A genomic enhancer signature associates with hepatocellular carcinoma prognosis.

Background & Aims: Lifestyle and environmental-related exposures are important risk factors for hepatocellular carcinoma (HCC), suggesting that epigenetic dysregulation significantly underpins HCC. We profiled 30 surgically resected tumours and the matched adjacent normal tissues to understand the aberrant epigenetic events associated with HCC. Methods: We identified tumour differential enhancers and the associated genes by analysing H3K27 acetylation (H3K27ac) chromatin immunoprecipitation sequencing (ChIP-seq) and Hi-C/HiChIP data from the resected tumour samples of 30 patients with early-stage HCC. This epigenome dataset was analysed with previously reported genome and transcriptome data of the overlapping group of patients from the same cohort. We performed patient-specific differential expression testing using multiregion sequencing data to identify genes that undergo both enhancer and gene expression changes. Based on the genes selected, we identified two patient groups and performed a recurrence-free survival analysis. Results: We observed large-scale changes in the enhancer distribution between HCC tumours and the adjacent normal samples. Many of the gain-in-tumour enhancers showed corresponding upregulation of the associated genes and vice versa, but much of the enhancer and gene expression changes were patient-specific. A subset of the upregulated genes was activated in a subgroup of patients' tumours. Recurrence-free survival analysis revealed that the patients with a more robust upregulation of those genes showed a worse prognosis. Conclusions: We report the genomic enhancer signature associated with differential prognosis in HCC. Findings that cohere with oncofoetal reprogramming in HCC were underpinned by genome-wide enhancer rewiring. Our results present the epigenetic changes in HCC that offer the rational selection of epigenetic-driven gene targets for therapeutic intervention or disease prognostication in HCC. Impact and Implications: Lifestyle and environmental-related exposures are the important risk factors of hepatocellular carcinoma (HCC), suggesting that tumour-associated epigenetic dysregulations may significantly underpin HCC. We profiled tumour tissues and their matched normal from 30 patients with early-stage HCC to study the dysregulated epigenetic changes associated with HCC. By also analysing the patients' RNA-seq and clinical data, we found the signature genes - with epigenetic and transcriptomic dysregulation - associated with worse prognosis. Our findings suggest that systemic approaches are needed to consider the surrounding cellular environmental and epigenetic changes in HCC tumours.

Multi-region sampling with paired sample sequencing analyses reveals sub-groups of patients with novel patient-specific dysregulation in Hepatocellular Carcinoma.

BACKGROUND: Conventional differential expression (DE) testing compares the grouped mean value of tumour samples to the grouped mean value of the normal samples, and may miss out dysregulated genes in small subgroup of patients. This is especially so for highly heterogeneous cancer like Hepatocellular Carcinoma (HCC). METHODS: Using multi-region sampled RNA-seq data of 90 patients, we performed patient-specific differential expression testing, together with the patients' matched adjacent normal samples. RESULTS: Comparing the results from conventional DE analysis and patient-specific DE analyses, we show that the conventional DE analysis omits some genes due to high inter-individual variability present in both tumour and normal tissues. Dysregulated genes shared in small subgroup of patients were useful in stratifying patients, and presented differential prognosis. We also showed that the target genes of some of the current targeted agents used in HCC exhibited highly individualistic dysregulation pattern, which may explain the poor response rate. DISCUSSION/CONCLUSION: Our results highlight the importance of identifying patient-specific DE genes, with its potential to provide clinically valuable insights into patient subgroups for applications in precision medicine.

Dynamic phenotypic heterogeneity and the evolution of multiple RNA subtypes in hepatocellular carcinoma: the PLANET study.

