ABSTRACT
Candida albicans is the most abundant fungal species in oral cavity. As a smart opportunistic pathogen, it increases the virulence by switching its forms from yeasts to hyphae and becomes the major pathogenic agent for oral candidiasis. However, the overuse of current clinical antifungals and lack of new types of drugs highlight the challenges in the antifungal treatments because of the drug resistance and side effects. Anti-virulence strategy is proved as a practical way to develop new types of anti-infective drugs. Here, seven artemisinins, including artemisinin, dihydroartemisinin, artemisinic acid, dihydroartemisinic acid, artesunate, artemether and arteether, were employed to target at the hyphal development, the most important virulence factor of C. albicans. Artemisinins failed to affect the growth, but significantly inhibited the hyphal development of C. albicans, including the clinical azole resistant isolates, and reduced their damage to oral epithelial cells, while arteether showed the strongest activities. The transcriptome suggested that arteether could affect the energy metabolism of C. albicans. Seven artemisinins were then proved to significantly inhibit the productions of ATP and cAMP, while reduced the hyphal inhibition on RAS1 overexpression strain indicating that artemisinins regulated the Ras1-cAMP-Efg1 pathway to inhibit the hyphal development. Importantly, arteether significantly inhibited the fungal burden and infections with no systemic toxicity in the murine oropharyngeal candidiasis models in vivo caused by both fluconazole sensitive and resistant strains. Our results for the first time indicated that artemisinins can be potential antifungal compounds against C. albicans infections by targeting at its hyphal development.
Subject(s)
Animals , Mice , Candida albicans , Candidiasis, Oral/drug therapy , Antifungal Agents/pharmacology , Hyphae , Artemisinins/pharmacologyABSTRACT
Objective:To evaluate the clinical efficacy of multi-disciplinary single center's CCCG-HB-2016 regimen in the treatment of hepatoblastoma (HB) in children.Methods:Clinical data of 36 HB patients treated with CCCG-HB-2016 program from Aug 2016 to March 2020 were analyzed.Results:These 36 patients included 20 boys and 16 girls. The serum AFP was all higher than 2 792 ng/ml,there was a correlation between AFP and tumor risk stratification ( H=14.973, P<0.05). Twenty eight cases (77.78%) were epithelial type and 8 cases (22.22%) were mixed epithelial mesenchymal type.All children were treated by tumor resection combined with chemotherapy, and there was a correlation between tumor risk stratification and surgical resection of liver lobe ( H=8.847, P<0.05). The probability of bone marrow suppression in the low-risk group was 58.33% (35/60),that in the intermediate-risk group was 73.49% (61/83) and in the high-risk group was 80.23% (69/86).All 36 cases were followed up to March 31, 2020,with an average follow-up of 21.9 months and the median survival was 22.5 months.The overall survival rate (OS) and event-free survival rate (EFS) were 97.2% and 83.3% respectively. Conclusions:The multidisciplinary CCCG-HB-2016 regimen was with a high success rate and along with a high incidence of bone marrow suppression.
ABSTRACT
The hyphal development of Candida albicans (C. albicans) has been considered as an essential virulent factor for host cell damage. However, the missing link between hyphae and virulence of C. albicans is also been discovered. Here, we identified that the null mutants of ERG3 and ERG11, two key genes in ergosterol biosynthesis pathway, can form typical hyphae but failed to cause the oral mucosal infection in vitro and in vivo for the first time. In particular, the erg3Δ/Δ and erg11Δ/Δ strains co-cultured with epithelial cells significantly reduced the adhesion, damage, and cytokine (interleukin-1α (IL-1α)) production, whereas the invasion was not affected in vitro. Importantly, they were incapable of extensive hyphal invasion, formation of micro-abscesses, and tongue epithelium damage compared to wild type due to the decrease of the colonization and epithelial infection area in a murine oropharyngeal candidiasis model. The fluconazole (FLC), an antifungal targeted at ergosterol biosynthesis, relieved the epithelial infection of C. albicansin vitro and in vivo even under non-growth inhibitory dosage confirming the virulent contribution of ergosterol biosynthesis pathway. The erg3Δ/Δ and erg11Δ/Δ strains were cleared by macrophages similar to wild type, whereas their virulence factors including agglutinin-like sequence 1 (Als1), secreted aspartyl proteinase 6 (Sap6), and hyphal wall protein-1 (Hwp1) were significantly reduced indicated that the non-toxicity might not result from the change on immune tolerance but the defective virulence. The incapacity of erg3Δ/Δ and erg11Δ/Δ in epithelial infection highlights the contribution of ergosterol biosynthesis pathway to C. albicans pathogenesis and fluconazole can not only eliminate the fungal pathogens but also reduced their virulence even at low dosage.