The Effect of Renin-Angiotensin System Inhibitors in Patients Undergoing Pancreatic Cancer Resection.

OBJECTIVES: The local renin-angiotensin system promotes angiogenesis and proliferation via vascular endothelial growth factor or epidermal growth factor receptor expression. In this study, we aimed to evaluate the impact of angiotensin system inhibitors (ASIs) on long-term outcomes in patients undergoing surgical resection of pancreatic ductal adenocarcinoma (PDAC). METHODS: A single institutional retrospective analysis was performed using the medical records of patients who underwent pancreatic resection with curative intent for PDAC between January 2005 and December 2018. Patient characteristics and surgical outcomes were compared between patients taking ASIs and those who are not. RESULTS: A total of 272 patients were included in the study and classified into the ASI group (n = 121) and the non-ASI group (n = 151). The median overall survival times in the ASI group and non-ASI group were 38.0 and 34.0 months ( P = 0.250), and the median recurrence-free survival times were 24.0 and 15.0 months ( P = 0.025), respectively. Multivariate analysis for recurrence-free survival identified the use of ASIs ( P = 0.020), CA19-9 level >500 IU/L ( P = 0.010), positive lymph node metastasis ( P < 0.001), and no adjuvant chemotherapy ( P < 0.001) as independent prognostic factors. CONCLUSIONS: The use of ASI may improve long-term outcomes after surgery for PDAC.

Effects of tramadol via a µ-opioid receptor on pancreatic ductal adenocarcinoma in vitro and in vivo.

INTRODUCTION: Tramadol, a weak opioid anesthetic, is used for pain management in patients with cancer, but the effects of tramadol on cancer via µ-opioid receptor are still unknown. We assessed the effects of tramadol on pancreatic ductal adenocarcinoma using transgenic mice (LSL-KrasG12D/+; Trp53flox/flox; Pdx-1cre/+ ). METHODS: Six-week-old transgenic mice were orally administered 10 mg/kg/day tramadol (n=12), 10 mg/kg/day tramadol and 1 mg/kg/day naltrexone (n=9), or vehicle water (n=14) until the humane endpoint. Cancer-related pain and plasma cytokine levels were assessed by the mouse grimace scale and cytokine array, respectively. Tumor status was determined histopathologically. Tramadol's effects on proliferation and invasion in pancreatic ductal adenocarcinoma cell lines were studied in vitro. RESULTS: Tramadol with/without naltrexone improved mouse grimace scale scores while decreasing inflammatory cytokines such as tumor necrosis factor-α and interleukin-6. Proliferative Ki-67 and cyclins decreased by tramadol, while local M1-like tumor-associated macrophages increased by tramadol, which was blocked by naltrexone. Meanwhile, tramadol with/without naltrexone reduced juxta-tumoral cancer-associated fibroblasts and M2-like tumor-associated macrophages. Tumor-associated neutrophils, natural killers, and cytotoxic T cells were not altered. Tramadol decreased the proliferative and invasive potentials of pancreatic ductal adenocarcinoma cell lines via decreasing cyclins/cyclin-dependent kinases, which was partially reversed by naltrexone. CONCLUSIONS: These findings imply that tramadol might be a useful anesthetic for pancreatic ductal adenocarcinoma: inhibiting the proliferation and invasion along with increasing antitumor M1-like tumor-associated macrophages via the µ-opioid receptor, while improving cancer-associated pain possibly through the antitumor effects with the decrease of inflammatory cytokines.

Significance of Tumor Microenvironment for Regulating Pancreatic Cancer.

Pancreatic cancer is the most lethal common cancer in the world [...].

