Should Ki67 immunohistochemistry be performed on all lesions in multifocal small intestinal neuroendocrine tumours?

AIMS

Well-differentiated small intestinal neuroendocrine tumours (SI-NETs) are often multifocal, and this has been suggested to impart worse disease-free survival. Practice guidelines have not been established for World Health Organisation (WHO) grading of multiple primary lesions.

METHODS AND RESULTS

We identified 68 patients with ileal/jejunal SI-NET for a combined total of 207 primary lesions. Each case was evaluated for patient age and sex; size of all tumours; presence of lymph node metastases, mesenteric tumour deposits or distant metastases; and disease-specific outcome. Ki67 staining was performed on all 207 primary lesions. The relationship between multifocality and clinicopathological factors was compared using Fisher's exact test. Outcome was tested using Cox proportional hazard regression. Forty-two patients had unifocal disease, and 26 had multifocal disease (median five lesions, range = 2-32). Most tumours were WHO grade 1 (201 of 207, 97%). Of the five patients with grades 2/3 tumours, three patients had unifocal disease, one patient had two subcentimetre grade 2 lesions (including the largest) and eight subcentimetre grade 1 lesions, and one patient had one 1.6-cm grade 3 lesion and one subcentimetre grade 1 lesion. There was a positive correlation between tumour size and Ki67 index (coefficient 0.28; 95% confidence interval 0.05-0.52, P = 0.017). There was no significant association between multifocality and nodal metastases, mesenteric tumour deposits, distant metastases or disease-specific survival.

CONCLUSIONS

In patients with multifocal SI-NET, unless a particular lesion has a high mitotic rate, only staining the largest lesion for Ki67 should serve to grade almost all cases accurately. Multifocality does not appear to significantly impact patient survival.

Tobacco Carcinogen-Induced Production of GM-CSF Activates CREB to Promote Pancreatic Cancer

Although smoking is a significant risk factor for pancreatic ductal adenocarcinoma (PDAC), the molecular mechanisms underlying PDAC development and progression in smokers are still unclear. Here, we show the role of cyclic AMP response element-binding protein (CREB) in the pathogenesis of smoking-induced PDAC. Smokers had significantly higher levels of activated CREB when compared with nonsmokers. Cell lines derived from normal pancreas and pancreatic intraepithelial neoplasm (PanIN) exhibited low baseline pCREB levels compared with PDAC cell lines. Furthermore, elevated CREB expression correlated with reduced survival in patients with PDAC. Depletion of CREB significantly reduced tumor burden after tobacco-specific nitrosamine 4-(methyl nitrosamino)-1-(3-pyridyl)-1-butanone (NNK) treatment, suggesting a CREB-dependent contribution to PDAC growth and progression in smokers. Conversely, NNK accelerated PanIN lesion and PDAC formation via GM-CSF-mediated activation of CREB in a PDAC mouse model. CREB inhibition (CREBi) in mice more effectively reduced primary tumor burden compared with control or GM-CSF blockade alone following NNK exposure. GM-CSF played a role in the recruitment of tumor-associated macrophages (TAM) and regulatory T cell (Treg) expansion and promotion, whereas CREBi significantly reduced TAM and Treg populations in NNK-exposed mice. Overall, these results suggest that NNK exposure leads to activation of CREB through GM-CSF, promoting inflammatory and Akt pathways. Direct inhibition of CREB, but not GM-CSF, effectively abrogates these effects and inhibits tumor progression, offering a viable therapeutic strategy for patients with PDAC.Significance: These findings identify GM-CSF-induced CREB as a driver of pancreatic cancer in smokers and demonstrate the therapeutic potential of targeting CREB to reduce PDAC tumor growth.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/21/6146/F1.large.jpg Cancer Res; 78(21); 6146-58. ©2018 AACR.

Somatostatin receptor 2 signaling promotes growth and tumor survival in small-cell lung cancer

Somatostatin receptor 2 (SSTR2) is overexpressed in a majority of neuroendocrine neoplasms, including small-cell lung carcinomas (SCLCs). SSTR2 was previously considered an inhibitory receptor on cell growth, but its agonists had poor clinical responses in multiple clinical trials. The role of this receptor as a potential therapeutic target in lung cancer merits further investigation. We evaluated the expression of SSTR2 in a cohort of 96 primary tumors from patients with SCLC and found 48% expressed SSTR2. Correlation analysis in both CCLE and an SCLC RNAseq cohort confirmed high-level expression and identified an association between NEUROD1 and SSTR2. There was a significant association with SSTR2 expression profile and poor clinical outcome. We tested whether SSTR2 expression might contribute to tumor progression through activation of downstream signaling pathways, using in vitro and in vivo systems and downregulated SSTR2 expression in lung cancer cells by shRNA. SSTR2 downregulation led to increased apoptosis and dramatically decreased tumor growth in vitro and in vivo in multiple cell lines with decreased AMPKα phosphorylation and increased oxidative metabolism. These results demonstrate a role for SSTR2 signaling in SCLC and suggest that SSTR2 is a poor prognostic biomarker in SCLC and potential future therapeutic signaling target.

Inverse Correlation of STAT3 and MEK Signaling Mediates Resistance to RAS Pathway Inhibition in Pancreatic Cancer

Major contributors to therapeutic resistance in pancreatic ductal adenocarcinoma (PDAC) include Kras mutations, a dense desmoplastic stroma that prevents drug delivery to the tumor, and activation of redundant signaling pathways. We have previously identified a mechanistic rationale for targeting STAT3 signaling to overcome therapeutic resistance in PDAC. In this study, we investigate the molecular mechanisms underlying the heterogeneous response to STAT3 and RAS pathway inhibition in PDAC. Effects of JAK/STAT3 inhibition (STAT3i) or MEK inhibition (MEKi) were established in Ptf1a^cre/+; LSL-Kras^G12D/+ ; and Tgfbr2^flox/flox (PKT) mice and patient-derived xenografts (PDX). Amphiregulin (AREG) levels were determined in serum from human patients with PDAC, LSL-Kras^G12D/+;Trp53^R172H/+;Pdx1^Cre/+ (KPC), and PKT mice. MEKi/STAT3i-treated tumors were analyzed for integrity of the pancreas and the presence of cancer stem cells (CSC). We observed an inverse correlation between ERK and STAT3 phosphorylation. MEKi resulted in an immediate activation of STAT3, whereas STAT3i resulted in TACE-induced, AREG-dependent activation of EGFR and ERK. Combined MEKi/STAT3i sustained blockade of ERK, EGFR, and STAT3 signaling, overcoming resistance to individual MEKi or STAT3i. This combined inhibition attenuated tumor growth in PDX and increased survival of PKT mice while reducing serum AREG levels. Furthermore, MEKi/STAT3i altered the PDAC tumor microenvironment by depleting tumor fibrosis, maintaining pancreatic integrity, and downregulating CD44⁺ and CD133⁺ CSCs. These results demonstrate that resistance to MEKi is mediated through activation of STAT3, whereas TACE-AREG-EGFR-dependent activation of RAS pathway signaling confers resistance to STAT3 inhibition. Combined MEKi/STAT3i overcomes these resistances and provides a novel therapeutic strategy to target the RAS and STAT3 pathway in PDAC.Significance: This report describes an inverse correlation between MEK and STAT3 signaling as key mechanisms of resistance in PDAC and shows that combined inhibition of MEK and STAT3 overcomes this resistance and provides an improved therapeutic strategy to target the RAS pathway in PDAC.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/21/6235/F1.large.jpg Cancer Res; 78(21); 6235-46. ©2018 AACR.

