The 5-amino-3-methyl-4-isoxazolecarboxylic acid hydrazide (HIX) is a synthetic isoxazole derivative with a potential for development as an anti-inflammatory drug candidate. The goal of this study was to explore in vitro autoimmune and inflammatory gene modulation by HIX in human Caco-2 cultured cells. The effect of low dose of HIX was tested on the expression level of RNA in 24 h Caco-2 cultures using the QIAGEN Th17 for Autoimmunity & Inflammation RT2 Profiler PCR Array. We choose the PCR technology as the most reliable and sensitive gene expression profiling method for analyzing specific gene regulatory networks. In all experiments, Leflunomide (5-methyl-N-[4-(trifluoromethyl)phenyl]-4-isoxazolecarboxamide), an immuno-suppressive disease-modifying antirheumatic drug was used, as a reference to clinical utility of the isoxazole derivatives. Changes in RNA levels were analyzed and differentially expressed genes with at least 2-fold change were identified. For the majority of genes tested, the effe...