The Interaction of Immune System in Tumour Microenvironment and Possible Role of Cancer Cell Immnunosensitization for Better Treatment Efficacy: A Review

Unlike haematologic malignant cells which express cell surface common antigens uniformly and are susceptible to targeted cancer immunotherapy, solid tumours either lack such antigens or have been mutated due to chemotherapy or other therapeutic interventions. Moreover, rapidly dividing tumour cells present complex and dynamic tumour metabolism, which hampers immune cells' reactivity against the tumour cells. Hence solid tumours other than immune-sensitive cancers such as melanoma and renal cell carcinoma are less responsive towards current cellular immunotherapy strategies, including cytokine therapy, dendritic cell-based vaccines, and immune-activating antibodies. Nonetheless, emerging evidence supports combined approaches that target immunosuppressive or antiapoptotic molecules, involving sensitization of the cancer cells by immunosensitizing drugs to express specific ligands that will be recognized by the immune cells via trafficking. This review highlights the immune system's involvement in the tumour microenvironment and the potential significance of cancer cell immunosensitization for improved treatment outcomes.