Duncan Spalding

Novel RNA oligonucleotide improves liver function and inhibits liver carcinogenesis in vivo

Hepatocellular carcinoma (HCC) occurs predominantly in patients with liver cirrhosis. Here we show an innovative RNA‐based targeted approach to enhance endogenous albumin production while reducing liver tumor burden. We designed short‐activating RNAs (saRNA) to enhance expression of C/EBPα (CCAAT/enhancer‐binding protein‐α), a transcriptional regulator and activator of albumin gene expression. Increased levels of both C/EBPα and albumin mRNA in addition to a 3‐fold increase in albumin secretion and 50% decrease in cell proliferation was observed in C/EBPα‐saRNA transfected HepG2 cells. Intravenous injection of C/EBPα‐saRNA in a cirrhotic rat model with multifocal liver tumors increased circulating serum albumin by over 30%, showing evidence of improved liver function. Tumor burden decreased by 80% (P = 0.003) with a 40% reduction in a marker of preneoplastic transformation. Since C/EBPα has known antiproliferative activities by way of retinoblastoma, p21, and cyclins, we used messenger RNA (mRNA) expression liver cancer‐specific microarray in C/EBPα‐saRNA‐transfected HepG2 cells to confirm down‐regulation of genes strongly enriched for negative regulation of apoptosis, angiogenesis, and metastasis. Up‐regulated genes were enriched for tumor suppressors and positive regulators of cell differentiation. A quantitative polymerase chain reaction (PCR) and western blot analysis of C/EBPα‐saRNA‐transfected cells suggested that in addition to the known antiproliferative targets of C/EBPα, we also observed suppression of interleukin (IL)6R, c‐Myc, and reduced STAT3 phosphorylation. Conclusion: A novel injectable saRNA‐oligonucleotide that enhances C/EBPα expression successfully reduces tumor burden and simultaneously improves liver function in a clinically relevant liver cirrhosis/HCC model. (Hepatology 2014;58:216–227)

Laparoscopic versus open pancreas resection for pancreatic neuroendocrine tumours: a systematic review and meta-analysis

BACKGROUND Over the last decade laparoscopic pancreatic surgery (LPS) has emerged as an alternative to open pancreatic surgery (OPS) in selected patients with neuroendocrine tumours (NET) of the pancreas (PNET). Evidence on the safety and efficacy of LPS is available from non-comparative studies. OBJECTIVES This study was designed as a meta-analysis of studies which allow a comparison of LPS and OPS for resection of PNET. METHODS Studies conducted from 1994 to 2012 and reporting on LPS and OPS were reviewed. Studies considered were required to report on outcomes in more than 10 patients on at least one of the following: operative time; hospital length of stay (LoS); intraoperative blood loss; postoperative morbidity; pancreatic fistula rates, and mortality. Outcomes were compared using weighted mean differences and odds ratios. RESULTS Eleven studies were included. These referred to 906 patients with PNET, of whom 22% underwent LPS and 78% underwent OPS. Laparoscopic pancreatic surgery was associated with a lower overall complication rate (38% in LPS versus 46% in OPS; P < 0.001). Blood loss and LoS were lower in LPS by 67 ml (P < 0.001) and 5 days (P < 0.001), respectively. There were no differences in rates of pancreatic fistula, operative time or mortality. CONCLUSIONS The nature of this meta-analysis is limited; nevertheless LPS for PNET appears to be safe and is associated with a reduced complication rate and shorter LoS than OPS.

Non-alcoholic fatty liver disease: A sign of systemic disease

Non-alcoholic fatty liver disease (NAFLD) is the most common form of liver disease and leading cause of cirrhosis in the United States and developed countries. NAFLD is closely associated with obesity, insulin resistance and metabolic syndrome, significantly contributing to the exacerbation of the latter. Although NAFLD represents the hepatic component of metabolic syndrome, it can also be found in patients prior to their presentation with other manifestations of the syndrome. The pathogenesis of NAFLD is complex and closely intertwined with insulin resistance and obesity. Several mechanisms are undoubtedly involved in its pathogenesis and progression. In this review, we bring together the current understanding of the pathogenesis that makes NAFLD a systemic disease.

