In: Biology
2. Transient and acute inflammation is important for the induction of an anti-tumor immune response while chronic inflammation promotes tumor growth. Based on this knowledge explain a higher incidence of cancer in the aging population.
Please type answer, written answers are hard to read.
2. Inflammation results from host response to trauma or as defense mechanism against invasive organisms or non-biological xenobiotic agents. It evokes inflammatory cells (macrophages, neutrophils, monocytes, dendritic and mast cells) to invade at the site of infection or wound establishing an `inflammatory microenvironment' that leads to the death and degradation of the organism, agent or affected cells.
Progression of age is associated with compromise of immune system. In humans, aging leads to decrease in humoral and cellular immune responses which leads to increase in the incidence and intensity of various diseases and ailments, causing inflammation to build as a response towards infections.
In humans, B cell percentages and numbers significantly decrease with age. Further, antibodies generated in old humans are less protective compared with the antibodies generated in the young individuals. Therefore, the normal functioning of the immune system is severely compromised in aged individuals which together with many other complex cellular malfunctions eventually leads to the development and progression of cancer because the initiated cancer cells could easily evade the immune surveillance.
This is the reason why higher incidence of cancer are observed in the aging population because of compromised immune system and chronic inflammation leading to tumor formation. Aged residential phagocytes such as macrophages and neutrophils within host sometimes exhibit inappropriate respiratory burst with concomitant release of reactive nitrogen and oxygen intermediates which may decrease the ability to destroy pathogens. Thus, minimum counter effect is seen against cancerous cells in aged population.