Intra-tumor heterogeneity (ITH) is a key challenge in cancer treatment, but previous studies have focused mainly on the genomic alterations without exploring phenotypic (transcriptomic and immune) heterogeneity. Using one of the largest prospective surgical cohorts for hepatocellular carcinoma (HCC) with multi-region sampling, we sequenced whole genomes and paired transcriptomes from 67 HCC patients (331 samples). We found that while genomic ITH was rather constant across stages, phenotypic ITH had a very different trajectory and quickly diversified in stage II patients. Most strikingly, 30% of patients were found to contain more than one transcriptomic subtype within a single tumor. Such phenotypic ITH was found to be much more informative in predicting patient survival than genomic ITH and explains the poor efficacy of single-target systemic therapies in HCC. Taken together, we not only revealed an unprecedentedly dynamic landscape of phenotypic heterogeneity in HCC, but also highlighted the importance of studying phenotypic evolution across cancer types.

Resected pancreatic adenocarcinoma: An Asian institution's experience.

BACKGROUND: Pancreatic adenocarcinoma (PDAC) is highly lethal. Surgery offers the only chance of cure, but 5-year overall survival (OS) after surgical resection and adjuvant therapy remains dismal. Adjuvant trials were mostly conducted in the West enrolling fit patients. Applicability to a general population, especially Asia has not been described adequately. AIM: We aimed to evaluate the clinical outcomes, prognostic factors of survival, pattern, and timing of recurrence after curative resection in an Asian institution. METHODS AND RESULTS: The clinicopathologic and survival outcomes of 165 PDAC patients who underwent curative resection between 1998 and 2013 were reviewed retrospectively. Median age at surgery was 62.0 years. 55.2% were male, and 73.3% had tumors involving the head of pancreas. The median OS of the entire cohort was 19.7 months. Median OS of patients who received adjuvant chemotherapy was 23.8 months. Negative predictors of survival include lymph node ratio (LNR) of >0.3 (HR = 3.36, P = .001), tumor site involving the body or tail of pancreas (HR = 1.59, P = .046), presence of perineural invasion (PNI) (HR = 2.36, P = .018) and poorly differentiated/undifferentiated tumor grade (HR = 1.86, P = .058). The median time to recurrence was 8.87 months, with 66.1% and 81.2% of patients developing recurrence at 12 months and 24 months respectively. The most common site of recurrence was the liver. CONCLUSION: The survival of Asian patients with resected PDAC who received adjuvant chemotherapy is comparable to reported randomized trials. Clinical characteristics seem similar to Western patients. Hence, geographical locations may not be a necessary stratification factor in RCTs. Conversely, lymph node ratio and status of PNI ought to be incorporated.

Impact of Microsurgical Anastomosis of Hepatic Artery on Arterial Complications and Survival Outcomes After Liver Transplantation.

Hepatic artery (HA) complications after liver transplant (LT) can lead to biliary complications, graft failure, and mortality. Although microsurgery has been established to improve anastomotic outcomes, it prolongs surgical time and has not reached widespread adoption at all transplant centers. We investigated the incidences of arterial, biliary complications and outcomes after using microsurgery to anastomose HA during LT. Retrospective cohort of consecutive LT performed from 2006 to 2018 was reviewed for operative details and postoperative outcomes. Cox-regression models were used to investigate the relationship between variables and outcomes. Eighty (62.5%) LTs (Group 1) were performed without and compared with 48 (Group 2) with microsurgical anastomosis of HA. Both groups were comparable in terms of arterial and biliary anastomoses performed. Incidence of early HA thrombosis was similar (6.2% vs 2.1%, P = .28). Group 2 had lower incidence of short- and long-term arterial complications, especially amongst living donor liver transplantations (LDLT) (5.3% vs 35.0%, P = .022). On multivariate analysis, microsurgery was associated with lower risk (hazard ratio [HR] 0.09, 95% confidence interval [CI] 0.01-0.71) of, and LDLT had higher risk (HR 4.23, 95% CI 1.46-12.27) of arterial complications. Biliary complications were associated with LDLT (HR 3.91, 95% CI 1.30-11.71) and dual biliary anastomoses (HR 5.26, 95% CI 1.15-24.08) but not with occurrence of HA complications. Worse patient survival was associated with the occurrence of any HA complication (HR 4.11, 95% CI 1.78-9.48). Hepatic arterial complications can be reduced using microsurgical techniques for the anastomosis, resulting in improved patient survival outcomes after liver transplantation.

