Circulating DNA is a potential biomarker for tumor diagnosis and prognosis. This study was aimed to quantify the circulating DNA in plasma from patients with hepatocellular carcinoma (HCC) using quantitative PCR and evaluate its potential clinical value. Blood samples were collected from 72 patients with HCC, 37 with liver cirrhosis or chronic hepatitis and 41 healthy volunteers. Plasma DNA was extracted and quantified by a real-time quantitative PCR method. The diagnostic and prognostic value of plasma DNA analysis for HCC was evaluated. DNA levels in the HCC plasma (median: 173 ng/mL) were significantly higher than those in the healthy controls (9 ng/mL) or control benign patients (46 ng/mL) (P < 0.001). The area under the receiver-operation characteristic (ROC) curve (AUC) assessing plasma DNA was 0.949 for healthy controls and 0.874 for control patients. Plasma DNA detection could discriminate HCC from normal controls with 90.2% sensitivity and 90.3% specificity at the cut-off value of 18.2 ng/mL. Combined ROC analyses using plasma DNA and serum AFP revealed an elevated AUC of 0.974 with 95.1% sensitivity and 94.4% specificity in discriminating HCC from normal controls. The plasma DNA levels were positively associated with tumor size (P = 0.012), and were significantly elevated in HCC patients with intrahepatic spreading or vascular invasion (P = 0.035). The overall survival time of patients with high plasma DNA levels showed a shortened tread when compared with that of patients with low plasma DNA concentrations (P = 0.071). Plasma DNA may be a valuable noninvasive tool for the detecting and predicting the metastasis potential of HCC; and the prognostic value of plasma DNA needed further investigation.

Background and aims Reg4 is a recently discovered member of the regenerating gene family with distinctive expression profiles in primary cancers. To date, the physiological function of Reg4 is poorly understood. Previously, the authors found that Reg4 was markedly upregulated during acute pancreatitis (AP). The aim of this study was to investigate the role of Reg4 in experimental pancreatitis. Methods AP was induced in C57BL/6 mice by administration of either l-arginine or caerulein, and Reg4 expression was assessed by immunofluorescence, reverse transcriptase (RT)-PCR and western blot analyses. Recombinant human Reg4 protein (rReg4), heat-inactivated Reg4, neutralising antibody and vehicle were also administered to mice by subcutaneous injection. The severity of AP was determined by measuring amylase and lipase activities in the serum and histological grading. The effect of rReg4 on cell death was examined and epidermal growth factor receptor (EGFR), p-EGFR, Akt, p-Akt, Bcl-2 and Bcl-xL expression were assessed by western blot analysis of isolated murine acinar cells treated with l-arginine. Results Reg4 mRNA and protein were markedly upregulated during arginine-induced pancreatitis. Reg4 was widely expressed in residual acinar cells around the islets and regenerating metaplastic epithelium. rReg4 could protect against arginine-induced necrosis of acinar cells both in vivo and in vitro. This protective effect was also confirmed in the caerulein-induced murine model of AP. It was shown that arginine induced expression of Bcl-2 and Bcl-xL, while rReg4 upregulated Bcl-2 and Bcl-xL expression by activating the EGFR/Akt pathway. The upregulation of Bcl-xL correlated inversely with cell necrosis in isolated pancreatic acinar cells. Conclusions The data suggest that Reg4 may protect against acinar cell necrosis in experimental pancreatitis by enhancing the expression of Bcl-2 and Bcl-xL via activation of the EGFR/Akt signalling pathway.

Piperlongumine (PL), a natural alkaloid present in the fruit of the Long pepper, is known to exhibit notable anti-cancer effects. Nonetheless, the anti-tumor effect of PL in lung cancer cells still remains unclear. In the present study, we reported the chemotherapeutic effects of PL using in vitro and in vivo models. We showed that PL displayed potent anti-neoplastic activity against lung cancer A549 cells as well as corresponding docetaxel-resistant A549/DTX cells. In addition, we found that PL induced apoptosis in both A549 and A549/DTX cells. PL also induced autophagy in A549/DTX cells. Moreover, autophagy-specific inhibitors (3-methyladenine) or Beclin1 and Atg 5 small interfering RNAs (siRNAs) enhanced PL-induced apoptosis, indicating that PL-mediated autophagy may protect A549/DTX cells from undergoing apoptotic cell death. Furthermore, we observed the inhibition of phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway by PL. Finally, PL inhibited the growth of A549/DTX xenograft tumors, which was associated with inhibition of cell proliferation, induction of apoptosis of tumor cells and decreased expression of p-Akt and p-mTOR in tumor xenograft tissues. In summary, our study demonstrated that PL induced apoptosis and autophagy through modulation of the PI3K/Akt/mTOR pathway in human lung cancer cells. This study may provide a rationale for future clinical application using PL as a chemotherapeutic agent for lung cancer.