Scid mice

ICR mice used for isolation of MEFs and severe combined immunodeficient (SCID) mice used for teratoma formation were purchased from Japan SLC (Shizuoka, Japan), Shimizu Laboratory Supplies (Kyoto, Japan), and CLEA Japan (Shizuoka, Japan). Prior publications have detailed the generation and establishment of ScxGFP Tg mice (Sugimoto et al., 2013b (link)). The mice were housed in a temperature-controlled animal facility with a 12-hour light cycle. All mouse experiments were performed in accordance with relevant guidelines and regulations. All animal experimental procedures were approved by the Committee of Animal Experimentation, Hiroshima University, and the Animal Care and Use Committee of the Tokyo Metropolitan Geriatric Hospital and Institute of Gerontology.

Female BALB/c nude and SCID mice (4-weeks old) were obtained from Japan SLC, Inc., Shizuoka, Japan. All animal protocols used in this study were approved by the Institutional Animal Care and Use Committee at Dongnam Institute of Radiological & Medical Sciences (DIRAMS; Busan, Republic of Korea). SCID mice (n=10) were randomly divided into two groups and each mouse were transplanted with NS or shM1 LD611 cells and killed 30 days post injection. Total number of 32 nude mice were randomly divided into four groups (NS, shM1 #1, shM1 #2 and #1+M1; n=8 for each group) and each cell line (1 × 10⁶) was inoculated subcutaneously into nude mice. For testing the effect of Lin28B knockdown on tumor formation, nude mice (n=10 for each group) were injected with NS or shLin28B LD611 cells (1 × 10⁶). In case of Lin28B overexpression test, Mock or Lin28B-overexpressing LD611 cells (1 × 10⁶) were inoculated into nude mice (n=5 for each group). Tumor volume was estimated as follows: tumor volume=(short axis)² × (long axis) × 0.5. All animal studies were followed by a blind randomized animal study protocol.