The use of zoledronic acid in men receiving androgen deprivation therapy for prostate cancer with severe osteopenia or osteoporosis.

Objectives: To study the effect of zoledronic acid on patients with pre-existing osteoporosis on androgen deprivation therapy (ADT), who are at highest risk for fracture. Zoledronic acid is a potent bisphosphonate that can prevent osteoporosis in patients with nonmetastatic (M0), prostate cancer (CaP) who are initiating ADT. The effect of zoledronic acid on patients with pre-existing osteoporosis on ADT, who are highest risk for fracture, has not been adequately studied.

Deoxycholate, an endogenous cytotoxin/genotoxin, induces the autophagic stress-survival pathway: implications for colon carcinogenesis.

We report that deoxycholate (DOC), a hydrophobic bile acid associated with a high-fat diet, activates the autophagic pathway in non-cancer colon epithelial cells (NCM-460), and that this activation contributes to cell survival. The DOC-induced increase in autophagy was documented by an increase in autophagic vacuoles (detected using transmission electron microscopy, increased levels of LC3-I and LC3-II (western blotting), an increase in acidic vesicles (fluorescence spectroscopy of monodansycadaverine and lysotracker red probes), and increased expression of the autophagic protein, beclin-1 (immunohistochemistry/western blotting). The DOC-induced increase in beclin-1 expression was ROS-dependent.

Intravenous zoledronic acid to prevent osteoporosis in a veteran population with multiple risk factors for bone loss on androgen deprivation therapy.

Purpose: Androgen deprivation therapy for prostate cancer is associated with osteoporosis and increased fracture risk. Previous studies of zoledronic acid demonstrated bone loss prevention in patients initiating androgen deprivation therapy. There are limited data on patients on prolonged androgen deprivation therapy or in Veterans Affairs patients with multiple risk factors for osteoporosis.

Design and activity of a murine and humanized anti-CEACAM6 single-chain variable fragment in the treatment of pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDA) is a lethal disease, with surgery being the only curative modality for localized disease, and gemcitabine with or without erlotinib remains the standard of therapy for unresectable or metastatic disease. CEACAM6 is overexpressed in human PDA independent of stage or grade and causes anoikis resistance when dysregulated. Because murine monoclonal antibody 13-1 possesses target-specific cytotoxicity in human PDA cell lines, we designed a humanized anti-CEACAM6 single-chain variable fragment (scFv) based on monoclonal antibody 13-1.

Expression of bile acid transporting proteins in Barrett's esophagus and esophageal adenocarcinoma.

Objectives: Barrett's esophagus (BE) is a metaplastic lesion characterized by replacement of the normal squamous epithelium by columnar intestinal epithelium containing goblet cells. It is speculated that this process is an adaptation to protect cells from components of refluxate, such as gastric acid and bile acids. In contrast to the normal squamous epithelium, enterocytes of the distal ileum are adapted to transport bile acids from the intestinal lumen.

Gene Expression and Serum Cytokine Profiling of Low Stage CLL Identify WNT/PCP, Flt-3L/Flt-3 and CXCL9/CXCR3 as Regulators of Cell Proliferation, Survival and Migration.

Gene expression profiling (GEP) of 8 stage 0/I untreated Chronic Lymphocytic Leukemia (CLL) patients showed over-expression of Frizzled 3 (FZD3)/ROR-1 receptor tyrosine kinase (RTK), FLT-3 RTK and CXCR3 G-protein coupled receptor (GPCR). RT-PCR of 24 genes in 21 patients of the WNT pathway corroborated the GEP. Transforming growth factorβ, fibromodulin, TGFβRIII and SMAD2 are also over-expressed by GEP.

Field defects in progression to gastrointestinal tract cancers.

A field of defective tissue may represent a pre-malignant stage in progression to many cancers. However, field defects are often overlooked in studies of cancer progression through assuming tissue at some distance from the cancer is normal. We indicate, however, the generality of field defects in gastrointestinal cancers, including cancers of the oropharynx, esophagus, stomach, bile duct, pancreas, small intestine and colon/rectum.

