CCL25/CCR9 interactions are not essential for colitis development but are required for innate immune cell protection from chronic experimental murine colitis.

BACKGROUND: The chemokine CCL25, and its receptor CCR9, constitute a unique chemokine/receptor pair, which regulates trafficking of T lymphocytes to the small intestine under physiological conditions and is an attractive target for small bowel Crohn's disease drug development. We have previously shown that CCL25/CCR9 interactions regulate the recovery from acute dextran sulfate sodium-induced colonic inflammation. In this study, we explored whether these interactions also regulate chronic colitis development in 2 independent murine models of experimental colitis. METHODS: Histological flow cytometry and qPCR analyses were performed to evaluate the role of CL25 and CCR9 in chronic colonic inflammation induced by serial exposures to dextran sulfate sodium salts or by adoptive transfer of CD45RB(hi) CD4(+) T cell into lymphopenic mice devoid of CCL25/CCR9 interactions. RESULTS: Chronic dextran sulfate sodium exposure results in exacerbated colitis in mice deficient for either CCR9 or CCL25 when compared with wild-type control mice. Although CCR9-deficient T cells traffic to the colon and induce severe colitis similar to wild-type T cells in the CD45RB transfer model, naive wild-type T cells induce more severe disease in recipient animals devoid of CCL25 expression. CONCLUSIONS: CCL25/CCR9 interactions are required for modulating protection against large intestinal inflammation in 2 models of chronic colitis. These data may have implications for the potential effects of disrupting CCL25/CCR9 interactions in humans in the setting of intestinal disorders including inflammatory bowel disease.

Targeted therapies and predictive markers in epithelial malignancies of the gastrointestinal tract.

CONTEXT: In recent years, there has been a tremendous amount of interest in the development of targeted therapies for the treatment of human cancers. Increased understanding of the specific molecular pathways and driver mutations critical to cancer cell growth have allowed the development of these advanced therapeutics. Among these, inhibitors of the epidermal growth factor receptor and HER2/neu pathways now play a major role in the management of gastrointestinal cancers in addition to other solid malignancies. In colorectal and gastric cancers, the use of epidermal growth factor receptor inhibitors and HER2/neu inhibitors has increased the available treatment options for patients with advanced disease. OBJECTIVE: To focus on the current targeted therapies and predictors of response in malignancies of the gastrointestinal tract. DATA SOURCES: Medical literature searchable on PubMed (US National Library of Medicine) as well as older studies revealed by the literature review were used as the source of data. CONCLUSION: Gene testing of critical elements of the pathways targeted by these agents (such as KRAS mutational analysis in colorectal tumors and HER2/neu testing in gastric cancers) allows the ability to predict which patients will respond to these treatments. As the molecular profiling of tumors and our understanding of cancer genomics and epigenetic alterations continues to grow, it is expected that these personalized targeted therapies will form one of the mainstays of gastrointestinal cancer treatment.

MUC2 is a highly specific marker of goblet cell metaplasia in the distal esophagus and gastroesophageal junction.

Currently, the American College of Gastroenterology requires identification of goblet cells in mucosal biopsies from the esophagus to diagnose Barrett esophagus (BE). Identification of goblet cells in mucosal biopsies is fraught with limitations such as sampling and interpretation error. One previous study by our group suggested that MUC2 expression in esophageal nongoblet columnar cells represents a late biochemical reaction in the conversion of mucinous columnar cells to goblet cells in BE. We conducted this study to evaluate the prevalence, sensitivity, and specificity of MUC2 positivity in nongoblet columnar epithelium for detection of goblet cells in the distal esophagus and gastroesophageal junction (GEJ) region. We also sought to identify associations between MUC2 positivity and clinical and endoscopic risk factors for BE. This analysis utilized mucosal biopsies of the distal esophagus or GEJ from 100 patients who participated in a community clinic-based study of patients with chronic gastroesophageal reflux disease evaluated prospectively in the western part of Washington state. We randomly selected 50 patients who had columnar epithelium with goblet cells, representing the study group and 50 patients without goblet cells, representing the comparison group. Immunohistochemistry for MUC2 was performed on samples in a blinded manner without knowledge of the clinical or endoscopic features of the patients. The presence of staining was noted in both goblet and nongoblet epithelium, both close to and distant from the mucosa with goblet cells, when the latter were present. All study patients showed MUC2 positivity in goblet cells. MUC2 was present in nongoblet columnar epithelium in 78% of study patients with goblet cells, but in only 4% of controls without goblet cells (P<0.0001) (sensitivity, 78%; specificity, 96% for goblet cell metaplasia). MUC2 was significantly more common in nongoblet columnar cells close to, rather than distant from, the mucosa with goblet cells (P<0.00001). Finally, MUC2 was significantly associated with endoscopic evidence of columnar metaplasia in the distal esophagus, and with known risk factors for BE, such as older age, white race, frequent heartburn, and elevated body mass index. We conclude that goblet cells likely develop from a field of MUC2-positive mucinous columnar cells, and as such, MUC2 represents a late event in the development of goblet cells. MUC2 staining in nongoblet columnar cells is a reasonably sensitive and highly specific marker for goblet cells in the distal esophagus and GEJ, and its presence is predictive of endoscopic columnar metaplasia of the esophagus, even in patients without goblet cells.

