Hepatic alcohol dehydrogenase deficiency induces pancreatic injury in chronic ethanol feeding model of deer mice.

The single most common cause of chronic pancreatitis (CP, a serious inflammatory disease) is chronic alcohol abuse, which impairs hepatic alcohol dehydrogenase (ADH, a major ethanol oxidizing enzyme). Previously, we found ~5 fold greater fatty acid ethyl esters (FAEEs), and injury in the pancreas of hepatic ADH deficient (ADH-) vs. hepatic normal ADH (ADH+) deer mice fed 3.5g% ethanol via liquid diet daily for two months. Therefore, progression of ethanol-induced pancreatic injury was determined in ADH- deer mice fed ethanol for four months to delineate the mechanism and metabolic basis of alcoholic chronic pancreatitis (ACP). In addition to a substantially increased blood alcohol concentration and plasma FAEEs, significant degenerative changes, including atrophy and loss of acinar cells in some areas, ultrastructural changes evident by such features as swelling and disintegration of endoplasmic reticulum (ER) cisternae and ER stress were observed in the pancreas of ethanol-fed ADH- deer mice vs. ADH+ deer mice. These changes are consistent with noted increases in pancreatic injury markers (plasma lipase, pancreatic trypsinogen activation peptide, FAEE synthase and cathepsin B) in ethanol-fed ADH- deer mice. Most importantly, an increased levels of pancreatic glucose regulated protein (GRP) 78 (a prominent ER stress marker) were found to be closely associated with increased phosphorylated eukaryotic initiation factor (eIF) 2α signaling molecule in PKR-like ER kinase branch of unfolded protein response (UPR) as compared to X box binding protein 1S and activating transcription factor (ATF)6 - 50kDa protein of inositol requiring enzyme 1α and ATF6 branches of UPR, respectively, in ethanol-fed ADH- vs. ADH+ deer mice. These results along with findings on plasma FAEEs, and pancreatic histology and injury markers suggest a metabolic basis of ethanol-induced pancreatic injury, and provide new avenues to understand metabolic basis and molecular mechanism of ACP.

Helicobacter pylori cag pathogenicity island's role in B7-H1 induction and immune evasion.

During Helicobacter pylori (H. pylori) infection CD4+ T cells in the gastric lamina propria are hyporesponsive and polarized by Th1/Th17 cell responses controlled by Treg cells. We have previously shown that H. pylori upregulates B7-H1 expression on GEC, which, in turn, suppress T cell proliferation, effector function, and induce Treg cells in vitro. In this study, we investigated the underlying mechanisms and the functional relevance of B7-H1 induction by H. pylori infection to chronic infection. Using H. pylori wild type (WT), cag pathogenicity island (cag PAI-) and cagA- isogenic mutant strains we demonstrated that H. pylori requires its type 4 secretion system (T4SS) as well as its effector protein CagA and peptidoglycan (PG) fragments for B7-H1 upregulation on GEC. Our study also showed that H. pylori uses the p38 MAPK pathway to upregulate B7-H1 expression in GEC. In vivo confirmation was obtained when infection of C57BL/6 mice with H. pylori PMSS1 strain, which has a functional T4SS delivery system, but not with H. pylori SS1 strain lacking a functional T4SS, led to a strong upregulation of B7-H1 expression in the gastric mucosa, increased bacterial load, induction of Treg cells in the stomach, increased IL-10 in the serum. Interestingly, B7-H1-/- mice showed less Treg cells and reduced bacterial loads after infection. These studies demonstrate how H. pylori T4SS components activate the p38 MAPK pathway, upregulate B7-H1 expression by GEC, and cause Treg cell induction; thus, contribute to establishing a persistent infection characteristic of H. pylori.

Prognostic significance of peritumoral lymphatic vessel density and vascular endothelial growth factor receptor 3 in invasive squamous cell cervical cancer.