Combination of serum human satellite RNA and miR-21-5p levels as a biomarker for pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) has a poor prognosis due to the difficulty of its diagnosis. Because human satellite II (HSATII) RNA, a satellite repeat RNA, is highly and specifically expressed in human PDAC, the serum HSATII RNA level may be a biomarker of PDAC. To measure the serum HSATII RNA level with high sensitivity and reproducibility, we previously developed a convenient method, tandem repeat amplification by nuclease protection (TRAP) combined with droplet digital PCR (ddPCR). Here, we refined the original method by simultaneously measuring the serum miR-21-5p level to enhance the detection of PDAC. The resulting PDAC-Index, constructed using serum HSATII RNA and miR-21-5p levels, discriminated patients with PDAC with high accuracy. We verified the clinical usefulness of the PDAC-Index as a supportive test in difficult-to-diagnose cases. The PDAC-Index has satisfactory diagnostic performance and may routinely be applied for detecting PDAC.

Clinical Outcomes of Intraductal Papillary Mucinous Neoplasms With Dilatation of the Main Pancreatic Duct.

BACKGROUND & AIMS: Dilatation of the main pancreatic duct (MPD) has been a surgical indication for intraductal papillary mucinous neoplasms (IPMNs). Few studies have investigated long-term outcomes of IPMNs with MPD dilatation. METHODS: Among 3610 patients diagnosed with pancreatic cysts between 1994 and 2021, we identified 2829 IPMN patients, including 282 patients with MPD ≥5 mm, and examined short-term (≤6 months) and long-term risks of pancreatic carcinoma. Utilizing competing risks proportional hazards models, we estimated subdistribution hazard ratios for incidence of pancreatic carcinoma with adjustment for potential confounders. RESULTS: In analyses of short-term outcomes of the 282 patients with MPD dilatation, 72 (26%) patients were diagnosed with pancreatic carcinoma based on surgical or nonsurgical exploration. During long-term follow-up of 168 patients, we documented 24 (14%) patients diagnosed with pancreatic carcinoma (18 with IPMN-derived carcinoma and 6 with concomitant ductal adenocarcinoma). The patients with the MPD = 5-9.9 mm had cumulative incidence rates of pancreatic carcinoma diagnosis of 8.1% (95% confidence interval [CI], 4.3%-13.5%) and 10.0% (95% CI, 5.5%-15.9%) at 2 and 5 years, respectively; and the patients with the MPD ≥10 mm had the corresponding rates of 16.0% (95% CI, 3.6-36.5%) and 33.3% (95% CI, 10.3%-58.8%). The multivariable subdistribution hazard ratios were 2.78 (95% CI, 1.57-4.90) and 7.00 (95% CI, 2.58-19.0) for the MPD = 5-9.9 mm and ≥10 mm (vs <5 mm), respectively. CONCLUSIONS: IPMNs with MPD dilatation at baseline were associated with higher prevalence and incidence of pancreatic carcinoma compared with IPMNs with no MPD dilatation.

Overcoming resistance of stroma-rich pancreatic cancer with focal adhesion kinase inhibitor combined with G47Δ and immune checkpoint inhibitors.

Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease known for its dense tumor stroma. Focal adhesion kinase inhibitor (FAKi), a non-receptor type tyrosine kinase inhibitor, reduces the tumor stroma. G47Δ, a third-generation oncolytic herpes simplex virus type 1, destroys tumor cells selectively and induces antitumor immune responses. This study evaluates the efficacy of FAKi and G47Δ in PDAC models in combination with or without immune checkpoint inhibitors. G47Δ was effective in human PDAC cell lines in vitro and in subcutaneous as well as orthotopic tumor models. Transgenic mouse-derived #146 cells were used to generate subcutaneous PDAC tumors with rich stroma in immunocompetent mice. In this #146 tumor model, the efficacy of FAKi was synergistically augmented when combined with G47Δ, which reflected not only a decreased stromal content but also a significant shifting of the tumor microenvironment toward immune stimulation. In transgenic autochthonous PKF mice, a rare model that develops stroma-rich PDAC with a 100% penetrance and resembles human PDAC in various aspects, the prolongation of survival compared with FAKi alone was achieved only when FAKi was combined with G47Δ and immune checkpoint inhibitors. The FAKi combination therapy may be useful to overcome the treatment resistance of stroma-rich PDAC.

