The Microbiome of Oesophageal Squamous Cell Carcinoma

Oesophageal carcinoma significantly contributes to the global cancer burden ranking as the sixth leading cause of global cancer-related death. Oesophageal squamous cell carcinoma (OESCC) is one of the most common type of upper gastrointestinal (UGI) carcinoma in some regions globally, particularly China and Japan in Asia. The disease has an extremely poor prognosis, with overall 5-year survival rates of less than 30%, mainly due to late stage at diagnosis and high likelihood of distant metastases. Although OESCC is associated with risk factors including smoking and alcohol, the aetiology of OESCC is still poorly understood.

Increasing evidence indicates a key role for bacterial microbiota in carcinogenesis. Emerging data implicates the human microbiome in a variety of cancers, most notably Fusobacterium in colorectal cancer and Helicobacter in gastric cancer. The consortium of bacterial microbiome colonizing the gastrointestinal tract is extensive and interact in a complex manner. The microbiome may interact with genetic and environmental factors to metabolize dietary constituents and xenobiotics, among other functions. When the microbial balance is disturbed, the microbiota could alter host cell proliferation and death, manipulate the immune system, and influence host metabolism, giving rise to carcinoma. Several studies have reported an important role of the human microbiota in upper gastrointestinal carcinoma and found associations between the microbiota and some diseases of the UGI tract, such as esophagitis and Barrett esophagus, and with squamous dysplasia and squamous carcinoma of the oesophagus. Another even less well known is the role of the fungal microbiome in OESCC.

Here the investigators will seek to evaluate the role of the bacterial and fungal microbiome in OESCC and the host microbe interactions that may play a role in the understanding and management of OESCC.

Study questions:

1. Does the microbiome differ between OESCC and normal patients?
2. Does the microbiome change from normal through premalignancy to malignancy?
3. What are the mechanisms involved in the microbiome and the development or progression of OESCC?