Search

Purpose; To determine the causes of benign hepaticojejunostomy strictures (BHSs) after pancreaticoduodenectomy (PD) and the outcome of endoscopic retrograde cholangiography (ERC) treatment for BHSs. Methods; A total of 175 patients who underwent PD between January 2013 and December 2020 and who were able to be followed up for at least 1 year were included. The preoperative data, operative outcomes, and postoperative course were compared between the BHS group and the group of patients who did not develop stenosis during follow-up (non-BHS group). The course of treatment in the BHS group was also tabulated. Results; Of the patients who underwent anastomosis of the common hepatic duct and jejunum, 13 required invasive treatment due to BHS (7.4%). Multivariate analysis in the BHS and non-BHS groups identified male sex (OR; 3.753, 95% CI; 1.029–18.003, P = 0.0448) and a preoperative bile duct diameter less than 8.8 mm (OR; 7.51, 95% CI; 1.75–52.40, P = 0.0053) as independent risk factors for the development of BHS. In the BHS group, all patients underwent ERC using enteroscopy. The success rate of the ERC approach to the bile duct was 92.3%. Plastic stents were inserted in 6 cases, and metallic stents were inserted in 3 cases. The median observation period since the last ERC was 17.9 months, and there was no recurrence of stenosis in any of the 13 patients. Conclusions; Patients with narrow bile ducts are at higher risk of BHS after PD. Recently, BHS after PD has been treated with ERC-related procedures, which may reduce the burden on patients.

KRAS mutation is a major driver of pancreatic carcinogenesis and will likely be a therapeutic target. Due to lack of sensitive assays for clinical samples of pancreatic cancer with low cellularity, KRAS mutations and their prognostic association have not been fully examined in large populations. In a multi-institutional cohort of 1162 pancreatic cancer patients with formalin-fixed paraffin-embedded tumor samples, we undertook droplet digital PCR (ddPCR) for KRAS codons 12/13/61. We examined detection rates of KRAS mutations by clinicopathological parameters and survival associations of KRAS mutation status. Multivariable hazard ratios (HRs) and 95% confidence intervals (CIs) for disease-free survival (DFS) and overall survival (OS) were computed using the Cox regression model with adjustment for potential confounders. KRAS mutations were detected in 1139 (98%) patients. The detection rate did not differ by age of tissue blocks, tumor cellularity, or receipt of neoadjuvant chemotherapy. KRAS mutations were not associated with DFS or OS (multivariable HR comparing KRAS-mutant to KRAS-wild-type tumors, 1.04 [95% CI, 0.62-1.75] and 1.05 [95% CI, 0.60-1.84], respectively). Among KRAS-mutant tumors, KRAS variant allele frequency (VAF) was inversely associated with DFS and OS with HRs per 20% VAF increase of 1.27 (95% CI, 1.13-1.42; p

Supplementary Figure 1 PDF file - 186K, Exogenous EGF rescued gemcitabine-induced apoptosis in vitro

Supplementary Table 1 PDF file - 108K, Adding erlotinib to gemcitabine synergistically inhibited the growth of mouse and human PDAC cells

Supplementary Figure 5 PDF file - 1755K, Gemcitabine-induced EGFR/ErbB2-MAPK signal activation was a common phenomenon in PDAC and lung cancer cells irrespective of KRAS mutation status and gemcitabine sensitivity.

Supplementary Figure 4 PDF file - 177K, The effect of erlotinib was mainly through the inhibition of MAPK signaling

Supplementary Materials PDF file - 91K, Supplementary Methods and Figure Legends

Supplementary Figure 3-1 PDF file - 354K, Gemcitabine-induced expression of EGFR ligands was dependent on active MAPK signaling in the PDAC cells

Supplementary Figure 3-2 PDF file - 172K, Gemcitabine-induced expression of EGFR ligands was dependent on active MAPK signaling in the lung cancer cells

Supplementary Figure 2 PDF file - 97K, MEK inhibition reduced the gemcitabine-induced activation of EGFR and ErbB2 in the PDAC cells

