2.12. In vivo tumor formation model

MG-63 cells (5 × 10⁶) stably transfected with sh-BAIAP2L2 or LV-NC (control) were subcutaneously injected into BALB/c nude mice (4–6 weeks old) at day 0 (n = 6 for each group, male and female was equally distributed in each group), housed under SPF conditions (temperature was 22 ℃, illumination time was 12 h, humidity was 45%). All animal experiments were performed under the institutional guidelines approved by the Use Committee for Animal Care. Before harvesting the tumors, mice were euthanized with isoflurane set at saturated vapor pressure. This study was approved by the Ethics Committee of Animal Use of the University Three Gorges Hospital. Mice were euthanized at 28 d, heart completely stopped and the dilation of pupil was used to judge the end point. Tumors were then excised and measured.