CCL25/CCR9 interactions regulate large intestinal inflammation in a murine model of acute colitis.

BACKGROUND AIMS: CCL25/CCR9 is a non-promiscuous chemokine/receptor pair and a key regulator of leukocyte migration to the small intestine. We investigated here whether CCL25/CCR9 interactions also play a role in the regulation of inflammatory responses in the large intestine. METHODS: Acute inflammation and recovery in wild-type (WT) and CCR9(-/-) mice was studied in a model of dextran sulfate sodium (DSS)-induced colitis. Distribution studies and phenotypic characterization of dendritic cell subsets and macrophage were performed by flow cytometry. Inflammatory bowel disease (IBD) scores were assessed and expression of inflammatory cytokines was studied at the mRNA and the protein level. RESULTS: CCL25 and CCR9 are both expressed in the large intestine and are upregulated during DSS colitis. CCR9(-/-) mice are more susceptible to DSS colitis than WT littermate controls as shown by higher mortality, increased IBD score and delayed recovery. During recovery, the CCR9(-/-) colonic mucosa is characterized by the accumulation of activated macrophages and elevated levels of Th1/Th17 inflammatory cytokines. Activated plasmacytoid dendritic cells (DCs) accumulate in mesenteric lymph nodes (MLNs) of CCR9(-/-) animals, altering the local ratio of DC subsets. Upon re-stimulation, T cells isolated from these MLNs secrete significantly higher levels of TNFα, IFNγ, IL2, IL-6 and IL-17A while down modulating IL-10 production. CONCLUSIONS: Our results demonstrate that CCL25/CCR9 interactions regulate inflammatory immune responses in the large intestinal mucosa by balancing different subsets of dendritic cells. These findings have important implications for the use of CCR9-inhibitors in therapy of human IBD as they indicate a potential risk for patients with large intestinal inflammation.

Prognostic value of xanthine oxidoreductase expression in patients with non-small cell lung cancer.

BACKGROUND: Xanthine oxidoreductase (XOR) is a rate-limiting enzyme in the purine metabolism pathway. Lack of XOR expression is associated with unfavorable clinical outcomes. The objective of this study was to correlate XOR expression with prognosis in surgically resected non-small cell lung cancer (NSCLC). METHODS: Immunohistochemical staining was performed on deparaffinized specimens from 82 patients with stage I-IV NSCLC using a polyclonal anti-XOR rabbit antibody. Cytoplasmic XOR staining was scored on frequency and intensity scales from 0 to 4 with low expression defined as 0-1 and high expression defined as ≥2-4. XOR immunostaining was correlated with clinical characteristics and outcomes and analyzed using Kaplan-Meier and Cox proportional hazard methods. RESULTS: Positive XOR expression was observed in 53/82 cases (65%). Patients with high XOR frequency had a longer median survival of 3053 days (95% CI: 2190-3916) vs. 592 days (95% CI: 492-692 days) for patients with low XOR frequency, p=0.0089, HR 0.47. Neither XOR intensity nor the overall score of XOR frequency multiplied by XOR intensity demonstrated any significant association with survival. Surgical resection was performed on 61 patients of which 34 (56%) received adjuvant chemotherapy. Patients who received adjuvant chemotherapy with low XOR expression, 15/34 (44%) had a shortened median survival compared with patients who received adjuvant chemotherapy with high XOR expression (543 days vs. 2023 days, respectively, p=0.007 and HR=0.33). CONCLUSION: Low XOR expression was associated with shortened survival and also conferred a worse prognosis for patients with NSCLC who received adjuvant chemotherapy. Further studies of the XOR pathway are warranted to validate and mechanistically explain these outcomes.