Background and aims: There is a lack of biliary epithelial molecular markers for primary sclerosing cholangitis (PSC). We analyzed candidates from disease susceptibility genes identified in recent genome-wide association studies. Methods: Expression was quantified using immunohistochemistry in biliary epithelia in liver biopsy samples from patients with PSC (N = 45) and controls (N = 12). Samples from patients with primary biliary cholangitis (PBC) were used as disease controls (N = 20). Results: The levels of hepatic expression of ATXN2, HHEX, PRDX5, MST1, and TNFRSF14 were significantly altered in the PSC group. We focused on the immune-related receptor, TNFRSF14. Immunohistochemistry revealed that TNFRSF14 positivity was significantly higher in biliary epithelia in the PSC group (96 %) than in the control (42 %) and PBC (55 %) groups. High expression of TNFRSF14 was observed only in patients with PSC. Moreover, the expression of LIGHT, which encodes a TNFRSF14-activating ligand, was increased in PSC liver. Immunohistochemistry showed that high expression of LIGHT was more common in PSC biliary epithelia (53 %) than in the PBC (15 %) or control (0 %) groups; moreover, it was positively associated with fibrotic progression. Conclusions: TNFRSF14 and LIGHT are attractive candidate markers for PSC.

The molecular subtypes of pancreatic cancer (PC), either classical/progenitor-like or basal/squamous-like, are currently a major topic of research because of their direct association with clinical outcomes. Some transcription factors (TFs) have been reported to be associated with these subtypes. However, the mechanisms by which these molecular signatures of PCs are established remain unknown. Epigenetic regulatory processes, supported by dynamic changes in the chromatin structure, are essential for transcriptional profiles. Previously, we reported the importance of open chromatin profiles in the biological features and transcriptional status of PCs. Here, we aimed to analyze the relationships between three-dimensional (3D) genome structures and the molecular subtypes of human PCs using Hi-C analysis. We observed a correlation of the specific elements of 3D genome modules, including compartments, topologically associating domains, and enhancer-promoter loops, with the expression of related genes. We focused on HNF1B, a TF that is implicated in the progenitor subtype. Forced expression of HNF1B in squamous-type PC organoids induced the upregulation and downregulation of genes associated with progenitor and squamous subtypes, respectively. Long-range genomic interactions induced by HNF1B were accompanied by compartment modulation and H3K27ac redistribution. We also found that these HNF1B-induced changes in subtype-related gene expression required an intrinsically disordered region, suggesting a possible involvement of phase separation in compartment modulation. Thus, mapping of 3D structural changes induced by TFs, such as HNF1B, may become a useful resource for further understanding the molecular features of PCs.

Ten‐eleven translocation 1 (TET1) is an essential methylcytosine dioxygenase of the DNA demethylation pathway. Despite its dysregulation being known to occur in human cancer, the role of TET1 remains poorly understood. In this study, we report that TET1 promotes cell growth in human liver cancer. The transcriptome analysis of 68 clinical liver samples revealed a subgroup of TET1‐upregulated hepatocellular carcinoma (HCC), demonstrating hepatoblast‐like gene expression signatures. We performed comprehensive cytosine methylation and hydroxymethylation (5‐hmC) profiling and found that 5‐hmC was aberrantly deposited preferentially in active enhancers. TET1 knockdown in hepatoma cell lines decreased hmC deposition with cell growth suppression. HMGA2 was highly expressed in a TET1high subgroup of HCC, associated with the hyperhydroxymethylation of its intronic region, marked as histone H3K4–monomethylated, where the H3K27‐acetylated active enhancer chromatin state induced interactions with its promoter. Collectively, our findings point to a novel type of epigenetic dysregulation, methylcytosine dioxygenase TET1, which promotes cell proliferation via the ectopic enhancer of its oncogenic targets, HMGA2, in hepatoblast‐like HCC., Ten‐eleven translocation 1 (TET1), a methylcytosine dioxygenase of the DNA demethylation pathway, is overexpressed in the subgroup of hepatocellular carcinoma with the hepatoblast‐like expression pattern. Comprehensive epigenome profilings revealed the ectopic enhancer activation of HMGA2 through cytosine hydroxymethylation, H3K27 acetylation, H3K4 monomethylation, and promoter‐enhancer interaction in a TET1‐dependent manner.