Meta-analysis of drain amylase content on postoperative day 1 as a predictor of pancreatic fistula following pancreatic resection

Drain amylase content in the days immediately after major pancreatic resection has been investigated previously as a predictor of postoperative pancreatic fistula (POPF). Its accuracy, however, has not been determined conclusively. The purpose of this study was to evaluate the accuracy of drain amylase content on the first day after major pancreatic resection in predicting the occurrence of POPF.

Does neostigmine improve time to resolution of symptoms in acute colonic pseudo-obstruction?

A best evidence topic was written according to a structured protocol. In [patients with acute colonic pseudo-obstruction] is [neostigmine] superior to [conservative treatment] with respect to [duration of symptoms and complications]. In total 51 papers were found using the reported search, and ten of these represented the best evidence to answer the clinical question. The authors, date, journal, study type, population, main outcome measures and results are tabulated. We conclude that intravenous neostigmine is associated with significantly reduced duration of acute colonic pseudo-obstruction (ACPO) compared to conservative treatment alone. Neostigmine infusion should be administered with continuous cardiac monitoring for possible bradycardia, which may require treatment with atropine. Seven prospective analyses and one retrospective study showed that intravenous neostigmine reduces time to resolution of clinical and radiological features of ACPO. One prospective study showed that neostigmine is only effective in improving duration of ACPO when it is combined with proponalol. One prospective study showed no difference in time to resolution of ACPO between neostigmine and conservative treatment but this study was limited by small sample size, lack of radiological examinations and poor reporting of adverse effects. In four separate studies patients experienced bradycardia with intravenous neostigmine and this required treatment with atropine. No other significant adverse effects were reported. Overall, intravenous neostigmine is associated with a significant reduction in duration of ACPO. In addition to regularly reviewing patients for antic-cholinergic side effects, patients should undergo continuous cardiac monitoring for bradycardia. The wide variety in methodology and measurement of outcomes reinforce the need for higher power studies to improve patient selection and monitoring of outcomes.

Aptamer-Drug Conjugates of Active Metabolites of Nucleoside Analogs and Cytotoxic Agents Inhibit Pancreatic Tumor Cell Growth

Aptamer-drug conjugates (ApDCs) have the potential to improve the therapeutic index of traditional chemotherapeutic agents due to their ability to deliver cytotoxic drugs specifically to cancer cells while sparing normal cells. This study reports on the conjugation of cytotoxic drugs to an aptamer previously described by our group, the pancreatic cancer RNA aptamer P19. To this end, P19 was incorporated with gemcitabine and 5-fluorouracil (5-FU), or conjugated to monomethyl auristatin E (MMAE) and derivative of maytansine 1 (DM1). The ApDCs P19-dFdCMP and P19-5FdUMP were shown to induce the phosphorylation of histone H2AX on Ser139 (γ-H2AX) and significantly inhibited cell proliferation by 51%–53% in PANC-1 and by 54%–34% in the gemcitabine-resistant pancreatic cancer cell line AsPC-1 (p ≤ 0.0001). P19-MMAE and P19-DM1 caused mitotic G2/M phase arrest and inhibited cell proliferation by up to 56% in a dose-dependent manner when compared to the control group (p ≤ 0.001). In addition, the cytotoxicity of P19-MMAE and P19-DM1 in normal cells and the control human breast cancer cell line MCF7 was minimal. These results suggest that this approach may be useful in decreasing cytotoxic side effects in non-tumoral tissue.