Mesenteric tumour deposits arising from small-intestine neuroendocrine tumours are frequently associated with fibrosis and IgG4-expressing plasma cells

AIMS

Mesenteric tumour deposits frequently occur in small-intestine neuroendocrine tumours. In many instances, these mesenteric tumour deposits are surrounded by a dense fibrotic stroma and have associated lymphoplasmacytic inflammation. The aim of this study was to examine whether mesenteric tumour deposits in patients with small-intestine NETs neuroendocrine tumours show histological and immunophenotypic overlap with IgG4-related sclerosing mesenteritis.

METHODS AND RESULTS

Sixty-six mesenteric tumour deposits from 66 patients with small-intestine neuroendocrine tumours with blocks available for further studies were identified from our archives. Cases were assessed for clinicopathological features and the presence of IgG4-positive and IgG-positive plasma cells by immunohistochemistry. Ratios of IgG4-positive to IgG-positive plasma cells were calculated. Seventeen mesenteric tumour deposits (26%) showed >40 IgG4-positive plasma cells per high-power field, and the majority of cases (68%) showed at least some staining of IgG4-positive plasma cells. Mesenteric tumour deposits with >20 IgG4-positive plasma cells per high-power field tended to be larger (25.9 ± 13.0 mm versus 18.6 ± 15.8 mm; P = 0.07), and had more IgG-positive plasma cells (88 ± 24 versus 36 ± 37; P < 0.01) and a higher IgG4-positive/IgG-positive plasma cell ratio (0.66 ± 0.18 versus 0.17 ± 0.25; P < 0.01). All but one mesenteric tumour deposit with >20 IgG4-positve plasma cells had a ratio of >40%.

CONCLUSIONS

IgG4 expression is frequent in mesenteric tumour deposits from small-intestine neuroendocrine tumours. Undersampling of tumour on biopsies of mesenteric tumour deposits could potentially cause diagnostic confusion with IgG4-related sclerosing mesenteritis.

Ornithine Decarboxylase in Macrophages Exacerbates Colitis and Promotes Colitis-Associated Colon Carcinogenesis by Impairing M1 Immune Responses

Ornithine decarboxylase (ODC) is the rate-limiting enzyme for polyamine biosynthesis and restricts M1 macrophage activation in gastrointestinal (GI) infections. However, the role of macrophage ODC in colonic epithelial-driven inflammation is unknown. Here, we investigate cell-specific effects of ODC in colitis and colitis-associated carcinogenesis (CAC). Human colonic macrophages expressed increased ODC levels in active ulcerative colitis and Crohn's disease, colitis-associated dysplasia, and CAC. Mice lacking Odc in myeloid cells (OdcΔmye mice) that were treated with dextran sulfate sodium (DSS) exhibited improved survival, body weight, and colon length and reduced histologic injury versus control mice. In contrast, GI epithelial-specific Odc knockout had no effect on clinical parameters. Despite reduced histologic damage, colitis tissues of OdcΔmye mice had increased levels of multiple proinflammatory cytokines and chemokines and enhanced expression of M1, but not M2 markers. In the azoxymethane-DSS model of CAC, OdcΔmye mice had reduced tumor number, burden, and high-grade dysplasia. Tumors from OdcΔmye mice had increased M1, but not M2 macrophages. Increased levels of histone 3, lysine 9 acetylation, a marker of open chromatin, were manifest in tumor macrophages of OdcΔmye mice, consistent with our findings that macrophage ODC affects histone modifications that upregulate M1 gene transcription during GI infections. These findings support the concept that macrophage ODC augments epithelial injury-associated colitis and CAC by impairing the M1 responses that stimulate epithelial repair, antimicrobial defense, and antitumoral immunity. They also suggest that macrophage ODC is an important target for colon cancer chemoprevention.Significance: Ornithine decarboxylase contributes to the pathogenesis of colitis and associated carcinogenesis by impairing M1 macrophage responses needed for antitumoral immunity; targeting ODC in macrophages may represent a new strategy for chemoprevention. Cancer Res; 78(15); 4303-15. ©2018 AACR.

A precision oncology approach to the pharmacological targeting of mechanistic dependencies in neuroendocrine tumors

We introduce and validate a new precision oncology framework for the systematic prioritization of drugs targeting mechanistic tumor dependencies in individual patients. Compounds are prioritized on the basis of their ability to invert the concerted activity of master regulator proteins that mechanistically regulate tumor cell state, as assessed from systematic drug perturbation assays. We validated the approach on a cohort of 212 gastroenteropancreatic neuroendocrine tumors (GEP-NETs), a rare malignancy originating in the pancreas and gastrointestinal tract. The analysis identified several master regulator proteins, including key regulators of neuroendocrine lineage progenitor state and immunoevasion, whose role as critical tumor dependencies was experimentally confirmed. Transcriptome analysis of GEP-NET-derived cells, perturbed with a library of 107 compounds, identified the HDAC class I inhibitor entinostat as a potent inhibitor of master regulator activity for 42% of metastatic GEP-NET patients, abrogating tumor growth in vivo. This approach may thus complement current efforts in precision oncology.

Abstract 5042: CREB transgenic mice to study alcohol-associated pancreatic carcinogenesis

Background: Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer-related deaths in the United States. Chronic alcohol (&gt;60 grams/day) consumption is strongly associated with the risk of PDAC development. The metabolites generated from alcohol have been shown to cause significant pancreatic injury. Although the association of alcohol with PDAC progression has been established, the details of the underlying molecular and cellular mechanisms governing this process are unknown. Our study revealed that alcohol-associated pancreatic carcinogenesis correlates with CXCL12-induced activation of cyclic AMP response element binding protein (CREB). In this study, we examined newly developed CREB knockout (CREBfl/fl) mouse in pancreas.

Methods: Human pancreatic epithelial lines (HPNE), HPNE cells with KRAS (HPNE-KRAS), pancreatic stellate cells (PSCs), pancreatic intraepithelial neoplasia (PanIN) mouse cell lines (LSL-KrasG12D/+; Pdx1Cre/+) and cancer-associated fibroblasts (CAFs) cells were exposed to chronic alcohol (50 mM) and analyzed for phospho-kinases in cell lysates and cytokines in conditioned media. Inducible Ptf1aCreERTM;KRASG12D/+ (iPK) mice and CREB knockout (CREBfl/fl) with KRAS activation [Ptf1aCreERTM;KRASG12D/+;CREBfl/fl (iPKCREBKO)] mice were used to investigate the effect of alcohol on CREB activation and the role of CREB in alcohol-associated PDAC pathogenesis. iPK and iPKCREBKO mice were exposed to Lieber-DeCarli alcohol diet for up to 14 weeks with or without caerulein injections. The number of acinar cells (amylase), ducts (cytokeratin 19), PanIN lesions (alcian blue positive), fibrosis (sirius red) and activation of CREB were measured by immunohistochemistry at 6 and 14 weeks of alcohol exposure in vivo. Serum obtained from alcohol-fed iPK and iPKCREBKO mice were analyzed for significant cytokine release upon alcohol exposure in vivo. We then determined the biologic effects of pharmacologic CREB inhibition in iPK mice exposed to alcohol diet.

Results: We found increased pCREB levels in HPNE and HPNE-KRAS cells upon treatment with alcohol, which was further associated with the up-regulation of the CXCL12 protein in the conditioned media. Serum CXCL12 and tissue pCREB levels were high in alcohol fed iPK mice when compared to their corresponding control diet-fed mice. Blocking CXCL12 with Plerixafor, a CXCL12-CXCR4 axis inhibitor, decreased alcohol-induced pCREB levels. Finally, exposure of iPK mice to an alcohol diet coupled with cerulein administration significantly increased the number of PanIN lesions (alcian blue+ cells), and decreased acinar cells when compared to alcohol-fed iPKCREBKO mice.