A novel dietary-related model of esophagitis and Barrett's esophagus, a premalignant lesion.

Barrett's esophagus (BE) is a premalignant lesion in which columnar epithelium (containing goblet cells) replaces esophageal squamous cells. Previous evidence suggested that hydrophobic bile acids and zinc deficiency each play a role in BE development. We fed wild-type C57BL/6 mice a zinc-deficient diet containing the hydrophobic bile acid, deoxycholic acid for various times up to 152 days.

Activation of the interleukin-6/STAT3 antiapoptotic pathway in esophageal cells by bile acids and low pH: relevance to barrett's esophagus.

Objectives: The molecular factors contributing to the development of Barrett's esophagus (BE) are unclear. Our previous studies showed that BE tissues secrete interleukin-6 (IL-6) and express proteins associated with IL-6 signaling, including IL-6 receptor, activated signal transducer and activators of transcription 3 (STAT3), and antiapoptotic proteins Bcl-x(L) and Mcl-1. Here, we test the hypothesis that bile acids and gastric acids, two components of refluxate associated with gastresophageal reflux disease, activate the IL-6/STAT3 pathway.

Five-year colon surveillance after screening colonoscopy.

Background & Aims: Outcomes of colon surveillance after colorectal cancer screening with colonoscopy are uncertain. We conducted a prospective study to measure incidence of advanced neoplasia in patients within 5.5 years of screening colonoscopy.

Deoxycholate-induced colitis is markedly attenuated in Nos2 knockout mice in association with modulation of gene expression profiles.

Nos2 knockout mice were compared to wild-type mice for susceptibility to colitis in response to a diet supplemented with deoxycholate, a bile acid increased in the colon of individuals on a high-fat diet. Wild-type mice fed a fat-related diet, supplemented with 0.2% DOC, develop colonic inflammation associated with increases in nitrosative stress, proliferation, oxidative DNA/RNA damage, and angiogenesis, as well as altered expression of numerous genes.

Bile acids in combination with low pH induce oxidative stress and oxidative DNA damage: relevance to the pathogenesis of Barrett's oesophagus.

Background: Barrett's oesophagus is a premalignant condition associated with an increased risk for the development of oesophageal adenocarcinoma (ADCA). Previous studies indicated that oxidative damage contributes to the development of ADCA.

Objective: To test the hypothesis that bile acids and gastric acid, two components of refluxate, can induce oxidative stress and oxidative DNA damage.

Abnormal expression of biomarkers in incompletely ablated Barrett's esophagus.

Objective: The aim of this study was to evaluate expression of cancer risk-associated biomarkers in columnar epithelium at squamocolumnar junctions produced by an ablation procedure and proton pump inhibitors in incompletely ablated Barrett's esophagus (BE) patients that were nondysplastic prior to ablation.

Summary Background Data: Ablation of BE to squamous epithelium is achievable by combining a re-injury method with acid suppression. We previously reported that, when there is complete ablation, the neo-squamous epithelium is normal histologically and in biomarker expression.

Pathogenesis of diarrhea in the adult: diagnostic challenges and life-threatening conditions.

The mechanisms that regulate ionic balance, fluid absorption and secretion in the gastrointestinal tract are complex. Disturbance of this homeostatic state by bile acids, bacterial enterotoxins and neoplasm-derived secretagogues, for example, can lead to diarrhea. Determining the causes of chronic diarrhea in individual patients may, therefore, represent a diagnostic challenge.

Reduced Pms2 expression in non-neoplastic flat mucosa from patients with colon cancer correlates with reduced apoptosis competence.

Pms2 protein is a component of the DNA mismatch repair complex responsible both for post-replication correction of DNA nucleotide mispairs and for early steps in apoptosis. Germline mutations in DNA mismatch repair genes give rise to hereditary non-polyposis colon cancer, which accounts for about 4% of colon cancers. However, little is known about the expression of mismatch repair proteins in relation to sporadic colon cancer, which accounts for the great majority of colon cancers.

Unique dietary-related mouse model of colitis.

