CASP3 and astrocytoma (excluding glioblastoma): Our results reveal that HIV-1 gp120 clade C treated astrocytoma induced the expression of key ER stress mediated apoptosis markers, such as the activating transcription factor 4 (ATF4), caspase 3 (CASP3) and CCAAT-enhancer-binding protein homologous protein (CHOP), also known as growth arrest and DNA damage-inducible gene 153 (GADD153).