Expression of serine protease SNC19/matriptase and its inhibitor hepatocyte growth factor activator inhibitor type 1 in normal and malignant tissues of gastrointestinal tract.

AIM

To provide the expression profile of serine protease SNC19/matriptase and its inhibitor hepatocyte growth factor activator inhibitor type 1 (HAI-1) in normal and malignant tissues of gastrointestinal tract at mRNA level for further study on their correlations with tumor progression and metastasis.

METHODS

Total RNAs were prepared from 37 samples of colorectal cancer tissues, 40 samples of gastric cancer tissues, and their adjacent normal tissues. The expression of SNC19/matriptase and HAI-1 in these samples was detected by real-time fluorescent quantitative PCR using glyceraldehyde-3-phosphate dehydrogenase as internal standard, and the clinical significance for the correlation with clinicopathological parameters was evaluated.

RESULTS

In gastric cancer tissues the expression of HAI-1 and SNC19/matriptase was significantly lower than that in the corresponding adjacent normal tissues (Z = -3.280, P = 0.006; Z = -4.651, P = 0.000). HAI-1:SNC19/matriptase ratio showed no difference between normal and malignant tissues (P>0.05). Analysis of clinicopathological parameters showed decreased expression of HAI-1 and HAI-1:SNC19/matriptase ratio associated with stage III/IV gastric tumors as compared to stage I/II ones (Z = -2.140, P = 0.031; Z = -2.155, P = 0.031), and with lymph node-positive gastric cancer tissues as compared to lymph node-negative ones (Z = -2.081, P = 0.036; Z = -2.686, P = 0.006). The expression of SNC19/matriptase had no relationship with stages and lymph node metastasis (P>0.05). The expression of HAI-1 and HAI-1:SNC19/matriptase ratio increased in well-differentiated gastric cancer tissues, but there was no statistical significance (P>0.05). The difference of SNC19/matriptase expression was not significant in gastric cancer tissues of different histological differentiation status (P>0.05). In colorectal cancer tissues, the expression of HAI-1 and SNC19/matriptase was also markedly lower than that in their adjacent normal tissues (Z = -3.100, P = 0.002; Z = -2.731, P = 0.006), whereas HAI-1:SNC19/matriptase ratio showed no difference. Decreased expression of HAI-1 was associated with increased invasive depth and lymph node metastasis, but there was no statistical significance (P>0.05). The difference of SNC19/matriptase expression and HAI-1:SNC19/matriptase ratio was not significant in different stages and different lymph node metastasis status (P>0.05). The expression of SNC19/matriptase, HAI-1 or HAI-1:SNC19/martiptase ratio showed no difference in colorectal cancer tissues of different histological differentiation status (P>0.05).

CONCLUSION

The expressions of SNC19/matriptase and its inhibitor HAI-1 are decreased in gastrointestinal cancer tissues compared to their normal counterparts, and the decreased expression of HAI-1 may correlate with invasion and lymph node metastasis. The possible mechanisms involved need to be further investigated.