Mirogabalin improves cancer-associated pain but increases the risk of malignancy in mice with pancreatic cancer.

ABSTRACT: Mirogabalin, a selective voltage-gated calcium channel α2δ ligand, improves peripheral neuropathic pain; however, its effects on patients with cancers including pancreatic ductal adenocarcinoma (PDAC) remain unknown. We analyzed the effects of mirogabalin on a KPPC ( LSL-KrasG12D/+; Trp53flox/flox; Pdx-1cre/+ ) mouse model of PDAC. Six-week-old KPPC mice received oral mirogabalin (10 mg/kg/day) (n = 10) or vehicle water (n = 14) until the humane end point. Cancer-associated pain was evaluated using the scores of hunching and mouse grimace scale (MGS). Tumor status and plasma cytokine levels were determined using histopathological analysis and cytokine array, respectively. The effects of mirogabalin on the proliferative ability of PDAC cell lines were determined. The scores of the hunching and MGS improved after mirogabalin administration with a decrease in the plasma levels of inflammatory cytokines, such as tumor necrosis factor-α, interleukin-6, and interferon-γ. Although no significant difference in the survival rate was observed, mirogabalin significantly increased pancreatic tumor size and proliferative index of Ki-67 and cyclins. Local arginase-1 + M2-like tumor-associated macrophages and CD31 + tumor blood vessels increased after mirogabalin administration. By contrast, the number of α-smooth muscle actin + cancer-associated fibroblasts, desmoplastic stroma, and CD8 + T cells decreased. Local myeloperoxidase + tumor-associated neutrophils and CD45R + B cells were unaltered. Mirogabalin enhanced the proliferative ability of PDAC cell lines with the upregulation of cyclins and cyclin-dependent kinases; however, it inhibited the potential of pancreatic stellate cells in vitro. Therefore, our results suggest that mirogabalin improves cancer-associated pain but enhances the proliferative potential of PDAC in vitro and in vivo.

HNF1B-driven three-dimensional chromatin structure for molecular classification in pancreatic cancers.

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.

Multiphasic Heterogeneity of Fibroblasts in the Microenvironment of Pancreatic Ductal Adenocarcinoma: Dissection and the Sum of the Dynamics.

Pancreatic cancer is still the most intractable cancer, with a 5-year survival of around 10%. To conquer the most common type, pancreatic ductal adenocarcinoma (PDAC), we need to understand its pathobiology, especially the tumor microenvironment (TME) that characteristically contains abundant stromal components, with marked fibrosis. In this Special Issue, "Tumor Microenvironment and Pancreatic Cancer", various aspects of TME were discussed, most frequently including articles related to cancer-associated fibroblasts (CAFs) and the extracellular matrix (ECM). CAFs and ECM have been considered in favor of PDAC cells; however, surprisingly, depleting CAFs or reducing the stromal components in PDAC-model mice induced aggressive PDAC and worsened the prognosis. Subsequently, accumulating studies have elucidated evidence of the heterogeneity of CAFs and the plasticity between the subtypes. Possible cancer-promoting and -restraining properties of the CAF subtypes have been suggested, but these are yet to be fully elucidated. Here, in addition to the extensive reviews on the heterogeneity of CAFs in this Special Issue, I refer to another insight from a recent integrative study of PDAC TME, that PDAC TME can be divided into three distinct sub-tumor microenvironments (subTMEs), and the co-existence of the distinct subTMEs is associated with poor prognosis. In the subTME, the heterogeneity of each component, including CAFs, can be changed transiently through various interactions in the TME, and the sum of the transient change and dynamic plasticity might be timely tuned in the co-existence of distinct subTMEs to contribute to the poor prognosis. Thus, understanding the more detailed underlying mechanisms in this heterogeneity of TME, as well as how to control the sum of multiphasic heterogeneity, might lead to the establishment of a more desirable therapeutic strategy to conquer intractable PDAC.