Accurate diagnosis of the disease extension of cholangiocarcinoma (CCA) is often difficult in clinical practice. The diagnostic yield of conventional pre-operative imaging or endoscopic procedures is sometimes insufficient for the evaluation of longitudinal spreading of CCA. Here we investigated the usefulness of 5-aminolevulinic acid (5-ALA) for the pre- or intra-operative diagnosis of CCA, using patient-derived organoids.Four CCA- and two adjacent tissue-derived organoids were established. After 5-ALA treatment, we assessed their photodynamic activity using fluorescence microscopy.CCA organoids established from different patients showed diverse morphology in contrast to monolayer structures of non-tumor organoids, and had the ability to form subcutaneous tumors in immunodeficient mice. CCA organoids demonstrated remarkably high photodynamic activity based on higher accumulation of protoporphyrin IX as a metabolite of 5-ALA compared to non-tumor organoids (40-71% vs. 4%, respectively). Importantly, cancer cell-specific high photodynamic activity distinguished the organoids originated from biliary stenotic lesions from those of non-stenotic lesions in a CCA patient. The high photodynamic activity did not depend on the expression profile of heme biosynthesis genes.Distinct 5-ALA-based photodynamic activity could have diagnostic potential for the discrimination of CCA from non-tumor tissues.

Purpose: The aim of this study was to evaluate the efficacy and tolerability of S-IROX and modified FOLFIRINOX (mFFX) after gemcitabine plus nab-paclitaxel for advanced pancreatic cancer (PC) in the real world setting. Methods: Consecutive patients receiving S-IROX or mFFX as a second-line chemotherapy for advanced PC refractory to gemcitabine plus nab-paclitaxel were retrospectively studied. Patients were treated every 2 weeks: S-1 40 mg/m2 was administered orally twice daily on days 1 to 7 in S-IROX and 5-fluorouracil 2400 mg/m2 was intravenously administered for 46 h without bolus infusion in mFFX, in addition to intravenous oxaliplatin 85 mg/m2 and irinotecan 150 mg/m2 on day 1 in both regimens. Results: Fifty-four patients with advanced PC who received S-IROX (n = 19) or mFFX (n = 35) were retrospectively studied. The disease control rate and response rate were 73.7% and 10.5% in the S-IROX group and 62.2% and 2.7% in the mFFX group, respectively. The median progression free survival (PFS) was 7.8 and 5.7 months in the S-IROX and mFFX groups (p = 0.24). The median overall survival (OS) was 14.2 and 11.5 months in the S-IROX and mFFX groups (p = 0.34). There were no significant differences in the incidences of grade 3–4 adverse effects. The subgroup analyses suggested S-IROX demonstrated favorable OS in patients with PFS ≥6 months of first-line gemcitabine plus nab-paclitaxel (p for interaction = 0.02). Conclusions: S-IROX and mFFX were similarly tolerable and effective as a second-line chemotherapy in patients with PC refractory to gemcitabine plus nab-paclitaxel.

Background/Aim: The entire mechanisms by which epigenetic modifiers contribute to the development of pancreatic cancer remain unknown. Although the histone methyltransferase G9a is a promising target in human cancers, its role in pancreatic carcinogenesis has been under-studied. The aim of the study was to examine the role of G9a in pancreatic carcinogenesis by a gene-targeting mouse model. Materials and Methods: We established pancreas-specific G9a(flox/flox )mice and crossed them with Ptf1a(Cre/); Kras(G12D/+ )(KC) mice, which spontaneously develop pancreatic cancer. The phenotypes of the resulting KC mice with G9a deletion were examined. We analyzed transcriptomic data by microarray and genome-wide chromatin accessibility by transposase-accessible chromatin using sequencing. We established pancreatic organoids from KC mice. Results: G9a deficiency impaired the progression of pancreatic intraepithelial neoplasia (PanIN) and prolonged the survival of KC mice. The number of phosphorylated Erk-positive cells and Dclk1-positive cells, which are reported to be essential for the progression of PanIN, were decreased by G9a deletion. UNC0638, an inhibitor of G9a, suppressed the growth of organoids and increased global chromatin accessibility, especially around the regions including the protein phosphatase 2A genes. Conclusion: Thus, our study suggested the functional interaction of G9a, Dclk1 and Mapk pathway in the Kras-driven pancreatic carcinogenesis. The inhibition of G9a may suppress the initiation of oncogenic Kras-driven pancreatic carcinogenesis.

