Fig. 2.

C1GALT1 promotes malignant phenotypes in HNSCC cells. a Western blots showing overexpression of C1GALT1 in SAS cells, knockdown of C1GALT1 in OEC-M1 and FaDu cells, and knockout of C1GALT1 in SAS cells. SAS cells were transfected with empty pcDNA3.1 (Mock) or C1GLAT1/pcDNA3.1A (C1GALT1). OEC-M1 and FaDu cells were transfected with non-targeting siRNA (siCtr) or two independent siRNAs against C1GALT1 (siC1GALT1-1 and siC1GALT1-2). These cells were transfected for 48 h before further experiments. C1GALT1 was knocked out in SAS cells with the CRISPR/Cas9 system. C1GALT1 in parental cells (WT) and two C1GALT1 knockout clones (KO #8 and KO #22) were shown. GAPDH was an internal control. b Effects of C1GALT1 on viability of HNSCC cells. Cell viability was analyzed using MTT assays at different time points as indicated. Data are analyzed by Student’s t-test. **P < 0.01. c Effects of C1GALT1 on migration and invasion of HNSCC cells. Transwell migration and Matrigel invasion assays were performed to analyze cell migration and invasion, respectively. Results are represented as mean ± SD. Data are analyzed by Student’s t-test. *P < 0.05. **P < 0.01. d Effects of C1GALT1 knockout on tumor growth in vivo. Wild-type (WT) or C1GALT1-knockout (KO #22) SAS cells (5 × 10⁶) were injected subcutaneously into NOD-SCID mice. Upper panel, images of tumor xenografts. Scale bar, 1 cm. Lower panel, tumor growth curves. Results are represented as mean ± SD. Data are analyzed by Student’s t-test. **P < 0.01. e Effects of C1GALT1 knockout on tumor metastasis in vivo. Wild-type (WT) or C1GALT1-knockout (KO #22) SAS cells (1 × 10⁶) were injected into the tail vein of NOD-SCID mice. Left panel, representative images and HE staining of lungs. Arrows indicate metastatic tumor nodules in lungs. Right panel, numbers of tumor nodules in lungs of mice injected with WT or KO #22 SAS cells. Results are represented as mean ± SD. Data are analyzed by Student’s t-test. **P < 0.01