The Role of the Microbiome in Pancreatic Cancer.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies, with little improvement in outcomes in recent decades, although the molecular and phenotypic characterization of PDAC has contributed to advances in tailored therapies. PDAC is characterized by dense stroma surrounding tumor cells, which limits the efficacy of treatment due to the creation of a physical barrier and immunosuppressive environment. Emerging evidence regarding the microbiome in PDAC implies its potential role in the initiation and progression of PDAC. However, the underlying mechanisms of how the microbiome affects the local tumor microenvironment (TME) as well as the systemic immune system have not been elucidated in PDAC. In addition, therapeutic strategies based on the microbiome have not been established. In this review, we summarize the current evidence regarding the role of the microbiome in the development of PDAC and discuss a possible role for the microbiome in the early detection of PDAC in relation to premalignant pancreatic diseases, such as chronic pancreatitis and intraductal papillary mucinous neoplasm (IPMN). In addition, we discuss the potential role of the microbiome in the treatment of PDAC, especially in immunotherapy, although the biomarkers used to predict the efficacy of immunotherapy in PDAC are still unknown. A comprehensive understanding of tumor-associated immune responses, including those involving the microbiome, holds promise for new treatments in PDAC.

The Role of Neural Signaling in the Pancreatic Cancer Microenvironment.

Pancreatic cancer is one of the most lethal malignant diseases. Various cells in the tumor microenvironment interact with tumor cells and orchestrate to support tumor progression. Several kinds of nerves are found in the tumor microenvironment, and each plays an essential role in tumor biology. Recent studies have shown that sympathetic, parasympathetic, and sensory neurons are found in the pancreatic cancer microenvironment. Neural signaling not only targets neural cells, but tumor cells and immune cells via neural receptors expressed on these cells, through which tumor growth, inflammation, and anti-tumor immunity are affected. Thus, these broad-range effects of neural signaling in the pancreatic cancer microenvironment may represent novel therapeutic targets. The modulation of neural signaling may be a therapeutic strategy targeting the whole tumor microenvironment. In this review, we describe the current understanding of the role of nerves in the tumor microenvironment of various cancers, with an emphasis on pancreatic cancer. We also discuss the underlying mechanisms and the possibility of therapeutic applications.

Midazolam exhibits antitumour and anti-inflammatory effects in a mouse model of pancreatic ductal adenocarcinoma.

BACKGROUND: Anaesthesia and perioperative management contribute to long-term outcomes of patients with cancer, including pancreatic ductal adenocarcinoma. We assessed the antitumour, anti-inflammatory, and analgesic effects of midazolam on LSL-KrasG12D/+;Trp53flox/flox;Pdx-1cre/+ transgenic mice with pancreatic ductal adenocarcinoma. METHODS: Six-week-old transgenic mice were administered midazolam 30 mg kg-1 day-1 p.o. (n=13); midazolam 30 mg kg-1 day-1 with 1-(2-chlorophenyl)-N-methyl-N(1-methylpropyl)-3-isoquinoline carboxamide (PK11195) 3 mg kg-1 day-1 i.p., a peripheral benzodiazepine receptor antagonist (n=10); or vehicle (water; n=14) until the humane endpoint. Cancer-associated pain was evaluated using hunching score and mouse grimace scale. Tumour stage and immuno-inflammatory status were determined histopathologically. Anti-proliferative and apoptotic potentials of midazolam were investigated using mouse pancreatic ductal adenocarcinoma cell lines. RESULTS: Midazolam significantly inhibited tumour size and proliferative index of Ki-67 and cyclins in pancreatic ductal adenocarcinoma, which was blocked by administration of PK11195. Local myeloperoxidase+ tumour-associated neutrophils, arginase-1+ M2-like tumour-associated macrophages, and CD11b+Ly-6G+ polymorphonuclear myeloid-derived suppressor cells were reduced by midazolam, which was antagonised by administration of PK11195. Hunching and mouse grimace scale were improved by midazolam, whereas the scores increased with midazolam+PK11195 treatment. Plasma pro-inflammatory cytokines, such as interleukin-6 and CC chemokine ligand (CCL)2, CCL3, and CCL5, were reduced by midazolam, whereas these cytokines increased with PK11195. Midazolam inhibited pancreatic ductal adenocarcinoma proliferation through downregulation of cyclins and cyclin-dependent kinases and induced apoptosis in vitro. CONCLUSIONS: These results suggest that midazolam inhibits pancreatic ductal adenocarcinoma proliferation and local infiltration of tumour-associated neutrophils, tumour-associated macrophages, and polymorphonuclear myeloid-derived suppressor cells, thereby inhibiting pancreatic ductal adenocarcinoma progression.