Metabolism is a critical regulator of cell fate determination. Recently, the significance of metabolic reprogramming in environmental adaptation during tumorigenesis has attracted much attention in cancer research. Recurrent mutations in the isocitrate dehydrogenase (IDH) 1 or 2 genes have been identified in several cancers, including intrahepatic cholangiocarcinoma (ICC). Mutant IDHs convert α-ketoglutarate (α-KG) to 2-hydroxyglutarate (2-HG), which affects the activity of multiple α-KG-dependent dioxygenases including histone lysine demethylases. Although mutant IDH can be detected even in the early stages of neoplasia, how IDH mutations function as oncogenic drivers remains unclear. In this study, we aimed to address the biological effects of IDH1 mutation using intrahepatic biliary organoids (IBOs). We demonstrated that mutant IDH1 increased the formation of IBOs as well as accelerated glucose metabolism. Gene expression analysis and ChIP results revealed the upregulation of platelet isoform of phosphofructokinase-1 (PFKP), which is a rate-limiting glycolytic enzyme, through the alteration of histone modification. Knockdown of the Pfkp gene alleviated the mutant IDH1-induced increase in IBO formation. Notably, the high expression of PFKP was observed more frequently in patients with IDH-mutant ICC compared to in those with wild-type IDH (p

Three-dimensional (3D) chromatin structures connect genes to regulatory elements, thereby contributing to cell-type-specific gene regulation. However, its role in pancreatic cancer remains unclear. Inspired by our previous finding that open chromatin profiles analyzed by ATAC-seq well characterize the biological features and transcriptional status of pancreatic neoplasms, we hereby demonstrate the previously overlooked impact of 3D epigenetic regulation in pancreatic cancers. Through integrative analysis of Hi-C, ChIP-seq, and RNA-seq using patient-derived organoids, 3D genome modules, including compartments, topologically associating domains, and enhancer-promoter loops were found to play important roles in characterizing pancreatic tumors. Interestingly, intraductal papillary mucinous neoplasm (IPMN) lineages tended to have unique 3D chromatin structure profiles. We further found that transcriptional subtypes in pancreatic cancer, either classical/progenitor-like or basal/squamous-like, were largely underpinned by 3D structures. Compartment was responsible for supporting many subtype-specific genes, by synchronously activating genes that were in the vicinity, as represented by CYP2C family genes. Meanwhile, enhancer-promoter loop fine-tuned some key subtype genes, such as GATA6. By exploring the driving forces behind these 3D structures, we found that HNF1B, a transcription factor implicated in the progenitor subtype, was sufficient to induce subtype switch, together with their underlying 3D genome structure alterations. We demonstrate that HNF1B overexpression in squamous-type pancreatic cancer organoids induced the upregulation and downregulation of genes associated with the progenitor and squamous subtype, respectively. Mechanistically, these dynamic transcriptional and 3D structural modulation were accompanied by HNF1B-induced long-range genomic interactions and H3K27ac modification at HNF1B bound sites, implying HNF1B as a driving force. We also provide evidence suggesting that this HNF1B-induced subtype switch was mediated through the phase-separating property of HNF1B, which was enabled by its intrinsically disordered region (IDR). Induction of mutant HNF1B, whose IDR was either deleted (HNF1B-dIDR) or substituted by transcriptional phase-separation forming IDR from another peptide AKAP95 (HNF1B-AKAP95), showed that subtype switching effects of HNF1B were diminished by HNF1B-dIDR or recapitulated by HNF1B-AKAP95. Thus, HNF1B contributes to the transcriptional subtype formation in pancreatic cancers through its phase-separating structural ability. Collectively, the mapping of 3D structural changes induced by transcription factors, such as HNF1B, is useful for further understanding the features of pancreatic cancers. Our study may imply the potential of 3D structures to effectively suppress or unwind the malignant transformation process and to discover subtype-specific therapeutic targets. Citation Format: Hiroyuki Kato, Dosuke Iwadate, Keisuke Yamamoto, Hiroaki Fujiwara, Hideaki Ijichi, Mitsuhiro Fujishiro, Keisuke Tateishi. Hi-C analysis in patient-derived organoids reveals the impact of three-dimensional chromatin structures on pancreatic cancer transcriptional subtypes [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr A069.

