9.14
Cancer Prevention
Several factors can increase the risk of cancer in an individual. About 50% of cancer cases can be prevented by adopting a healthy lifestyle, regular…
Cancer is a genetic disease caused by alterations in the critical genes that control cell growth and proliferation. However, there are many factors that can lead to such genetic changes in an individual.
For example, parents with cancer-causing mutations may pass these on to their children, predisposing them to cancer.
Such cases of hereditary cancer can be prevented with the help of genetic testing. It can help an individual assess the risk of developing cancer and decide a future course of action for screening and prevention.
Inherited genetic mutations such as these play a significant role in about 5 to 10 percent of all cancers.
However, there are also various lifestyle and environmental factors that can increase the likelihood of a person developing cancer.
For example, prolonged exposure to the chemicals present in tobacco smoke or atmospheric pollutants can increase the risk of cancer.
Upon inhalation, the polycyclic aromatic hydrocarbons or PAHs in the smoke react with metabolic enzymes present in the pulmonary cells, giving rise to reactive metabolites that can directly interact with DNA and induce genetic mutations. Such DNA damage can ultimately lead to tumorigenesis.
Besides tobacco smoke, other lifestyle-associated factors such as higher consumption of processed meat, obesity, lack of exercise, or excessive alcohol consumption are common causes of cancer. The incidence of such cases can simply be reduced by educating the general public on the benefits of adopting a healthier lifestyle starting at an early age.
In addition to lifestyle-associated risks, individuals may be exposed to cancer-causing agents present in their immediate environment. For example, prolonged exposure to UV radiation can lead to skin cancer, which can be prevented by reducing exposure to the sun and other sources of UV radiation, such as tanning booths.
Similarly, the best way to prevent cancer caused by other industrial or environmental chemicals, such as asbestos, is to take the appropriate steps like the use of PPE kits to prevent or reduce exposure.
Some viruses, such as the Hepatitis B virus and the Epstein-Barr virus, can play an important role in causing cancer in humans. Such viruses can either weaken the host immune system, directly damage the host cells’ DNA, or introduce oncogenes into the host cells.
Such virus-associated cancers can be prevented by avoiding exposure to the viruses or immunization against them.
View the full transcript and gain access to JoVE Core videos
Q1: What role do inherited genetic mutations play in cancer development?
Inherited genetic mutations account for approximately 5 to 10 percent of all cancers. Parents with cancer-causing mutations can pass these to their children, predisposing them to cancer. Genetic testing helps individuals assess their cancer risk and determine appropriate screening and prevention strategies for managing hereditary cancer.
Q2: How do tobacco smoke chemicals cause DNA damage and cancer?
Polycyclic aromatic hydrocarbons (PAHs) in tobacco smoke react with metabolic enzymes in pulmonary cells, creating reactive metabolites that directly interact with DNA and induce genetic mutations. Such DNA damage can ultimately lead to tumorigenesis. This mechanism demonstrates how environmental chemical exposure increases cancer risk.
Q3: What lifestyle changes can reduce cancer incidence?
About 50 percent of cancer cases can be prevented through healthy lifestyle choices including regular exercise, balanced diet, and weight management. Populations with vegetable and fruit-rich diets show reduced cancer incidence, while those consuming processed meat, animal fat, and high-calorie foods face increased risk. Daily exercise and proper nutrition are key preventive strategies.
Q4: How do plant compounds like flavonoids help prevent cancer?
Flavonoids and isoflavonoids are secondary plant metabolites with anti-cancer properties found in vegetables, fruits, and legumes like soybeans. These phytochemicals prevent cancer by inhibiting cell cycle progression, reducing oxidative stress, inducing detoxification enzymes, stimulating immune response, and triggering apoptosis in abnormal cells.
Q5: Why does physical activity reduce breast and colon cancer risk?
Regular exercise increases food movement through the intestine, reducing bowel lining exposure to mutagens and lowering colon cancer risk. Rigorous physical activity decreases circulating estrogen exposure to breast tissue, reducing breast cancer risk. Exercise also helps control obesity, which is associated with increased risk of multiple cancer types.
Q6: How can viral infections be prevented to reduce cancer risk?
Viruses like Hepatitis B and Epstein-Barr can weaken immune systems, damage DNA, or introduce oncogenes into host cells, causing cancer. Virus-associated cancers can be prevented through avoiding exposure to these pathogens or receiving immunization against them, providing effective protection strategies.
Q7: What environmental exposures require protective measures to prevent cancer?
Prolonged UV radiation exposure causes skin cancer and can be prevented by reducing sun exposure and avoiding tanning booths. Industrial chemicals like asbestos require appropriate protective equipment (PPE) to prevent or reduce exposure. Taking preventive steps against environmental carcinogens significantly reduces cancer development risk.