Comparison between long and short-term venous patencies after pancreatoduodenectomy or total pancreatectomy with portal/superior mesenteric vein resection stratified by reconstruction type.

BACKGROUND: Venous reconstruction has been recently demonstrated to be safe for tumours with invasion into portal vein and/or superior mesenteric vein. This study aims to compare the patency between various venous reconstructions. METHODS: This is retrospective study of 76 patients who underwent pancreaticoduodenectomy or total pancreatectomy with venous reconstruction from 2006 to 2018. Patient demographics, tumour histopathology, morbidity, mortality and patency were studied. Kaplan-Meier estimates were performed for primary venous patency. RESULTS: Sixty-two patients underwent pancreaticoduodenectomy and 14 underwent total pancreatectomy. Forty-seven, 19 and 10 patients underwent primary repair, end-to-end anastomosis and interposition graft respectively. Major morbidity (Clavien-Dindo >grade 2) and 30-day mortality were 14/76(18.4%) and 1/76(1.3%) respectively. There were 12(15.8%) venous occlusion including 4(5.3%) acute occlusions. Overall 6-month, 1-year and 2-year primary patency was 89.1%, 92.5% and 92.3% respectively. 1-year primary patency of primary repair was superior to end-to-end anastomosis and interposition graft (primary repair 100%, end-to-end anastomosis 81.8%, interposition graft 66.7%, p = 0.045). Pairwise comparison also demonstrated superior 1-year patency of primary repair (adjusted p = 0.037). There was no significant difference between the cumulative venous patency for each venous reconstruction method: primary repair 84±6%, end-to-end anastomosis 75±11% and interposition graft 76±15% (p = 0.561). CONCLUSION: 1-year primary venous patency of primary repair is superior to end-to-end anastomosis and interposition graft.

Pulmonary mucormycosis with diaphragm and liver involvement in a patient with haematopoietic stem cell transplant.

Pulmonary mucormycosis is a rare but life-threatening fungal infection. We report a post-haematopoietic stem cell transplant patient with pulmonary mucormycosis that extended to the diaphragm and subphrenic space. He underwent lung and diaphragm resection, debridement of liver capsule and diaphragm reconstruction using a pedicled latissimus dorsi flap. Following surgery, the patient remained well and has resumed his regular daily activities.

Circumportal pancreas: A report of two cases.

Circumportal pancreas (CP) is an unusual pancreatic anomaly occurring in 1.1 to 2.5% of individuals, where there is abnormal fusion of the uncinate process to the main pancreatic body occurring to the left of the portal vein-superior mesenteric vein (PV-SMV) junction. Since it was first described in 1987, there have only been a few reports documented in the literature. We recently encountered 2 such cases. Patient 1 was an 81-year-old man who presented with weight loss. Computed tomography (CT) scan revealed an atrophic pancreas with dilated pancreatic duct and a nodule at the head of pancreas, suspicious for a main-duct intraductal papillary mucinous neoplasm (IPMN) with malignant change. During surgery, we discovered that the uncinate process of the pancreas was completely wrapped around the SMV and fused with the main body, resulting in encasement of the PV-SMV junction. The patient also had a replaced right hepatic artery (RHA). Patient 2 was a 76-year-old man who complained of several weeks of abdominal discomfort. A CT scan showed a dilated common bile duct with a distal mass, worrisome for distal cholangiocarcinoma. Intra-operatively, he was similarly found to have union of the uncinate process of the pancreas with the main body occurring to the left of the PV-SMV confluence, with bilateral anomalous hepatic arteries. We present a brief review of the literature surrounding this condition. Although CP is usually asymptomatic, failure to recognize it may lead to serious consequences.

