Microbiome and cancer treatment: Are we ready to apply in clinics?

Cancer treatment has been evolving in recent decades from surgery, conventional chemotherapy and radiation therapy to targeted therapies and more recently immunotherapies. Despite significant improvement in the efficacy of treatment with the discovery of novel therapies targeting particular cancer-related gene and proteins and more recently the immune system-modulating biologics, still only patients with specific subtypes of cancer benefit from those targeted therapies and there is room for further improvement of survival outcomes. As failure of cancer treatment is not uncommon in clinical practice, a lot of biomarker studies have been carried out with an aim to identify factors contributing to disease relapse and treatment failure. Gut microbiome is one of the research areas which warrants further investigation of its impact on cancer treatment as microbiota has long been proven to profoundly shape mammalian immunity. As there is increasing evidence showing a strong association between gut microbiota and clinical outcomes of immunotherapy, modulation of intestinal micro-ecological system may be a possible strategy to help improve therapeutic impact of immunotherapy in oncology practice.