Background & Aims Liver lobules are typically subdivided into 3 metabolic zones: zones 1, 2, and 3. However, the contribution of zonal differences in hepatocytes to liver regeneration, as well as to carcinogenic susceptibility, remains unclear. Methods We developed a new method for sustained genetic labelling of zone 3 hepatocytes and performed fate tracing to monitor these cells in multiple mouse liver tumour models. Results We first examined changes in the zonal distribution of the Wnt target gene Axin2 over time using Axin2-CreERT2;Rosa26-Lox-Stop-Lox-tdTomato mice (Axin2;tdTomato). We found that following tamoxifen administration at 3 weeks of age, approximately one-third of total hepatocytes that correspond to zone 3 were labelled in Axin2;tdTomato mice; the tdTomato+ cell distribution closely matched that of the zone 3 marker CYP2E1. Cell fate analysis revealed that zone 3 hepatocytes maintained their own lineage but rarely proliferated beyond their liver zonation during homoeostasis; this indicated that our protocol enabled persistent genetic labelling of zone 3 hepatocytes. Using this system, we found that zone 3 hepatocytes generally had high neoplastic potential, which was promoted by constitutive activation of Wnt/β-catenin signalling in the pericentral area. However, the frequency of zone 3 hepatocyte-derived tumours varied depending on the regeneration pattern of the liver parenchyma in response to liver injury. Notably, Axin2-expressing hepatocytes undergoing chronic liver injury significantly contributed to liver regeneration and possessed high neoplastic potential. Additionally, we revealed that the metabolic phenotypes of liver tumours were acquired during tumorigenesis, irrespective of their spatial origin. Conclusions Hepatocytes receiving Wnt/β-catenin signalling from their microenvironment have high neoplastic potential, and Wnt/β-catenin signalling is a potential drug target for the prevention of hepatocellular carcinoma. Lay summary Lineage tracing revealed that zone 3 hepatocytes residing in the pericentral niche have high neoplastic potential. Under chronic liver injury, hepatocytes receiving Wnt/β-catenin signalling broadly exist across all hepatic zones and significantly contribute to liver tumorigenesis as well as liver regeneration. Wnt/β-catenin signalling is a potential drug target for the prevention of hepatocellular carcinoma., Graphical abstract, Highlights • We developed a new method for sustained genetic labelling of Zone 3 hepatocytes. • Lineage tracing revealed that Zone 3 hepatocytes generally have high neoplastic potential. • The frequency of Zone 3 hepatocyte-derived tumours varied depending on the regeneration pattern of liver parenchyma. • Under chronic liver injury, hepatocytes receiving Wnt/β-catenin signalling significantly contributed to tumorigenesis. • Wnt/β-catenin signalling is a potential drug target for the prevention of HCC.

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with only a few effective therapeutic options. A characteristic feature of PDAC is its unique tumor microenvironment (TME), termed desmoplasia, which shows extensive fibrosis and extracellular matrix deposition, generating highly hypoxic and nutrient-deprived conditions within the tumor. To thrive in this harsh TME, PDAC undergoes extensive metabolic rewiring that includes the altered use of glucose and glutamine, constitutive activation of autophagy-lysosomal pathways, and nutrient acquisition from host cells in the TME. Notably, these properties support PDAC metabolism and mediate therapeutic resistance, including immune suppression. A deeper understanding of the unique metabolic properties of PDAC and its TME may aid in the development of novel therapeutic strategies against this deadly disease.

Head and neck squamous cell carcinoma (HNSCC) is a major malignancy worldwide. Ras overexpression in HNSCC is known to promote tumor cell growth; therefore, inhibition of Ras activation could lead to tumor growth suppression in HNSCC patients. Here, we investigated the effect of FTI-277, a farnesyl transferase inhibitor, and GGTI-287, a geranyltransferase 1 inhibitor, on the Ras signaling pathway in HNSCC cell lines-HEp-2 and HSC-3.Cell viability was analyzed using the trypan blue staining exclusion assay. The apoptosis of cells was assessed by flow cytometry and caspase activation analysis. The expression levels of proteins were examined using western blot analysis.FTI-277 and GGTI-287 induced cell death, enhanced caspase 3 activity, and increased the number of annexin V-positive cells in HEp-2 and HSC-3 cells. FTI-277 and GGTI-287 induced apoptosis in HSC-3 cells at much lower concentrations than that in HEp-2 cells. FTI-277 and GGTI-287 decreased the concentration of phosphorylated ERK1/2 and mTOR via membrane localization of Ras and enhanced Bim expression. Furthermore, FTI-277 and GGTI-287 induced cell death in v-H-Ras-transfected NIH3T3 (NW7) cells and not in empty vector-transfected NIH3T3 (NV20) cells.FTI-277 and GGTI-287 may be useful as potential therapeutic agents for treating HNSCC patients; moreover, farnesyl transferase and geranylgeranyltransferase 1 inhibitors can be further developed as anticancer agents.