Clinicopathologic Characteristics and Survival of Patients with Gastroenteropancreatic Neuroendocrine Neoplasm in a Multi-Ethnic Asian Institution.

BACKGROUND: Epidemiological evidence suggests there are differences in gastroenteropancreatic neuroendocrine neoplasm (GEPNEN) among population groups. We aimed to contribute to the current evidence by evaluating the clinicopathological characteristics of GEPNEN in a multi-ethnic Asian group. MATERIALS AND METHODS: This was a retrospective chart review of patients diagnosed with GEPNEN at a tertiary medical institution at Singhealth Outram Campus, Singapore, between 1995 and 2015. RESULTS: Two hundred ninety-five patients were included in the evaluation, comprising Chinese (74.6%), Malay (4.4%), Indian (9.5%) and other (11.5%) ethnic backgrounds. The median age at diagnosis was 59 years; 52.5% were males. Distribution of disease stage at diagnosis was: localised (42.4%), regional (15.3%) and distant (38.0%). The three most common primary tumour sites were located in the pancreas (38.6%), rectum (19.7%) and stomach (9.5%), which varied significantly with ethnic background and age at diagnosis. Malay patients were younger (median 42 years) at diagnosis than Chinese (60 years). Patients with an appendiceal neuroendocrine neoplasm (NEN) (48 years) were younger compared to oesophageal NEN (66 years). Disease stage correlated with primary tumour site and grade (p < 0.001). Median overall survival (OS) for all GEPNEN was 10.2 years. Age at diagnosis, disease stage and grading were prognostic factors of OS in multivariable analyses. CONCLUSION: Our findings correspond with other studies that focus on GEPNEN incidences in Asian countries, with the pancreas, rectum and stomach being the most common primary tumour sites. Our findings suggest racial differences in primary tumour site and age at diagnosis. Further prospective population-based registries are required to understand these epidemiological differences.

Systematic review of the outcomes of surgical resection for intermediate and advanced Barcelona Clinic Liver Cancer stage hepatocellular carcinoma: A critical appraisal of the evidence.

AIM: To perform a systematic review to determine the survival outcomes after curative resection of intermediate and advanced hepatocellular carcinomas (HCC). METHODS: A systematic review of the published literature was performed using the PubMed database from 1st January 1999 to 31st Dec 2014 to identify studies that reported outcomes of liver resection as the primary curative treatment for Barcelona Clinic Liver Cancer (BCLC) stage B or C HCC. The primary end point was to determine the overall survival (OS) and disease free survival (DFS) of liver resection of HCC in BCLC stage B or C in patients with adequate liver reserve (i.e., Child's A or B status). The secondary end points were to assess the morbidity and mortality of liver resection in large HCC (defined as lesions larger than 10 cm in diameter) and to compare the OS and DFS after surgical resection of solitary vs multifocal HCC. RESULTS: We identified 74 articles which met the inclusion criteria and were analyzed in this systematic review. Analysis of the resection outcomes of the included studies were grouped according to (1) BCLC stage B or C HCC, (2) Size of HCC and (3) multifocal tumors. The median 5-year OS of BCLC stage B was 38.7% (range 10.0-57.0); while the median 5-year OS of BCLC stage C was 20.0% (range 0.0-42.0). The collective median 5-year OS of both stages was 27.9% (0.0-57.0). In examining the morbidity and mortality following liver resection in large HCC, the pooled RR for morbidity [RR (95%CI) = 1.00 (0.76-1.31)] and mortality [RR (95%CI) = 1.15 (0.73-1.80)] were not significant. Within the spectrum of BCLC B and C lesions, tumors greater than 10 cm were reported to have median 5-year OS of 33.0% and multifocal lesions 54.0%. CONCLUSION: Indication for surgical resection should be extended to BCLC stage B lesions in selected patients. Further studies are needed to stratify stage C lesions for resection.

