Unravelling Drug Resistance in Candida Species: Genetic, Biofilm, Transcriptional, and Epigenetic Perspectives

Candida species infections pose a substantial threat in the realm of human-induced fungal diseases, particularly impacting immunocompromised individuals. While various Candida species contribute to systemic candidiasis, the existing antifungal arsenal remains limited, and resistance is on the rise. However, the emergence of drug resistance, particularly in non-albican species, poses a grave threat to current therapeutic approaches. This phenomenon involves primary, acquired, and clinical resistance, influenced by various factors like host immunity, pharmacokinetics, and fungal pathobiology. Genetic alterations play a central role, affecting key genes encoding enzymes vital for antifungal susceptibility. Biofilms present a significant challenge to antifungal treatments, acting as a shield and hindering drug impact. The complex biofilm structure, including filamentous hyphae, pseudo-hyphae, blastospores, persister cells, and extracellular matrix components, collectively contributes to Candida’s resilience and survival. Efflux transporters, mainly ABC and MFS groups, actively expel intracellular drugs, playing a crucial role in drug resistance. The comprehensive understanding of genetic variations, biofilm dynamics, transcriptional regulation, and epigenetic modifications collectively contributes to drug resistance, impacting antifungal efficacy and patient outcomes. This chapter discusses the multifaceted nature of Candida drug resistance, covering genetic alterations, drug efflux pumps, biofilm intricacies, transcriptional regulations, and epigenetic modifications. Addressing these complexities requires innovative solutions and therapeutic targets, exploring synergies, and enhancing treatment outcomes. The unravelling Candida drug resistance mechanisms holds promise for developing precise interventions and improving antifungal strategies to combat these challenging infections effectively.