Rossana Porcasi

Low vitamin D serum level is related to severe fibrosis and low responsiveness to interferon‐based therapy in genotype 1 chronic hepatitis C

25‐Hydroxyvitamin D (25[OH]D) can potentially interfere with inflammatory response and fibrogenesis. Its role in disease progression in chronic hepatitis C (CHC) and its relation with histological and sustained virological response (SVR) to therapy are unknown. One hundred ninety‐seven patients with biopsy‐proven genotype 1 (G1) CHC and 49 healthy subjects matched by age and sex were consecutively evaluated. One hundred sixty‐seven patients underwent antiviral therapy with pegylated interferon plus ribavirin. The 25(OH)D serum levels were measured by high‐pressure liquid chromatography. Tissue expression of cytochrome (CY) P27A1 and CYP2R1, liver 25‐hydroxylating enzymes, were assessed by immunochemistry in 34 patients with CHC, and in eight controls. The 25(OH)D serum levels were significantly lower in CHC than in controls (25.07 ± 9.92 μg/L versus 43.06 ± 10.19; P < 0.001). Lower levels of 25(OH)D were independently linked to female sex (P = 0.007) and necroinflammation (P = 0.04) by linear regression analysis. CYP27A1, but not CYP2R1, was directly related to 25(OH)D levels (P = 0.01), and inversely to necroinflammation (P = 0.01). Low 25(OH)D (odds ratio [OR], 0.942; 95% confidence interval [CI], 0.893–0.994) and cholesterol (OR, 0.981; 95%CI, 0.969–0.992) levels, older age (OR, 1.043; 95%CI, 1.002–1.085), high ferritin (OR, 1.003; 95%CI, 1.001–1.005), and necroinflammation (OR, 2.235; 95%CI, 1.014–4.929) were independently associated with severe fibrosis (F3–F4) by multivariate logistic analysis. Seventy patients (41%) achieved SVR. By multivariate analysis, hepatic steatosis (OR, 0.971; 95%CI, 0.944–0.999), lower cholesterol (OR, 1.009; 95% CI, 1.000–1.018), and 25(OH)D levels (OR, 1.039; 95%CI, 1.002–1.077) were independently associated with no SVR. Conclusion: G1 CHC patients had low 25(OH)D serum levels, possibly because of reduced CYP27A1 expression. Low vitamin D is linked to severe fibrosis and low SVR on interferon (IFN)‐based therapy. (HEPATOLOGY 2010.)

Overexpression of interleukin-23, but not interleukin-17, as an immunologic signature of subclinical intestinal inflammation in ankylosing spondylitis

OBJECTIVE Subclinical gut inflammation is common in spondylarthritis, but the immunologic abnormalities underlying this process are undefined. Perturbation of the interleukin-23 (IL-23)/Th17 axis has emerged as a fundamental trigger of chronic inflammation. This study was undertaken to investigate the expression and tissue distribution of IL-23/Th17-related molecules in Crohns disease (CD) and in subclinical gut inflammation in ankylosing spondylitis (AS). METHODS Quantitative gene expression analysis of Th1/Th2 and IL-23/Th17 responses was performed in intestinal biopsy samples obtained from 12 patients with CD, 15 patients with AS, and 13 controls. IL-23 tissue distribution and identification of IL-23-producing cells were evaluated by immunohistochemistry. RESULTS We demonstrated a strong and significant up-regulation of IL-23p19 transcripts in the terminal ileum in patients with AS and patients with CD. IL-23 was abundantly produced by infiltrating monocyte-like cells in inflamed mucosa from AS and CD patients. Notably, we also identified Paneth cells as a major source of IL-23 in patients with AS, patients with CD, and normal controls. Unlike CD, in AS patients, IL-23 was not associated with up-regulation of IL-17 and the IL-17-inducing cytokines IL-6 and IL-1beta. Finally, while the Th1-related cytokines interferon-gamma, IL-12p35, and IL-27p28 were overexpressed only in CD patients, IL-4, IL-5, and STAT-6 were also significantly increased in AS patients. CONCLUSION Our findings indicate that overexpression of IL-23, but not IL-17, is a pivotal feature of subclinical gut inflammation in AS. Identification of resident Paneth cells as a pivotal source of IL-23 in physiologic and pathologic conditions strongly suggests that IL-23 is a master regulator of gut mucosal immunity, providing a pathophysiologic significance to the reported association between IL-23 receptor polymorphisms and intestinal inflammation.

