Colorectal cancer (CRC) and hepatocellular carcinoma (HCC) are two of the most prevalent and deadliest types of gastrointestinal cancer. A risk factor common for CRC and HCC is intestinal inflammation induced by pathological changes in the composition of gut microbiota. Professor Jia Wei, Cheung On Tak Endowed Professor in Chinese Medicine from the Teaching and Research Division, and his team have recently published a review in the scientific journal Protein & Cell (https://link.springer.com/article/10.1007/s13238-020-00748-0), summarising distinct changes in the composition of the gut microbiota at different stages of CRC and HCC.
Based on the view that the gut microbiota are an additional “lifeline” for cancer and contribute to the tumor microenvironment (TME), it has been observed in some published literature how the microbiota can cause a shift in balance (normal → inflammation → reduced inflammation) from early to later disease stages. This pattern of change has given rise to the hypothesis that tumor survival depends on a less pro-inflammatory TME. The article also analyses and compares the gut microbiota of CRC and HCC with different causes and finds that there were many more bacteria genera reported in gut microbiota shifts for CRC than for HCC. The changes in gut microbiota of viral and non-viral HCC were significantly different.
Professor Jia believes that the gut microbiota do contribute to the modelling of TME via providing nutrients or immune modulation. By manipulating the microbiota to treat CRC and HCC, one can expect to achieve in theory similar effect as that of denying blood supply to starve the tumor.
Professor Jia Wei