Surgical and Molecular Pathology of Barrett Esophagus

BACKGROUND

Patients with Barrett esophagus (BE) are predisposed to developing dysplasia and cancer. Adenocarcinoma, which is associated with BE, is the most common type of esophageal tumor and, typically, it has an aggressive clinical course and a high rate of mortality.

METHODS

The English-language literature relating to tumor epidemiology, etiology, and the pathogenesis of BE was reviewed and summarized.

RESULTS

The role of pathologists in the diagnosis and pitfalls associated with grading Barrett dysplasia is addressed. Current molecular testing for Barrett neoplasia, as well as testing methods currently in development, is discussed, focusing on relevant tests for diagnosing tumor types, determining prognosis, and assessing therapeutic response.

CONCLUSIONS

Grading is essential for developing appropriate treatment plans, follow-up visits, and therapeutic interventions for each patient. Familiarity with current molecular testing methods will help physicians correctly diagnose the disease and select the most appropriate therapy for each of their patients.

Selective Nuclear Export Inhibitor KPT-330 Enhances the Antitumor Activity of Gemcitabine in Human Pancreatic Cancer

Pancreatic cancer is an aggressive and deadly malignancy responsible for the death of over 37,000 Americans each year. Gemcitabine-based therapy is the standard treatment for pancreatic cancer but has limited efficacy due to chemoresistance. In this study, we evaluated the in vitro and in vivo effects of gemcitabine combined with the selective nuclear export (CRM1) inhibitor KPT-330 on pancreatic cancer growth. Human pancreatic cancer MiaPaCa-2 and metastatic pancreatic cancer L3.6pl cell lines were treated with different concentrations of KPT-330 and gemcitabine alone or in combination, and anchorage-dependent/independent growth was recorded. In addition, L3.6pl cells with luciferase were injected orthotopically into the pancreas of athymic nude mice, which were treated with (i) vehicle (PBS 1 mL/kg i.p., 2/week and povidone/pluronic F68 1 mL/kg p.o., 3/week), (ii) KPT-330 (20 mg/kg p.o., 3/week), (iii) gemcitabine (100 mg/kg i.p., 2/week), or (iv) KPT-330 (10 mg/kg) + gemcitabine (50 mg/kg) for 4 weeks. KPT-330 and gemcitabine alone dose-dependently inhibited anchorage-dependent growth in vitro and tumor volume in vivo compared with vehicle treatment. However, the combination inhibited growth synergistically. In combination, KPT-330 and gemcitabine acted synergistically to enhance pancreatic cancer cell death greater than each single-agent therapy. Mechanistically, KPT-330 and gemcitabine promoted apoptosis, induced p27, depleted survivin, and inhibited accumulation of DNA repair proteins. Together, our data suggest that KPT-330 potentiates the antitumor activity of gemcitabine in human pancreatic cancer through inhibition of tumor growth, depletion of the antiapoptotic proteins, and induction of apoptosis.

Prognostic value of tumor-infiltrating lymphocytes (TILs) and expression of PD-L1 in cholangiocarcinoma

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Background: Cholangiocarcinoma is a malignancy arising from the epithelial cells of the biliary tract with poor prognosis. Tumor-infiltrating lymphocytes (TILs) have a prognostic impact in various solid tumors. We aimed to investigate TIL expression and programmed cell death ligand PD-L1 and their clinical relevance in cholangiocarcinoma. Methods: Formalin-fixed paraffin-embedded tumor samples from thirty seven patients with resected and histologically verified cholangiocarcinoma between 1990 and 2011 were identified and immunohistochemically (IHC) stained with anti CD8, anti CD45RO and the anti-PDL1 mouseIgG1 (clone 5H1; Thompson) antibodies on a Leica automated IHC platform. The stains were semiquantitatively analyzed using the AllRed score system (range 1 to 8). Cases with IHC score > 3 were considered positive. The association between PDL1, CD45R0, overall survival (OS) and progressive free survival (PFS) was investigated using Kaplan-Meier survival and COX proportional hazard regression analyses. Results: The median age of patients was 64 (41-85) with 51% male. 25%, 59%, 10% and 5% were stage I, II, III, and IV respectively. CD8 was positive in 10/37 (27%) with median IHC of 5, CD45R0 (specimen with lymph node like structure) was positive in 16/37 (43%) with median IHC score of 4, PD-L1 was positive in 35/37 (94 %) with median IHC score of 8. Pts with tumors exhibiting lymph node (LN) like structures (CD45RO+) has better median OS (63 months vs 18 months, P = 0.0065) and median PFS (29 months vs 14.6 months, P = 0.05) than patients lacking LN like structures (CD45RO-). 5 yrs. OS in CD45RO+ was 64% vs 20% in CD45RO- (P 0.006) whereas 5 yrs. PFS in CD45RO+ was 41% vs. 8% in in CD45RO- pts (P value 0.05). Correlating PDL1 with OS and PFS was not done due to high expression of PD-L1 in most of the samples (94%). Conclusions: Presence of lymph node like structures (CD45RO+) was associated with significant better outcome reflecting the immune-mediated killing of tumor cells. The high expression of PD-L1 on cholangiocarcinoma cells represents a potential therapeutic target which may improve the prognosis for this dismal cancer. Future trials involving PD-L1 inhibitors in cholangiocarcinoma are warranted.

