Title:Immune Checkpoint Regulators: A New Era Toward Promising Cancer Therapy
Volume: 20
Issue: 6
Author(s): Mohammed Shaaban, Heba Othman, Takwa Ibrahim, Mariam Ali, Mohamed Abdelmoaty, Abdel-Rahman Abdel-Kawi, Ahmed Mostafa, Aya El Nakeeb, Heba Emam and Alaa Refaat*
Affiliation:
- Scientific Research Center, MISR International University, Cairo,Egypt
Keywords:
Cancer immunotherapy, checkpoint stimulators, checkpoint inhibitors, immuno-surveillance, tumor microenvironment,
PD-1, CTLA-4, SIRPα/CD47.
Abstract: During the last century, our battle against cancer has been inaugurated upon three main
approaches; surgery, radiation and chemotherapy. The latest findings on the effectiveness of immunotherapy
in cancer management offer a ray of hope after decades of research and studies on the best
treatment methods. Immunotherapy has proven effective in the surveillance and destruction of cancer-
causing cells, demonstrating its ability to suppress cancer through controlling the wellestablished
immune-editing process. Immuno-editing is a process that comprises three principal elements;
elimination, equilibrium, and escape, and is paramount to the comprehension of checkpoint
inhibition. Cancer cells employ various approaches to evade the elimination step leading to its immune-
escape. The escape mechanism encompasses the up-regulation of negative co-signals that
block successful activation of cancer-eradicating immune cells, developing cytokine background that
favors the immunosuppressive tumor microenvironment (TME), or dropping the expression of tumor-
specific proteins known as neo-antigens, therefore reducing the immunogenic activity against
cancer cells. Today, checkpoint inhibitors are considered as a primary approach in our fight against
cancer. Strategies targeting the inhibitory roles of checkpoint inhibitors have been shown effective
against different cancer types and stages, and some already gained the FDA’s approval. This review
seeks to comprehensively cover the historical background as well as the most recent updates for the
role of immune checkpoint regulators in the maintenance of immune homeostatic balance as well as
keeping the tumorigenic cells in check.
