Causes of Tumors
Although genetic defects and environmental factors are suspected of contributing to the development of tumors, scientists do not know the causes of primary tumors yet. Although genetic defects and environmental factors are suspected of contributing to the development of tumors, at this time, the initial cause of tumors is unknown.
Cell division is regulated by the tumor suppressor genes. These genes also help repair any damage caused to the DNA. Tumor suppressor genes are constantly at war against the cancer-causing genes called oncogenes. When tumor suppressor genes fail to function properly (due to mutations that affect protein encoding) unregulated cell division and growth can occur and cause development of a tumor.
The body’s natural defense system should detect abnormal cells and destroy them. However tumors may produce substances that obstruct the immune system’s ability to recognize tumor cells; eventually, the tumor cells may overpower all defenses to check their growth.