OBJECTIVETo investigate the expression of cAMP-dependent protein kinase inhibitor beta (PKIB) in colorectal carcinoma (CRC) and its association with the clinicopathological factors of the patients.

METHODSThe expression of PKIB mRNA was detected with quantitative real-time PCR in 34 CRC tissues and paired adjacent tissues. Immunohistochemistry was used to detect the expression of PKIB protein in 72 CRC tissue specimens, and the relationship between PKIB protein expression and the clinicopathological features of the patients was analyzed.

RESULTSThe expression of PKIB mRNA was significantly higher in CRC tissues than in the paired asjacent tissues (P<0.0001). The expression of PKIB protein in CRC patients was closely related with tumor infiltration (T stage) (P=0.038) but not with age, gender, tumor size, location, lymph node metastasis (N stage) or distant metastasis (M stage) (P>0.05). The survival time of patients with high PKIB expressions was significantly shorter than that of patients with low PKIB expressions (70.532∓6.190 vs 93.500∓5.847 months, P=0.023).

CONCLUSIONA high expression of PKIB in CRC is positively correlated with tumor infiltration (T stage) and a poor prognosis, suggesting an important role of PKIB in the development of CRC and its value as an indicator for prognostic evaluation of CRC patients.