Prostate-specific membrane antigen expression in hepatocellular carcinoma,cholangiocarcinoma,and liver cirrhosis

BACKGROUND Primary liver cancer includes three subtypes:Hepatocellular carcinoma(HCC),intrahepatic cholangiocarcinoma(CCA),and combined hepatocellular carcinoma.Patients with primary liver cancer experienced poor prognosis and high mortality,so early detection of liver cancer and improved management of metastases are both key strategies to reduce the death toll from liver cancer.Prostate-specific membrane antigen(PSMA)expression in the tumor-associated neovasculature of nonprostate malignancies including liver cancer has been reported recently,but conclusive evidence of PSMA expression based on the pathological type of liver cancer remains limited.AIM To study the expression of PSMA in HCC,CCA,and liver cirrhosis.METHODS A total of 446 formalin-fixed paraffin-embedded(FFPE)liver tumor and liver cirrhosis tissue samples were obtained retrospectively from the Pathology Department of Tongji Hospital.Immunohistochemistry was used to detect PSMA expression in these 446 FFPE liver biopsy specimens(213 HCC,203 CCA,and 30 liver cirrhosis).The tumor compartment and the associated neovascular endothelium were separately analyzed.PSMA expression was examined by two certified pathologists,and the final results were presented in a 4-point scoring system(0-3 points).Correlation between PSMA expression and clinicopathological information was also assessed.RESULTS PSMA was expressed primarily in the neovascular endothelium associated with tumors.The positive rate of PSMA staining in HCC was significantly higher than that in CCA(86.8%vs 79.3%;P=0.001)but was only 6.6%in liver cirrhosis(P=0.000).HCC cases had more 3-score PSMA staining than CCA had(89/213,41.8%vs 35/203,17.2%;P=0.001).PSMA expression correlated positively with the stage and grade of HCC and CCA.In both liver cancer subtypes,there were more PSMA+cases in stages III–V diseases than in stages I and II.High staining intensity of PSMA was more frequently observed in liver cancers at high grade and advanced stage.There was no significant association of PSMA expression with sex,age,region,α-fetoprotein,hepatitis B surface antigen,or tumor size in both tumor subtypes.CONCLUSION Neovascular PSMA may be a promising marker to differentiate HCC from liver cirrhosis and a prognostic marker for anti-tumor angiogenesis therapy for HCC.

Upgrade of the magnetic diagnostic system for restart of HT-6M operation

The HT-6M tokamak at the Thailand Institute of Nuclear Technology has been restarted.In order to ensure the smooth breakdown of plasma and obtain plasma discharge parameters,optimization of the poloidal field coils and upgrade of the magnetic diagnostics are described in this article.A perfect null field(stray field in the main chamber<10 G)is obtained using an ohmic heating field.To obtain important information about the plasma,an external magnetic diagnostics system is designed and calibrated,including a Rogowski coil(measuring plasma current),a magnetic probe(measuring external field),diamagnetic loops(measuringβ_(p))and so on.In order to realize high-frequency signal measurement and transmission,a series of frequency responses with the magnetic probe and transmission line are tested.Later,to verify the null field,a fitting code is developed to reconstruct the stray field in the vacuum chamber based on magnetic probe measurements and flux loops.The results show that the error is within 1.5%.This indicates the accuracy of the magnetic measurement system and ensures the preparation for the breakdown of plasma.