Current Immunotherapy Techniques for Cancer Treatment: A Scoping Review

Abstract

Introduction: Immunotherapy, or the utilization of the immune system in fighting cancer, has been of interest as of late. Many different immunotherapy strategies exist, such as modifying T cells, generating cancer vaccines, as well as using chemokines, to elicit a strong anti-tumor response. As a strong emerging field in cancer research, this paper aims to conduct a scoping review to investigate the current research in immunotherapy targeting cancer and to summarize popular methods versus under-researched topics in the field. 

Methods: This scoping review follows PRISMA. Articles were found using MEDLINE, Scopus, and EMBASE, and were then screened using inclusion and exclusion criteria using the title and abstracts and then the full text. After the screening stage, papers chosen were categorized depending upon the authors’ main method of adapting the immune system to target cancer. 

Results: A total of 194 articles were included in this review. From the 194 articles, the method with the greatest amount of research in adapting the immune system to attack cancer are CAR-T cells, with 31 articles (16.0%). The second greatest category was cancer vaccines (28 articles; 14.4%), the third largest was other T cell-based immunotherapy strategies (25 articles; 12.9%) and the fourth largest was generating antibodies (24 articles; 12.4%). Other notable categories include cytokines and immune checkpoint inhibitors, while the smallest categories include bacteria, natural medicine, and nanoparticles.

Discussion: The main fields of CAR-T cells, cancer vaccines, and antibodies commonly target tumor antigens involved in either tumor proliferation and progression or cancer invasion and metastasis. Further research is needed to demonstrate the strengths or limitations of using one immunotherapy technique over the other when it comes to inhibiting both of these cancer hallmarks. Furthermore, the review identifies multiple promising future avenues of immunotherapy that are currently less extensively investigated, such as adapting other immune cells, coupling immunotherapy techniques with nanoparticles, or using bacteria proteins to elicit a stronger immune response. 

Conclusion: This review aids in summarizing current focuses in the field of immunotherapy and provides future avenues and next steps for cancer research for new scientists pursuing a career in cancer research.