Chemotherapy is treatment by medication which is fundamentally poisonous to all cell types but affects cancerous cells more due to their faster growth rate. Unlike healthy adult cells, which multiply relatively slowly, malignant cells are characterised by unchecked rapid cell division. Medication treatments aim to exploit this difference to target mainly malignant cells and therefore shrink the tumour. The ideal situation would be the death of all the cancer cells and survival of all normal cells. It rarely works out that well.
Although affecting cancerous cells more severely, chemotherapies can also act on healthy cells due to the inherent cell toxicity of all drugs used in chemotherapies. Consequently side effects often occur, such as hair loss and fatigue, however accompanying treatments may alleviate some of these issues.
A variety of chemotherapy drugs exist that are classified according to how they work. Classes include so-called DNA crosslinking agents, antimetabolites and different forms of protein inhibitors.
DNA crosslinking agents interfere with genetic material found within every cell. Antimetabolites cause cell death by mimicking and consequently replacing the molecules needed for cell growth. Finally, protein inhibitors interact with structures in the cell and prevent them from functioning.
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