Conclusion: These findings implicate CREB as a critical oncogenic driver in alcohol addiction-induced pancreatic carcinogenesis. Additionally, CXCL12 represents an important mediator of CREB activation, which can be pharmacologically targeted.

Citation Format: Tulasigeri Totiger, Supriya Srinivasan, Michael VanSaun, Chandrashekhar Joshi, Chanjuan Shi, Xizi Dai, Rajinder Dawra, Alexander Gaidarski, Eric Nestler, Nipun Merchant, Nagaraj Nagathihalli. CREB transgenic mice to study alcohol-associated pancreatic carcinogenesis [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 5042.

Abstract 1249: Animal model in the prevention of alcoholic pancreatitis

Background: Alcohol abuse is a major risk factor for pancreatitis. Alcohol addiction-induced molecular pathogenesis of pancreatitis remains obscure, and no current effective treatment exists. Therefore, approaches to investigate pathogenesis, prevention and cellular mechanisms by which alcohol causes pancreatitis are necessary for establishing therapeutics. Our efforts demonstrate that alcohol induces activation of a major intracellular transcriptional factor, cyclic AMP response element-binding protein (CREB). We further investigated the functional role of CREB in alcohol-induced pathogenesis of pancreatitis using cellular and genetic mouse models of pancreas.

Materials and Methods: Human tissue microarrays were immunostained to determine the significance of pCREB expression among pancreatic tissues obtained from normal and chronic pancreatitis. Rat acinar cell line AR42J and mouse PSCs (mPSCs) were exposed to alcohol (50 mMol/L). Inducible Ptf1aCreERTM knockin mice and Ptf1aCreERTM;CREBfl/fl (iPC) mice were fed with Lieber Decarli diet alcohol or regular diet for 14 weeks with or without caerulein (50 µg/kg). Mice were then euthanized 24 hours after the last caerulein injection, and pancreas tissues were processed for morphometric analysis (necrosis, vacuolization, hemorrhage, edema and inflammation) and immunohistochemical analysis of amylase, trichrome blue, SMA, collagen 1, fibronectin and pCREB expression. To determine whether alcohol accelerated morbidity in mice, we evaluated pathogenesis of chronic pancreatitis by analyzing acinar atrophy and pancreatic fibrosis.

Results: Expression of pCREB was significantly higher (p &lt;0.001) in chronic pancreatitis vs. normal patient tissues, confirming the role of activated CREB in pancreatitis. Activated CREB levels were very high in alcohol-fed Ptf1aCreERTM mice when compared with control diet-fed mice. Pancreatic sections from alcohol-fed mice challenged with caerulein revealed significantly higher score of acinar cell vacuolization and necrosis, inflammatory infiltrate and hemorrhage compared with minimal lesions in control diet-fed animals receiving caerulein. Pancreatic sections from alcohol-fed Ptf1aCreERTM animals showed higher score of histologic injury, extracellular matrix deposition, collagen deposition and increased pancreatic fibrosis when compared with control-fed mice. iPC mice showed decrease in the pathogenesis of chronic pancreatitis when compared to Ptf1aCreERTM mice with alcohol.

Conclusion: CREB is overexpressed in pancreatitis and alcohol activates CREB, which then drives pathogenesis of pancreatitis. Severity of pancreatitis in response to alcohol is diminished in the absence of CREB. Therefore, we conclude that targeting CREB represents a promising treatment for alcohol-induced pancreatitis.

Citation Format: Supriya Srinivasan, Tulasigeri Totiger, Michael VanSaun, Fanuel Messaggio, Chanjuan Shi, Austin Dosch, Eric Nestler, Nipun Merchant, Nagaraj Nagathihalli. Animal model in the prevention of alcoholic pancreatitis [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 1249.

Depression and survival of glioma patients: A systematic review and meta-analysis

INTRODUCTION

There is currently a lack of a well-formed consensus regarding the effects of depression on the survival of glioma patients. A more thorough understanding of such effects may better highlight the importance of recognizing depressive symptoms in this patient population and guide treatment plans in the future.

OBJECTIVE

The aim of this meta-analysis was to study the effect of depression on glioma patients' survival.

METHODS

A meta-analysis was conducted according to the PRISMA guidelines. PubMed, Embase, and Cochrane databases were searched for studies that reported depression and survival among glioma patients through 11/06/2016. Both random-effects (RE) and fixed-effect (FE) models were used to compare survival outcomes in glioma patients with and without depression.

RESULTS

Out of 619 identified articles, six were selected for the meta-analysis. Using RE model, the various measures for survival outcomes displayed worsened outcomes for both high and low-grade glioma patients with depression compared to those without depression. For binary survival outcomes, the overall pooled risk ratio for survival was 0.70 (95% CI: 0.47, 1.04; 6 studies; I² = 54.9%, P-heterogeneity = 0.05) for high grade gliomas (HGG) and 0.28 (95% CI: 0.04, 1.78; I² = 0%, P-heterogeneity = 1.00; one study) for low grade gliomas (LGG) was. A sub-group analysis in the HGG group by depression timing (pre- versus post-operative) revealed no differences between depression and survival outcomes (P-interaction = 0.47). For continuous survival outcomes, no statistically significant difference was found among the high and low-grade glioma groups (P-interaction = 0.31). The standardized mean difference (SMD) in survival outcomes was -0.56 months (95%CI: -1.13, 0.02; 4 studies, I² = 89.4%, P-heterogeneity < 0.01) for HGG and -1.69 months (95%CI: -3.26, -0.13; one study; I² = 0%, P-heterogeneity = 1.00) for LGG. In patients with HGG, the pooled HR of death also showed a borderline significant increased risk of death among depressive patients (HR 1.42, 95% CI: 1.00, 2.01). Results using the FE model were not materially different.

CONCLUSIONS

Depression was associated with significantly worsened survival regardless of time of diagnosis, especially among patients with high-grade glioma.

Epithelial Smad4 Deletion Up-Regulates Inflammation and Promotes Inflammation-Associated Cancer

Background & Aims

Chronic inflammation is a predisposing condition for colorectal cancer. Many studies to date have focused on proinflammatory signaling pathways in the colon. Understanding the mechanisms that suppress inflammation, particularly in epithelial cells, is critical for developing therapeutic interventions. Here, we explored the roles of transforming growth factor β (TGFβ) family signaling through SMAD4 in colonic epithelial cells.

Methods

The Smad4 gene was deleted specifically in adult murine intestinal epithelium. Colitis was induced by 3 rounds of dextran sodium sulfate in drinking water, after which mice were observed for up to 3 months. Nontransformed mouse colonocyte cell lines and colonoid cultures and human colorectal cancer cell lines were analyzed for responses to TGFβ1 and bone morphogenetic protein 2.

Results

Dextran sodium sulfate treatment was sufficient to drive carcinogenesis in mice lacking colonic Smad4 expression, with resulting tumors bearing striking resemblance to human colitis-associated carcinoma. Loss of SMAD4 protein was observed in 48% of human colitis-associated carcinoma samples as compared with 19% of sporadic colorectal carcinomas. Loss of Smad4 increased the expression of inflammatory mediators within nontransformed mouse colon epithelial cells in vivo. In vitro analysis of mouse and human colonic epithelial cell lines and organoids indicated that much of this regulation was cell autonomous. Furthermore, TGFβ signaling inhibited the epithelial inflammatory response to proinflammatory cytokines.

