Fig. 2.

CBS is upregulated in human colon cancer and correlates with worse clinical prognosis. A) Formalin-fixed paraffin-embedded sections of normal colonic mucosa, hyperplastic polyp and adenocarcinoma, stained with CBS antibodies showing a gradual increase in CBS expression corresponding to the severity of the disease. The panel was adapted from data published in Ref. [48]). B). CBS expression in human colon cancer biopsies compared to normal surrounding tissue. Representative western blots and summary of expression data are shown (mean ​± ​SEM). Arbitrary relative densitometry units were normalized with β-actin using image analysis software. ∗p ​< ​0.05 ​T (tumor) vs. N (normal surrounding tissue); n ​= ​15. The panel was redrawn from data presented in Ref. [49]. C) Effect of the CBS/CSE inhibitor AOAA (1 mM) and the CSE inhibitor PAG (3 mM) on H₂S production in homogenates of a colorectal cancer and patient-matched normal colonic tissue. Data are presented as mean ​± ​SEM of 3 independent experiments. ∗p ​< ​0.05 shows significant inhibition of H₂S production. The panel was redrawn from data presented in Ref. [6]. D) Representative images of CBS immunohistochemical staining in different-stage tumor tissues (n ​= ​90) in the microarray. Immunohistochemical score for CBS in different-stage colon tumor tissues in the microarray. (stage 1 ​= ​28 cases; stage 2 ​= ​28 cases; stage 3 ​= ​21 cases; stage 4 ​= ​13 cases). Data are presented as mean ​± ​SEM of at least 3 independent experiments. ∗p ​< ​0.05 shows significantly higher expression of CBS in tumors, compared to adjacent normal tissues. The panel was redrawn from data presented in Ref. [52]. E) CBS mRNA expression in 52 colon cancer tissues and paired adjacent normal colon tissues showing that CBS in tumor tissue is higher than in the surrounding normal tissue in the majority of the patients studied. The panel was redrawn from data presented in Ref. [50]. F) Survival curve showing the impact of CBS expression on overall survival in colon cancer from COAD dataset. p < 0.05 reflects higher survival rate in low-CBS-expressor patients. The panel was redrawn from data presented in Ref. [55]. G) Survival curve showing the impact of CBS expression on overall survival in colon cancer from TCGA-OV dataset. ∗p ​< ​0.05 reflects higher survival rate in low-CBS-expressor patients. The panel was redrawn from data presented in Ref. [52].