Prospective study to determine early hypertrophy of the contra-lateral liver lobe after unilobar, Yttrium-90, selective internal radiation therapy in patients with hepatocellular carcinoma.

BACKGROUND: Liver resection is a major curative option in patients presenting with hepatocellular carcinoma. An inadequate functional liver remnant is a major limiting factor precluding liver resection. In recent years, hypertrophy of the functional liver remnant after selective internal radiation therapy hypertrophy has been observed, but the degree of hypertrophy in the early postselective internal radiation therapy period has not been well studied. METHODS: We conducted a prospective study on patients undergoing unilobar, Yttrium-90 selective internal radiation therapy for hepatocellular carcinoma to evaluate early hypertrophy at 4-6 weeks and 8-12 weeks after selective internal radiation therapy. RESULTS: In the study, 24 eligible patients were recruited and had serial volumetric measurements performed. The median age was 66 years (38-75 years). All patients were either Child-Pugh Class A or B, and 6/24 patients had documented, clinically relevant portal hypertension; 15 of the 24 patients were hepatitis B positive. At 4-6 weeks, modest hypertrophy was seen (median 3%; range -12 to 42%) and this increased at 8-12 weeks (median 9%; range -12 to 179%). No preprocedural factors predictive of hypertrophy were identified. CONCLUSION: Hypertrophy of the functional liver remnant after selective internal radiation therapy with Yttrium-90 occurred in a subset of patients but was modest and unpredictable in the early stages. Selective internal radiation therapy cannot be recommended as a standard treatment modality to induce early hypertrophy for patients with hepatocellular carcinoma. (Surgery 2017;160:XXX-XXX.).

Whole-Genome and Epigenomic Landscapes of Etiologically Distinct Subtypes of Cholangiocarcinoma.

Cholangiocarcinoma (CCA) is a hepatobiliary malignancy exhibiting high incidence in countries with endemic liver-fluke infection. We analyzed 489 CCAs from 10 countries, combining whole-genome (71 cases), targeted/exome, copy-number, gene expression, and DNA methylation information. Integrative clustering defined 4 CCA clusters-fluke-positive CCAs (clusters 1/2) are enriched in ERBB2 amplifications and TP53 mutations; conversely, fluke-negative CCAs (clusters 3/4) exhibit high copy-number alterations and PD-1/PD-L2 expression, or epigenetic mutations (IDH1/2, BAP1) and FGFR/PRKA-related gene rearrangements. Whole-genome analysis highlighted FGFR2 3' untranslated region deletion as a mechanism of FGFR2 upregulation. Integration of noncoding promoter mutations with protein-DNA binding profiles demonstrates pervasive modulation of H3K27me3-associated sites in CCA. Clusters 1 and 4 exhibit distinct DNA hypermethylation patterns targeting either CpG islands or shores-mutation signature and subclonality analysis suggests that these reflect different mutational pathways. Our results exemplify how genetics, epigenetics, and environmental carcinogens can interplay across different geographies to generate distinct molecular subtypes of cancer.Significance: Integrated whole-genome and epigenomic analysis of CCA on an international scale identifies new CCA driver genes, noncoding promoter mutations, and structural variants. CCA molecular landscapes differ radically by etiology, underscoring how distinct cancer subtypes in the same organ may arise through different extrinsic and intrinsic carcinogenic processes. Cancer Discov; 7(10); 1116-35. ©2017 AACR.This article is highlighted in the In This Issue feature, p. 1047.

Genomic and proteomic characterization of ARID1A chromatin remodeller in ampullary tumors.