Chronic constipation and food intolerance: A model of proctitis causing constipation

Objective Chronic constipation in children can be linked to cows milk intolerance (CMI) but the existence of a food intolerance-dependent proctitis is still debated. The aim of this study was to evaluate the histologic data in patients with food intolerance-related constipation. Material and methods Fifty-two consecutive patients (22 M, median age 4 years) with chronic constipation unresponsive to common treatment were enrolled. All patients were put on a cows milk-free diet for 4 weeks and those uncured on this diet underwent a subsequent 4-week period of oligoantigenic diet. In the patients cured on elimination diet, a subsequent double-blind food challenge was performed to confirm the diagnosis of food intolerance. At entry to the study, routine hemato-chemical and immunologic assays, rectoscopy, and histologic study of the rectal mucosa were performed. In the patients cured on elimination diet, rectal histology was repeated when they were cured. Results Twenty-four patients were found to be suffering from CMI and 6 from multiple food intolerance. These patients had a normal stool frequency on elimination diet, while constipation reappeared on food challenge. The condition of the remaining 22 patients did not improve on elimination diet. The patients with food intolerance showed a significantly higher frequency of erosions of the mucosa, number of intraepithelial lymphocytes and eosinophils, and number of eosinophils in the lamina propria. Study of the rectal mucus gel layer showed that the food-intolerant patients had a significantly lower thickness than the other subjects studied. In the food intolerant patients, histologic abnormalities disappeared on elimination diet, when the patients were well. Conclusions Food intolerance-related constipation is characterized by proctitis with eosinophil infiltrate of the rectal mucosa. A reduced mucus gel layer can be considered a contributory factor in the pathogenesis of the constipation.

Osteopontin Shapes Immunosuppression in the Metastatic Niche

The matricellular protein osteopontin (OPN, Spp-1) is widely associated with cancer aggressiveness when produced by tumor cells, but its impact is uncertain when produced by leukocytes in the context of the tumor stroma. In a broad study using Spp1(-/-) mice along with gene silencing in tumor cells, we obtained evidence of distinct and common activities of OPN when produced by tumor or host cells in a spontaneously metastatic model of breast cancer. Different cellular localization of OPN is associated with its distinct activities, being mainly secreted in tumor cells while intracellular in myeloid cells. OPN produced by tumor cells supported their survival in the blood stream, whereas both tumor- and host-derived OPN, particularly from myeloid cells, rendered the metastatic site more immunosuppressive. Myeloid-derived suppressor cells (MDSC) expanded with tumor progression at both primary and lung metastatic sites. Of the expanded monocytic and granulocytic cell populations of MDSCs, the monocytic subset was the predominant source of OPN. In Spp1(-/-) mice, the inhibition of lung metastases correlated with the expansion of granulocyte-oriented MDSCs. Notably, monocytic MDSCs in Spp1(-/-) mice were less suppressive than their wild-type counterparts due to lower expression of arginase-1, IL6, and phospho-Stat3. Moreover, fewer regulatory T cells accumulated at the metastatic site in Spp1(-/-) mice. Our data find correlation with lung metastases of human mammary carcinomas that are associated with myeloid cells expressing OPN. Overall, our results unveiled novel functions for OPN in shaping local immunosuppression in the lung metastatic niche.