Alcohol, HIV/AIDS, and Liver Disease

Globally, there are over 33 million persons living with HIV/AIDS resulting in 1.8 million deaths annually. While the rate of HIV transmission is slowing, it is estimated that 2.6 million new infections occur yearly [1]. In the United States, there are approximately 1.2 million living with HIV/AIDS, with 50,000 new HIV infections and 17,000 deaths from the disease annually [2]. For those who can obtain effective antiretroviral therapy (ART), HIV/AIDS has become a chronic disease with life expectancies over 30 years [3]. Research in the last 10 years has revealed the importance of alcohol in the HIV/AIDS epidemic. Alcohol use, in moderate or hazardous amounts, has been associated with increased acquisition of HIV infection, progression of HIV infection, deleterious effects on HIV treatment, and acceleration in the comorbidities of HIV infection [4–9]. Yet alcohol remains the “forgotten drug” of the HIV/AIDS epidemic [10].

Leptin's regulation of obesity-induced cardiac extracellular matrix remodeling

Obesity-induced remodeling of cardiac extracellular matrix (ECM) leads to myocardial fibrosis and ultimately diastolic dysfunction. Leptin, an adipocyte hormone, is emerging as a novel mechanistic link between obesity and heart diseases. Despite the known essential role of leptin in hepatic and renal fibrosis, the in vivo effects of leptin on cardiac ECM remodeling remain unclear. Our objective was to define the role of leptin as a key mediator of pro-fibrogenic responses in the heart. In vitro administration of leptin to primary cardiofibroblasts resulted in significant stimulation of pro-collagen Iα ( 1 ) and a decrease in pro-matrix metalloproteinase (MMP)-8, -9 and -13 gene expressions at 24 h. To study the in vivo pro-fibrotic effect, leptin was administrated to C57BL/6 and leptin-deficient ob/ob mice for 8 weeks. With exogenous leptin ob/ob mice displayed passive diastolic filling dysfunction, coincided with significant increase in myocardial collagen compared with ob/ob controls. We also observed a marked stimulation of pro-collagen IIIα ( 1 ) and suppression of pro-MMP-8, TIMP-1 and -3 gene expressions in leptin-treated ob/ob mice. Our findings suggest pro-fibrotic effects of leptin in the heart, primarily through the predominance of collagen synthesis over degradation.

T lymphocyte regulation of lysyl oxidase in diet-induced cardiac fibrosis

Left ventricular diastolic dysfunction is an important predictor of prognosis and mortality of heart failure. Increased left ventricular stiffness can be associated with excessive myocardial fibrosis and increased cross-linked collagen by the enzyme lysyl oxidase (LOX). These cardiac extracellular matrix (ECM) remodeling processes are affected by T-lymphocyte function and phenotype. We sought to examine the role of T lymphocytes in myocardial LOX regulation in diet-induced fibrotic hearts. Female SCID mice, devoid of functional T lymphocytes, and wild-type (WT) C57BL/6 were treated with a high-fat high-simple carbohydrate (HFHSC) diet for 12 months. HFHSC-fed WT mice demonstrated a significant increase in the catalytic activity of myocardial LOX compared with respective controls. These changes coincided with a marked increase in ECM collagen cross-linking and impaired diastolic filling pattern. However, induction of LOX was minimal in the SCID mice compared with the WT group. Correspondingly fibrillar cross-linked collagen concentrations and diastolic dysfunction were less prominent in the SCID mice compared with the WT group. Our results suggest a role for T lymphocytes in this dietary induction of diastolic dysfunction through modulation of LOX-dependent collagen maturation.

