Roberts, Lewis R

Abstract Background and Aims: Cholangiocarcinoma (CCA) is the second most common primary hepatic malignancy. Based on its anatomical location, CCA can be divided into intrahepatic (iCCA) or extrahepatic (eCCA), with differences in etiology, pathogenesis and clinical management. Few studies have focused on the molecular profiling of eCCA as a single entity, even though it accounts for the most prevalent subtype. Thus, integrative genomic analysis of eCCA would provide critical understanding for the biological traits of this tumor. Methods: 189 FFPE primary eCCA treated by resection were collected at seven international centers from 1995 to 2015. Median survival of the cohort was of 48.5mo. Whole gene-expression profiles were submitted to unsupervised clustering by NMF consensus. Clusters were characterized by Gene Set Enrichment Analysis and Ingenuity Pathway Analysis. Activation of signaling pathways (mTOR/pRPS6 and HER2) was assessed by immunohistochemistry (IHC). Molecular features were correlated with clinico-pathological data. Screening of most prevalent somatic mutations and copy number aberrations is ongoing. Results: We have identified four distinct molecular subtypes of eCCA (cophenetic coefficient=0.995). Tumors classified within the metabolic class (18.7%) were enriched by gene signatures defining bile and fatty acid metabolism (p<0.001) and presented overexpression of classic hepatocyte markers, with HNF4A as the major activated upstream transcription factor (p<0.001). The proliferation class (22.5%) was associated with papillary histology (p=0.004) and presented enrichment of MYC (p<0.001), mTOR (p=0.018) and HER2 (p=0.024) signaling. Subclass mapping identified similarity with the iCCA proliferation subclass (p<0.001). The mesenchymal class (47.3%) was associated with signatures defining epithelial-mesenchymal transition (p<0.001) as well as stromal activation (p<0.001), which was in accordance with TGFB1 as the major activated upstream regulator (p<0.001) and the presence of higher desmoplasia at pathological analysis (p=0.046). Moreover, mesenchymal tumors were significantly associated with poor prognosis in terms of OS (33.2 vs 55.5mo, HR=2.02, p=0.022). Finally, tumors classified as immune class (11.5%) presented increased tumor-infiltrating lymphocytes (p=0.001) and were characterized by enrichment of IFNγ signaling (p<0.001). Conclusions: Transcriptome-based subtyping of eCCA identifies four distinct molecular classes (metabolic, proliferation, mesenchymal and immune) that correlate with clinical-pathological characteristics. These findings enhance the opportunities for therapeutic development in this tumor with dismal prognosis and without approved molecular treatments. Citation Format: Robert Montal, Wei Qiang Leow, Carla Montironi, Laia Bassaganyas, Agrin Moeini, Daniela Sia, Roser Pinyol, Laia Cabellos, Judit Peix, Miho Maeda, Carlos Villacorta, Parissa Tabrizian, Christine Sempoux, Beatriz Minguez, Tim Pawlik, Ismail Labgaa, Lewis Roberts, Manel Sole, Maria Isabel Fiel, Swan Thung, Sasan Roayaie, Augusto Villanueva, Myron Schwartz, Josep Maria Llovet. Integrative molecular classification of extrahepatic cholangiocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4618.

Objective: To evaluate the effect of hepatic steatosis on LI-RADS® major features at MRI in patients with non-alcoholic fatty liver disease (NAFLD)-associated hepatocellular carcinoma (HCC). Methods: HCC and liver parenchyma features at MRI from 48 consecutive patients with NAFLD and histology proven HCC (mean ± SD; 4.5 ± 3.4 cm) were independently reviewed by three radiologists. Inter-rater agreement was determined by prevalence/bias-adjusted kappa. Hepatic fat signal fraction (FS%) was independently calculated. HCC features were compared by FS% at MRI using logistic regression analysis and histologic steatosis grade using Cochran-Armitage test for trend, stratified by cirrhotic liver morphology or histologic fibrosis stage. Receiver operating characteristic curves were generated to determine the sensitivity and specificity for major HCC features by FS%. Results: Major HCC features included arterial phase hyperenhancement (APHE) in 45 (93%), portal venous phase washout (PVWO) in 30 (63%), delayed phase washout (DPWO) in 38 (79%) and enhancing “capsule” in 34 (71%). Cirrhotic morphology was present in 22 (46%). Inter-rater agreement was 0.75 for APHE, 0.42–0.58 for PVWO, 0.58–0.71 for DPWO and 0.38–0.67 for enhancing “capsule”. There was an 18%, 14% and 22% increase in the odds of absent PVWO, DPWO and capsule appearance for every 1% increase in hepatic FS% in patients with non-cirrhotic liver morphology (p = 0.011, 0.040 and 0.029, respectively). Hepatic FS% ≥ 14.8% had a sensitivity and specificity of 64 and 100% for absent PVWO and 71 and 90% for absent DPWO in patients with non-cirrhotic liver morphology. Conclusion: Absent washout and capsule appearance are associated with increasing hepatic steatosis in patients with non-cirrhotic, NAFLD-associated HCC. Advances in knowledge: In patients with non-cirrhotic, non-alcoholic fatty liver disease (NAFLD)-associated hepatocellular carcinoma (HCC), absent HCC washout and capsule appearance are associated with increasing hepatic steatosis, thereby potentially impacting the noninvasive imaging diagnosis of HCC in these patients. Lack of washout or capsule appearance in steatotic livers at MRI may require alternative criteria for the diagnosis of HCC in patients with non-cirrhotic NAFLD.

