Brasilia [Brazil], May 26 (ANI): A research group at Sao Paulo State University (UNESP) has analyzed how Candida albicans fungi and Staphylococcus aureus bacteria influence gene expression and tumour cell survival.
An in vitro study conducted by researchers at UNESP in Araraquara, Brazil, shows how fungi and bacteria can activate genes associated with head and neck tumours, as the metabolism of biofilms (communities in which these microorganisms self-organize in a structured and coordinated manner) stimulate tumour cells by favouring the cell signalling pathways required for tumour development and resistance to treatment.
The findings include entirely novel information on the links between microbial biofilms and cell behaviour in head and neck cancer.
The researchers discovered that metabolites secreted by biofilms termed the secretome, can modulate the expression of proto-oncogenes and cell cycle genes associated with tumour cell growth and survival.
Their analysis of gene expression focused on two signalling pathways (EGFR/RAS/RAF/MEK/ERK and EGFR/PI3K/AKT/mTOR) that play a key role in tumour cell proliferation, differentiation, and survival. Alterations to gene expression in these pathways are highly prevalent in various types of tumour.
The researchers analyzed head and neck and oral cavity squamous carcinoma cells. Squamous cell carcinoma is the most common type of mouth cancer, which produces functional and aesthetic changes that degrade the patient's quality of life.
The cells were challenged via stimulation by metabolites from biofilms of Candida albicans fungi and Staphylococcus aureus bacteria. These microorganisms are very frequent in users of dentures: prior research found both in 30 per cent-40 per cent of subjects examined.
Oral microbiota is known to play an important role in the development of cancer. Genetic markers associated with the presence of microorganisms have been identified for some types, such as stomach cancer, but there is no consensus regarding the most prevalent genes linked to head and neck cancer, and no molecular markers had hitherto been found for this disease, especially HPV-negative cancer, which has a worse prognosis.