Cancer and liver transplantation

LASP2 is downregulated in human liver cancer and contributes to hepatoblastoma cell malignant phenotypes through MAPK/ERK pathway

LASP2 was recently demonstrated to serve as multifaceted roles in several types of cancers. However, its underlying mechanism in the progression of human liver cancer has not been explored. The aims of the current study were to detect LASP2 expression in a liver tissue microarray, and to determine whether LASP2 contributes to malignant phenotypes of HepG2 human hepatoblastoma cells. Our results revealed that LASP2 expression was downregulated in liver cancer tissues relative to normal non-cancerous tissues, and its downregulated expression was closely correlated with malignant process of liver cancer. In vitro, upregulation of LASP2 expression by transfection with LASP2 vector significantly suppressed HepG2 cells viability, colony formation and migration activities. Conversely, the viability, colony formation and migration abilities of HepG2 cells were increased when downregulating LASP2 expression by transfection with small interfering RNA targeting LASP2. Interaction study showed that silencing of LASP2 in HepG2 cells triggered high expression of Cyclin D1, ERK and p-ERK, and low expression of Bax, respectively. In addition, LASP2 silencing-induced malignant phenotypes were further attenuated after HepG2 cells treatment with ERK1/2 blocker PD98059. Collectively, our data suggest a link between LASP2 and MAPK/ERK axis in the development of hepatoblastoma and LASP2 may be a potential marker for assessment of liver cancer prognosis and staging.

MDR1 gene polymorphisms and risk of recurrence in patients With hepatocellular carcinoma after liver transplantation

BACKGROUND AND OBJECTIVES

Recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT) remains a major cause of post-LT death. However, currently there is still lacking the markers to reliably predict recurrence. This study was undertaken to evaluate the association between three polymorphisms (C1236T, G2677A/T, C3435T) of Multidrug resistance 1 (MDR1) gene and the risk of recurrence after LT.

METHODS

Genomic DNA of 99 HCC patients undergoing LT was extracted from peripheral blood lymphocytes and genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism assay. Cox proportional hazard model was used to estimate the hazard ratios associated with polymorphisms.

RESULTS

During a mean follow-up of 14.9 months, 49 patients experienced recurrence. The association between recurrence-free and 2677A carrier (carrying at least one variant A allele) was significant (P = 0.019). However, no significant association was observed in other polymorphisms. Patients with 2677A carrier conferred a 63% reduction in recurrence risk compared with 2677A non-carrier (odds ratio: 0.374; 95% confidence interval: 0.177-0.788; P = 0.010). The median recurrence-free survival for 2677A carrier group was significantly longer than that for 2677A non-carrier group (44.2 vs. 10.5 months, P = 0.015).

CONCLUSION

The polymorphism of MDR1 gene may be a valuable molecular marker for HCC recurrence after LT.

Liver transplantation in association with hepatocellular carcinoma: an update of the International Tumor Registry

Hepatocellular carcinoma is an epithelial tumor derived from hepatocytes that accounts for more than 80% of all primary hepatic tumors. The severity of the underlying disease is almost always the key factor in deciding whether to consider liver resection or transplantation as its treatment. Data in our registry corresponding to almost 800 patients from transplant centers throughout the world showed that patient survival after liver transplantation was significantly affected by histologic grade, tumor size >5 cm, and the presence of positive nodes. Recurrence-free survival showed a correlation with tumor size >5 cm, positive nodes, bilobar spread, and vascular invasion. At the present time, 59% of patients in our registry are alive, 84% of whom are free of tumor. Of those who died, half did so without evidence of tumor.

Treatment of unresectable hepatoblastoma with liver transplantation in the pediatric population

The purpose of our study was to evaluate the outcome of children who underwent liver transplantation as treatment for unresectable hepatoblastoma. We prospectively collected data on 311 consecutive liver transplants performed at Children's Medical Center of Dallas between October 1984 and November 2000. There were nine recipients (five boys, four girls) with a diagnosis of unresectable hepatoblastoma. Postoperative survival of those currently alive ranged from 6 months to 16 years (mean 6.4 years, median 7.7 years). All recipients received preoperative chemotherapy: 67% received postoperative chemotherapy. Mean AFP level prior to transplantation was 1 448000 ng/mL. Mean age at diagnosis was 0.81 years. Mean age at transplantation was 1.87 years. Only two patients experienced acute cellular rejection in the postoperative period. There was a total of three deaths and one recurrence. The only instance in which AFP levels did not decrease to low or undetectable levels post-transplantation was in the patient with recurrent tumor. Liver transplantation has an established role in the treatment of hepatoblastoma. It accounted for 3% of pediatric liver transplants, and provided the only opportunity for survival in otherwise incurable patients. Early diagnosis and treatment were found to be associated with better results. Response to chemotherapy may be an important factor influencing survival. Rising AFP levels after transplantation are associated with recurrence.