Conclusions

TGFβ suppresses the expression of proinflammatory genes in the colon epithelium, and loss of its downstream mediator, SMAD4, is sufficient to initiate inflammation-driven colon cancer. Transcript profiling: GSE100082.

Hepatic micrometastases are associated with poor prognosis in patients with liver metastases from neuroendocrine tumors of the digestive tract

Pathologic examination of hepatic metastasectomies from patients with metastatic small intestinal or pancreatic neuroendocrine tumor frequently reveals micrometastases undetectable by radiologic or macroscopic gross examination. This finding raises the possibility that undetectable micrometastases remain in these patients after metastasectomy. Here we examined liver resections for micrometastases and assessed their impact on prognosis. Hepatic metastasectomies from 65 patients with neuroendocrine tumor of the small intestine (N = 43) or pancreas (N = 22) were reviewed for the presence of micrometastases, which were defined as microscopic tumor foci ≤1 mm in greatest dimension. Medical records were also reviewed for patient demographics, clinical history, and follow-up data. Micrometastasis was identified in 36 (55%) of 65 hepatic resection specimens. More hepatic micrometastases were seen in small intestinal cases than in pancreatic cases (29/43, 67%, versus 7/22, 32%; P < .01). They were typically present within portal tracts, sometimes with extension into the periportal region or sinusoidal spaces away from the portal tracts. Patients without hepatic micrometastases had fewer macrometastases or more R0 hepatic resections than those with micrometastases. The presence of hepatic micrometastases was associated with poor overall survival both before (hazard ratio [HR] 3.43; 95% CI 1.14-10.30; P = .03) and after accounting for confounding variables in stratified Cox regression (HR 4.82; 95% CI 1.0621.79; P = .04). In conclusion, hepatic micrometastases are common in patients with metastatic small intestinal or pancreatic neuroendocrine tumor and are independently associated with poor prognosis. These data suggest that surgical resection of hepatic metastases is likely not curative in these patients.

[Research Progress and Forensic Application on the Pathogenesis of Coronary Artery Spasm]

Coronary artery spasm （CAS） is a hyper-contraction of segmental coronary artery in response to multiple stimuli. At present, it's still in lack of specific diagnostic indicators of sudden cardiac death caused by CAS. This review summarizes current researches on the mechanisms of CAS and describes the roles of vascular endothelial dysfunction and vascular smooth muscle hypersensitivity in the course of CAS. Furthermore, the molecular mechanisms of the endogenous NO and endothelin-1 cause vascular endothelial dysfunction, and the phosphorylation of MLC2, Rho kinase and endoplasmic reticulum stress related to vascular smooth muscle hypersensitivity are discussed. Meanwhile, the possibility of forensic application for the related molecules on the diagnosis of sudden cardiac death caused by CAS are also explored.

Effects of supplementing sow diets with fermented corn and soybean meal mixed feed during lactation on the performance of sows and progeny

In the present study, two experiments were performed to study the effects of feeding fermented corn and soybean meal mixed feed (FMF) with Bacillus subtilis and Enterococcus faecium to lactating sows on the performance of the sows and their progeny. In experiment 1, 60 sows were allocated to the following three dietary treatments: 1) sows fed a corn and soybean meal basal diet (control) from day 3 before parturition to weaning, 2) sows fed a diet with 7.5% FMF, and 3) sows fed a diet with 15% FMF. Results indicated that feeding 15% FMF significantly improved (P < 0.05) the sows' ADFI, the individual piglet weaning weights, and piglet weight gain and reduced (P < 0.05) the backfat loss of sows compared with the control group. However, the 7.5% FMF treatment did not alter the performance of the sows or their progeny. Therefore, we considered the level of 15% FMF to be more efficient than 7.5% FMF. To verify the results of experiment 1, we performed experiment 2, in which 60 sows at 111 d of gestation were allocated into the following two dietary treatments: 1) sows fed a basal lactation diet (control) from d 111 of gestation to weaning and 2) sows fed a basal diet with 15% FMF. Compared with the control group, 15% FMF inclusion significantly increased (P < 0.05) the sows' ADFI, litter weight gain, and individual piglet weight gain during lactation and markedly decreased the backfat loss of sows (P < 0.05) and piglet diarrhea incidence (P < 0.05). Additionally, the milk yield and IgA contents of the milk in sows fed 15% FMF were greater (P < 0.05) than those of the control group. Furthermore, the apparent total tract digestibility of GE, DM, and total P of sows was increased (P < 0.05) with 15% FMF supplementation. Therefore, the present study indicates that supplementing sow diets with 15% FMF from parturition to weaning has the potential to 1) increase sow ADFI, milk production, milk IgA content, and nutrient digestibility and promote sow reproductive performance by shortening the weaning-to-estrous interval and 2) promote the growth performance of their progeny and decrease diarrhea incidence.

Frequent BRAF mutations suggest a novel oncogenic driver in colonic neuroendocrine carcinoma

BACKGROUND AND OBJECTIVES

The World Health Organization (WHO) 2010 has classified GI neuroendocrine neoplasms into neuroendocrine tumor (NET) and high-grade neuroendocrine carcinoma (NEC). The genetic underpinnings of NEC are poorly understood. The aim of the study was to perform genomic profiling of NEC to better characterize this aggressive disease.

METHODS

We identified nine patients with colonic NEC between January 1, 2005 and June 30, 2013. Whole exome sequencing (WES) was performed on tumor DNA from two patients with ≥80% tumor cellularity and matched normal tissue available. Focused BRAF mutational analysis was performed on an additional seven patients via sanger sequencing of BRAF exons 11 and 15.

RESULTS

We identified BRAF exon 15 mutations (c.A1781G: p.D594G and c.T1799A: p.V600E) by WES in two patients. Upon additional screening of seven colonic NECs for BRAF exon 11 and 15 mutations, we identified BRAF V600E mutations in two of seven specimens (29%). Overall, BRAF exon 15 mutations were present in four of nine colonic NECs.

CONCLUSION

Colonic NEC is a rare but aggressive tumor with high frequency (44%) of BRAF mutations. Further investigation is warranted to ascertain the incidence of BRAF mutations in a larger population as BRAF inhibition may be a potential avenue of targeted treatment for these patients.

Adenocarcinoma Ex goblet cell: A retrospective experience

847

Background: Adenocarcinoma ex goblet cell tumors (AGCC) represent rare appendiceal neoplasms with neuroendocrine and adenocarcinoma features. They represent the most aggressive subset of goblet cell carcinoids (Group B and C) and are often categorized as chemotherapy unresponsive [Am J SurgPathol.2008;32(10):1429-43]. Despite this, most patients with AGCC are treated with colon cancer chemotherapy regimens. We explored outcomes in patients treated at our institution with these regimens. Methods: We performed a single center retrospective analysis of 22 biopsy-proven AGCC patients (13 men, 9 women, median age at diagnosis 54.5) at Vanderbilt who had undergone treatment for local or metastatic disease. PFS and OS were determined for each patient and stratified by features listed on Table 1. Patients who were lost to follow up were censored based on their last recorded clinic date. Results: 16 patients received chemotherapy in the metastatic setting and all 16 had peritoneal involvement; of these patients 4 underwent HIPEC. Median PFS and OS in HIPEC treated patients was 17 months and 33 months respectively. 8 patients received adjuvant chemotherapy with FOLFOX; 6 in the local setting and 2 in the metastatic setting. Patients with metastatic AGCC had a median PFS of 21.5 months and a median OS of 32.9 months. Patients with local disease had a median PFS of 32.8 months and an OS that was not reached (median duration of follow up 12.4 months). Conclusions: AGCC have a predilection for peritoneal spread. Patients who received either adjuvant FOLFOX post definitive surgery or FOLFOX/FOLFIRI in the metastatic setting post optimal cytoreduction had prolonged periods of PFS and OS. [Table: see text]

