Fig 2: THBS4 expression is higher in normal mucosa than in tumour tissue. While the relative expression of THBS4 was quite low overall, THBS4 expression was significantly higher in peritumoural normal mucosa than in the tumour tissue. Median expression in normal mucosa was 0.04 vs. 0.01 for tumour tissue (p = 0.0035). Circular and diamond shaped dots represent individual data point for normal and tumours samples, respectively.

Fig 3: The THBS4 protein appears to be secreted. THBS4 protein is not expressed or is expressed at low levels in normal cells, especially towards the luminal surface. Tumour expression of THBS4 is heterogeneous, with generally no expression but occasional areas of strong expression and packaging in vesicular structures.

Fig 4: Over-expression of THBS4 significantly decreases colony formation in CRC cell lines. Forced over-expression of THBS4 significantly decreases colony formation in colorectal cancer cell lines regardless of their baseline expression levels. The average reduction in colony formation following THBS4 over-expression was 50-60% compared with vector-only controls. This consistent and significant reduction in colony forming ability may indicate that high levels of this protein could correlate with reduced tumour cell growth.

Fig 5: THBS4 methylation is significantly higher in neoplastic tissue compared to adjacent normal tissue. THBS4 methylation was significantly higher in neoplastic tissues compared to the adjacent normal tissue (p < 0.0001). The median PMR in normal mucosa was 0.06 compared with a PMR of 2.6 in tumour tissue.