AT rich interactive domain 1A (ARID1A) is one of the most commonly mutated genes in a broad variety of tumors. The mechanisms that involve ARID1A in ampullary cancer progression remains elusive. Here, we evaluated the frequency of ARID1A and KRAS mutations in ampullary adenomas and adenocarcinomas and in duodenal adenocarcinomas from two cohorts of patients from Singapore and Romania, correlated with clinical and pathological tumor features, and assessed the functional role of ARID1A. In the ampullary adenocarcinomas, the frequency of KRAS and ARID1A mutations was 34.7% and 8.2% respectively, with a loss or reduction of ARID1A protein in 17.2% of the cases. ARID1A mutational status was significantly correlated with ARID1A protein expression level (P=0.023). There was a significant difference in frequency of ARID1A mutation between Romania and Singapore (2.7% versus 25%, P=0.04), suggestive of different etiologies. One somatic mutation was detected in the ampullary adenoma group. In vitro studies indicated the tumor suppressive role of ARID1A. Our results warrant further investigation of this chromatin remodeller as a potential early biomarker of the disease, as well as identification of therapeutic targets in ARID1A mutated ampullary cancers.

The spatial organization of intra-tumour heterogeneity and evolutionary trajectories of metastases in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) has one of the poorest survival rates among cancers. Using multi-regional sampling of nine resected HCC with different aetiologies, here we construct phylogenetic relationships of these sectors, showing diverse levels of genetic sharing, spanning early to late diversification. Unlike the variegated pattern found in colorectal cancers, a large proportion of HCC display a clear isolation-by-distance pattern where spatially closer sectors are genetically more similar. Two resected intra-hepatic metastases showed genetic divergence occurring before and after primary tumour diversification, respectively. Metastatic tumours had much higher variability than their primary tumours, suggesting that intra-hepatic metastasis is accompanied by rapid diversification at the distant location. The presence of co-existing mutations offers the possibility of drug repositioning for HCC treatment. Taken together, these insights into intra-tumour heterogeneity allow for a comprehensive understanding of the evolutionary trajectories of HCC and suggest novel avenues for personalized therapy.

A case of small bowel metastasis from spinal Ewing sarcoma causing intussusception in an adult female.

BACKGROUND: Ewing sarcomas are highly aggressive malignant tumours occurring predominantly in the long bones of the extremities in children and young adults. About 20 % of patients will present with metastases at diagnosis with the commonest sites being the lungs, bone and bone marrow. Cases of primary small bowel Ewing sarcomas have been described but are nonetheless exceedingly rare, even more so cases of metastasis to the small bowel. CASE PRESENTATION: We describe a case of vertebral Ewing sarcoma in a 44 year-old female which metastasized to the jejunum causing intussusception. CONCLUSIONS: Ewing's sarcoma is highly aggressive and presence of metastases, overt or subclinical, is thought to be present in almost all patients at diagnosis. As evidenced by our patient, metastatic disease can progress rapidly to cause further complications and confer a poorer survival. The possibility of metastasis, no matter how rare or unlikely the site is, should be considered and actively investigated to expedite treatment of the primary disease.

Metastasectomy for metachronous pulmonary and hepatic metastases from nasopharyngeal carcinoma: Report of 6 cases and review of the literature.

BACKGROUND: Metastatic nasopharyngeal carcinoma (NPC) is commonly treated with palliative chemotherapy. The purpose of this study was to review the feasibility of metastasectomy for metachronous pulmonary and hepatic metastases from NPC. METHODS: We present 6 patients who developed metachronous metastases from NPC (4 patients with pulmonary metastases and 2 patients with hepatic metastases) and underwent curative resection. RESULTS: Four patients are still alive with no recurrence of NPC after metastasectomy. Two patients died with postoperative survival periods of 57 and 70 months and recurrence-free intervals of 14 and 39 months, respectively. CONCLUSION: Metastasectomy is a feasible option for the treatment of metachronous and resectable oligometastatic NPC to the lung and liver. Application of appropriate selection criteria would be required.

The Singapore Liver Cancer Recurrence (SLICER) Score for relapse prediction in patients with surgically resected hepatocellular carcinoma.