[Genetic characterization of norovirus isolated in an outbreak of gastroenteritis in Jiangsu province]

Objective: To analyze the genetic characterization of norovirus isolated in an outbreak of gastroenteritis in Jiangsu province. Methods: Extracted viral RNA from the swab samples of cases of acute gastroenteritis outbreak in Jiangsu province on December 16-27, 2016 was reversely transcribed to cDNA, and partial RNA-dependent RNA polymerase sequence and complete capsid sequence (VP1) were amplified by RT-PCR. Amplification products were sequenced for the analysis of genetic characteristics. Results: Based on sequence alignment, the variant shared a high level of identity with the strain GⅡ.g isolated in Spain and Finland (98.7%) in the RNA-dependent RNA polymerase region, and with the strain GⅡ.1 isolated in American (99.4%) in the VP1. The recombination was determined by using software Simplot, and the breakpoint of recombination was located in the ORF1/2 overlap region at position 5 106 of VP1. The result of amino acids alignment in capsid region showed that there were no mutations in the amino acids of the predicted epitopes and receptor binding site Ⅰ-Ⅲ, but a unique amino acid change was detected at position 132 (N-S). Conclusion: The norovirus isolated in the outbreak of gastroenteritis in Jiangsu province was a rare recombinant norovirus variant GⅡ.g-GⅡ.1.

[The relationship between the recurrence of benign paroxysmal positional vertigo and the level of bone mineral as well as estrogen in postmenopausal women]

Objective: To investigate the relationship between the recurrence of benign paroxysmal positional vertigo(BPPV) and the levels of bone mineral density(BMD) and estrogen in postmenopausal women. Methods: A total of 38 postmenopausal women with recurrent BPPV were recruited as study group, in the First Affiliated Hospital of Soochow University from December 2013 to June 2017. Meanwhile, 49 normal menopausal women were included as control. All patients were natural menopausal for over one year.The patients were diagnosed as BPPV based on results of Dix-Hallpike test and Roll-test, with at least two episodes of recurrent onset. In the subjects, BMD was measured by dual X-ray absorptiometry of lumbar vertebrae. Estrogen levels were obtained by testing serum estradiol (E2) levels in early morning fasting venous blood. In the present study, we compared the level of E2 and the value of BMD in two groups by SPSS 21.0. In the study group, patients with decreased BMD were divided into two groups: treatment and untreated group. The recurrence rate of BPPV was compared between the two groups within 12 months. Results: ①The averagel levels of E2 and BMD in the study group were (16.21±11.00)ng/L and -1.68±0.98) respectively, which were significantly lower than those in the control group (t value was 7.03 and 8.05 respectively, both P<0.05). The averagel levels of E2 and BMD incontrol group were(28.52±6.34)ng/L and -0.18±0.77 respectively. ②The number of patients with decreased BMD in the study group (30 cases) was more than that in control group (6 cases), and the difference was statistically significant (P<0.05). ③ The recurrence rate of BPPV in treatment group [17.6%(3/17)] was significantly lower than that of untreated group [61.5%(8/13)], and the difference was statistically significant (P<0.05). Conclusion: Recurrent BPPV in postmenopausal women usually accompany with low levels of estrogen and BMD. Active treatment is helpful for their recurrence of BPPV.

Abstract A17: Molecular and clinicopathological features of native Nigerian colorectal cancer

Colorectal cancer (CRC) needs no introduction in Africa; once a rare cancer type, it is now the 3rd or 4th most common cancer. However, there are significant differences in the incidence rates, tumor biology, and clinical behavior in comparison to other populations. While the total incidence rates are about one-tenth of those in the developed world, Nigerian CRC occurs at a younger age and rapidly metastasizes. Molecular pathology and genetics of African CRC have not been comprehensively studied. In addition to better understanding of the biology of African CRC, analysis of genetic and molecular biomarkers, including microsatellite instability (MSI), is aimed at improving CRC diagnosis, treatment, and prognosis in Africa. We obtained 83 CRC paraffin-embedded blocks from the University of Ibadan and private pathology laboratories in Ibadan collected in the period from 2007 to 2014. Median age of the cases was 56±14.6 years with equal number of males and females. More than 60% of the patients had stage III and IV CRC. The majority were adenocarcinomas (76%) with a relatively high prevalence of mucinous adenocarcinoma (10%) and signet ring carcinoma (4%). Of all patients, 66% had rectal cancer. Poorly differentiated tumors were observed in 34% of all cases. We found a high prevalence of MSI CRC (43%, 15/35) in the tested Nigerian samples. There were no significant differences in clinicopathological features, including tumor location, between MSI and microsatellite stable (MSS) CRC. Our results are in line with our previous report that found a high prevalence (41%) of MSI CRC in Ghanaian patients. These findings raise important questions about the role of genetic and environmental factors in CRC development in West Africa.

Citation Format: David O. Irabor, Marilena Melas, Stephen B. Gruber, Chanjuan Shi, Leon Raskin. Molecular and clinicopathological features of native Nigerian colorectal cancer [abstract]. In: Proceedings of the AACR International Conference: New Frontiers in Cancer Research; 2017 Jan 18-22; Cape Town, South Africa. Philadelphia (PA): AACR; Cancer Res 2017;77(22 Suppl):Abstract nr A17.

Cancer-associated fibroblasts promote directional cancer cell migration by aligning fibronectin

Cancer-associated fibroblasts (CAFs) are major components of the carcinoma microenvironment that promote tumor progression. However, the mechanisms by which CAFs regulate cancer cell migration are poorly understood. In this study, we show that fibronectin (Fn) assembled by CAFs mediates CAF-cancer cell association and directional migration. Compared with normal fibroblasts, CAFs produce an Fn-rich extracellular matrix with anisotropic fiber orientation, which guides the cancer cells to migrate directionally. CAFs align the Fn matrix by increasing nonmuscle myosin II- and platelet-derived growth factor receptor α-mediated contractility and traction forces, which are transduced to Fn through α5β1 integrin. We further show that prostate cancer cells use αv integrin to migrate efficiently and directionally on CAF-derived matrices. We demonstrate that aligned Fn is a prominent feature of invasion sites in human prostatic and pancreatic carcinoma samples. Collectively, we present a new mechanism by which CAFs organize the Fn matrix and promote directional cancer cell migration.

