C. albicans activates cyclooxygenase but not its product prostaglandin E2 in HPV 16-stabilized cells

Is Candida albicans a contributor to cancer? A critical review based on the current evidence

The association between Candida albicans (C. albicans) and cancer has been noticed for decades. Whether C. albicans infection is a complication of cancer status or as a contributor to cancer development remains to be discussed. This review systematically summarized the up-to-date knowledge about associations between C. albicans and various types of cancer, and discussed the role of C. albicans in cancer development. Most of the current clinical and animal evidence support the relationship between C. albicans and oral cancer development. However, there is insufficient evidence to demonstrate the role of C. albicans in other types of cancer. Moreover, this review explored the underlying mechanisms for C. albicans promoting cancer. It was hypothesized that C. albicans may promote cancer progression by producing carcinogenic metabolites, inducing chronic inflammation, remodeling immune microenvironment, activating pro-cancer signals, and synergizing with bacteria.

Anti-Candida properties of asaronaldehyde of Acorus gramineus rhizome and three structural isomers

BACKGROUND

Asaronaldehyde (2, 4, 5-trimethoxybeznaldehyde) is an active component of Acorus gramineus rhizome. This study aims to evaluate the anti-Candida efficacy of asaronaldehyde and its three structural isomers, namely, 2, 3, 4-trimethoxybenzaldehyde, 3, 4, 5-trimethoxybenzaldehyde, and 2, 4, 6- trimethoxybenzaldehyde.

METHODS

Susceptibility testing of test compounds was carried out using standard methodology (M27-A2) as per clinical and laboratory standards institute guidelines. Minimum fungicidal concentration (MFC) was determined as the lowest concentration of drug killing 99.9% of Candida cells. The effect on sterol profile was evaluated using the ergosterol quantitation method. Effects on morphogenesis, adhesion and biofilm formation in C. albicans were studied using germ-tube, adherence and biofilm formation assays respectively. Cytotoxicity of test compounds to human RBCs was determined by hemolysis assay.

RESULTS

2, 4, 6-Trimethoxybenzaldehyde exhibited significant anti-Candida activity (P = 0.0412). Minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) were established as 0.25 and 0.5 mg/mL, respectively. All of the test compounds showed significant inhibition of hyphal form transition in yeast at MIC/2 and MIC/4 values. 3, 4, 5-Trimethoxybenzaldehyde and 2, 4, 6-trimethoxybenzaldehyde inhibited adhesion and biofilms. A hemolytic assay of these compounds revealed that they were non-toxic at MIC values. Asaronaldehyde reduced sterol content.

CONCLUSION

Asaronaldehyde and 2, 4, 6-trimethoxybenzaldehyde showed anti-Candida efficacy.

Neisseria gonorrhoeae infection causes DNA damage and affects the expression of p21, p27, and p53 in non-tumor epithelial cells

The constant shedding and renewal of epithelial cells maintain the protection of epithelial barriers. Interference with the processes of host cell-cycle regulation and barrier integrity permits the bacterial pathogen Neisseria gonorrhoeae to effectively colonize and invade epithelial cells. Here, we show that a gonococcal infection causes DNA damage in human non-tumor vaginal VK2/E6E7 cells with an increase of 700 DNA strand breaks per cell per hour as detected by an alkaline DNA unwinding assay. Infected cells exhibited elevated levels of DNA double-strand breaks, as indicated by a more than 50% increase in cells expressing DNA damage-response protein 53BP1-positive foci that co-localized with phosphorylated histone H2AX (γH2AX). Furthermore, infected cells abolished their expression of the tumor protein p53 and induced an increase in the expression of cyclin-dependent kinase inhibitors p21 and p27 to 2.6-fold and 4.2-fold of controls, respectively. As shown by live-cell microscopy, flow cytometry assays, and BrdU incorporation assays, gonococcal infection slowed the host cell-cycle progression mainly by impairing progression through the G2 phase. Our findings show new cellular players that are involved in the control of the human cell cycle during gonococcal infection and the potential of bacteria to cause cellular abnormalities.