Epidermal growth factor receptor gene amplification in atypical adenomatous hyperplasia of the lung.

Atypical adenomatous hyperplasia (AAH) is postulated to be the earliest morphologic precursor lesion in lung carcinogenesis. The epidermal growth factor receptor (EGFR), one of the members of the Erb-2 family of receptors, is commonly expressed in non-small cell lung carcinoma (NSCLC). A subset of the patients with NSCLC has molecular abnormalities in the EGFR gene, including missense mutations and deletions and/or abnormal gene copy numbers, and the relative importance of each of these for patient outcome is an area of great interest. Recent reports show that EGFR mutations are rare or absent in AAH and are rare in bronchioloalveolar carcinoma (BAC). However, the EGFR gene copy number status in AAH is unknown. In this study, we examined the EGFR gene copy number status in lung adenocarcinomas, synchronous AAH, and BAC in surgical pathology resection specimens. EGFR gene copy number was analyzed by chromogenic in situ hybridization (CISH) using formalin fixed paraffin embedded tissue sections and EGFR probes as recommended by the manufacturer. A known positive case of high-grade glioma was used as a positive control. The results indicate that four of eight adenocarcinomas (50%) had more than five EGFR signals per nucleus, suggesting a gain in copy number. Interestingly, in four of nine cases of AAH (44.4%) more than three EGFR signals per nucleus were noted, with scattered cells showing up to 6 signals per nucleus. In addition, in five of 12 cases of BAC (42%), more than three EGFR signals per nucleus were noted. In the remaining cases two to three intranuclear dot-like peroxidase positive signals were present consistent with non-amplification of the gene. Our study reveals an abnormal EGFR gene copy gain in several cases of AAH. In our cohort, the rate of EGFR gene copy abnormalities in AAH appears similar to BAC and lower than in lung adenocarcinomas. These findings suggest that although EGFR gene copy abnormalities may be an early event in lung carcinogenesis, they are associated with tumor progression to invasive cancer and highlight the complexity of tumor morphogenesis.

Cytologic imprints of giant atypical bronchopulmonary carcinoid tumor of the lung with extensive oncocytic component.

Bronchopulmonary carcinoid tumors are found in less than 2 of 100,000 people yearly and comprise approximately 1-2% of all lung neoplasms. They are usually diagnosed in the fifth decade of life and occur more frequently in women. Most are central and endobronchial in location. The symptoms presented are those associated with bronchial obstruction, such as coughing, wheezing, and dyspnea. Over one-third of patients are asymptomatic and have an incidentally detected peripheral pulmonary nodule. Diagnosis is usually made by bronchoscopy with bronchial brushings or biopsy. We present the cytologic imprint findings of a case of a 66-year-old man with an atypical giant bronchopulmonary carcinoid with extensive oncocytic component, who underwent a total right pneumonectomy.

Cytologic features of primary chondroid tumors of bone in crush preparations.

Fine-needle aspiration biopsy can be utilized effectively in the diagnosis of many bone lesions. Often, these lesions are suspected to be foci of metastatic disease based on clinical and/or radiographic findings. On occasion, microscopic examination of the aspirate yields a diagnosis of a primary neoplasm of chondroid origin. We discuss the cytologic features observed in crush preparations of the most frequently seen primary chondroid tumors of bone and how these lesions can be differentiated from each other and from metastatic lesions.

Synchronous metastases to the liver and pancreas from a primary neuroendocrine carcinoma of the breast diagnosed by fine-needle aspiration.

Extrapulmonary neuroendocrine carcinoma is uncommon. Cases of primary neuroendocrine carcinoma of the breast have been reported, though rare. We report the case of a 53-year-old woman who underwent a mastectomy for breast carcinoma and presented three years later with synchronous masses in the head of the pancreas and liver. Fine-needle aspiration of both organs revealed a neuroendocrine carcinoma. The original breast tumor was reviewed and found to express neuroendocrine markers. A diagnosis of a primary neuroendocrine carcinoma of the breast was rendered.