Cycling and early pregnant endometrium as a site of regulated expression of the vitamin D system.

In addition to its calciotropic function, the secosteroid 1,25-dihydroxyvitamin D(3) (1,25(OH)(2)D(3)), has potent anti-proliferative/immunomodulatory effects on various tissues. Consistently, the enzyme that catalyzes the synthesis of 1,25(OH)(2)D(3), 1alpha-hydroxylase (1alpha-OHase) and the vitamin D receptor have a widespread tissue distribution. Among site-specific functions, the hormone has been suggested to be involved in uterine physiology. However, molecular analysis of the vitamin D system in normal endometrium throughout the menstrual cycle as well as its regulation in the context of endometrial physiological and pathological events have received very limited attention. Thus, we have studied expression, localization and regulation of 1alpha-OHase in human cycling and early pregnant endometrium. The capacity for 1alpha-hydroxylation and the presence of vitamin D receptor in endometrial cells have also been evaluated. The functional significance of these findings has been tested by evaluating gene expression of the catabolic enzyme, vitamin D 24-hydroxylase, and of the adhesion protein, osteopontin. Finally, to verify any potential dysfunction of the vitamin D system in endometriosis, a reproductive disease characterized by immune-mediated anomalies, we have analyzed expression of 1alpha-OHase in both eutopic and ectopic endometrium of affected patients. Results obtained showed that the active form of the 1alpha-OHase gene was expressed in human endometrial stromal cells independent of the cycle phase but with a significant increase in early pregnant decidua. A similar profile was observed for the protein, which was abundantly expressed in the cytoplasm of both endometrial stroma and epithelial glands. Both cycling and early pregnant endometrial cells also expressed the vitamin D receptor. In the same cells, 1alpha-OHase mRNA levels were significantly stimulated by the pro-inflammatory cytokine interleukin (IL)-1beta (50 and 500 pg/ml) while addition of the active form of the hormone could modulate both CYP24 and osteopontin gene expression. The 1alpha-OHase gene was also expressed in ectopic endometrium and its levels were increased in proliferative phase cultures derived from patients with endometriosis. Human cycling endometrium may be included among the extrarenal sites able to synthesize vitamin D. The IL-1beta-mediated induction of 1alpha-OHase gene and the hormonal modulation of osteopontin support a role for the hormone in the immunological mechanisms underlying uterine function. Abnormalities of this system are present in endometriosis.

Plasmablastic lymphoma of the stomach. A case report.

We report the case of a 53 year-old woman with a gastric tumor showing morphological, phenotypical and molecular features of a plasmablastic lymphoma, a recently recognized subtype of diffuse large B-cell lymphoma. The tumor was composed of plasmablast-like cells, lacked CD45 and B-cell associated antigens, expressed the plasma cell-associated antigen CD38, and showed clonally rearranged IgH genes in the absence of bcl-2 and bcl-6 genes rearrangement.

Polysialylated N-CAM, chromogranin A and B, and secretogranin II in neuroendocrine tumours of the lung.

Highly alpha 2-8-sialylated N-CAM (neural cell adhesion molecule) impairs N-CAM-mediated cell adhesion. We investigated polysiaN-CAM immunoreactivity in a range of neuroendocrine lung tumours: 15 typical carcinoids, 21 atypical carcinoids, 2 large cell neuroendocrine carcinomas and 12 small cell lung carcinomas were selected on a morphological basis and by their immunoreactivity for chromogranin A and B and secretogranin II. A progressive loss of chromogranin expression, particularly of chromogranin B, was paralleled by the up-regulation of polysiaN-CAM in histologically more aggressive tumours (P = 0.001). These data support the hypothesis that loss of cell-cell adhesion properties might be a relevant factor in the origin of the aggressivity of lung neuroendocrine tumours.

Analysis of estrogen and progesterone receptors on preoperative fine-needle aspirates.

For 56 cases of carcinoma of the breast, results of the immunocytochemical assay for estrogen and progesterone receptors performed on preoperative fine-needle aspirates were compared with those obtained on scraping material from the same tumors. The value and usefulness of this last analysis was demonstrated in a previous study. The level of agreement between the two cytological techniques was assessed by the k statistic. A high level of agreement was found, with k values of 0.909 and 0.889 for estrogen and progesterone receptors, respectively. The results reported here revealed the reliability of steroid receptor determination on fine-needle aspiration biopsies, provided that sufficient cellularity was available. This technique can replace the open biopsy procedure, in as much as it represents a rapid, almost painless, and easily repeated method for the assessment of the receptor status, and is useful for treatment decisions at any time during the course of the disease.

Immunodetection of secretogranin II in animal and human tissues by new monoclonal antibodies.

Secretogranin II (chromogranin C) is an acidic tyrosine-sulfated secretory protein, known to be a marker of neuroendocrine secretory products and of specific neuroendocrine tumours. In order to obtain anti-secretogranin II monoclonal antibodies for cell biology studies and, in particular, for clinical applications, we immunized mice with a secretogranin II-enriched fraction prepared from homogenates of bovine anterior pituitaries. Hybridoma supernatants obtained from the splenocytes of a hyperimmune mouse, screened with an enzyme-linked immunosorbent assay, were analyzed by both immunocytochemistry and two-dimensional immunoblotting. By using this experimental approach, we were able to identify two monoclonal antibodies (8G1 and 5A7) which recognize bovine secretogranin II. Both immunocytochemistry and immunoblotting revealed that one of them, the 5A7 antibody, cross-reacts with the human antigen. The distribution patterns of the immunoreactivity, obtained by immunocytochemistry with the 5A7 antibody in animal and human tissues, partially overlap those, obtained by using a polyclonal antiserum elicited against bovine secretogranin II, previously described. Moreover, the 5A7, but not the polyclonal antibody, reacts with some duodeno-jejunal cells. In conclusion, both the 5A7 and 8G1 antibodies can be useful for cell biology studies. The 5A7 antibody can be used for the detection of secretogranin II in human tissues and should be of help in clinical and pathological practices.