Multiple myeloma (MM) is the second most common hematologic malignancy. In spite of the development of new therapeutic agents, MM remains incurable due to multidrug resistance (MDR) and the 5-year survival rate is approximately 50%. Thus, further study is needed to investigate the mechanism of MDR and improve MM prognosis. Heat shock protein 90 (HSP90) is a molecular chaperone that is responsible for the stability of a number of client proteins, most of which are involved in tumor progression. Therefore, HSP90 inhibitors represent potential new therapeutic agents for cancer. Furthermore, inhibition of HSP90 leads to degradation of client proteins, overcoming acquired anti-cancer drug resistance. In this study, we assessed the role of HSP90 in MDR using established melphalan-resistant MM cells. We found that expression of HSP90 was higher in melphalan-resistant MM cells than in parent cells and that HSP90 inhibitors KW-2478 and NUV-AUY922 restored drug sensitivity to the level observed in parent cells. Activation of the unfolded protein response is a hallmark of MM, and expression of endoplasmic reticulum stress signaling molecules is reduced in melphalan-resistant cells; however, KW-2478 did not affect endoplasmic reticulum stress signaling. We demonstrated that treatment with KW-2478 decreased expression of Src, a client of HSP90, and suppressed the activity of ERK, Akt, and NF-κB. Our findings indicate that inhibition of HSP90 results in suppression of Src and its downstream effectors, including ERK, Akt, and NF-κB, and therefore that HSP90 inhibitors could be useful for treatment of MDR MM.

Objectives A multivariate index calculated using plasma free amino acids (PFAA index) was reported as a diagnostic biomarker for pancreatic cancer (PaC). Although diabetes mellitus (DM) is expected to be an early diagnostic indicator of PaC, identifying the high-risk individuals among patients with DM is warranted. We evaluated the diagnostic yield of the PFAA index for PaC in patients with DM. Methods We compared the diagnostic yield of the PFAA index between individuals with and those without DM. Cases and controls were recruited prospectively, and controls were matched to cases at a 1:1 ratio for age, sex, and DM status. Results A total of 180 case–control pairs were included in the analysis. The prevalence of DM was 53.3%. The sensitivity of the PFAA index was 66.7% in cases with DM and 56.0% in those without DM (P = 0.14), and the specificity was 92.7% in controls with DM and 94.0% in those without DM (P = 0.95). Conclusions This matched case-control study revealed a comparable diagnostic yield of the PFAA index for PaC in individuals with and those without DM. The PFAA index can be used as a biomarker for further diagnostic imaging in selected patients with DM.

Purpose Our previous phase I trial suggested feasibility of addition of leucovorin (LV) to S-1 and gemcitabine therapy in advanced pancreatic cancer. The aim of this phase II trial was to assess the efficacy and toxicity of gemcitabine, S-1 and LV (GSL) combination therapy for advanced pancreatic cancer. Methods Chemotherapy-naïve patients with histologically or cytologically proven advanced pancreatic cancer were enrolled. Gemcitabine was administered at a dose of 1000 mg/m2 by 30 min infusion on days 1, S-1 40 mg/m2 orally twice daily and LV 25 mg orally twice daily on days 1 to 7 every 2 weeks. Primary end point was progression free survival (PFS). Results A total of 49 patients with advanced pancreatic cancer (19 locally advanced and 30 metastatic) were enrolled. Overall response rate and disease control rate were 32.7% and 87.8%. The median PFS and overall survival (OS) were 10.8 (95% confidence interval [CI], 7.4-13.5) and 20.7 (95% CI 13.0-NA) months with 1-year survival rate of 73.4%. Major Grade 3-4 toxicities were neutropenia (22.4%) and stomatitis (14.3%). No toxicity related death was observed. Conclusions In this single center, phase II trial, gemcitabine, S-1 and LV combination therapy was tolerable and can potentially be a treatment option for advanced pancreatic cancer.