Kupffer Cell-Derived Tnf Triggers Cholangiocellular Tumorigenesis through JNK due to Chronic Mitochondrial Dysfunction and ROS

Intrahepatic cholangiocarcinoma (ICC) is a highly malignant, heterogeneous cancer with poor treatment options. We found that mitochondrial dysfunction and oxidative stress trigger a niche favoring cholangiocellular overgrowth and tumorigenesis. Liver damage, reactive oxygen species (ROS) and paracrine tumor necrosis factor (Tnf) from Kupffer cells caused JNK-mediated cholangiocellular proliferation and oncogenic transformation. Anti-oxidant treatment, Kupffer cell depletion, Tnfr1 deletion, or JNK inhibition reduced cholangiocellular pre-neoplastic lesions. Liver-specific JNK1/2 deletion led to tumor reduction and enhanced survival in Akt/Notch- or p53/Kras-induced ICC models. In human ICC, high Tnf expression near ICC lesions, cholangiocellular JNK-phosphorylation, and ROS accumulation in surrounding hepatocytes are present. Thus, Kupffer cell-derived Tnf favors cholangiocellular proliferation/differentiation and carcinogenesis. Targeting the ROS/Tnf/JNK axis may provide opportunities for ICC therapy.

Kallistatin, a new and reliable biomarker for the diagnosis of liver cirrhosis.

Kallistatin, which protects organs and cells against inflammation, fibrosis and oxidative stress, is mainly synthesized and secreted in liver. However, its relationship to human liver disease remains unclear. The purpose of this study was to explore the relationship between serum kallistatin and clinical evidence of both cirrhosis and hepatocellular carcinoma (HCC), and to determine if serum kallistatin levels could be used as a diagnostic indicator of hepatic health status, especially human liver cirrhosis (LC). Our cohort consisted of 115 patients with clinically proven liver fibrosis (LF), LC, or HCC by liver biopsies, and 31 healthy controls (CON). Serum kallistatin levels were quantified by ELISA. Results of the present study demonstrated that irrespective of the underlying etiology, serum kallistatin levels were significantly lower in the LF/LC group when compared with the CON group. A decrease in serum kallistatin levels appeared to reflect the extent of cirrhosis, with the lowest levels associated with higher grades of cirrhosis. Patients with LC had a noticeable correlation between serum kallistatin levels and other serum biochemical indicators. The area under the curve (AUC) for LC, viral liver cirrhosis (VLC) and alcoholic liver cirrhosis (ALC) was 0.845, 0.757 and 0.931, respectively. In conclusion, our findings demonstrated that kallistatin, a plasma protein produced by the liver, can be a useful and reliable diagnostic indicator of hepatic health status, especially for LC.

Neoadjuvant chemotherapy and primary-first approach for rectal cancer with synchronous liver metastases.

Up to a quarter of patients with rectal cancer have synchronous liver metastases at the time of diagnosis. This is a predictor of poor outcome. There are no standardized guidelines for treatment. We reviewed the outcomes of our patients with synchronous rectal liver metastases treated with a curative intent by neoadjuvant chemotherapy with or without chemoradiotherapy followed by resection of the primary tumour and then liver metastases.

Is octreotide beneficial in patients undergoing pancreaticoduodenectomy? Best evidence topic (BET)

A best evidence topic was written according to a structured protocol. The question addressed was whether the prophylactic administration of somatostatin or somatostatin analogues in patients undergoing pancreaticoduodenectomy (Whipples procedure) is beneficial in terms of improved surgical outcomes, reduced morbidity or reduced mortality. A total of 118 papers were found using the reported searches of which 5 represented the best evidence (1 meta-analysis, 1 systematic review and 3 randomized control trials). The authors, date, journal, study type, population, main outcome measures and results were tabulated. There is evidence that the perioperative administration of somatostatin or somatostatin analogues reduces biochemical incidence of pancreatic fistula but, it is still unclear if there is a beneficial effect in the incidence of clinically significant pancreatic fistula. Further adequately powered trials with low risk of bias are necessary. From the available data, somatostatin or somatostatin analogues have no effect on mortality post Whipples. Interestingly, there are only limited data available on the cost-benefit and financial constraints imposed by this treatment, an issue that has only been addressed in a few studies.