Relationship Between The Expression Of Genes Encoding Transcription Factors And Fluconazole Resistance In Candida Albicans

[Objective] Candida albicans were collected and identified from clinical specimens, to investigate the susceptibility to fluconazole in vitro. Fluconazole-resistant and-susceptible C. albicans isolates were collected, and were detected the relationship between fluconazole resistance and expression of C. albicans genes encoding transcription factors UPC2,TAC1,MRR1and drug resistance-related genes CDR1,CDR2,MDR1,FLU1, ERG11. In order to better understand the relationship between genes encoding transcription factors and resistance to azoles.[Methods] C. albicans were collected from clinical specimens and were identified by germ tube formation test, CHROMagar medium, and chlamydospore formation test. M27-A2Broth microdilution method was used to assess the susceptibility of clinical C. albicans to fluconazole. The total RNA was extracted from fluconazole-resistant and-susceptible C. albicans isolates and cDNA was synthesized. The expression of drug resistance-related genes was then detected by quantitative real-time PCR.[Results] Totally,379clinical isolates of C. albicans were collected. Sensitivity rate of C. albicans to fluconazole is98.68%(374/379), dose dependent sensitivity rate is0.00%(0/379), and resistant rate is1.32%(5/379). Higher expression of UPC2/CDR2gene was observed in the fluconazole-resistant isolates than that in the fluconazole-susceptible isolates.However,the expression of TAC1/MRR1was no statistical difference. The expression of UPC2/CDR2gene in the fluconazole-resistant isolates was7.22,2.45times as much as that in the fluconazole-susceptible isolates respectively.[Conclusion] Most of C. albicans isolates are susceptible to fluconazole. Fluconazole still can be used to treat clinical C. albicans infections. It is likely that the over-expression of UPC2and CDR2gene is relevant to fluconazole resistance in C. albicans. The higher expression of resistance genes may lead to drug resistance in C. albicans. The function of Zinc cluster transcription fators in drug resitance needs to be further studied.But not all fluconazole-resistant isolates can appear higher expression of above mentitioned genes in the meantime. Multiple molecular mechanisms lead to the resistance to azoles in C. albicans, so in the future further explore should be done to beter understand molecular mechanisms of resistance to azoles.