The relationship between bacteria and cancer has always been very delicate.
In 1990, scientists discovered the pathogenicity of Helicobacter pylori in gastric cancer for the first time, proving that bacteria may have the ability to prevent cancer cells from "suicide".
In May last year, a study on bacteria inside malignant tumors appeared on the cover of the world's top academic journal "Science", which deepened the academic community's suspicion that bacteria may be "accomplices" of cancer.
As a physiological island, the human body hosts trillions of bacteria and other microorganisms.
Among them, the oral cavity is a hotbed of millions of bacteria, and there are about 700 kinds of resident bacteria.
But where do these bacteria in the mouth come from?
Scientists have discovered that with the improvement of people's living standards, all kinds of food are corroding our teeth, so it is inevitable that we have to put on dentures.
As a "foreign body" in the oral cavity, dentures generally use high-hardness resin materials, which have unique properties such as porosity and water absorption.
Therefore, compared with real teeth, they are easier to contain dirt and become a base for bacteria in the oral cavity.
Not only that, these bacteria in the oral cavity will be silent.
Recently, researchers from the University of Sao Paulo (USP) published an article titled Proto-Oncogenes and Cell Cycle Gene Expression in Normal and Neoplastic Oral Epithelial Cells Stimulated With Soluble Factors From Single and Dual Biofilms in Frontiers in Cellular and Infection Microbiology.
The latest research of Candida albicans and Staphylococcus aureus conducted a series of analyses on the potential link between oral bacteria and head and neck cancer.
Studies have found that fungi and bacteria in the oral cavity not only cause diseases such as periodontitis and dental caries, but also activate the expression of head and neck cancer-related genes.
In recent years, with the in-depth understanding of some chronic and intractable diseases caused by common bacteria in the medical field, it has been discovered that biofilms are the main reason why these bacterial diseases are difficult to cure.
Candida albicans and Staphylococcus aureus are very common in the oral cavity.
According to statistics, these microorganisms can be detected in 30%-40% of subjects, and the metabolites of their biofilms can endanger normal and tumorous oral epithelial cells The steady state.
Therefore, the researchers speculated that it might be possible to use metabolites from the bacterial biofilms of Candida albicans and Staphylococcus aureus to stimulate and attack cells in order to explore the potential connection between bacteria and cancer.
Studies have found that these bacteria in the oral cavity can damage the survival of normal cells and disrupt the cell cycle.
Cell cycle distribution index
In further experiments, the researchers also found that biofilms, as organized growth aggregates of microorganisms, secrete metabolites that can regulate the expression of proto-oncogenes and cell cycle genes related to tumor cell growth and survival, and the gene expression It mainly focuses on the signaling pathways "EGFR/RAS/RAF/MEK/ERK and EGFR/PI3K/AKT/mTOR", which play an important role in the proliferation, differentiation and survival of tumor cells.
The expression of proto-oncogenes and cell cycle genes of soluble factors in biofilms
All in all, this research lays the foundation for metabolomics and proteomics studies of oral biofilms.
In the future, researchers will focus on the prevalence of Candida albicans and Staphylococcus aureus biofilms in the dentures and oral cavity of patients with head and neck cancer.
In-depth exploration will bring more new ideas or methods for cancer diagnosis and precision treatment.
Currently, this research has been supported by the Sao Paulo Research Foundation (FAPESP) and the National Council for the Development of Science and Technology (CNPq).
Not only that, the project also received funding from the Colombian COLCIENCIAS and SAPIENCIA institutions, and established partnerships with the Araraquara School of Dentistry (FOAr) and the Araraquara School of Pharmacy (FCFAr) of the University of São Paulo.