✍🏻 Sara Norris |BSc Medical Biochemistry Student, University of Leeds
What is Cancer? 🩺
Cancer is the leading cause of death worldwide.
Cancer is a group of diseases characterised by the uncontrolled growth and spread of abnormal cells in the body. Normally, our cells grow and divide in an orderly manner, but in cancer, this process is altered. The accumulating abnormal cells form a mass known as a tumour. These tumours can be benign (not cancerous) or malignant (cancerous).
Malignant tumours have the potential to invade nearby tissues and spread to other parts of the body via the bloodstream or lymphatic system, through a process known as metastasis. Cancer can occur in virtually any tissue or organ, and its impact on health depends on the type of cancer and the stage at which it is diagnosed.
Caused by genetic mutations, cancer disrupts the normal regulation of cell growth, leading to the formation of masses that interfere with the body's functions.
What is genetics?🧬
Genes are a basic unit of heredity in all living organisms, which are inherited from our parents.
Genetics is the branch of biology that focuses on the study of genes and heredity - the passing of traits from parents to offspring. Genes are the fundamental units of heredity and are composed of DNA (deoxyribonucleic acid), a complex that contains the instructions an organism needs to develop, grow and function. It is a double helix, located in the nucleus of every cell, and made up of pairs of molecules called bases, forming a unique code. It is this code that tells our bodies how to grow, function and stay healthy.
When cells divide, they duplicate this DNA. If duplication is successful, the new cells receive identical genetic information. But sometimes, tiny changes or mutations occur, introducing variety into the genetic code, for better or for worse.
How is cancer influenced by genetics?👨👩👧👦
Up to 10% of all cancers may be caused by inherited genetic changes.
Cancer is influenced by genetics in various ways, both through inherited genetic factors and the accumulation of mutations during an individual's lifetime. This includes:
Inherited Genetic Mutations
Some individuals inherit specific genetic mutations from their parents that increase their susceptibility to certain types of cancer. They are present in the germline cells (sperm or egg cells) and can be passed on to the next generation.
How are treatments for cancer influenced by genetics? 💉
Understanding the unique genetic makeup of each patient's tumour offers healthcare professionals valuable insights to guide treatment.
Traditional cancer treatments, such as chemotherapy and radiation, aim to eliminate rapidly dividing cells, including cancer cells. While effective, these treatments can also harm healthy cells, leading to side effects. Targeted therapies, on the other hand, focus on specific molecules involved in cancer growth and progression.
By analysing the genetic makeup of a patient's tumour, scientists can identify specific mutations or abnormalities driving the cancer. Targeted therapies are then designed to interfere with these specific molecular pathways, disrupting the cancer's ability to grow and survive. This approach not only enhances the efficacy of treatment but also minimizes damage to healthy cells, reducing side effects for the patient.
With advancements in genetic testing technologies, it is becoming increasingly feasible to analyse a patient's tumour at the molecular level. This allows healthcare providers to select treatments that are most likely to be effective for that specific patient, optimizing outcomes and reducing the need for trial-and-error approaches.
Edited by: Olivia Laughton | Content Editor | BSc Microbiology, University of Leeds