[Expression and significance of SARI and CCN1 in human colorectal carcinomas].

Objective: To explore the expressions of SARI (suppressor of AP-1, regulated by IFN) and connective tissue growth factor/cysteine-rich 61/nephroblastoma-1 (CCN1) and clarify their influences on the occurrence, development and prognosis of colorectal carcinoma (CRC).

Methods: Real-time PCR (polymerase chain reaction) was used to confirm the expressions of SARI and CCN1 at the mRNA level in 32 fresh tissue samples. And the expressions of Caco-2, HT-29 and Lovo were also detected by RT-PCR (reverse transcription-PCR) in cell lines. Tissue specimens were obtained from 116 cases of CRC and the expressions of SARI and CCN1 for each specimen detected by immunohistochemistry. The correlations between the expressions of SARI and CCN1 proteins were summarized. The relationships between the expression levels of SARI and CCN1 and their clinical features in primary CRC were analyzed respectively. The effects of expression levels of SARI and CCN1 proteins on the prognosis were also assessed in 116 CRC cases.

Results: The expressions of SARI and CCN1 at the mRNA level in fresh cancerous tissues and cell lines decreased and became up-regulated respectively. The positive rate of SARI protein expression was 76.7% and 28.4% in cancerous and noncancerous tissues respectively (P < 0.05). The positive rate of CCN1 protein expression was 26.7% and 74.1% in cancerous and noncancerous tissues respectively (P < 0.05). A negative correlation was observed between the expressions of SARI and CCN1 (r = -0.24, P < 0.05). The negative expression of SARI correlated with a low grade of differentiation, deep infiltration depth and high TNM staging (P < 0.05). A positive expression of CCN1 correlated with deep infiltration depth and high TNM staging (P < 0.05) while a negative expression of SARI correlated with a lower survival rate than that of a positive expression (χ(2) = 8.47, P < 0.05); additionally, the survival rate of patients with a negative expression of SARI plus a positive expression of CCN1 was further lowered (χ(2) = 12.56, P < 0.05).

Conclusion: The aberrant expressions of SARI and CCN1 correlate with the malignant biobehaviors of CRC. And a negative expression of SARI correlates with a worse prognosis of CRC.