The Gacser group is specialized in the investigation of infectious diseases caused by opportunistic pathogenic species. The group approaches infectious disease research from various aspects. One includes the pathogen’s perspective, where major questions such as ‘What makes a fungal pathogen actually a pathogen?” are addressed. Another aspect of the investigations includes the examining of host defense mechanisms where innate and adaptive immune responses are monitored during the infection. Recently, the group launched another approach to study infectious diseases, that aims to examine “How do opportunistic yeast infections might contribute to an underlying disease’s progression?”. The majority of running projects in the HCEMM program focus on addressing the latter aspect. 

To address the question how might pathogenic fungi contribute to disease progression, Candida species are applied as a pathogen model, while oral squamous cell carcinoma (OSCC) cells are used to represent the host. Previously, our group has shown that the likeliness of oral candidiasis development is significantly higher in oral tumor patients

compared to healthy individuals, and the well-known white patches are more likely to develop on neoplastic surfaces rather than on non-tumoric areas of the oral cavity of cancer patients. In the meantime, other groups proposed the possibility that certain fungal species may possess potentially tumor progression promoting factors. Recently, our group revealed that the presence of an opportunistic pathogenic Candida species, Candida albicans, contributes to OSCC progression via several mechanisms, such as triggering elevated matrix metalloprotease secretion, elevating the expression of OSCC-progression oncogenes, and increasing the migration capabilities of OSCC cells, thereby providing a direct evidence for fungi-driven tumor progression events for the first time. 

Based on these observations, our group aims to reveal what lies behind the observed phenomena, and to identify 1) what fungal elements trigger such a progressive response, 2) what are the potentially altered mechanisms that occur in tumor cells and 3) how either of these fluctuate during tumor-pathogen interactions. 

Based on these aims, the following projects are in progress:

1. Investigating the role of extracellular vesicle (EV)-based communication between tumors and pathogens

2. Exploring the role of potentially altered OSCC-progression indicatory signaling pathways following fungal stimuli and identification of key targetable elements

3. Identifying potentially underlying signal transduction regulatory mechanisms that aid tumor progression during infection