cell cycle does cancer affect?
These cells are said to be aneuploid. Errors may occur during the DNA replication resulting in mutations and possibly the development of cancer. Cells have mechanisms to correct errors due to faulty DNA replication. Many chemotherapy agents target the S phase of the cell cycle.
What is the connection between cancer and cell replication?
DNA replication errors, especially those occurring at regions that are hard to replicate, called fragile sites, can cause breaks in DNA. This can lead to cancer, primarily by making it more likely that fragments of chromosomes rearrange themselves, activating genes that lead to uncontrollable cell division.
How do cancer cells pass checkpoints?
In normal proliferating cells, initiation of these processes is controlled by genetically-defined pathways known as checkpoints. Tumors often acquire mutations that disable checkpoints and cancer cells can therefore progress unimpeded into S-phase, through G2 and into mitosis with chromosomal DNA damage.
What problems are associated with cancer cells?
These include self-sufficiency in growth signals, insensitivity to growth-inhibitory (antigrowth) signals, evasion of programmed cell death (apoptosis), limitless replicative potential, sustained angiogenesis, and tissue invasion with metastasis .
How do cancer cells behave differently from healthy ones?
In contrast to normal cells, cancer cells don’t stop growing and dividing, this uncontrolled cell growth results in the formation of a tumor. Cancer cells have more genetic changes compared to normal cells, however not all changes cause cancer, they may be a result of it.