Cancer is one of the deadliest and dreadful diseases leading to a massive increase in the mortality rates every year. Any abnormal proliferation of cells that invades the adjacent tissues and causes the destruction of these tissues can lead to cancer. Two classes of genes play a crucial role in this malignant transformation of normal cells—oncogenes and tumor suppressor genes. Any dysregulation in these genes due to genetic alterations can lead to cellular transformation. Though it is often impossible to evaluate the specific cause for specific cancer, there are certain factors known to increase the risk of cancer such as tobacco use, alcohol, environmental pollutant, infectious agents, custom habits and sedentary lifestyles.