Myocardial lysyl oxidase regulation of cardiac remodeling in a murine model of diet-induced metabolic syndrome

Metabolic syndrome (MetS) represents an increased risk of cardiovascular disease. Although its individual components adversely affect cardiac structure and function, the extent to which multiple components of MetS affect the cardiac extracellular matrix (ECM) has not been well characterized. Lysyl oxidase (LOX) is one of the cardiac ECM-modifying enzymes that catalyze the formation of collagen cross-linking. Our objective was to define the effect of diet-induced MetS on the LOX enzyme. MetS was induced in male C57BL/6 mice by administrating a high-fat, high-simple carbohydrate diet for 6 mo. Gene expression was determined by real-time PCR. The cardiac protein expression and enzymatic activity of LOX were measured. The severity of fibrosis was assessed by histology and hydroxylproline assay. Cardiac diastolic function was assessed by in vivo analysis of the pressure-volume relationship. LOX, matrix metalloproteinases, and their tissue inhibitors were analyzed, and of these three, LOX was most significantly changed in the MetS mice. Despite the blunted gene expression of LOX isoforms, MetS mice demonstrated a significant upregulation of bone morphogenetic protein-1. Correspondingly, there was an increase in the ratio of protein expression of mature to proenzyme LOX by 25.9%, enhanced LOX activity by 50.0%, and increased cardiac cross-linked collagen compared with the controls. This fibrotic response coincided with a marked increase in end-diastolic pressure, increased left ventricular stiffness, and impaired diastolic filling pattern. Our data signify that diet-induced MetS alters the remodeling enzymes, mainly LOX, thereby altering ECM structure by increasing the amount of cross-linking and inducing diastolic dysfunction.

Oral administration of the purple passion fruit peel extract reduces wheeze and cough and improves shortness of breath in adults with asthma

Asthma, affecting as many as 400 million individuals worldwide, is one of the most prevalent chronic health condition in the United States. With an increasing number of patients with asthma and the frequent inability of conventional lifestyle modification and therapy to effectively control the problem, nutritional and dietary therapies are being sought. This study was undertaken to investigate the efficacy of the purple passion fruit peel (PFP) extract, a novel mixture of bioflavonoids, on asthma symptoms. Patients with asthma were studied in a 4-week randomized, placebo-controlled, double-blind trial with oral administration of PFP extract (150 mg/d) or placebo pills. The effects of PFP extract were evaluated by assessing the clinical symptoms of asthma and spirometry tests. Most clinical symptoms of asthma of the PFP extract-treated group were moderated significantly compared to the baseline. The prevalence of wheeze, cough, as well as shortness of breath was reduced significantly in group treated with PFP extract (P < .05), whereas the placebo caused no significant improvement. Purple passion fruit peel extract supplementation resulted in a marked increase in forced vital capacity (P < .05) as placebo showed no effect. However, no significant improvement was observed in the forced expiratory volume at 1 second of those supplemented with PFP extract. No adverse effect was reported by any of study participants. The PFP extract may be safely offered to asthmatic subjects as an alternative treatment option to reduce clinical symptoms.

Reduction of cardiovascular risk factors in subjects with type 2 diabetes by Pycnogenol supplementation

