Altered expression of mRNA for HIF-1alpha and its target genes RTP801 and VEGF in patients with oral lichen planus.

OBJECTIVE: To explore a potential causal contribution of the transcription factor HIF-1alpha and its target gene, RTP801 and VEGF, to the development of oral lichen planus (OLP). Design relevant: Twenty-two adult OLP patients were enrolled in this study. All OLP diagnoses were verified by histopathological characteristics. Normal mucous specimens were collected from 12 controls after various oral surgeries.

MATERIAL AND METHOD: RNA was isolated from OLP and control specimens. Microarray was performed using BiostarH-40s gene chip. Expression of HIF-1alpha, VEGF and RTP801 was evaluated using quantitative real-time polymerase chain reaction (qPCR). Unpaired t-test and one-way ANOVA was used for statistical analysis.

RESULTS: Microarray results showed that RTP801 expression was lower in OLP than in controls (779 vs 3090). qPCR further confirmed that expression of RTP801 was similarly lower in OLP than in controls (0.363 vs 1.473, P < 0.001); expression of VEGF was also lower in OLP (0.448 vs 1.74, P = 0.012). In contrast, expression of HIF-1alpha was higher in OLP than in controls (11.12 vs 1.628, P < 0.001).

CONCLUSION: The oral mucosa of OLP is hypoxic. Genes that are activated by hypoxia, such as RTP801 and VEGF, and their signal cascades may be novel potential therapeutic targets for OLP.