The purposes of this study were to test the hypothesis that heat stress and hepatic thermal ablation induce nerve growth factor inducible (VGF) and to determine intrahepatic versus systemic VGF expression induced by thermal ablation in vivo and in patients. Hepatocytes and HCC cells were subjected to moderate (45°C) or physiologic (37°C) heat stress for 10 min and assessed for VGF expression at 0‐72 h post-heat stress ( n ≥ 3 experiments). Orthotopic N1S1 HCC-bearing rats were randomized to sham or laser thermal ablation (3 W × 90 s), and liver/serum was harvested at 0‐7 days postablation for analysis of VGF expression ( n ≥ 6 per group). Serum was collected from patients undergoing thermal ablation for HCC ( n = 16) at baseline, 3‐6, and 18‐24 h postablation and analyzed for VGF expression. Data were analyzed using ordinary or repeated-measures one-way analysis of variance and post hoc pairwise comparison with Dunnett’s test. Moderate heat stress induced time-dependent VGF mRNA (3- to 15-fold; p < 0.04) and protein expression and secretion (3.1- to 3.3-fold; p < 0.05). Thermal ablation induced VGF expression at the hepatic ablation margin at 1 and 3 days postablation but not remote from the ablation zone or distant intrahepatic lobe. There was no detectable serum VGF following hepatic thermal ablation in rats and no increase in serum VGF following HCC thermal ablation in patients at 3‐6 and 18‐24 h postablation compared to baseline (0.71- and 0.63-fold; p = 0.27 and p = 0.16, respectively). Moderate heat stress induces expression and secretion of VGF in HCC cells and hepatocytes in vitro, and thermal ablation induces local intrahepatic but not distant intrahepatic or systemic VGF expression in vivo.

Abstract Researchers hypothesized that telomere shortening facilitates carcinogenesis. Previous studies found inconsistent associations between blood leukocyte telomere length (LTL) and cancer. Epigenetic reprogramming of telomere maintenance mechanisms may help explain this inconsistency. We examined associations between DNA methylation in telomere-related genes (TRG) and cancer. We analyzed 475 participants providing 889 samples 1 to 3 times (median follow-up, 10.1 years) from 1999 to 2013 in the Normative Aging Study. All participants were cancer-free at each visit and blood leukocytes profiled using the Illumina 450K array. Of 121 participants who developed cancer, 34 had prostate cancer, 10 melanoma, 34 unknown skin malignancies, and 43 another cancer. We examined 2,651 CpGs from 80 TRGs and applied a combination of Cox and mixed models to identify CpGs prospectively associated with cancer (at FDR &lt; 0.05). We also explored trajectories of DNA methylation, logistic regression stratified by time to diagnosis/censoring, and cross-sectional models of LTL at first blood draw. We identified 30 CpGs on 23 TRGs whose methylation was positively associated with cancer incidence (β = 1.0–6.93) and one protective CpG in MAD1L1 (β = −0.65), of which 87% were located in TRG promoters. Methylation trajectories of 21 CpGs increased in cancer cases relative to controls; at 4 to 8 years prediagnosis/censoring, 17 CpGs were positively associated with cancer. Three CpGs were cross-sectionally associated with LTL. TRG methylation may be a mechanism through which LTL dynamics reflect cancer risk. Future research should confirm these findings and explore potential mechanisms underlying these findings, including telomere maintenance and DNA repair dysfunction. Cancer Prev Res; 11(8); 511–22. ©2018 AACR.

SummaryBackgroundHepatitis B virus (HBV) is the leading cause of hepatocellular carcinoma (HCC) worldwide. It remains incompletely understood in the real world how anti‐viral therapy affects survival after HCC diagnosis.MethodsThis was an international multicentre cohort study of 2518 HBV‐related HCC cases diagnosed between 2000 and 2015. Cox proportional hazards models were utilised to estimate hazard ratios (HR) with 95% (CI) for anti‐viral therapy and cirrhosis on patients' risk of death.ResultsApproximately, 48% of patients received anti‐viral therapy at any time, but only 17% were on therapy at HCC diagnosis (38% at US centres, 11% at Asian centres). Anti‐viral therapy would have been indicated for >60% of the patients not on anti‐viral therapy based on American criteria. Patients with cirrhosis had lower 5‐year survival (34% vs 46%; P < 0.001) while patients receiving anti‐viral therapy had increased 5‐year survival compared to untreated patients (42% vs 25% with cirrhosis and 58% vs 36% without cirrhosis; P < 0.001 for both). Similar findings were seen for other patient subgroups by cancer stages and cancer treatment types. Anti‐viral therapy was associated with a decrease in risk of death, whether started before or after HCC diagnosis (adjusted HR 0.62 and 0.79, respectively; P < 0.001).ConclusionsAnti‐viral therapy improved overall survival in patients with HBV‐related HCC across cancer stages and treatment types but was underutilised at both US and Asia centres. Expanded use of anti‐viral therapy in HBV‐related HCC and better linkage‐to‐care for HBV patients are needed.

