Search Results (4)

Cancer immunobiology is one of the hot topics of discussion amongst researchers today, and immunotherapeutic modalities are among the selected few emerging approaches to cancer treatment that have exhibited a promising outlook. However, immunotherapy is not a new kid on the block; it has been around for centuries. The origin of cancer immunotherapy in modern medicine can be traced back to the initial reports of spontaneous regression of malignant tumors in some patients following an acute febrile infection, at the turn of the twentieth century. This review briefly revisits the historical accounts of immunotherapy, highlighting some of the significant developments in the field of cancer immunobiology, that have been instrumental in bringing back the immunotherapeutic approaches to the forefront of cancer research. Some of the topics covered are: Coley’s toxin—the first immunotherapeutic; the genesis of the theory of immune surveillance; the discovery of T lymphocytes and dendritic cells and their roles; the role of tumor antigens; relevance of tumor microenvironment; the anti-tumor (therapeutic) ability of Bacillus Calmette– Guérin; Melacine—the first therapeutic vaccine engineered; theories of immunoediting and immunophenotyping of cancer; and Provenge—the first FDA-approved therapeutic vaccine. In this review, head and neck cancer has been taken as the reference tumor for narrating the progression of cancer immunobiology, particularly for highlighting the advent of immunotherapeutic agents. Full article

Oncolytic bacteria are a classification of bacteria with a natural ability to specifically target solid tumors and, in the process, stimulate a potent immune response. Currently, these include species of Klebsiella, Listeria, Mycobacteria, Streptococcus/Serratia (Coley’s Toxin), Proteus, Salmonella, and Clostridium. Advancements in techniques and methodology, including genetic engineering, create opportunities to “hijack” typical host–pathogen interactions and subsequently harness oncolytic capacities. Engineering, sometimes termed “domestication”, of oncolytic bacterial species is especially beneficial when solid tumors are inaccessible or metastasize early in development. This review examines reported oncolytic bacteria–host immune interactions and details the known mechanisms of these interactions to the protein level. A synopsis of the presented membrane surface molecules that elicit particularly promising oncolytic capacities is paired with the stimulated localized and systemic immunogenic effects. In addition, oncolytic bacterial progression toward clinical translation through engineering efforts are discussed, with thorough attention given to strains that have accomplished Phase III clinical trial initiation. In addition to therapeutic mitigation after the tumor has formed, some bacterial species, referred to as “prophylactic”, may even be able to prevent or “derail” tumor formation through anti-inflammatory capabilities. These promising species and their particularly favorable characteristics are summarized as well. A complete understanding of the bacteria–host interaction will likely be necessary to assess anti-cancer capacities and unlock the full cancer therapeutic potential of oncolytic bacteria. Full article

The ability of the immune system to precisely target and eliminate aberrant or infected cells has long been studied in the field of infectious diseases. Attempts to define and exploit these potent immunological processes in the fight against cancer has been a longstanding effort dating back over 100 years to when Dr. William Coley purposefully infected cancer patients with a cocktail of heat-killed bacteria to stimulate anti-cancer immune processes. Although the field of cancer immunotherapy has been dotted with skepticism at times, the success of immune checkpoint inhibitors and recent FDA approvals of autologous cell therapies have pivoted immunotherapy to center stage as one of the most promising strategies to treat cancer. This review aims to summarize historic milestones throughout the field of cancer immunotherapy as well as highlight current and promising immunotherapies in development. Full article