Exploration of self assembled multifunctional nanocarriers for the delivery of anticancer agents

Abstract

Cancer is the leading cause of human death worldwide, despite tremendous attempts over several decades to fight cancer with consistent growth in diagnostic and therapeutic approaches. The latest database of GLOBOCAN 2018 estimated that 18.1 million fresh instances and 9,6 million fatalities from cancer globally were reported in 2018, increasing by 2040 up to 29.4 million. The report also estimated that one out of five men and one out of six women worldwide would develop cancer during their lifetime, and one out of eight men and one out of eleven women would die from cancer. These facts emphasize the vital need for continued innovation in research and the development of new and more powerful therapeutic strategies to address the threat of cancer. It is of paramount importance to have a comprehensive idea of cancer to develop new therapeutic targets and tools (Kawasaki and Player 2005, Wild 2019). According to India 2018 cancer statistics, approximately 2.25 million people were reported to be living with cancer. Over 11,57,294 new cancer victims are recorded each year, and a total of 7,84,821 cancer-related fatalities. The most prominent cancers are of breast, cervical, oral, stomach and lung, which are among India's top five cancers. 47.2 % of all cancers are these top five cancers. If cancer can be prevented, screened for or detected at an early stage, the death rate from these cancers can be significantly reduced (Figure 1.1) (Bray, Ferlay et al. 2018). 1.1. Cancer: Overview Cancer is a generic term for a very complex multifaceted disease in which a set of abnormal cells displays uncontrolled proliferation, invasion, and sometimes metastasis, and thus hinders the normal functioning of the body (Cao, DePinho et al. 2011). Continuous cell growth often leads to the formation of tumors which are sub-classified as benign and malignant tumors. Benign tumors such as skin warts remain confined to their initial location, while metastatic tumors have the property to spread and invade surrounding tissues (Chak, Canto et al. 1997). The main reason for cancer is the genetic abnormalities in cells caused by DNA mutations of normal cells that make them carcinogenic. Mutations are primarily caused by exposure to carcinogens such as tobacco smoke, chemicals, radiation or infectious agents. Cancer is commonly divided into five classes according to their mother tissue, carcinomas, sarcomas, leukemias, lymphomas, and central nervous system cancer. Carcinomas refer to malignancies that originate in the skin or in tissues that line or wrap internal organs, usually epithelial cells. It is the most common type and accounts for 90% of human cancers. Sarcomas is a tumor of bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemias are usually caused by blood-forming tissue such as the bone marrow, which leads to the production of abnormal blood cell count. Lymphomas are cancer that occurs in the cells of the immune system. Cancers that begin in the brain and spinal cord tissues are referred to as central nervous system cancer (Cooper, Hausman et al. 2000).