BACKGROUND AND AIMS: Surgery is the primary curative option in patients with hepatocellular carcinoma (HCC). Current prognostic models for HCC are developed on datasets of primarily patients with advanced cancer, and may be less relevant to resectable HCC. We developed a postoperative nomogram, the Singapore Liver Cancer Recurrence (SLICER) Score, to predict outcomes of HCC patients who have undergone surgical resection. METHODS: Records for 544 consecutive patients undergoing first-line curative surgery for HCC in one institution from 1992-2007 were reviewed, with 405 local patients selected for analysis. Freedom from relapse (FFR) was the primary outcome measure. An outcome-blinded modeling strategy including clustering, data reduction and transformation was used. We compared the performance of SLICER in estimating FFR with other HCC prognostic models using concordance-indices and likelihood analysis. RESULTS: A nomogram predicting FFR was developed, incorporating non-neoplastic liver cirrhosis, multifocality, preoperative alpha-fetoprotein level, Child-Pugh score, vascular invasion, tumor size, surgical margin and symptoms at presentation. Our nomogram outperformed other HCC prognostic models in predicting FFR by means of log-likelihood ratio statistics with good calibration demonstrated at 3 and 5 years post-resection and a concordance index of 0.69. Using decision curve analysis, SLICER also demonstrated superior net benefit at higher threshold probabilities. CONCLUSION: The SLICER score enables well-calibrated individualized predictions of relapse following curative HCC resection, and may represent a novel tool for biomarker research and individual counseling.

Preclinical evaluation of transcriptional targeting strategy for human hepatocellular carcinoma in an orthotopic xenograft mouse model.

Gene regulation of many key cell-cycle players in S-, G(2) phase, and mitosis results from transcriptional repression in their respective promoter regions during the G(0) and G(1) phases of cell cycle. Within these promoter regions are phylogenetically conserved sequences known as the cell-cycle-dependent element (CDE) and cell-cycle genes homology regions (CHR) sites. Thus, we hypothesize that transcriptional regulation of cell-cycle regulation via the CDE/CHR region together with liver-specific apolipoprotein E (apoE)-hAAT promoter could bring about a selective transgene expression in proliferating human hepatocellular carcinoma. We show that the newly generated vector AH-6CC-L2C could mediate hepatocyte-targeted luciferase gene expression in tumor cells and freshly isolated short-term hepatocellular carcinoma cultures from patient biopsy. In contrast, normal murine and human hepatocytes infected with AH-6CC-L2C expressed minimal or low luciferase activities. In the presence of prodrug 5-fluorocytosine (5-FC), AH-6CC-L2C effectively suppressed the growth of orthotopic hepatocellular carcinoma patient-derived xenograft mouse model via the expression of yeast cytosine deaminase (yCD) that converts 5-FC to anticancer metabolite 5-fluoruracil. More importantly, we show that combination treatment of AH-6CC-L2C with an EZH2 inhibitor, DZNep, that targets EpCAM-positive hepatocellular carcinoma, can bring about a greater therapeutic efficacy compared with a single treatment of virus or inhibitor. Our study showed that targeting proliferating human hepatocellular carcinoma cells through the transcriptional control of therapeutic gene could represent a feasible approach against hepatocellular carcinoma.

Intestinal torsion causing chylous ascites: a rare occurrence.

Intestinal torsion and chylous ascites are very rarely associated. We present the case of a 19-year-old man who presented with acute abdomen. Computed tomography of his abdomen showed features suggestive of intestinal torsion. Chylous ascites was incidentally discovered on exploratory laparotomy. The chylous fluid was drained, the small bowel detorted and the coloduodenal adhesion band taken down. The patient's retroperitoneum was explored to exclude occult masses and malformations of the lymphatics. Post surgery, the patient recovered uneventfully. In this case, we postulate that intestinal malrotation had caused the obstruction of the lymphatic flow from the mesenteric lymphatic channels, leading to the exudation of chyle, which then resulted in the accumulation of chylous fluid in the peritoneal cavity. It is important to exclude the more common causes of atraumatic chylous ascites, such as enlarged retroperitoneal lymph nodes or lymphatic malformations.