Cancer refers to the condition in which abnormal cells display uncontrolled growth within the body. The condition occurs when the body’s normal immune mechanism fails to function properly. The abnormal cells and the old cells are no longer eliminated by the body’s immune system but rather multiply fast to form new abnormal cells. These abnormal cells may form a mass known as tumour. However, not all tumours are cancerous, they may also be benign. Cancer can affect any part of the body, including blood, bone marrow and lymph nodes. Mature cancer cells can also spread to the other parts of the body, through a process termed as metastasis.
Cancer is a disease associated with genomic instability and damage to DNA. Over 90% of cancer is found to be associated with genome alteration, of which some are inherited while some may be sporadic. Inheritance of cancer is due to inheritance of the aberrant genetic alteration. The genetic mutation may promote rapid and abnormal growth of cells without the functioning of tumour suppressor genes that are capable of terminating cell growth. Exposure to carcinogens such as chemicals (e.g., asbestos, benzene, etc.), radiation, and fine particulate matter is also cited as the common causes of cancer. In addition to the carcinogens, several risk factors have been considered. For example, age, gender, lifestyle (including sun exposure, smoking and drinking habits, etc.), family history (genetic inheritance), genetic disorder, surrounding environment (including exposure to harmful chemicals, smoke, UV radiation, etc.), exposure to certain viruses (e.g., Epstein-Barr virus and HIV is associated with a higher risk of Hodgkin and non-Hodgkin lymphoma). Thus, there is no single cause for cancer. In fact, scientists believe that interaction of multiple factor such as genetic, environment, and constitutional makeup leads to the development of cancer.
Cancer refers to a group of diseases, all of which show uncontrolled replication of abnormal cells at rapid rate. Cancers may be classified based on their source or origin. Mixed types of cancers have also been reported. Cancer has been classified into the following broad categories:
Cancer Biology is a foundational course designed for individuals with backgrounds in life sciences and for those looking to expand their repertoire of knowledge and skills to progress in their careers. This course is precursor to Immunogenomics, a more advanced and specialised area that develops on some of the concepts introduced in Cancer Biology.