Research Paper Volume 11, Issue 21 pp 9643—9660

Oncogenic USP22 supports gastric cancer growth and metastasis by activating c-Myc/NAMPT/SIRT1-dependent FOXO1 and YAP signaling

Figure 6. USP22 depletion reduces in vivo GC growth and metastasis. Six-week-old male SCID mice were subcutaneously injected with stably-expressed pLKO.1-shUSP22-1 or pLKO.1 BGC-823-luc cells into the hind flanks or through the tail vein. (A) Histogram shows tumor volume at weeks 1, 2, 3 and 4 after subcutaneous injection of SCID mice (n=5 each) with BGC-823-luc cells stably-expressing pLKO.1-shUSP22-1 or pLKO.1 BGC-823-luc cells into the hind flanks at 1, 2, 3 and 4 weeks. (B) Analysis of tumor growth progression by in vivo luciferase imaging of the xenografts at day 21 after subcutaneous injection of SCID mice (n=5 each) with stably-expressed pLKO.1-shUSP22-1 or pLKO.1 BGC-823-luc cells. (C) Representative photographs of xenograft tumors at day 42 from SCID mice subcutaneously injected with stably-expressed pLKO.1-shUSP22-1 or pLKO.1 BGC-823-luc cells. (D) TUNEL assay results show the total number of apoptotic cells in the xenograft tumor sections derived at day 42 from from SCID mice subcutaneously injected with stably-expressed pLKO.1-shUSP22-1 or pLKO.1 BGC-823-luc cells. (E) Representative images and (F) Total number of s metastatic nodules in the lungs at day 28 from SCID mice that were injected with stably-expressed pLKO.1-shUSP22-1 or pLKO.1 BGC-823-luc cells. Note: Data are expressed as mean ± SD of three replicates; *p < 0.05, **p < 0.01 compared with the mock or pLKO.1 group.