Expression profile of genes associated with biofilm formation in Candida spp. isolates from patients with recurrent vulvovaginal candidiasis

The virulence of Candida spp. has been associated with the development of recurrent vulvovaginal candidiasis (RVVC). Among these virulence factors, biofilms represent a mechanism for fungal persistence in tissues, which could explain the recurrence of this condition. This study evaluated the expression profile of genes related to biofilm formation in Candida spp. isolates from patients with RVVC. These isolates were divided into two groups: 26 isolates from patients with ≤ seven episodes of VVC and 11 isolates from patients with ≥ eight episodes of VVC, each over a period of one year. The expression of the genes ALS1, ALS3, BCR1, HWP1, EFG1, TEC1, ROB1, UME6, NRG1, ACE2, PGA10 , and ACT1 was evaluated in both planktonic cells and their biofilm form using qPCR. A significant increase in the expression of genes associated with the adhesion phase ( ALS1 and PGA10 ) and the dispersion phase (UME6) was observed in planktonic cells. In biofilm cells, increased expression of the ROB1 and BCR1 genes and decreased expression of the ACE2 gene were observed. Interestingly, the changes in expression were more significant in isolates from patients with more than eight episodes of VVC per year. These results suggest that the expression of genes related to biofilm formation is one of the most important virulence mechanisms of Candida spp. and appears to be associated with the number of VVC ​​recurrences.