While the significance of acquired genetic abnormalities in the initiation of hepatocellular carcinoma (HCC) has been established, the role of epigenetic modification remains unknown. Here we identified the pivotal role of histone methyltransferase G9a in the DNA damage-triggered initiation of HCC. Using liver-specific G9a-deficient (G9aΔHep) mice, we revealed that loss of G9a significantly attenuated liver tumor initiation caused by diethylnitrosamine (DEN). In addition, pharmacological inhibition of G9a attenuated the DEN-induced initiation of HCC. After treatment with DEN, while the induction of γH2AX and p53 were comparable in the G9aΔHep and wild-type livers, more apoptotic hepatocytes were detected in the G9aΔHep liver. Transcriptome analysis identified Bcl-G, a pro-apoptotic Bcl-2 family member, to be markedly upregulated in the G9aΔHep liver. In human cultured hepatoma cells, a G9a inhibitor, UNC0638, upregulated BCL-G expression and enhanced the apoptotic response after treatment with hydrogen peroxide or irradiation, suggesting an essential role of the G9a-Bcl-G axis in DNA damage response in hepatocytes. The proposed mechanism was that DNA damage stimuli recruited G9a to the p53-responsive element of the Bcl-G gene, resulting in the impaired enrichment of p53 to the region and the attenuation of Bcl-G expression. G9a deletion allowed the recruitment of p53 and upregulated Bcl-G expression. These results demonstrate that G9a allows DNA-damaged hepatocytes to escape p53-induced apoptosis by silencing Bcl-G, which may contribute to the tumor initiation. Therefore, G9a inhibition can be a novel preventive strategy for HCC.

Chemotherapy-induced peripheral neuropathy is a common factor in limiting therapy which can result in therapy cessation or dose reduction. Gabapentin, a calcium channel inhibitor, and duloxetine, a serotonin noradrenaline reuptake inhibitor, are used to treat a variety of pain conditions such as chronic low back pain, postherpetic neuralgia, and diabetic neuropathy. It has been reported that administration of gabapentin suppressed oxaliplatin- and paclitaxel-induced mechanical hyperalgesia in rats. Moreover, duloxetine has been shown to suppress oxaliplatin-induced cold allodynia in rats. However, the mechanisms by which these drugs prevent oxaliplatin- and paclitaxel-induced neuropathy remain unknown. Behavioral assays were performed using cold plate and the von Frey test. The expression levels of proteins were examined using western blot analysis. In this study, we investigated the mechanisms by which gabapentin and duloxetine prevent oxaliplatin- and paclitaxel-induced neuropathy in mice. We found that gabapentin and duloxetine prevented the development of oxaliplatin- and paclitaxel-induced cold and mechanical allodynia. In addition, our results revealed that gabapentin and duloxetine suppressed extracellular signal-regulated protein kinase 1/2 (ERK1/2) phosphorylation in the spinal cord of mice. Moreover, PD0325901 prevented the development of oxaliplatin- and paclitaxel-induced neuropathic-like pain behavior by inhibiting ERK1/2 activation in the spinal cord of mice. In summary, our findings suggest that gabapentin, duloxetine, and PD0325901 prevent the development of oxaliplatin- and paclitaxel-induced neuropathic-like pain behavior by inhibiting ERK1/2 phosphorylation in mice. Therefore, inhibiting ERK1/2 phosphorylation could be an effective preventive strategy against oxaliplatin- and paclitaxel-induced neuropathy.

The mechanism of H. pylori-induced atrophy and metaplasia has not been fully understood. Here, we demonstrate the novel role of Apoptosis signal-regulating kinase 1 (ASK1) and downstream MAPKs as a regulator of host immune responses and epithelial maintenance against H. pylori infection. ASK1 gene deficiency resulted in enhanced inflammation with numerous inflammatory cells including Gr-1+CD11b+ myeloid-derived suppressor cells (MDSCs) recruited into the infected stomach. Increase of IL-1β release from apoptotic macrophages and enhancement of TH1-polarized immune responses caused STAT1 and NF-κB activation in epithelial cells in ASK1 knockout mice. Dysregulated immune and epithelial activation in ASK1 knockout mice led to dramatic expansion of gastric progenitor cells and massive metaplasia development. Bone marrow transplantation experiments revealed that ASK1 in inflammatory cells is critical for inducing immune disorder and metaplastic changes in epithelium, while ASK1 in epithelial cells regulates cell proliferation in stem/progenitor zone without changes in inflammation and differentiation. These results suggest that H. pylori-induced immune cells may regulate epithelial homeostasis and cell fate as an inflammatory niche via ASK1 signaling.

