Photodynamic therapy using sulfonated aluminium phthalocyaninemix for the eradication of cervical cancer and cervical cancer stem cells

Abstract: Treatment of many cancers including carcinoma of the cervix has been problematic although, scientists across the globe are trying to find new ways of combating the hurdles in cancer treatment. Cervical cancer is a very common gynecologic malignancy worldwide and especially in developing countries, it is the leading cause of cancer related deaths among women, with approximately half of a million cases diagnosed each year (WHO, 2014, Ferlay et al., 2010). It is, a malignant neoplasm that is initiated by transformation of the basal layer cells of the cervix upon infection with the Human Papillomavirus, HPV and progressively spreads through the entire thickness of the cervix uteri. Current treatments including surgery, chemotherapy and radiation, administered separately or combined have shown limited therapeutic potential with severe associated side effects, poor prognosis, high rates of cancer recurrence and reduced quality of life (Lee et al., 2016). With intensive focus on the study of tumor biology and immunology in recent years, numerous studies have reported the presence of a subpopulation of cells in cancer that is distinct from the cells of the entire tumor. These cells possess stem cell properties and have been associated with tumor generation, metastasis and resistance to therapy. Referred to as cancer initiating cells or more commonly, cancer stem cells (CSCs), these cells have been isolated from many tumors including cervical cancer and their role in tumor biology and treatment resistance has been well characterized. The high incidence of tumor relapse after conventional chemotherapy in cervical cancer has implicated CSCs as the main cause. CSCs have also shown a high treatment resistance to both chemo and radiation therapy (Holohan et al., 2013). CSCs have the highest potential to escape damage by cytotoxic and genotoxic drugs because of their inherent properties of enhanced DNA repair mechanisms, characteristics of their stem cell niche, and the ability to efflux (pump out) drugs out of the cell. Due to these...M.Tech. (Biomedical Technology