To investigate the expression of cell cycle checkpoint kinase 1 (Chk1) and its impact on the invasion capacity of hepatocellular carcinoma (HCC).

Samples of HCC tissues and adjacent non-tumor tissues from 127 patients undergoing radical hepatectomy in Cancer Center of Guangzhou Medical University from June 2005 to June 2010 were collected. The informed consents of all patients were obtained and the ethical committee approval was received. The patients included 116 males and 11 females with age ranging from 23 to 77 years old and a median age of 50 years old. The expression of Chk1 was detected by immunohistochemistry, and Transwell cell invasion assay was performed using HCC cells Huh7 and MHCC-97H. The experiment was divided into two groups. Chk1 small-molecule inhibitor G?6976 was added in Chk1 inhibitor group (inhibitor group). Dimethyl sulfoxide (DMSO, 0.1%) was added in control group. The expression of Chk1 in HCC tissues and adjacent non-tumor tissues, the relation between Chk1 expression and clinicopathological indicators were observed. The difference of cell-membrane penetrating count in two groups was compared using t test. The comparison of rates was conducted using Chi-square test.

The positive rate of Chk1 in HCC tissues [80.3% (102/127)] was significantly higher than that in adjacent non-tumor tissues [15.0% (19/127)] (χ²=108.700, P<0.05). High expression of Chk1 was observed in HCC tissues of patients with multiple tumors, non-coating tumors or early tumor recurrence after operation (χ²= 6.289, 4.713, 5.039; P<0.05). The cell-membrane penetrating counts of HCC cells Huh7 and MHCC-97H in inhibitor group (127±8, 136±10) were significantly lower than those in control group (174±11, 188±13) ( t =-3.402, -3.136; P<0.05).

High expression of Chk1 can be observed in HCC tissues. It’s associated with the invasion and metastasis of HCC. The Chk1 inhibitor can effectively suppress the invasion capacity of HCC cells.