In other primary human NPC cells, pNPC-2, pNPC-3, and pNPC-4, stable Gαi1 knockdown by Gαi1-shRNA-s2-expressing lentivirus (see Fig. 3) also provoked Caspase-3 activation (Fig. 4F) and increased the number of nuclei with positive TUNEL staining (Fig. 4G). Here, CASP3 is linked to nasopharyngeal carcinoma.