Know what cancer is and how cancer cell cripple immune system
Cancer is a disease characterized by the development of abnormal cells that divide uncontrollably and never cease to proliferate while normal cells only divide a finite number of times before they die or reach a perpetual state of evolution. Normal cells proliferate and stop growing when they come in contact to nearby tissue (contact inhibition) while cancer cells ignore and invade nearby tissue.
Cancer cell may look very different from normal cells, different size, may be larger or smaller, abnormally shaped and nucleolus (control center) may have abnormal cells. Cancer cell can pass easily through smaller gaps as well as applying a much greater force on its environment as compared to other cells. It often has the ability to spread throughout the body using the blood or lymphatic system and destroy healthy tissue by invasion. Tumours can grow and interfere with digestive, nervous or circulatory system and can also release hormone that alter body function.
Cancer is the cause of increased morbidity and mortality worldwide. The most common sites of cancer among men are lung, prostrate, colon, rectum, stomach and liver, while in women the common sites are breast, colon, cervix, ovary, and stomach.
Cancer occurs when a cell’s gene mutation that occur after birth (not inherited) which make the cell unable to correct its DNA damage and unable to commit suicide (called apoptosis or natural death). A number of forces can cause gene mutation such as smoking, radiation, virus, carcinogenic chemicals, obesity, hormones, chronic inflammations and lack of exercise.
General symptoms and signs include fatigue, lump or area of thickening that can be felt under the skin, weight changes (loss or gain), change in bowel or bladder habits, persistent cough or difficulty in breathing, hoarseness of voice, persistent unexplained fever, joint pain or bleeding. The symptoms and signs will vary depending on what part of body is affected.
Immune system is comprised of two components: physical barrier and innate immune cells.
Physical barriers include our skin, gastric (stomach) acid, and hairs in the nose and ears. These physical barriers play an important role in keeping our body healthy.
Innate immune cells, called neutrophils and monocytes are critical for immune system. These cells are first responders and they work to gain immediate control of the situation and sends appropriate back up to adaptive immune system.
Adaptive immunity– It is made up of B-cells and T-cells, which have special memory function. When they found dangerous germs or any type of cancer cells ever pops up in your body, the B-cells and T-cells can recognized them immediately and move for vicious attack. So, both are essential for the effectiveness of the immune system.
Each of us is born with an intricate defense system that work to protect our bodies against illness and disease. The immune system is made up of network of cells and organs that work together to detect potential threats within the body and react to fight those invaders. If all is working correctly, invaders are identified and the appropriate.
Cancer cells cripple the immune system by sending out biological ‘drones’ to fight and thus survive. Drones are small vesicles called exosomes, which are tiny lipid vesicles with a diameter of less than 1/100th of red blood cells, circulating in the blood and armed with protein called PD-L1 that cause T-cells to tire before they have a chance to reach tumour. Since single tumour cells is able to secrete many copies of exosomes, thus interaction between PD-L1 exosomes and t-cells provides a highly effective system to suppress anti-tumour immunity in the whole body. This explain why cannot patient have weakened immune system.
Cancer patient usually respond to anti PD-1 therapy that disrupts immune suppression to fight tumours. The anti PD-1 therapy blocks interaction between PD-1, a protein on the surface of T-cells and PD-L1, counterpart molecule on tumour cells thus reviving T cells and allowing them to unleash killing power on the tumour.
Cancer risk can be reduced by avoiding by avoiding tobacco, limiting alcohol intake, limit UV ray exposure from sun and tanning bed, maintaining healthy diet and level of fitness and seeking regular medical care.