LMW-E is tumorigenic.

Athymic mice were injected subcutaneously with 1×107 76NE6 cells stably transfected with empty vector, EL, LMW-E and MDA-MB-468 cells. After 10 weeks, the tumors were removed for expansion in culture for further in vivo passaging and also for IHC analysis. Tumor incidence rate was estimated with exact 95% confidence intervals and Fisher's exact tests were used to compare tumor incidence rate between/among groups (*p<0.0001: 76NE6-vector vs. 76NE6-LMW-E; 76NE6-EL vs. 76NE6-LMW-E; 76NE6-vector vs. TDCs; 76NE6-EL vs. TDCs).

将1×10⁷个分别经空载体、EL、LMW-E稳定转染的76NE6细胞，以及MDA-MB-468细胞皮下注射至无胸腺裸鼠（athymic mice）体内。造模10周后，剥离肿瘤组织，一部分用于体外培养扩增以开展后续体内传代实验，另一部分用于免疫组织化学（Immunohistochemistry，IHC）分析。采用精确95%置信区间估算肿瘤发生率，通过费希尔精确检验比较各组间的肿瘤发生率（*p<0.0001：76NE6-vector组 vs. 76NE6-LMW-E组；76NE6-EL组 vs. 76NE6-LMW-E组；76NE6-vector组 vs. TDCs组；76NE6-EL组 vs. TDCs组）。