Long-term treatment with thalidomide for severe recurrent hemorrhage from intestinal angiodysplasia in Glanzmann Thrombasthenia.

Gastrointestinal angiodysplasia (GIA) is the most common cause of occult gastrointestinal bleeding (GIB) requiring often hospitalization and transfusions, especially in patients with hemorrhagic disorders. Thalidomide, impairing neo-angiogenesis, has been successfully used in the management of bleeding in patients with GIA and in particular in patients with inherited bleeding disorders. Only one case of short-term treatment with thalidomide in a patient with Glanzmann thrombasthenia (GT) and recurrent GIB due to GIA has been reported so far.We report the case of a woman with GT developing high frequency recurrent GIB due to GIA requiring repeated blood and platelet transfusions, who was treated with thalidomide obtaining a striking and stable reduction of GIB and of the requirement of platelet and blood transfusions for over 5 years. Moreover, we raise the suspicion that the association between GT and GIA may not be fortuitous.

Sunitinib inhibits tumor vascularity and growth but does not affect Akt and ERK phosphorylation in xenograft tumors.

Sunitinib is a multikinase inhibitor approved for use in some human solid malignancies, including renal clear cell and gastrointestinal stromal cancer, and under investigation for many other neoplasias. In many preclinical cancer models sunitinib has shown anti-angiogenic and antitumor effects, acting mainly by inhibiting the activity of pro-angiogenic growth factor receptors. However, a percentage of tumors develop resistance to this treatment. The aim of this study was to identify novel potential molecular targets for the non- responsive tumors. The effects of sunitinib were investigated in xenograft tumors obtained by injecting HEK293 cells into NOD-SCID mice, focusing on the activity of growth-regulating pathways involved in tumorigenesis. During 11 days of oral administration of sunitinib (40 mg/kg/day), the growth of tumors was monitored by measuring the mass volume by a caliper. At the end of the treatment, tumor specimens were histologically examined for microvessel density (MVD) and presence of necrosis, and the phosphorylation of ERK and Akt was analyzed in protein extracts by Western blotting. Moreover, the mRNA levels of VEGF and its receptor genes were measured by quantitative RT-PCR. Treatment with sunitinib elicited a clear reduction of the tumor growth, associated with a reduction of MVD, correlated with an increased number of necrotic cells. In contrast, the levels of phosphorylated Akt and ERK proteins were similar in treated and non-treated animals. The VEGF and VEGFR-1 and 2 transcripts were not affected by sunitinib treatment. In conclusion, these findings confirm the anti-angiogenic action as the major effect of sunitinib against tumor growth. In contrast, other important growth regulatory pathways involved in malignant trans-formation, such as the ERK-MAPK and Akt/mTOR pathways are not affected by such a treatment, suggesting the use of specific inhibitors of these pathways as valid candidates for combinatorial therapies in sunitinib-resistant malignancies.

Recent advances in adrenal autoimmunity.

Autoimmune Addison's disease (AAD) results from the immune-mediated destruction of adrenocortical cells. AAD is a major component of the autoimmune polyendocrine syndromes type 1 (APS 1) and type 2. The adrenal autoimmune process is made evident by the apperance of circulating autoantibodies against the steroidogenic enzyme 21-hydroxylase. Detection of 21-hydroxylase in patients with endocrine autoimmune diseases enables the identification of subjects with preclinical AAD. An impaired response to a corticotrophin stimulation test marks the irreversible stage of preclinical AAD and predicts progression towards clinical AAD in over 80% of cases. APS 1 is caused by mutations of the autoimmune regulator (AIRE) gene, which encodes an activator of transcription, Aire, that induces the expression of autoantigens in thymic medullary epithelial cells and promotes immunological tolerance. Isolated and APS 2-related AAD is an autoimmune disease with evidence for complex genetic susceptibility caused by T-cell-mediated destruction of adrenocortical cells, with a major contribution of HLA genes. The target cells in the adrenal cortex participate in the immune reaction by releasing chemokines, such as CXCL-10, that attract Th1 cells.

Radioiodine uptake in non-lactating mammary glands: evidence for a causative role of hyperprolactinemia.

