Research Paper Volume 12, Issue 9 pp 7747—7760

TGF-β signaling regulates SPOP expression and promotes prostate cancer cell stemness

Figure 4. SPOP expression is downregulated in human proatate cancer. (A) SMAD3 expression levels in normal tissue and primary tumor of prostate through the TCGA data. Expression levels are presented as boxplots and were compared using an unpaired Student's t-test, ***P<0.001. (B) SPOP expression levels in normal tissue and primary tumor of prostate through the TCGA data. Expression levels are presented as boxplots and were compared using an unpaired Student's t-test, ***P<0.001. (C) Relative SPOP expression levels in parental sample and sphere sample of prostate cancer through the GEO data GSE19713. Expression levels are presented as boxplots and were compared using an unpaired Student's t-test, **P<0.01. (D) Relative TGFβR II expression levels in parental sample and sphere sample of prostate cancer through the GEO data GSE19713. Expression levels are presented as boxplots and were compared using an unpaired Student's t-test, **P<0.01. (E) Human prostate tumor specimens were stained with p-SMAD3 and SPOP separately using an IHC staining assay. Representative examples are shown. (F) The correlation between SPOP and p-SMAD3 protein levels in the human prostate tumor tissue array is shown. Statistical significance was determined by a χ2 test. R indicates the correlation coefficient. (G) Model for TGF-β signaling negatively regulates SPOP expression.