CD146+ bone marrow osteoprogenitors increase in the advanced stages of primary myelofibrosis

CD146+ bone marrow stromal cells have been recently recognized as clonogenic osteoprogenitors able to organize a complete hematopoietic microenvironment. This study shows their involvement in bone marrow stromal changes occurring in primary myelofibrosis. CD146+ bone marrow stromal cells have been recently recognized as clonogenic osteoprogenitors able to organize a complete hematopoietic microenvironment. In this study we used immunohistochemical analysis to investigate the contribution of CD146+ bone marrow osteoprogenitors to the stromal remodeling occurring in the different stages of primary myelofibrosis. We found that CD146+ cells sited at the abluminal side of the bone marrow vessels and branching among hematopoietic cells significantly increased in the advanced stages of primary myelofibrosis (p<0.001), paralleling the extent of fibrosis (ρ=0.916, p<0.0001) and the microvascular density (r=0.883, p<0.0001). Coherently with a mural cell function, such cells also displayed smooth-muscle actin expression. Our data providing evidence of CD146+ cell involvement in bone marrow stromal changes occurring in primary myelofibrosis are consistent with the capability of these cells to participate in fiber deposition, angiogenesis, and bone formation. They could also represent rationale for new therapies targeting the bone marrow stroma in primary myelofibrosis.

Oncogene-Driven Intrinsic Inflammation Induces Leukocyte Production of Tumor Necrosis Factor That Critically Contributes to Mammary Carcinogenesis

Oncogene activation promotes an intrinsic inflammatory pathway that is crucial for cancer development. Here, we have investigated the actual effect of the inflammatory cytokine tumor necrosis factor (TNF) on the natural history of spontaneous mammary cancer in the HER2/neuT (NeuT) transgenic mouse model. Bone marrow transplantation from TNF knockout mice into NeuT recipients significantly impaired tumor growth, indicating that the source of TNF fostering tumor development was of bone marrow origin. We show that the absence of leukocyte-derived TNF disarranged the tumor vasculature, which lacked pericyte coverage and structural integrity, leading to diffuse vascular hemorrhage and stromal necrosis. In addition, tumor-associated Tie2-expressing monocytes were reduced and cytokine expression skewed from Th2 to Th1 type. Treatment of NeuT mice with anti-TNF antibody partially phenocopied the antitumor effect of TNF-deficient bone marrow cell transplantation, providing a strong preclinical background and rationale for the introduction of TNF antagonists in the treatment of human breast cancer, including basal-like samples for which consolidated targeted therapies do not exist.

Associations between Notch-2, Akt-1 and HER2/neu expression in invasive human breast cancer: a tissue microarray immunophenotypic analysis on 98 patients.

Objective: We aimed to investigate the existence of associations between well-established and newly recognized biological and phenotypic features of breast cancer involved in tumor progression and prognosis. Methods: Ninety-eight cases of invasive breast cancer were assessed for the immunohistochemical expression of estrogen and progesterone receptors, Ki-67, HER2, Akt-1, and Notch-2, using the tissue microarray technique. Data regarding tumor histotype, histological grade, tumor size and lymph node status were collected for each patient and included in the analysis. Results: Several significant associations between histological and/or immunophenotypic features came from the analysis of our data. Positive associations were observed between estrogen and progesterone receptors, tumor grade and proliferation index, tumor grade and HER2, Akt-1 and estrogen receptors, and Notch-2 and HER2. Inverse associations were noted between hormone receptors and tumor grade, hormone receptors and HER2, Akt-1 and tumor grade, and Akt-1 and nodal invasion. Conclusions: Our results, showing the existence of a number of estrogen receptor-positive tumors with Akt-1 expression, better degree of differentiation, and no lymph node involvement, along with the presence of HER2-positive tumors with strong Notch-2 expression, support the role of Notch and Akt in breast cancer progression and suggest that they may also represent new appealing therapeutic targets.

P-selectin glycoprotein ligand-1 as a potential target for humoral immunotherapy of multiple myeloma.

Monoclonal antibodies (mAbs), successfully adopted in the treatment of several haematological malignancies, have proved almost ineffective in multiple myeloma (MM), because of the lack of an appropriate antigen for targeting and killing MM cells. Here, we demonstrate that PSGL1, the major ligand of P-Selectin, a marker of plasmacytic differentiation expressed at high levels on normal and neoplastic plasma cells, may represent a novel target for mAb-mediated MM immunotherapy. The primary effectors of mAb-induced cell-death, complement-mediated lysis (CDC) and antibody-dependent cell-mediated cytotoxicity (ADCC), were investigated using U266B1 and LP1 cell-lines as models. Along with immunological mechanisms, the induction of apoptosis by PSGL1 cross-linking was assessed. The anti-PSGL1 murine mAb KPL1 induced death of MM cells in a dose- and time-dependent fashion and mediated a significant amount of ADCC. KPL1 alone mediated C1q deposition on target cells but proved unable to induce CDC due to inhibition of the lytic activity of complement by membrane complement regulators (mCRP) expressed on the cell surface. Consistently, CDC was induced by KPL1 upon mCRP blockage. Our results suggest a role for PSGL1 in MM humoral immunotherapy and support further in vivo studies assessing the effects of anti-PSGL1 mAbs on MM growth and interaction with the bone marrow microenvironment.