Background: A high-fat diet is a risk factor for the development of inflammatory bowel disease (IBD) in humans. Deoxycholate (DOC) is increased in the colonic contents in response to a high-fat diet. Thus, an elevated level of DOC in the colonic lumen may play a role in the natural course of development of IBD.

Identification of S-nitrosylated proteins after chronic exposure of colon epithelial cells to deoxycholate.

Apoptosis resistance, a condition favoring genomic instability, is associated with higher risk of colorectal cancer. Deoxycholate (DOC) is a hydrophobic bile salt found in high concentrations in colon cancer patients, and induces apoptosis in cultured colonic cells and ex vivo in colonic biopsies. We showed previously that the chronic exposure of colon cancer cells to increasing concentrations of DOC leads to apoptosis resistance, and the suggested mechanism involves oxidative/nitrosative stress.

Clinical predictors of Barrett's esophagus length.

Background: Assessment of clinical factors associated with Barrett's esophagus (BE) length remained within the realm of anecdotal reports or one center's experience. The aim of this multicenter study was to determine which clinical factors are highly correlated with the length of BE.

Methods: Patients diagnosed with BE were recruited into the study from 5 academic centers in the United States.

Crypt-restricted loss and decreased protein expression of cytochrome C oxidase subunit I as potential hypothesis-driven biomarkers of colon cancer risk.

There is an increasing demand for the development of intermediate biomarkers to assess colon cancer risk. We previously determined that a live cell bioassay, which assesses apoptosis resistance in the nonneoplastic colonic mucosa, detects approximately 50% of patients with colon cancer. A hypothesis-driven biomarker that reflects apoptosis resistance in routine formalin-fixed, paraffin-embedded tissue would be easier to use.

Assessment of apoptosis by immunohistochemical markers compared to cellular morphology in ex vivo-stressed colonic mucosa.

Apoptosis competence is central to the prevention of cancer. Frequency of apoptotic cells, after a sample of colonic tissue is stressed, can be used to gauge apoptosis competence and, thus, possible susceptibility to colon cancer. The gold standard for assessment of apoptosis is morphological evaluation, but this requires an experienced microscopist.

Apoptosis resistance in Barrett's esophagus: ex vivo bioassay of live stressed tissues.

Background And Aims: Barrett's esophagus (BE) is a premalignant lesion of the distal esophagus in which squamous epithelial cells are replaced by metaplastic intestinal-like columnar epithelium that contains goblet cells. The factors that contribute to the progression from normal squamous mucosa to BE, Barrett's dysplasia, and adenocarcinoma are not well understood at the molecular level. Since reflux of bile acids is associated with BE development, we speculate that cells with an apoptosis-resistant phenotype are selected after long-term repeated exposure to pulses of bile acids.

American Society of Clinical Oncology Technology Assessment: chemotherapy sensitivity and resistance assays.

Purpose: To develop a technology assessment of chemotherapy sensitivity and resistance assays in order to define the role of these tests in routine oncology practice.

Methods: The American Society of Clinical Oncology (ASCO) established a Working Group to develop the technology assessment. The Working Group collaborated with the Blue Cross and Blue Shield Association (BCBSA) Technology Evaluation Center.

Increased expression and secretion of interleukin-6 in patients with Barrett's esophagus.

Purpose: Barrett's esophagus (BE) is a common premalignant lesion of the distal part of the esophagus that arises as a consequence of chronic duodenogastroesophageal reflux. Interleukin (IL)-6 is a pleiotropic cytokine that regulates immune defense mechanisms and hematopoiesis. In addition, IL-6 may also be involved in malignant transformation and tumor progression.

A proteomic study of resistance to deoxycholate-induced apoptosis.

The development of apoptosis resistance appears to be an important factor in colon carcinogenesis. To gain an understanding of the molecular pathways altered during the development of apoptosis resistance, we selected three cell lines for resistance to induction of apoptosis by deoxycholate, an important etiologic agent in colon cancer. We then evaluated gene expression levels for 825 proteins in these resistant lines, compared with a parallel control line not subject to selection.