Intrahepatic cholangiocarcinoma remains a highly heterogeneous malignancy that has eluded effective patient stratification to date. The extent to which such heterogeneity can be influenced by individual driver mutations remains to be evaluated. Here, we analyzed genomic (whole‐exome sequencing, targeted exome sequencing) and epigenomic data from 496 patients and used the three most recurrently mutated genes to stratify patients ( IDH , KRAS , TP53 , “undetermined”). Using this molecular dissection approach, each subgroup was determined to possess unique mutational signature preferences, comutation profiles, and enriched pathways. High‐throughput drug repositioning in seven patient‐matched cell lines, chosen to reflect the genetic alterations specific for each patient group, confirmed in silico predictions of subgroup‐specific vulnerabilities linked to enriched pathways. Intriguingly, patients lacking all three mutations (“undetermined”) harbored the most extensive structural alterations, while isocitrate dehydrogenase mutant tumors displayed the most extensive DNA methylome dysregulation, consistent with previous findings. Conclusion : Stratification of intrahepatic cholangiocarcinoma patients based on occurrence of mutations in three classifier genes ( IDH , KRAS , TP53 ) revealed unique oncogenic programs (mutational, structural, epimutational) that influence pharmacologic response in drug repositioning protocols; this genome dissection approach highlights the potential of individual mutations to induce extensive molecular heterogeneity and could facilitate advancement of therapeutic response in this dismal disease. (H epatology 2018).

Hepatocytes do not express Bcl-2, a repressor of apoptosis. In contrast, cholangiocytes, which are in direct contact with bile, do express Bcl-2. Because cholestasis results in the retention of bile within hepatocytes, we reasoned cholestasis may induce hepatocellular expression of Bcl-2. Thus our aim was to determine whether hepatocytes express Bcl-2 or alter expression of other Bcl-2 family members in cholestasis using the bile duct-ligated (BDL) rat as a model of cholestasis. De novo Bcl-2 expression was observed in hepatocytes of BDL rats assessed by reverse transcriptase-polymerase chain reaction and immunoblot analysis. Immunohistochemistry demonstrated that Bcl-2 expression in hepatocytes was greater in periportal hepatocytes than pericentral hepatocytes. Expression of Bcl-x (an antiapoptotic Bcl-2 family protein) was not altered by bile duct ligation, whereas expression of Bax (a proapoptotic Bcl-2 family protein) increased slightly as determined by Northern and Western blot analyses. Bcl-2-positive hepatocytes isolated from BDL rats were resistant to induction of apoptosis by 50 microM glycochenodeoxycholate. Our results demonstrate, for the first time, expression of Bcl-2 by hepatocytes during cholestasis. We suggest that hepatocellular expression of Bcl-2 during cholestasis is an adaptive phenomenon to resist apoptosis by toxic bile salts.

Background: The human sulfatase 1 (SULF1) and sulfatase 2 (SULF2) genes modulate cell signaling and homeostasis in many tissues. Gene expression analyses have implicated SULF2 in disease pathogenesis, including Alzheimer’s disease (AD), but changes in brain SULF2 expression have not been directly established. Objective: To investigate the expression of SULF1 and SULF2 in brain tissues from AD cases and cognitively normal controls. Methods: Autopsy tissue from AD cases ( n = 20) and age-and gender-matched cognitively normal controls ( n = 20) were identified from the Mayo Clinic Alzheimer’s Disease Patient Registry neuropathology database. Tissue slides were stained for SULF1 and SULF2 protein expression in the hippocampus and frontal lobe and an expression score computed from the proportion of cells stained and the intensity of staining (range 0 [no expression] to 9 [marked expression]). Results: SULF2 expression was reduced in AD cases. Compared to cognitively normal controls, SULF2 expression in AD cases was significantly decreased in the hippocampal Cornu Ammonis (CA) (mean score of 6.5 in cases versus 8.3 in controls; p = 0.003), in the gray matter of the parahippocampal gyrus (5.6 in cases versus 7.6 in controls; p = 0.003), and in the frontal lobe gray matter (5.4 in cases versus 7.4 in controls; p = 0.002). There was no difference in SULF1 expression in the hippocampus or frontal lobe of AD cases and controls. As expected there were no differences in SULF1 or SULF2 expression in white matter in AD cases compared to cognitively normal controls. Conclusion: Decreased SULF2 in specific regions of the brain occurs in AD.