Fig. 7.

Knockdown of LAMA4 suppresses the malignant behaviour of osteosarcoma and accelerates ER stress-induced apoptosis. A The expression levels of LAMA4 in osteosarcoma (n = 88) and normal tissues (n = 564) were analysed from the TNMplot database. B LAMA4 was knocked down in MNNG/HOS and 143B cells. The expression of LAMA4 was detected by Western blot. GAPDH was used as the loading control. C-D The cells (3000 cells/well) with or without LAMA4 depletion were tested for cell growth in the colony formation assay. Viable colonies after 1 week were counted and are shown (C). Data are depicted as bar graphs (D). E-F The migration of the indicated cells was detected by Transwell assays. Representative images of crystal violet-stained culture plates are shown (E). Data are depicted as bar graphs (F). G-H MNNG/HOS cells with or without LAMA4 knockdown were treated with 3 μM TM for 36 h. Cell apoptosis and cell viability were analysed by Western blot (G) and CCK8 assays (H). GAPDH was used as the loading control. I-J MNNG/HOS cells with or without LAMA4 knockdown were treated with 1 μM TG for 36 h. Cell apoptosis and cell viability were analysed by Western blot (I) and CCK8 assays (J). GAPDH was used as the loading control. K-M MNNG/HOS cells (10⁶ cells per mouse) with or without LAMA4 knockdown were injected subcutaneously into nude mice (n = 4). Representative images of xenograft tumours (K). The weights of the tumours were calculated and analysed (L). The expression levels of PARP, cleaved PARP and LAMA4 in tumours were measured by Western blot (M). Data in D, F, H, J, L were analysed by Student’s t test, *p < 0.05, **p < 0.01, ***p < 0.001