Cervical cancer is known to metastasize primarily by the lymphatic system. Dissemination through lymphatic vessels represents an early step in regional tumor progression, and the presence of lymphatic metastasis is associated with a poor prognosis. In patients who have undergone a radical hysterectomy, lymphovascular space invasion (LVSI), assessed on hematoxylin and eosin-stained slides, is a major factor for adjuvant therapy in patients with cervical cancer. With the advent of a lymphatic endothelial cell-specific marker, such as D2-40, it is now possible to distinguish between blood and lymphatic space invasion (LSI). In this study, the utility of D2-40 was assessed for the detection of lymphatic vessel density (LVD) and identification of LSI. The expressions of vascular endothelial growth factor receptor-3 (VEGFR-3), VEGF-C, tyrosine receptor kinase-2, and angiopoietin-1 were assessed by immunohistochemical methods on 50 patients with squamous cell carcinoma of the cervix. Clinicopathologic characteristics, including pelvic lymph node metastasis, were correlated with the above histochemical findings. We found that lymphangiogenesis, measured by an increase in peritumoral LVD, was significantly associated with positive lymph node status (P < .005). VEGFR-3 expression was significantly associated with LVD (P < .05). D2-40 staining verified LSI (P = .03) and surpassed that of hematoxylin and eosin-identified LVSI (P = .54). In conclusion, lymphangiogenic markers, specifically LVD quantified by D2-40 and VEGFR-3, are independently associated with LSI and lymph node metastasis in patients with early squamous cell carcinoma of the cervix treated with radical hysterectomy and pelvic lymphadenectomy.

Novel expression patterns of PI3K/Akt/mTOR signaling pathway components in colorectal cancer.

BACKGROUND: The phosphatidylinositol 3-kinase/Akt/mammalian target of rapamycin (PI3K/Akt/mTOR) pathway plays a critical role in the growth and progression of colorectal cancer (CRC). The purpose of our study was 2-fold: (1) to determine the expression levels of several key components of this pathway, including p85alpha, Akt1, Akt2, p-mTOR(Ser2448), and p-p70S6K(Thr389) in CRCs; and (2) to correlate the expression of these proteins with cancer stage and location (left versus right side). STUDY DESIGN: Immunohistochemistry for p85alpha, Akt1, Akt2, p-mTOR(Ser2448), and p-p70S6K(Thr389) was performed on normal colon and CRCs from 154 patients. RESULTS: All proteins investigated were significantly overexpressed in CRCs compared with matched normal colonic tissue from the same patient (p < 0.0001). PI3K pathway component proteins were moderately correlated across normal and malignant colon tissues; correlations tended to be stronger in normal tissues as compared with the same correlations in cancers. Expression levels of p85alpha were significantly higher in stage IV cancers than in stage I to III cancers (p = 0.0005). p85alpha expression was also significantly increased in the adjacent normal colonic mucosa of patients with stage IV CRC compared with earlier stages (p = 0.003). Finally, expression of Akt1, Akt2, and p-p70S6K(Thr389) was higher in left-sided CRCs compared with CRCs in the right colon (p = 0.007, p = 0.0008, and p = 0.04, respectively). CONCLUSIONS: The PI3K/Akt/mTOR pathway components, p85alpha, Akt1, Akt2, p-mTOR(Ser2448), and p-p70S6K(Thr389) are highly overexpressed in CRCs, providing the rationale for targeting this pathway therapeutically in CRC patients. The increased expression of p85alpha in the adjacent normal mucosa of stage IV patients suggests an important field defect, which may contribute to the growth and progression of these cancers.

Reduced CD1d expression in colonic epithelium in microscopic colitis.

CD1d is a member of a major histocompatibility complex class I-like molecule family. Its function may involve presenting microbial nonpeptide or lipidic antigens to T lymphocytes, therefore to serve as an important factor in normal mucosal immunity of the gastrointestinal tract. In this study, the expression level of CD1d in microscopic colitis (ie, collagenous and lymphocytic colitis) was examined, and compared with that in normal colonic mucosa. Formalin-fixed, paraffin-embedded colon biopsies with diagnosis of lymphocytic colitis (19 cases), collagenous colitis (6 cases), and no pathologic change (20 cases) were studied immunohistochemically using monoclonal antibodies against human CD1d, CD3, CD4, and CD8. CD1d staining in the epithelium and lamina propria was graded along a scale of 0 to 4. Intraepithelial CD3-positive lymphocytes were counted in an area of 300 epithelial cells for each specimen. The results show that CD1d was expressed in normal colonic epithelial cells, primarily on the basolateral membranes with a concentrated intracellular pool in the subnuclear region. The expression level was markedly reduced in both lymphocytic colitis (P<0.001) and collagenous colitis (P<0.001), along with a significant increase in the number of intraepithelial CD3/CD8 lymphocytes (P<0.001). These findings suggest that microscopic colitis is associated with decreased epithelial expression of CD1d, an important immunoregulatory molecule in the gastrointestinal tract.

A rapid and noninvasive method for detecting tissue-limited mosaicism: detection of i(12)(p10) in buccal smear from a child with Pallister-Killian syndrome.