[Value of spectral CT-based quantitative analysis in differential diagnosis of liver cancer and liver abscess]

Objective: To investigate the value of spectral CT-based quantitative analysis in the differential diagnosis of liver cancer and liver abscess. Methods: A total of 70 patients with space-occupying lesions in the liver(45 with liver cancer and 25 with liver abscess)underwent spectral CT scans to obtain spectral images in the arterial phase and portal venous phase. The solid constituents of lesions and the iodine and water concentrations in necrotic or cystic parts of lesions, normal hepatic tissue, and abdominal aorta in the arterial phase and portal venous phase were measured, and the normalized iodine concentration(NIC)and lesion-to-normal hepatic tissue ratio(LNR)of iodine concentration were calculated. The two samples t-test and the receiver operating characteristic(ROC)curve analysis were performed for the quantitative indices above. Results: The patients with liver cancer had higher NIC and LNR in solid constituents in the arterial phase than those with liver abscess(NIC: 0.15±0.06 mg/ml vs 0.14±0.02 mg/ml, P > 0.05; LNR: 2.78±0.65 vs 1.45±0.88, P < 0.001). The patients with liver abscess had significantly higher NIC and LNR in solid constituents in the portal venous phase than those with liver cancer(NIC: 0.65±0.08 mg/ml vs 0.52±0.08 mg/ml, P≤0.001; LNR: 1.22±0.23 vs 0.95±0.15, P≤0.001). There were no significant differences in NIC in the arterial phase or NIC and LNR in the portal venous phase in necrotic or cystic parts of lesions between the patients with liver cancer and liver abscess(P > 0.05). The optimal quantitative value for the differential diagnosis of liver cancer and liver abscess was LNR in arterial phase, and the cut-off value of 1.53 had a sensitivity of 100% and a specificity of 92%. Conclusion: Quantitative iodine concentration analysis in spectral CT imaging has a certain value in the differential diagnosis of liver cancer and liver abscess and can improve the accuracy of diagnosis.

[The application of captopril challenge test in the diagnosis of primary aldosteronism]

Objective: To evaluate the value of captopril challenge test (CCT) in the diagnosis of primary aldosteronism (PA). Methods: A total of 674 patients [(45.0±13.7) years, men 341, women 333] admitted to Peking Union Medical College Hospital from 2000 to 2015 were analyzed. Among them, 222 subjects were with essential hypertension (EH), 28 were with pheochromocytoma (PHEO), 246 were with idiopathic hyperaldosteronism (IHA) and 178 were with aldosterone producing adenoma (APA). All patients received CCT. 24 h urine sodium was measured in partial patients. Plasma renin activity (PRA), aldosterone (ALD) were detected. Results: Compared with EH [PRA: before 0.5(0.2, 0.9) μg·L(-1)·h(-1,) after 0.8(0.4, 1.5) μg·L(-1)·h(-1;) ALD: before (393±122) pmol/L, after (360±97) pmol/L] and PHEO [PRA: before 0.3(0.1, 0.9) μg·L(-1)·h(-1,) after 0.4(0.1, 1.6) μg·L(-1)·h(-1;) ALD: before (396±108) pmol/L, after (374±114) pmol/L], lower levels of PRA and higher levels of ALD before and after CCT were observed in PA patients [PRA: before 0.1 (0.1, 0.2) μg·L(-1)·h(-1,) after 0.1 (0.1, 0.2) μg·L(-1)·h(-1;) ALD: before (468±216) pmol/L; after (457±199) pmol/L]. After CCT, the suppression rate of ALD [2.8% (-8.8%, 15.4%) vs 6.6% (-4.3%, 17.6%)] and increasing rate of PRA [0(0, 50%) vs 50%(0, 200%)] in PA patients were lower than those in EH patients. The ALD/PRA ratio (ARR) were higher in PA than that in EH or PHEO patients. In the EH subjects, ALD levels of seated posture were higher than those of recumbent posture both before and after receiving captopril, but with no changes in ARR after CCT. No significant differences in ALD and ARR (before and after receiving captopril) were observed between seated and recumbent position in the PA group. The ARR after CCT tended to decrease in EH subjects with elevated urine-sodium compared with those with normal urine-sodium. No changes could be viewed in ALD and PRA levels between normal urine-sodium and elevated urine-sodium groups among APA, IHA and EH patients either before or after CCT. Among patients with APA, the ALD levels before CCT and the ARR after CCT were lower in the patients with AngiotensionⅡ(AngⅡ) reactive than those without. A ROC curve analysis suggested that the optimal cutoff value was 46.2 (ALD unit: ng/dl; PRA unit: μg·L(-1)·h(-1)) for ARR after challenge in diagnosing PA, with the sensitivity of 88.7% and specificity of 84.8%. Conclusions: ARR after 25 mg captopril had high sensitivity and specificity in diagnosis of PA with the cutoff of 46.2. Seated CCT could replace recumbent CCT as a more confirmatory test. The PRA increasing rate should be taken into consideration when diagnosis of PA.

Amino acid and phosphorus digestibility of fermented corn-soybean meal mixed feed with Bacillus subtilis and Enterococcus faecium fed to pigs

In the present study, a 2-stage solid-state fermentation process using followed by was performed with the purpose of improving the nutritional quality of corn and soybean meal (SBM) mixed feed (MF). The matrix of native MF and fermented MF (FMF) was analyzed using scanning electron microscopy to determine external structures after solid-state fermentation. Results of the present study indicated that the FMF had a greater concentration of CP and total P compared with the unfermented feed, whereas the contents of β-conglycinin, glycinin, phytate P, raffinose, stachyose, and NDF in FMF declined by 77.6, 86.7, 41.2, 47.2, 36.6, and 38.9%, respectively. The content of trichloroacetic acid-soluble protein, particularly those of small peptides and free AA, increased more than 3 times after fermentation. Scanning electron microscopy revealed that irregular shapes and a lot of porous structures were observed in the SBM of FMF, the cell wall of corn in FMF was destroyed, and the number of starch granules was decreased after 2-stage fermentation. Two animal experiments were conducted to evaluate the digestibility of CP and P in FMF when fed to pigs. In Exp. 1, 6 barrows (15.20 ± 1.27 kg initial BW) fitted with a T-cannula in the distal ileum were allotted to a replicated 3 × 3 Latin square with 3 diets and 3 periods per square. Two diets containing unfermented MF or FMF as the only source of protein and a N-free diet were formulated. Results indicated that the apparent ileal digestibility (AID) of total AA and Lys in FMF (74.98 and 75.34%) were greater ( < 0.05) than in untreated MF (69.66 and 68.56%). The standard ileal digestibility (SID) of Lys in FMF (82.17%) was also greater ( < 0.05) than in MF (75.91%). In Exp. 2, 16 barrows (17.57 ± 1.08 kg initial BW) were allotted to 2 diets formulated to contain MF or FMF as the sole source of P to determine the digestibility of P. The apparent total tract digestibility and standardized total tract digestibility of P in FMF were 58.14 and 64.72%, respectively. These values were greater ( < 0.01) than in untreated MF (37.11 and 44.89%, respectively). Our results indicate that a solid-state fermentation process using followed by offers an effective approach to improving the quality of corn and SBM MF.

Could the PD-1 Pathway Be a Potential Target for Treating Small Intestinal Adenocarcinoma?

OBJECTIVES

The programmed death 1 (PD-1) pathway is upregulated in the immune microenvironment of many cancers. In this study, we examined the PD-1 pathway and the immune microenvironment of small intestinal adenocarcinomas by immunohistochemistry.

METHODS

From our department pathology archives we identified 42 small intestinal adenocarcinomas from between 2000 and 2015, with blocks available for IHC studies. Tumors were immunohistochemically stained for CD3, CD4, CD8, CD20, PD-1, and programmed death ligand 1 (PD-L1) expression.

RESULTS

PD-1 was expressed by intratumoral and peritumoral lymphocytes in 35 of 42 (83%) cases. PD-L1 expression on tumor cells and immune cells was observed in seven of 42 (17%), and 18 of 42 (43%) cases, respectively. PD-L1 was mainly expressed by histiocytes capping cancerous glands/nests at the invasive front or by most tumor cells in medullary carcinomas. All the PD-L1+ tumors also expressed PD-1. The tumors expressing PD-L1 contained more CD3+, CD4+, and CD8+ T cells, but showed a lower CD4+/CD8+ ratio than those without expression of PD-L1.

