Cluster of differentiation 74 Plays a role in prognosis of the patients with hepatocellular carcinoma after curative resection / 中华检验医学杂志

ABSTRACT

Objective By analyzing the expression of cluster of differentiation 74 (CD74) in hepatocellular carcinoma (HCC) and HCC cell lines,the correlation between the level of CD74 expression and the patients' prognosis was investigated.MethodsThe expression of CD74 in high metastatic potential HCC cell lines(MHCC-LM3,MHCC-97H),low metastatic potential HCC cell line( MHCC-97L),and no metastatic potential HCC cell line(Hep-G2) were estimated by Western blot.The paraffin embedded tissues which include intra-tumor and paratumor tissues were collected from 320 patients who had received HCC curative surgical resection and 5 normal liver tissues from the donors of liver tranplantation.The high density tissue micro-array was made of these specimens. Immunol-histochemistry was applied to discover the different levels of CD74 in tumor,paratumor and normal liver tissues.Survival curves were generated by the Kaplan-Meier method and verified by the Logrank test.Cox proportional hazards regression analysis was applied to estimate the prognostic factors in multivariate analysis.ResultsThe expression level of CD74 was significantly higher in low metastatic potential and no metastatic potential HCC cell lines (MHCC-97L 1.224 ±0.014,Hep-G2 1.374 ±0.006) than that in high metastatic potential ones( MHCC-LM3 0.622 ±0.078,MHCC-97H 0.732 ± 0.083 ).Significant differences can be found between the groups (t =- 13.308,- 16.849,- 10.177,- 13.436,- 17.057; P ＜0.01 ).Meanwhile,in tumor tissues,the CD74 was expressed positively in 221 patients and negatively in 99 patients.But CD74 was expressed slightly in paratumor and negatively in 5 normal liver tissues.There's no significant differences between the groups categorization according to age,HBsAg,cirrhosis,AFP level,tumor number,tumor size,tumor capsule,blood vessel invasion,Edmondson Grades and tumor nodes metastasis classification (TNM) stages (x2 =0.053,0.141,1.200,0.000,0.277,1.975,0.263,1.044,0.000,0.433 ; P ＞ 0.05 ),except gender (x2 =3.954,P ＜ 0.05).Kaplan-Meier method showed that patients with positively expression of CD74 had better prognosis than others (x2 =5.620,P ＜ 0.05 ).Cox proportional hazards regression analysis showed that CD74 was a significant and independent prognostic factor of survival [ hazard ratio (HR) =0.721,95％confidence interval (CI) =0.522 - 0.996,P ＜ 0.05 ].Conclusion The expression of CD74 in hepatocellular carcinoma could be a biomarker of the prognosis and there's some potential correlation with cancer cell apoptosis.