Pallister-Killian syndrome (PKS), a rare disorder, is characterized by tissue-limited or tissue-specific mosaicism. The characteristic chromosome abnormality associated with PKS is i(12p), which is seen predominantly in skin fibroblast cultures. Diagnosis of i(12p) has been carried out on buccal smears before and was shown to be an easy and feasible method. All previously published studies used alpha-satellite probes for the diagnosis and as such have several pitfalls. Our approach, using dual-color, locus-specific probes, has high specificity and sensitivity for the diagnosis of i(12p). Using statistical analysis, we have also confirmed that the signal pattern in interphase nuclei is consistent with isochromosome 12p.

Pulmonary hypertension in sickle cell hemoglobinopathy: a clinicopathologic study of 20 cases.

Pulmonary hypertension is one of the major causes of morbidity and mortality of patients with sickle cell hemoglobinopathy (SCH). Although a clinically recognized complication of sickle cell disease (SCD), there are few published pathologic studies of pulmonary findings in these patients. The aim of this study was to define the pulmonary pathologic changes and to investigate correlation between the pathologic changes, the antemortem diagnosis of pulmonary hypertension, and the severity of SCH. Cases of SCH were identified from the autopsy database using Snomed codes. Clinical and echocardiograph data were collected for correlation with the pathologic data. A total of 20 adult patients (12 males and 8 females) were identified. Hemoglobin electrophoresis results were available for 16 patients, with hemoglobin S fraction percentages ranging from 23% to 97.8%. Eleven patients had SCD, 5 patients had sickle cell trait (SCT), and the remaining 4 patients without hemoglobin electrophoresis were included in the SCT group. The mean age of the SCT group was higher than that of the SCD group (P = 0.03). Histologically, all 20 patients demonstrated changes in pulmonary vasculature considered diagnostic of pulmonary hypertension grade I to grade IV, associated with plexiform lesions in 60% of patients. Medial hypertrophy and intimal hyperplasia/fibrosis, considered potentially reversible lesions, were seen in all patients. A weak association was found between SCD and plexiform lesions. Fibroelastic degeneration of small arteries, arterioles, and venules was identified in almost all (95%) cases. Clinically, tricuspid regurgitation was detected by echocardiogram in 10 of 20 (50%) patients; 6 of these 10 had significant regurgitation to allow estimation of systolic pressure. Sudden death occurred in 8 patients, with males having a significantly higher incidence. Cardiomegaly was present in 95% of patients, however, autosplenectomy and hepatic cirrhosis/hemochromatosis were observed almost exclusively in patients with SCD. Cirrhosis was found to have a strong positive association with SCD. This study demonstrates pulmonary hypertensive changes in all 20 autopsied patients who had SCH but died from various causes. We conclude that a high prevalence of pulmonary hypertension is associated with SCH with consequent high mortality. Therefore, patients with SCH would benefit from a regular periodic assessment for pulmonary hypertension regardless of age, sex, and severity of hemoglobinopathy.

Fine needle aspiration cytology of hepatobiliary cystadenoma with mesenchymal stroma.

BACKGROUND: Hepatobiliary cystadenomas (HBCs) with mesenchymal stroma (MS) are rare cystic neoplasms occurring exclusively in women. Hepatobiliary cystadenoma consists of a mucin-producing cyst lining epithelium underlined by a dense MS cell layer. In the current study, the authors review the fine needle aspiration cytology of HBC with MS and identify characteristic cytologic features that suggest such an uncommon neoplasm on aspirates. METHODS: A search of the histopathology files at the University of Texas Medical Branch at Galveston for the interval of January 1992 through December 2000 yielded four cases of HBC having both cytologic and histologic specimens. The cytologic features of the aspirates were reviewed and correlated with the clinical history, radiologic findings, and the histopathology of the excised specimens. RESULTS: All four patients were middle-aged women (mean age, 48.5 years) who presented with epigastric pain radiating to the back, due to large cystic lesions in the right liver lobe (three patients) or the left liver lobe (one patient). Aspiration cytology revealed chronic inflammatory exudate in all cases, along with occasional aggregates of bland, cuboidal-columnar epithelial cells (in three cases), which rarely arranged in papillary clusters. No significant atypia, evidence of malignancy, or MS cells were identified on the aspirates. HBC with MS was confirmed histologically on the excised specimens in all cases. CONCLUSIONS: By ensuring adequate sampling and correlating with consistent clinical and radiologic findings, a diagnosis of HBC or cystic hepatobiliary neoplasm can be suggested on the basis of aspiration cytology.