Fig 2: Knockdown of GGCT and MRPL9 inhibited tumor growth and metastasis in vivo. (A,B) The Xenogen IVIS Lumina System detects the bioluminescence intensity of subcutaneous xenografts in nude mice in vivo, and performs statistical analysis on the fluorescence signals (n = 3). (C) Subcutaneous xenografts in nude mice. (D,E) Statistical analysis of mass and volume of subcutaneous xenografts (n = 3). (F) The Xenogen IVIS Lumina System detects bioluminescence intensity in the lungs of nude mice in vivo (top) and ex vivo (bottom) (n = 3). (G) The line chart denotes luciferase bioluminescence emitted from the lungs in each group over time (0–28 days). (H) Statistical analysis of bioluminescence intensity in the lungs of nude mice in vivo (n = 3). (I) Statistical analysis results of bioluminescence intensity of nude mouse lung tissue in vitro (n = 3). (J) HE staining was used to analyze the metastases in the lungs of nude mice. Measurement data (mean ± standard deviation) between two groups were compared by paired t test, and multiple groups were compared by one-way analysis of variance (ANOVA). “**” represents p = 0.01, “*” represents p = 0.05.

Fig 3: GGCT regulates the MAPK/ERK signaling pathway by interacting with MRPL9. (A). The protein expression levels of P38, p-P38, ERK and p-ERK in the shGGCT/shMRPL9/sh-GGCT + shMRPL9 group were detected by Western blot in K1/BCPAP cells. (B) The expression levels of P38, p-P38, ERK and p-ERK in the shGGCT/shMRPL9/sh-GGCT + shMRPL9 group in K1 cell line were analyzed by J image, normalized to Actin (n = 3). (C) The expression levels of P38, p-P38, ERK and p-ERK in the shGGCT/shMRPL9/sh-GGCT + shMRPL9 group in BCPAP cell line were analyzed by J image, normalized to Actin (n = 3) Measurement data (mean ± standard deviation) between two groups were compared by paired t test. “**” represents p = 0.01.

Fig 4: GGCT is highly expressed in PTC. (A) Representative images of GGCT immunohistochemistry (IHC) of normal PTC tissue (left) and PTC tissue (right) (scar bar = 100 µm). (B) Statistics of GGCT immunohistochemical score of PTC group (n = 26) and normal group (n = 26) (Each dot represents a patient’s normal thyroid tissue, and each triangle represents a patient’s PTC tissue). (C) Correlation analysis of GGCT and MRPL9 IHC scores. (D) Representative Western blot of GGCT protein in 26 pairs of PTC tissues and normal tissues. (E) Western blot results were quantified and normalized to Actin (n = 3). (F) RT-qPCR analysis detected the expression level of GGCT in Nthy-ori 3.1, TPC-1, K1, BCPAP cell lines (n = 3). (G) Western blot detection of GGCT protein expression levels in Nthy-ori 3.1, TPC-1, K1, and BCPAP cell lines. (H) Western blot results were quantified and normalized to Actin (n = 3). Measurement data (mean ± standard deviation) between two groups were compared by paired t test, and multiple groups were compared by one-way analysis of variance (ANOVA) with Tukey’s post hoc test. “*” represents p = 0.05, “**” represents p = 0.01.