Patients with type 2 diabetes are at considerable risk of excessive morbidity and mortality from cardiovascular disease (CVD). We investigated the clinical effectiveness of Pycnogenol, a flavonoid-rich dietary supplement, in reducing antihypertensive medication use and CVD risk factors in subjects with type 2 diabetes. Forty-eight individuals were enrolled in a randomized, double-blind, placebo-controlled trial with parallel-group design. Patients were diagnosed with both type 2 diabetes and mild to moderate hypertension and were undergoing treatment with angiotensin-converting enzyme (ACE) inhibitors. Subjects were randomly assigned to receive either Pycnogenol pill (125 mg daily) or matched placebo for 12 weeks. According to the values of blood pressure (BP) measured at 2-week intervals, the pretrial ACE inhibitor dosage was left unchanged, reduced by 50%, or brought back to the pretrial dosage until a stable BP was obtained. Fasting plasma glucose, low-density lipoprotein (LDL) cholesterol, glycosylated hemoglobin (HbA1c), serum endothelin-1, and urinary albumin were evaluated monthly. Pycnogenol treatment achieved BP control in 58.3% of subjects at the end of the 12 weeks with 50% reduction in individual pretrial dose of ACE-inhibitors (P <.05). Plasma endothelin-1 decreased by 3.9 pg/mL in Pycnogenol-treated group vs 0.5 pg/mL increase in control group (P < .001). Mean HbA1c dropped by 0.8% in Pycnogenol-treated group (P < .05), whereas it decreased by 0.1% in control group. Fasting plasma glucose declined by 23.7 mg/dL in Pycnogenol-treated group vs 5.7 mg/dL in control group (P < .0001). Low-density lipoprotein cholesterol improved significantly in Pycnogenol-treated group, declining by 12.7 mg/dL (P < .001). A significant decrease in urinary albumin level was observed at week 8 compared with the control group (P < .05). However, this reduction was not significant at 12th week. After 12 weeks of supplementation, Pycnogenol resulted in improved diabetes control, lowered CVD risk factors, and reduced antihypertensive medicine use vs controls.

Impact of Pycnogenol® on cardiac extracellular matrix remodeling induced by l-NAME administration to old mice

Cardiac remodeling is a determinant of the clinical progression of heart failure and now slowing or reversing remodeling is considered as a potential therapeutic target in heart failure. Pycnogenol has been reported to mediate a number of beneficial effects in the cardiovascular system but its effects on hemodynamic and functional cardiovascular changes following cardiac remodeling have not been elucidated. Therefore, we investigated the influence of Pycnogenol supplementation (30 mg/kg) on left ventricular function and myocardial extracellular matrix composition in old C57BL/6N mice following induction of cardiac remodeling by chronic nitric oxide synthase blockade by NG-nitro-L-arginine methyl ester (L-NAME) administration. L-NAME-treated mice demonstrated dilated cardiomyopathy at compensated state, associated with a significant increase of pro-matrix metalloproteinase (MMP)-9 gene expression and activity, a marked decrease in pro-collagen IIIalpha1 gene expression, and a subsequent reduction in cardiac total and cross-linked collagen content. Upon supplementation with Pycnogenol in L-NAME-exposed mice, cardiac gene expression patterns for pro-MMP-2, -9, and -13, and MMP-9 activity were significantly decreased, associated with a significant increase in cardiac tissue inhibitor of metalloproteinase (TIMP)-4 expression. These findings were coincided with a marked increase in myocardial total and cross-linked collagen content, compared with L-NAME-only-treated mice. Moreover, Pycnogenol treatment was associated with reversal of L-NAME-induced alternations in hemodynamic parameters. These data indicate that Pycnogenol can prevent adverse myocardial remodeling induced by L-NAME, through modulating TIMP and MMPs gene expression, MMPs activity, and further reduction in myocardial collagen degradation rate.

Nutritional regulation of immunosenescence for heart health

Immunosenescence via increased inflammatory cytokines may play key regulatory roles in facilitating cardiac infections and heart failure. Based upon recent evidence, we hypothesize that cytokine polarization due to aging directly dysregulates fibroblasts, leading to altered cardiac structure and dysfunction. Some dietary fatty acids should ameliorate heightened inflammatory cytokines thereby retarding cardiac pathology, loss of structural collagen and premature death from heart failure. For example, T-helper (Th) 2 cells' cytokine levels are very high in seniors who have increased heart disease due to suppressed resistance to cardiotrophic pathogens. In addition, such inflammatory cytokines deregulate fibroblasts, thus reducing collagen synthesis, weakening muscle structure and heart pump function for heart failure and hypertension. Therefore, supplementation with n-3 polyunsaturated fatty (PUFA) or conjugated linoleic acids, by reducing Th2 and increasing Th1 cytokines, may provide a sensible and widely available means to treat and even prevent excessive inflammatory cytokines and their cardiotoxic effects. On the other hand, dietary n-6 PUFA may promote cytokine polarization in seniors, exacerbating age-related heart dysfunction.