CONCLUSIONS

PD-1 and PD-L1 are highly expressed by most small intestinal adenocarcinomas. Blockage of the PD-1 pathway should be evaluated in the treatment of small intestinal adenocarcinomas.

Microsatellite Instability Is Common in Colorectal Cancer in Native Nigerians

BACKGROUND

Colorectal cancer (CRC) is the fifth most common cancer in Africa, with significant differences in incidence, biology and clinical behavior from other populations.

MATERIALS AND METHODS

We studied prevalence and clinicopathological features of microsatellite instability (MSI) and young onset CRC in 83 archival samples from the University of Ibadan, Nigeria.

RESULTS

Nigerian cases of CRC were MSI-high in 43% and MSI-high CRC had significantly lower histological heterogeneity than microsatellite-stable CRC (20% vs. 55% respectively, p=0.046). Presence of signet ring cell differentiation (10-50% of tumor) was significantly higher in younger patients with CRC (<50 years) (odds ratio(OR)=5.93, 95% confidence interval(CI)=1.17-29.95, p=0.038). Poor differentiation (34%), invasive growth (96%), and high prevalence of mucinous (10%) and signet ring cell adenocarcinomas (4%) were among distinct features of Nigerian patients with CRC.

CONCLUSION

MSI-high CRC is more common in West Africa and more detailed molecular and genetic analysis is warranted as CRC incidence and mortality continue to increase in the Sub-Saharan Africa.

Development of Aggressive Pancreatic Ductal Adenocarcinomas Depends on Granulocyte Colony Stimulating Factor Secretion in Carcinoma Cells

The survival rate for pancreatic ductal adenocarcinoma (PDAC) remains low. More therapeutic options to treat this disease are needed, for the current standard of care is ineffective. Using an animal model of aggressive PDAC (Kras/p48^TGFβRIIKO), we discovered an effect of TGFβ signaling in regulation of G-CSF secretion in pancreatic epithelium. Elevated concentrations of G-CSF in PDAC promoted differentiation of Ly6G⁺ cells from progenitors, stimulated IL10 secretion from myeloid cells, and decreased T-cell proliferation via upregulation of Arg, iNOS, VEGF, IL6, and IL1b from CD11b⁺ cells. Deletion of csf3 in PDAC cells or use of a G-CSF-blocking antibody decreased tumor growth. Anti-G-CSF treatment in combination with the DNA synthesis inhibitor gemcitabine reduced tumor size, increased the number of infiltrating T cells, and decreased the number of Ly6G⁺ cells more effectively than gemcitabine alone. Human analysis of human datasets from The Cancer Genome Atlas and tissue microarrays correlated with observations from our mouse model experiments, especially in patients with grade 1, stage II disease. We propose that in aggressive PDAC, elevated G-CSF contributes to tumor progression through promoting increases in infiltration of neutrophil-like cells with high immunosuppressive activity. Such a mechanism provides an avenue for a neoadjuvant therapeutic approach for this devastating disease. Cancer Immunol Res; 5(9); 718-29. ©2017 AACR.

Effects of Lactobacillus rhamnosus GG on the maturation and differentiation of dendritic cells in rotavirus-infected mice

Rotavirus-related diarrhoea is considered one of the most important diseases in field animal production. In addition to the classic vaccine strategy, a number of studies have utilised probiotics, such as Lactobacillus rhamnosus GG (LGG), to prevent rotavirus-induced diarrhoea. Although it has been partially revealed that Toll-like receptors (TLRs) are involved in the LGG-mediated protection against rotavirus infection, the details of the underlying immunologic mechanisms remain largely unknown. In this study, three-to-four-week-old female BALB/c mice were divided into three groups and orally administered phosphate buffered saline (PBS), PBS plus rotavirus or LGG plus rotavirus, respectively. The differentiation and maturation of dendritic cells (DCs) were then determined by FACS, the expression levels of TLR-3 and nuclear factor kappa beta (NF-κB) were evaluated using real time PCR, and the production of inflammatory cytokines in mesenteric lymph nodes (MLNs) were determined by ELISA. The results demonstrated that rotavirus infection significantly increased the percentage of CD11c⁺CD11b⁺CD8a^- DCs and decreased the percentage of CD11c⁺CD11b^-CD8a⁺ DCs in MLNs. By contrast, the presence of LGG significantly decreased the percentage of CD11c⁺CD11b⁺CD8a^- DCs and increased the percentage of CD11c⁺CD11b^-CD8a⁺ DCs, which indicates that the differentiation of DCs is involved in the protective effects of LGG. Rotavirus infection also resulted in the increased expression of surface markers such as CD40, CD80 and MHC-II in DCs, and the administration of LGG significantly increased the expression level further. The mRNA levels of TLR-3 and NF-κB in the intestine and MLNs were also significantly increased in the presence of rotavirus, which was further increased in the presence of LGG. The production of inflammatory cytokines was also determined, and the results showed that rotavirus caused the increased production of interleukin (IL)-12 and tumour necrosis factor alpha; this effect was further enhanced by LGG. Meanwhile, although rotavirus infection led to the increased production of IL-6 and IL-10, the presence of LGG significantly decreased the mRNA levels of these cytokines. By contrast, rotavirus infection resulted in the decreased production of interferon gamma (IFN-γ), and the administration of LGG significantly increased the levels of IFN-γ. Taken together, the protective effects of LGG were partially due to the modulation of the differentiation and maturation of DCs, the increased production of TLR-3 and NF-κB, and the modulation of inflammatory cytokines.

Abstract 588: Advanced molecular characterization of severe autoimmune toxicities associated with checkpoint inhibitor therapies

Immune checkpoint inhibitors (ICIs) have made a profound impact on the treatment of a variety of cancers. However, as with any systemic treatment, toxicities are inevitable. With most classes of cancer therapies, toxicities are relatively predictable based on clinical trial safety data and therefore can be handled with prophylactic or supportive care measures. However, ICIs are unique in their ability to cause rare but severe auto-immune toxicities. The molecular underpinnings of these toxicities, as well as unique features of the patient, tumor, or affected tissue, have not been extensively explored. We recently reported a small case series of two patients with myocarditis resulting in death arising following combination ICI therapy (Johnson et al, N Engl J Med, 2016). High lymphocytic infiltration, coupled with PD-L1 expression was present in the affected myocardium and skeletal muscle. Common T cell clones were identified between the affected tissue and tumor, and abnormal expression of muscle-specific transcripts was identified in the associated tumor, suggesting release of peripheral tolerance to tumor-expressed self-antigens.To expand upon our reported study, we collected healthy and afflicted tissue from a series of cancer patients with immune-related colitis, myocarditis (MC), and encephalopathy following ICI treatment. We hypothesize that molecular analysis of these tissues will identify causal factors in the etiology of these toxicities, and how to better predict, prevent, and treat them. Thus, we performed molecular characterization of the immune infiltrate and diseased tissue microenvironment. A total of 20 affected (colon, cardiac, brain) and non-diseased control specimens were examined by spatial digital profiling (nanoString). This process generates a spatial heatmap of digital counts of 20 selected immunology and cellular markers and proteins across each specimen. Using this technology, the landscape of inflammation in ICI-affected organs can be resolved for insights into the mechanism whereby ICI-mediated auto-immunity occurs. Targeted RNAseq for selected immuno-oncology mRNA targets was also performed. In initial RNA sequencing analyses of MC cases, affected myocardium, skeletal muscle, and patient-matched tumors all demonstrated expression of immune activation markers (e.g. interferon-gamma and granzyme B), expression of PD-L1, and muscle-specific genes. In the expanded population, including colitis, digital spatial profiling analyses and targeted NGS (RNAseq) are underway. Although data analyses are incomplete at the time of this abstract, this work will be the largest and most comprehensive analysis of the molecular underpinnings of ICI-mediated auto-immune toxicity reported to date. These data should offer clarity in the mechanisms and features of these adverse events, how to prevent or predict them with precision medicine, and how to treat them when they do occur.

