Hepatic perivascular epithelioid cell tumor in three patients.

Perivascular epithelioid cell tumor (PEComa) is a rare, soft tissue tumor that can occur in various locations. The present report included three patients (one male and two females; age range, 25-51 years) with hepatic PEComas. The collected data included the clinical manifestations, diagnosis, management, treatment, and prognosis. Since it is difficult to diagnose hepatic PEComas by imaging, the patients were diagnosed by tumor tissue examination such as immunohistochemistry, which was positive for HMB-45, Melan-A, and SMA on all slides. The tumor was composed of diverse tissues including smooth muscle, adipose tissue, and thick-walled blood vessels. During the follow-up period, one of the tumors was malignant (double-positive for CD34 and Ki-67) and recurred 3 months after surgery. In addition, malignant hepatic PEComas were reviewed in the literature, indicating that the majority of hepatic PEComas are benign, but few hepatic PEComas exhibit malignant behaviors in older female patients (>50 years of age) with abdominal discomfort and pain, larger tumor size (>10 cm), or positive staining for CD34 and Ki-67. In conclusion, there is no effective method to diagnose PEComas. Currently, the diagnosis of PEComas depends on immunohistochemical staining. Tumor resection and close follow-up are the principal methods for the management of PEComas.

Oleanolic acid attenuates liver ischemia reperfusion injury by HO-1/Sesn2 signaling pathway.

BACKGROUND: Ischemia reperfusion injury (IRI) is unavoidable in liver transplantation and hepatectomy. The present study aimed to explore the possible mechanism and the effect of oleanolic acid (OA) in hepatic IRI. METHODS: Mice were randomly divided into 6 groups based on different treatment. IRI model: The hepatic artery, portal vein, and bile duct to the left and median liver lobes (70% of the liver) were occluded with an atraumatic bulldog clamp for 90 minutes and then the clamp was removed for reperfusion. The mice were sacrificed 6 hours after reperfusion, and blood and liver tissues were collected. Liver injury was evaluated by biochemical and histopathologic examinations. The expressions of Sesn2, PI3K, Akt and heme oxygenase-1 (HO-1) were measured with quantitative real-time RT-PCR and Western blotting. RESULTS: The serum aminotransferases level and scores of hepatic histology were increased after reperfusion. The increase was attenuated by pretreatment with OA (P<0.01). Compared with the IR group, OA pretreatment significantly up-regulated the expression of Sesn2, PI3K, Akt and HO-1 in IR livers (P<0.05). Administration of zinc protoporphyrin (ZnPP), an inhibitor of HO-1, diminished the OA effect on HO-1 and Sesn2 expressions (P<0.05) and the protective effect of OA on IRI. CONCLUSIONS: Our results demonstrate that OA can attenuate hepatic IRI. The protective mechanism may be related to the OA-induced HO-1/Sesn2 signaling pathway.