MNX1-HNF1B Axis Is Indispensable for Intraductal Papillary Mucinous Neoplasm Lineages.

BACKGROUND & AIMS: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: Our organoid analyses identified the MNX1-HNF1B axis to be biologically significant in IPMN lineages.

Protein intake after the initiation of chemotherapy is an independent prognostic factor for overall survival in patients with unresectable pancreatic cancer: A prospective cohort study.

BACKGROUND & AIMS: This study was conducted to investigate the nutritional status and longitudinal dietary intake during the course of chemotherapy, and their relationships with the survival in patients with unresectable pancreatic cancer. METHODS: A prospective cohort study was conducted in 38 patients with unresectable pancreatic cancer receiving chemotherapy between January 2018 and November 2019. Subjective global assessment was used to assess the nutritional status, and the dietary intake was assessed monthly, for up to 12 months, using a brief self-administered diet history questionnaire. The primary outcome was overall survival, and the secondary outcome was progression-free survival. Cox regression analysis was performed to identify independent prognostic factors. RESULTS: Moderate or severe malnutrition was found in 34.2% of the participants. Daily protein intake was significantly higher in the survivor group than in the deceased group at one month after the initiation of chemotherapy (1.4 ± 0.7 g/kg/day vs. 0.9 ± 0.5 g/kg/day, p = 0.019), while the baseline nutritional intakes were similar between the two groups. Univariate analysis identified weight loss >3.5%, energy intake <25 kcal/kg/day, protein intake <1.1 g/kg/day, and malnutrition as possible poor prognostic factors. Multivariate analysis identified protein intake <1.1 g/kg/day (hazard ratio [HR]: 9.03, 95%CI: 1.45-56.32, p = 0.018) as an independent poor prognostic factor. CONCLUSIONS: Insufficient protein intake was identified as an independent poor prognostic factor in patients with unresectable pancreatic cancer receiving chemotherapy. Improving the dietary protein intake could be a useful therapeutic approach in patients with advanced pancreatic cancer receiving chemotherapy.

ABO Blood Group and Risk of Pancreatic Carcinogenesis in Intraductal Papillary Mucinous Neoplasms.

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.

Inhibition of histone methyltransferase G9a attenuates liver cancer initiation by sensitizing DNA-damaged hepatocytes to p53-induced apoptosis.

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.

Blocking VCAM-1 inhibits pancreatic tumour progression and cancer-associated thrombosis/thromboembolism.

OBJECTIVE: Pancreatic ductal adenocarcinoma (PDAC) is the deadliest cancer. Cancer-associated thrombosis/thromboembolism (CAT), frequently observed in PDAC, is known as a poor prognostic factor. Here, we investigated the underlying mechanisms between PDAC and CAT, and performed a trial of therapeutic approach for PDAC using a genetically engineered mouse model, PKF (Ptf1acre/+;LSL-KrasG12D/+;Tgfbr2flox/flox ). DESIGN: Presence of CAT in PKF mice was detected by systemic autopsy. Plasma cytokines were screened by cytokine antibody array. Murine and human plasma atrial natriuretic peptide (ANP) and soluble vascular cell adhesion molecule 1 (sVCAM-1) were determined by ELISA. Distribution of VCAM-1 in PKF mice and human autopsy samples was detected by immunohistochemistry. PKF mice were treated with anti-VCAM-1 antibody and the effects on survival, distribution of CAT and the tumour histology were analysed. RESULTS: We found spontaneous CAT with cardiomegaly in 68.4% PKF mice. Increase of plasma ANP and sVCAM-1 was observed in PKF mice and PDAC patients with CAT. VCAM-1 was detected in the activated endothelium and thrombi. Administration of anti-VCAM-1 antibody to PKF mice inhibited tumour growth, neutrophil/macrophage infiltration, tumour angiogenesis and progression of CAT; moreover, it dramatically extended survival (from 61 to 253 days, p<0.01). CONCLUSION: Blocking VCAM-1/sVCAM-1 might be a potent therapeutic approach for PDAC as well as CAT, which can contribute to the prognosis. Increase of plasma ANP and sVCAM-1 might be a diagnostic approach for CAT in PDAC.

