Genetics Behind Cancer

Cancer is one of the most prevalent diseases globally, with the Cleveland Clinic estimating that approximately one in every four individuals will develop cancer at some point in their lives. Its dangerous nature stems from the existence of over 200 distinct types of cancer, each targeting different ecosystems within the body. Medical professionals analyse specific genetic characteristics to identify the unique cancer that arises from particular genetic alterations in various parts of the body. However, genetics is not the sole contributor to cancer development; environmental and lifestyle factors also play a crucial role in the onset of malignancies.

As our cells divide, our genes can accumulate mistakes, known as mutations or variants. These mutations can occur at any point in our lives, whether through natural cellular processes or due to external factors such as tobacco smoke, high-energy radiation (x-rays), ultraviolet radiation from the sun or even certain substances found in food as well as chemicals present in our environment.

All these factors share a commonality: the presence of carcinogens, substances capable of altering DNA. Thus, cancer-related genetic changes can occur due to:

1. Random mistakes in our DNA during cellular division.

2. DNA alterations caused by environmental carcinogens.

3. Genetic inheritances from one or both parents.

Certain inherited faulty genes can increase an individual's risk of developing cancer. Typically, cells possess mechanisms to repair genetic faults. However, if the damage is severe, the cell may undergo programmed self-destruction, or the immune system may target and eliminate these abnormal cells, providing a protective barrier against cancer. Conversely, mutations in critical genes may disrupt a cell's ability to follow instructions, leading to uncontrolled multiplication, improper repair mechanisms, and eventual cancer development.

By examining family medical histories and records, physicians can make educated estimates regarding a patient’s cancer risk. Additionally, DNA samples can offer concrete insights into this risk. This method is applicable from pre-conception through post-mortem and can help identify specific pathogenic variants that might not present any symptoms, revealing information not captured in previous medical records.

Cancer is fundamentally a genetic disease caused by alterations in genes that regulate cellular behaviour, including growth and replication. Genes, which are sections of DNA, serve as the basic units of inheritance, passed from parents to offspring, encoding the information necessary for physical and biological traits. Most genes code for specific proteins or protein segments, each with distinct functions within the body. Researchers have identified numerous DNA and genetic mutations that contribute to the formation, growth, and spread of cancer.

DNA changes, whether resulting from random errors or carcinogen exposure, can occur throughout our lives, even during foetal development. While most genetic changes are harmless on their own, the accumulation of these changes over many years can transform healthy cells into cancerous ones. The majority of cancers arise by chance through this gradual process.

For a healthy cell to become cancerous, scientists believe that multiple DNA changes must occur. Individuals who inherit cancer-related genetic changes may require fewer additional alterations to develop cancer, although not everyone with these changes will necessarily experience cancer.

As cancer cells continue to divide, they accumulate more DNA changes over time. Interestingly, two cancer cells within the same tumour can exhibit different DNA alterations, and every person with cancer possesses a unique combination of DNA changes.

The advent of innovative technologies such as artificial intelligence, CRISPR, and robotic surgery has made cancer treatment more effective than ever before. Researchers have come to realize the potential of rapidly altering the genetic code of living cells, with CRISPR functioning like a pair of precise scissors that can delete, insert, or edit specific DNA segments within cells. This ground-breaking gene-editing tool emerged from a curiosity-driven project investigating how bacteria combat viruses. For example, a patient with prostate cancer may require prostate gland removal, a procedure that once necessitated a lengthy incision but can now be performed using robotic arms that make smaller incisions. Surgeons operate these robotic arms from a specialized console that provides real-time, magnified views of the surgical area. Robotic surgery typically results in less blood loss and pain, allowing patients to potentially leave the hospital as soon as the day after the procedure.

These futuristic advancements have transformed cancer treatment, inspiring patients to embrace the philosophy expressed by Dave Pelzer: “You can be a victim of cancer, or a survivor of cancer. It’s a mindset.” Through continued research and innovation, the fight against cancer is becoming increasingly hopeful for everyone.

Reference list

Cancer Research UK (2019). Genes, DNA and cancer. [online] Cancer Research UK. Available at: https://www.cancerresearchuk.org/about-cancer/what-is-cancer/genes-dna-and-cancer.

National Cancer Institute (2021). The Tech Revolutionizing Cancer Research and Care - National Cancer Institute. [online] www.cancer.gov. Available at: https://www.cancer.gov/news-events/nca50/stories/technologies-and-innovations#:~:text=Technologies%20and%20innovations%20like%20CRISPR.

www.mskcc.org. (n.d.). Cancer Genetics & Genomics | Memorial Sloan Kettering Cancer Center. [online] Available at: https://www.mskcc.org/research-areas/topics/cancer-genetics-genomics.

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www.sciencedirect.com. (n.d.). Cancer Genetics | Journal | ScienceDirect.com by Elsevier. [online] Available at: https://www.sciencedirect.com/journal/cancer-genetics.