Citation Format: Justin M. Balko, Daniel Y. Wang, Yu Wang, Rami Al-Rohil, Margaret Compton, Jeffery A. Sosman, Igor Puzanov, Bret Mobley, Robert D. Hoffman, Yaomin Xu, Javid J. Moslehi, Chanjuan Shi, Douglas B. Johnson. Advanced molecular characterization of severe autoimmune toxicities associated with checkpoint inhibitor therapies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 588. doi:10.1158/1538-7445.AM2017-588

[The impact of cigarette cessation intervention on mental state of patients with coronary heart disease]

Objective: This study was designed to observe the impact of cigarette cessation on anxiety and depression in patients with coronary heart disease (CHD). Methods: A total of 690 cigarette smoking patients with CHD identified by coronary angiography (CAG) were included and analyzed in the study.The mental state were scored with Hamilton anxiety (HAMA) and depression (HAMD) scale both on admission and at 6-month follow-up.The patients were divided into two groups based on the cigarette cessation.The score of mental state between the two groups were compared.The patients were treated with percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG), or medicine therapy (MT). Results: The clinic data and score of mental state were similar at the time of admission (HAMA: 10.66±5.53 vs 11.09±5.61, P=0.311; HAMD: 29.81±10.13 vs 28.94±10.22, P=0.266 4) between the two groups.After 6 months, the proportions of subjects in smoking cession group with anxiety (24.2% vs 32.3%, P<0.05), depression (18.0% vs 27.5%, P<0.05), and anxiety and depression (7.0% vs 16.2%, P<0.001) decreased significantly compared with those in smoking group irrespective of the treatment strategy.Both the HAMA and HAMD scores were lower in smoking cessation group (HAMA: 9.83±3.40; HAMD: 24.91±7.90) than in smoking group (HAMA: 10.98±4.87; HAMD: 27.70±11.16) (all P<0.001). Conclusions: Smoking cessation is good for the relief of anxiety and depression in CHD patient.

Alleviation of enterotoxigenic Escherichia coli challenge by recombinant Lactobacillus plantarum expressing a FaeG- and DC-targeting peptide fusion protein

FaeG is the major subunit of K88 fimbriae. These cell surface attachments are considered to be the major virulence factor of enterotoxigenic Escherichia coli (ETEC), which causes diarrhoea in piglets. The use of dendritic cell-targeting peptide (DCpep) has been demonstrated to be an effective approach to enhance the immunity of vaccines. Lactobacillus plantarum is an attractive candidate for oral vaccination owing to its beneficial effects and safety. In this study, L. plantarum was employed to deliver a FaeG-DCpep fusion antigen, and the immune response in mice was evaluated. The synthesis of FaeG-DCpep dramatically increased the adhesion of recombinant L. plantarum (RLP) to IPEC-J2 cell surfaces, resulting in direct competition between L. plantarum and ETEC during adhesion assays. Significantly higher levels of body weight gain, sera immunoglobulin G and intestinal immunoglobulin A were observed in BALB/c mice immunised with RLP. In addition, the number of CD19+ B cells and CD11c+DC cells and the expression levels of several cytokines in the spleen and lymph nodes increased significantly compared to non-immunised mice. The oral administration of RLP also alleviated the symptoms of ETEC challenge, as shown by haematoxylin-eosin staining, indicating that RLP may be an efficient vaccine candidate.

Molecular characterization of immune-related severe adverse events (irSAE)

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Background: Immune checkpoint inhibitors (ICIs; anti-CTLA-4 and anti-PD-1) have shown clinical success in many cancers, but may cause rare irSAE. The molecular features of irSAE have not been extensively explored. Therefore, we characterized the immune composition of tissue affected by ICI-mediated inflammation with a focus on colitis and neurologic toxicity. Methods: We performed retrospective T-cell receptor (TCRβ) sequencing, RNA-sequencing (HTG EdgeSeq; > 2500 immune-related genes), and digital spatial profiling (NanoString) for 20 protein markers in 10 regions across tissues representing ICI-induced colitis, autoimmune inflammation (e.g. Crohn’s) and normal colon. Matched tumors were also included in a subset. We also analyzed the encephalitic and healthy brain of a unique presentation of anti-PD-1-induced encephalitis. Results: Patient-matched melanoma and colitis biopsies (n = 3) demonstrated shared T cell clones in all samples ranging from several shared clones to several hundred (0.4%, 2.7%, and 3% of rearrangements, respectively), including high-frequency clones. Shared TCRβ sequences were also identified among and between colon-irSAE and Crohn’s specimens. Gene expression patterns of inflammation in colon-irSAE resembled that of Crohn’s disease in principle components and clustering analysis, highlighting likeness between these diseases/SAEs. NanoString digital spatial profiling of regions of inflammation across samples showed higher CD68 and PD-L1 positivity in colon-irSAE specimens versus normal colon or Crohn’s specimens and reduced beta-catenin levels in both Crohn’s and colon-irSAE specimens relative to normal controls. Finally, we detected a high degree of TCR clonality in the encephalitic brain, including a single sequence present in ~20% of > 12,000 T cells, suggesting a distinct antigen-specific response. Conclusions: We report the molecular characteristics of irSAE in colon and brain specimens from patients receiving ICIs. Highly clonal TCRβ sequences were frequently detected, particularly in a unique case of encephalitis-irSAE. Furthermore, we identify molecular distinctions and similarities between autoimmune and colon-irSAEs at the gene expression and proteomic levels.

The Effects of Lentivirus-mediated shRNA Interference Targeting Mcl-1 on Growth of NK/T-cell Lymphoma

Myeloid leukemia-1 (Mcl-1) gene has been reported as an important factor in various types of cancer, but little research was processed on natural killer (NK)/T-cell lymphoma, a kind of a highly aggressive disease with a poor prognosis. Here we investigated the expression of Mcl-1 in seven lymphoma cell lines and its potential role as a molecular drug target for NK/T-cell lymphoma therapy by using lentivirus-mediated shRNA interference targeting Mcl-1 (lenti-shMcl-1). In our study, the expression of Mcl-1 in different lymphoma cell lines were evaluated firstly, after that lenti-shMcl-1 was constructed and transduced into NK/T-cell lymphoma cell line SNK-6 which had a high level expression of Mcl-1. Methylthiazolete-Trazolium (MTT) assay and flow cytometry (FCA) were employed to detect the status of proliferation and apoptosis after infection. Lastly we investigated the effects of chemotherapy agent vincristine (VCR) combination with lenti-shMcl-1 by MTT and FCA assay. The results showed that Mcl-1 gene expressed in all seven lymphoma cell lines at different levels. Recombinant lentiviruses could infect SNK-6 cells effectively. Mcl-1 expression level was remarkably down-regulated after infection with lenti-shMcl-1. The growth of SNK-6 cells was inhibited significantly through apoptosis pathway. Otherwise, lenti-shMcl-1 also revealed a significant chemosensitizing effect in combination with vincristine. In a word, we demonstrated that lenti-shMcl-1 had a significant anti-NK/T cell lymphoma effect and targeting Mcl-1 therapy could be a promising novel approach in treatment of lymphoma.