Different immunophenotypical apoptotic profiles characterise megakaryocytes of essential thrombocythaemia and primary myelofibrosis

Aims: Essential thrombocythaemia (ET) and primary myelofibrosis (PMF) share some clinical and pathological features, but show different biological behaviour and prognosis. The latest contributions to understanding the nature of these disorders have focused on bone marrow microenvironment remodelling and proliferative stress, recognising megakaryocytes (MKCs) as “key-cells”. The aim of this study was to investigate the apoptotic profile of ET and PMF MKCs in order to further characterise the biology of these disorders. Methods: Bone marrow biopsy samples from 30 patients with ET, and 30 patients with PMF, were immunophenotypically studied for the expression of pro-apoptotic (Fas, Fas-L, Bax, Bad) and anti-apoptotic (Bcl-2, Bcl-XL, hTERT (human telomerase reverse transcriptase)) molecules and the “executioner” molecule caspase-3. The fraction of MKCs undergoing apoptosis was assessed by deoxynucleotidyl transferase-mediated dUTP nick-end labelling. Results: Only the mitochondrial pathway seemed to be involved in MKC apoptosis. The anti-apoptotic molecule Bcl-XL was predominantly found in ET MKCs (50.5% of ET MKCs versus 35% of PMF MKCs; p = 0.036), while pro-apoptotic molecules Bax and Bad showed a prevalent expression in PMF MKCs (30.5% of ET MKCs versus 55% of PMF MKCs; 41% of ET MKCs versus 52% of PMF MKCs; p = 0.001 and p = 0.068, respectively). A significant fraction of PMF MKCs were committed to apoptosis according to caspase-3 expression and TUNEL, while only few ET cells were committed to apoptosis. hTERT was significantly more expressed in PMF (32% of ET MKCs versus 46% of PMF MKCs; p = 0.022), in agreement with the proliferative nature of this disease. Conclusions: It was found that ET and PMF MKCs, which barely differ in terms of morphology and aggregation, are characterised by markedly different apoptotic profiles. The rather high apoptotic fraction of PMF was able to support the fibrotic nature of this process, while the anti-apoptotic profile of ET cells fits well with their “steady” maturative state.

Frequent Alteration of the Yin Yang 1/Raf-1 Kinase Inhibitory Protein Ratio in Hepatocellular Carcinoma

The transcription factor Yin Yang 1 (YY1) can favor several aspects of tumorigenesis. In turn, Raf-1 Kinase Inhibitor Protein (RKIP) inhibits the oncogenic activities of MAPK and NF-κB pathways and promotes drug-induced apoptosis. Mutual influences between YY1 and RKIP may exist, and there are already separate evidences that relevant increases in YY1 and reductions in RKIP occur in hepatocellular carcinoma (HCC). However, the levels of the two factors have never been concomitantly examined in HCC. We evaluated by RT-PCR the mRNA levels of YY1, YY1AP, RKIP, and survivin in 35 clinical HCCs (91% HCV-related), in their adjacent cirrhotic tissues and in 6 healthy livers. Immunohistochemical analyses were also performed. The ratio of YY1 to RKIP mRNA was constantly profoundly inverted in the tumors compared with the adjacent nontumoral tissues. A similar result occurred frequently at protein level. Hyperactivation of YY1 in tumors was corroborated by its nuclear localization and the finding that in the tumors there were also increases in YY1AP, a YY1 coactivator not expressed in normal liver, and in survivin, as a possible target of YY1. The frequent alteration in the YY1-RKIP balance might represent a marker of malignant progression and be exploited for therapeutic interventions in HCC.