CONTEXT: Radioiodine uptake is rarely observed in normal non-lactating breast tissue. Investigation of the in vivo regulation of iodide uptake in breast tissue may be useful for the induction of radioiodine uptake in breast cancer tissue for diagnostic and therapeutic purposes. CASE REPORTS: We report the cases of two post-menopausal women who underwent radioiodine therapy for papillary thyroid carcinoma and in whom breast uptake of radioiodine on post-therapy whole body scan (WBS) was observed. METHODS AND RESULTS: In both patients, elevated serum prolactin levels (123 ng/mL in patient 1 and 48 ng/mL in patient 2) were documented at the time when radioiodine uptake in the breast was observed. The hyperprolactinemia was due to prolonged treatment with the anti-dopaminergic neuroleptic risperidone in Case 1, and chronic renal failure in Case 2. When prolactin levels were normalized (by withdrawal of risperidone in Case 1 and with cabergoline in Case 2), breast tissue uptake was no longer evident on WBS. CONCLUSION: These cases provide the first documented correlation between serum levels of endogenous prolactin and radioiodine uptake by involuted breast tissue in humans.

Improved in planta expression of the human islet autoantigen glutamic acid decarboxylase (GAD65).

The smaller isoform of the enzyme glutamic acid decarboxylase (GAD65) is a major islet autoantigen in autoimmune type 1 diabetes mellitus (T1DM). Transgenic plants expressing human GAD65 (hGAD65) are a potential means of direct oral administration of the islet autoantigen in order to induce tolerance and prevent clinical onset of disease. We have previously reported the successful generation of transgenic tobacco and carrot that express immunoreactive, full-length hGAD65. In the present study, we tested the hypothesis that the expression levels of recombinant hGAD65 in transgenic plants can be increased by targeting the enzyme to the plant cell cytosol and by mediating expression through the potato virus X (PVX) vector. By substituting the NH2-terminal region of hGAD65 with a homologous region of rat GAD67, a chimeric GAD67(1-87)/GAD65(88-585) molecule was expressed in transgenic tobacco plants. Immunolocalization analysis showed that immunoreactive GAD67/65 was found in the plant cell cytosol. By using a radio-immuno assay with human serum from a GAD65 autoantibody-positive T1DM patient, the highest expression level of the recombinant GAD67/65 protein was estimated to be 0.19% of the total soluble protein, compared to only 0.04% of wild-type hGAD65. Transient expression of wild-type, full-length hGAD65 in N. benthamiana mediated by PVX infection was associated with expression levels of immunoreactive protein as high as 2.2% of total soluble protein. This substantial improvement of the expression of hGAD65 in plants paves the way for immunoprevention studies of oral administration of GAD65-containing transgenic plant material in animal models of spontaneous autoimmune diabetes.

CTLA-4-Ig regulates tryptophan catabolism in vivo.

Cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) plays a critical role in peripheral tolerance. However, regulatory pathways initiated by the interactions of CTLA-4 with B7 counterligands expressed on antigen-presenting cells are not completely understood. We show here that long-term survival of pancreatic islet allografts induced by the soluble fusion protein CTLA-4-immunoglobulin (CTLA-4-Ig) is contingent upon effective tryptophan catabolism in the host. In vitro, we show that CTLA-4-Ig regulates cytokine-dependent tryptophan catabolism in B7-expressing dendritic cells. These data suggest that modulation of tryptophan catabolism is a means by which CTLA-4 functions in vivo and that CTLA-4 acts as a ligand for B7 receptor molecules that transduce intracellular signals.

Autoantibody profile and epitope mapping in latent autoimmune diabetes in adults.

The presence of islet cell autoantibodies in adult diabetic subjects who do not require insulin treatment for at least six months after the initial clinical diagnosis identifies the so-called latent autoimmune diabetes in the adult (LADA). Glutamic acid decarboxylase autoantibodies (GAD65Ab) are the best immune marker to identify LADA patients, while other islet autoantibodies, such as IA-2 autoantibodies, have a very low diagnostic sensitivity. Islet cell antibodies, as detected by indirect immunofluorescence, may improve the diagnostic specificity of the immune analysis when detected in GAD65Ab-positive patients. Although the majority of LADA patients progresses towards insulin dependency within a few years after the diagnosis, this form of diabetes is heterogeneous. The presence of high titers of GAD65Ab and/or GAD65Ab directed towards COOH-terminal epitopes of the autoantigen (GAD65-CAb) identifies a subgroup of LADA patients with clinical characteristics similar to those of typical type 1 diabetes and at very high risk of progression toward insulin dependency. On the other hand, low titers of GAD65Ab, or the exclusive presence of GAD65Ab directed to middle epitopes of the autoantigen, characterizes LADA patients with clinical characteristics almost indistinguishable from those of GAD65Ab-negative type 2 diabetic patients. LADA subjects, especially in the presence of high titers of GAD65Ab and/or GAD65-CAb, have an increased risk for other organ-specific autoimmune diseases such as thyroid autoimmune diseases or autoimmune Addison's. LADA should be considered a major component of the autoimmune polyendocrine syndromes, and screening for other autoimmune diseases should be performed in all LADA patients.