Gene expression profiles of nonylphenol as representative EDCs in normal human kidney HK-2 cells

Abstract

Nonylphenol (NP) is an organic compound of the wider family of alkylphenols and is a product of industrial synthesis formed during the alkylation process of phenols, particularly in the synthesis of polyethoxylate detergents. NP is an endocrine disruptors. Endocrine-disrupting chemicals (EDCs) are exogenous compounds that have the potential to hamper with hormonal regulations and the normal endocrine system and consequently cause health effects. In numerous chemical substances, the action mechanism of an endocrine disruptor is not clearly understood. In the present study, in vitro gene expression profiles were analyzed in nonylphenol-treated HK-2 cells using an Agilent Human 4 x 44 K whole genome array including 41,000 transcripts. Gene expression profiles were analyzed 3 and 48 hrs after exposure to NP with 2 different doses. We analyzed the gene expression profiles in order to understand the biological effects at level of gene functions and their time-dependent effects. A total of 1,727 genes were identified as being either over or down-expressed over 2-fold changes (P-value < 0.05) in NP treated HK-2 cells. The functional classification of differentially expressed genes showed that cell death related genes were regulated by NP in HK-2 cells. 79 genes were time-dependent and differentially expressed, while 259 genes were concentration-dependent, all of which were selected using an ANOVA method. These data may support the understanding of the toxicity of nonylphenol in normal human kidney cells.