A retrospective comparative study of S-IROX and modified FOLFIRINOX for patients with advanced pancreatic cancer refractory to gemcitabine plus nab-paclitaxel.

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.

Soluble VCAM-1 promotes gemcitabine resistance via macrophage infiltration and predicts therapeutic response in pancreatic cancer.

Pancreatic cancer is one of the malignant diseases with the worst prognosis. Resistance to chemotherapy is a major difficulty in treating the disease. We analyzed plasma samples from a genetically engineered mouse model of pancreatic cancer and found soluble vascular cell adhesion molecule-1 (sVCAM-1) increases in response to gemcitabine treatment. VCAM-1 was expressed and secreted by murine and human pancreatic cancer cells. Subcutaneous allograft tumors with overexpression or knock-down of VCAM-1, as well as VCAM-1-blocking treatment in the spontaneous mouse model of pancreatic cancer, revealed that sVCAM-1 promotes tumor growth and resistance to gemcitabine treatment in vivo but not in vitro. By analyzing allograft tumors and co-culture experiments, we found macrophages were attracted by sVCAM-1 to the tumor microenvironment and facilitated resistance to gemcitabine in tumor cells. In a clinical setting, we found that the change of sVCAM-1 in the plasma of patients with advanced pancreatic cancer was an independent prognostic factor for gemcitabine treatment. Collectively, gemcitabine treatment increases the release of sVCAM-1 from pancreatic cancer cells, which attracts macrophages into the tumor, thereby promoting the resistance to gemcitabine treatment. sVCAM-1 may be a potent clinical biomarker and a potential target for the therapy in pancreatic cancer.

Inhibition of transforming growth factor-ß signaling in myeloid cells ameliorates aortic aneurysmal formation in Marfan syndrome.

Increased transforming growth factor-ß (TGF-ß) signaling contributes to the pathophysiology of aortic aneurysm in Marfan syndrome (MFS). Recent reports indicate that a small but significant number of inflammatory cells are infiltrated into the aortic media and adventitia in MFS. However, little is known about the contribution of myeloid cells to aortic aneurysmal formation. In this study, we ablated the TGF-ß type II receptor gene Tgfbr2 in myeloid cells of Fbn1C1039G/+ MFS mice (Fbn1C1039G/+;LysM-Cre/+;Tgfbr2fl/fl mice, hereinafter called Fbn1C1039G/+;Tgfbr2MyeKO) and evaluated macrophage infiltration and TGF-ß signaling in the aorta. Aneurysmal formation with fragmentation and disarray of medial elastic fibers observed in MFS mice was significantly ameliorated in Fbn1C1039G/+;Tgfbr2MyeKO mice. In the aorta of Fbn1C1039G/+;Tgfbr2MyeKO mice, both canonical and noncanonical TGF-ß signals were attenuated and the number of infiltrated F4/80-positive macrophages was significantly reduced. In vitro, TGF-ß enhanced the migration capacity of RAW264.7 macrophages. These findings suggest that TGF-ß signaling in myeloid cells promotes aortic aneurysmal formation and its inhibition might be a novel therapeutic target in MFS.