Current Strategies to Enhance Anti-Tumour Immunity

Abstract

The interaction of the immune system with cancer is complex, but new approaches are resulting in exciting therapeutic benefits. In order to enhance the immune response to cancer, immune therapies seek to either induce high avidity immune responses to tumour specific antigens or to convert the tumour to a more pro-inflammatory microenvironment. Strategies, including vaccination, oncolytic viruses, and adoptive cell transfer all seek to induce anti-tumour immunity. To overcome the suppressive tumour microenvironment checkpoint inhibitors and modulators of regulatory cell populations have been investigated. This review summarizes the recent advances in immune therapies and discusses the importance of combination therapies in the treatment of cancers.

Understanding the Immune-Stroma Microenvironment in B Cell Malignancies for Effective Immunotherapy

“…On the other side, tumor-targeting drugs can have indirect effects on the TME that may boost clinical responses. In CLL, there is evidence that ibrutinib treatment alleviates T cell exhaustion ( 277 ), while chemotherapy-induced cancer cell death promotes the exposure of tumor neoantigens and could re-invigorate anti-tumor immune responses ( 278 ). Understanding how the TME is shaped by currently available treatments can help to understand resistance mechanisms and to design combination therapies to boost clinical responses.…”

Semaphorin Signaling in Cancer-Associated Inflammation

“…In addition, a subset of T regulatory lymphocytes (Treg) can suppress the function of T cytotoxic and T helper cells, the presence of which is instead associated with better prognosis. In fact, therapeutic strategies such as immune checkpoint blockade and immunomodulatory molecules seek to counteract the activity of suppressor cells and promote anti-tumor immune response [9].…”

Enhancing the efficacy of immunotherapy using radiotherapy

“…3 'Hot' tumors, on the other hand, are characterised by high concentrations of tumorinfiltrating immune cells, particularly CD3 + CD8 + T cells at the tumor centre and invasive margin. 4,5 Accumulating data from preclinical studies suggests that radiotherapy can convert 'cold' tumors to 'hot' tumorsparticularly through enhancing antigen visibility to dendritic cells (DCs). This 'licenses' DCs to present tumor antigens to na€ ıve CD4 + T cells, or cross-present to na€ ıve CD8 + T cells, triggering cytokine and chemokine release plus activation and infiltration of tumor-specific T cells to the tumor bed to target cancer cells.…”

“…On the one hand, a cold tumor is characterised by low or absent levels of tumor‐specific antigen, defective recruitment of antigen‐presenting cells (APCs), lack of co‐stimulation, and few infiltrating cytotoxic T cells 3 . ‘Hot’ tumors, on the other hand, are characterised by high concentrations of tumor‐infiltrating immune cells, particularly CD3 + CD8 + T cells at the tumor centre and invasive margin 4,5 . Accumulating data from preclinical studies suggests that radiotherapy can convert ‘cold’ tumors to ‘hot’ tumors – particularly through enhancing antigen visibility to dendritic cells (DCs).…”