Expression level of Pre B cell leukemia homeobox 2 correlates with poor prognosis of gastric adenocarcinoma and esophageal squamous cell carcinoma.

Pre B cell leukemia homeobox 2 (PBX2), a member of PBX family, acts as a co-factor of homeobox proteins to regulate proliferation and differentiation of tumor cells. Our recent study revealed prognostic significance of PBX2 expression in non-small cell lung carcinoma. The significance of PBX2 expression was examined in cases with gastric cancer (GC) and esophageal squamous cell carcinoma (ESCC), and the role of PBX2 in tumor behavior was evaluated in GC and ESCC cell lines of knocked-down PBX2 expression. Expression level of PBX2 was immunohistochemically examined in 94 patients of GC and 64 patients of ESCC. Staining intensity for PBX2 was categorized as equal to or stronger (level 1) and weaker (level 2) than that of endothelial cells. Cases with level 1 expression in more than 20% of tumor were defined as high and others low expression. Patients with low PBX2 expression showed a better prognosis than those with high expression in both GC and ESCC. Multivariate analysis revealed PBX2 expression to be an independent prognosticator for both GC and ESCC. Knocked-down expression of PBX2 in GC and ESCC cell lines resulted in decrease of in vitro colony formation and in vivo tumorigenic activities, but proliferative and invasive activities did not change. Under serum depletion, apoptotic cell proportion was higher in PBX2 knocked-down cells than in control cells. The knock-down of PBX2 reduced Bcl-2 expression. Taken together, the high expression level of PBX2 was an independent negative prognosticator for both GC and ESCC, and PBX2 might promote tumor growth through suppression of apoptosis.

[Expression of nm23 and KAI1 and their clinical significance in gallbladder adenocarcinoma].

OBJECTIVE: To investigate the expression of two tumor metastasis suppressor genes nm23 and KAI1 in gallbladder adenocarcinoma, and their clinicopathological significance. METHODS: Specimens and clinical data from 31 gallbladder adenocarcinoma patients were collected. Histopathological grading and the expression of nm23 and KAI1 were detected by HE and immunohistochemical staining, respectively. All cases were followed up for at least three years. RESULTS: Immunohistochemical staining showed that the positive rate of nm23 and KAI1 proteins was 71.0% (22/31) and 61.3% (19/31), respectively. The positive expression rates of nm23 and KAI1 proteins in the early stage carcinomas were significantly higher than those in the moderate and advanced stage ones (P exact = 0.0051 and P exact = 0.0084), and both had an negative correlation with clinicopathologic stage (P trend = 0.0047 and P trend = 0.0058). There was a significant difference in the expression of nm23 and KAI1 proteins among well, moderately and poorly differentiated carcinomas (P exact = 0.0328 and P exact = 0.0020). The expression of nm23 and KAI1 was positively correlated with histopathological grade (P trend = 0.0086 and P trend = 0.0006). There was also a significant difference in the expression of nm23 and KAI1 proteins between 17 survival and 14 dead patients (P exact = 0.0038 and P exact = 0.0001 ). A synergistic effect of nm23 and KAI1 protein on the survival was observed , and seemed to be more important than any individual gene alone (P exact = 0.0005). CONCLUSION: The expressions of nm23 and KAI1 proteins are negatively correlated with clinical stage, but positively with histopathological grade in gallbladder adenocarcinoma. These two tumor metastasis suppressor genes may act synergistically to inhibit the tumor metastasis.

Effect of Qingyitang on activity of intracellular Ca2+-Mg2+-ATPase in rats with acute pancreatitis.

AIM: To study the change of intracellular calcium-magnesium ATPase (Ca(2+)-Mg(2+)-ATPase) activity in pancreas, liver and kidney tissues of rats with acute pancreatitis (AP), and to investigate the effects of Qingyitang (QYT) (Decoction for clearing the pancreas) and tetrandrine (Tet) and vitamin E (VitE) on the activity of Ca(2+)-Mg(2+)-ATPase. METHODS: One hundred and five Sprague-Dawley rats were randomly divided into: normal control group, AP group, treatment group with QYT (1 ml/100 g) or Tet (0.4 ml/100 g) or VitE (100 mg/kg). AP model was prepared by a retrograde injection of sodium taurocholate into the pancreatic duct. Tissues of pancreas, liver and kidney of the animals were taken at 1 h, 5 h, 10 h respectively after AP induction, and the activity of Ca(2+)-Mg(2+)-ATPase was studied using enzyme-histochemistry staining. Meanwhile, the expression of Ca(2+)-Mg(2+)-ATPase of the tissues was studied by RT-PCR. RESULTS: The results showed that the positive rate of Ca(2+)-Mg(2+)-ATPase in AP group (8.3%, 25%, 29.2%) was lower than that in normal control group (100%) in all tissues (P<0.01), the positive rate of Ca(2+)-Mg(2+)-ATPase in treatment group with QYT (58.3%, 83.3%, 83.3%), Tet (50.0%, 70.8%, 75.0%) and VitE (54.2%, 75.0%, 79.2%) was higher than that in AP group (8.3%, 25.0%, 29.2%) in all tissues (P<0.01). RT-PCR results demonstrated that in treatment groups Ca(2+)-Mg(2+)-ATPase gene expression in pancreas tissue was higher than that in AP group at the observing time points, and the expression at 5 h was higher than that at 1 h. The expression of Ca(2+)-Mg(2+)-ATPase in liver tissue was positive, but without significant difference between different groups. CONCLUSION: The activity and expression of intracellular Ca(2+)-Mg(2+)-ATPase decreased in rats with AP, suggesting that Ca(2+)-Mg(2+)-ATPase may contribute to the occurrence and development of cellular calcium overload in AP. QYT, Tet and VitE can increase the activity and expression of Ca(2+)-Mg(2+)-ATPase and may relieve intracellular calcium overload to protect the tissue and cells from injuries.