Results from our study show for the first time that HIV-1 Tat upregulated AEG-1 expression via the PI3-k signaling pathway, and that upregulated AEG-1 induced YY-1 expression via the NF-κB signaling pathway, thereby inhibiting EAAT-2 expression during HAND. The gene discussed is YY1; the disease is HIV-associated neurocognitive disorder.