Background: ABO blood group has been associated with risks of various malignancies, including pancreatic cancer. No study has evaluated the association of ABO blood group with incidence of pancreatic carcinogenesis during follow-up of patients with intraductal papillary mucinous neoplasms (IPMN). Methods: Among 3,164 patients diagnosed with pancreatic cysts at the University of Tokyo (Tokyo, Japan) from 1994 through 2019, we identified 1,815 patients with IPMN with available data on ABO blood group. We studied the association of ABO blood group with incidence of pancreatic carcinoma, overall and by carcinoma types [IPMN-derived carcinoma or concomitant pancreatic ductal adenocarcinoma (PDAC)]. Utilizing competing-risks proportional hazards models, we estimated subdistribution hazard ratios (SHR) for incidence of pancreatic carcinoma with adjustment for potential confounders, including cyst characteristics. Results: During 11,518 person-years of follow-up, we identified 97 patients diagnosed with pancreatic carcinoma (53 with IPMN-derived carcinoma and 44 with concomitant PDAC). Compared with patients with blood group O, patients with blood groups A, B, and AB had multivariable SHRs (95% confidence intervals) for pancreatic carcinoma of 2.25 (1.25–4.07; P = 0.007), 2.09 (1.08–4.05; P = 0.028), and 1.17 (0.43–3.19; P = 0.76), respectively. We observed no differential association of ABO blood group with pancreatic carcinoma incidence by carcinoma types. Conclusions: In this large long-term study, patients with IPMN with blood group A or B appeared to be at higher risk of pancreatic carcinoma compared with those with blood group O. Impact: ABO blood group can be a biomarker for pancreatic cancer risk among patients with IPMNs.

Chromatin architecture governs cell lineages by regulating the specific gene expression; however, its role in the diversity of cancer development remains unknown. Among pancreatic cancers, pancreatic ductal adenocarcinoma (PDAC) and intraductal papillary mucinous neoplasms (IPMN) with an associated invasive carcinoma (IPMNinv) arise from 2 distinct precursors, and their fundamental differences remain obscure. Here, we aimed to assess the difference of chromatin architecture regulating the transcriptional signatures or biological features in pancreatic cancers.We established 28 human organoids from distinct subtypes of pancreatic tumors, including IPMN, IPMNinv, and PDAC. We performed exome sequencing (seq), RNA-seq, assay for transposase-accessible chromatin-seq, chromatin immunoprecipitation-seq, high-throughput chromosome conformation capture, and phenotypic analyses with short hairpin RNA or clustered regularly interspaced short palindromic repeats interference.Established organoids successfully reproduced the histology of primary tumors. IPMN and IPMNinv organoids harbored GNAS, RNF43, or KLF4 mutations and showed the distinct expression profiles compared with PDAC. Chromatin accessibility profiles revealed the gain of stomach-specific open regions in IPMN and the pattern of diverse gastrointestinal tissues in IPMNinv. In contrast, PDAC presented an impressive loss of accessible regions compared with normal pancreatic ducts. Transcription factor footprint analysis and functional assays identified that MNX1 and HNF1B were biologically indispensable for IPMN lineages. The upregulation of MNX1 was specifically marked in the human IPMN lineage tissues. The MNX1-HNF1B axis governed a set of genes, including MYC, SOX9, and OLFM4, which are known to be essential for gastrointestinal stem cells. High-throughput chromosome conformation capture analysis suggested the HNF1B target genes to be 3-dimensionally connected in the genome of IPMNinv.Our organoid analyses identified the MNX1-HNF1B axis to be biologically significant in IPMN lineages.

Peribiliary glands (PBGs), clusters of epithelial cells residing in the submucosal compartment of extrahepatic bile ducts, have been suggested as biliary epithelial stem/progenitor cell niche; however, evidence to support this claim is limited because of a lack of PBG-specific markers. We therefore sought to identify PBG-specific markers to investigate the potential role of PBGs as stem/progenitor cell niches, as well as an origin of cancer.We examined the expression pattern of the Wnt target gene Axin2 in extrahepatic bile ducts. We then applied lineage tracing to investigate whether Axin2-expressing cells from PBGs contribute to biliary regeneration and carcinogenesis using Axin2-CreWnt signaling activation, marked by Axin2, was limited to PBGs located in the periampullary region. Lineage tracing showed that Axin2-expressing periampullary PBG cells are capable of self-renewal and supplying new biliary epithelial cells (BECs) to the luminal surface. Additionally, the expression pattern of Axin2 and the mature ductal cell marker CK19 were mutually exclusive in periampullary region, and fate tracing of CK19A specific cell population receiving Wnt-activating signal in periampullary PBGs functions as biliary epithelial stem/progenitor cells and also the cellular origin of ampullary carcinoma.