High incidence of thyroid cancer among patients with acromegaly.

PURPOSE: Several studies have suggested that patients with acromegaly have an increased risk of thyroid, colorectal, breast and prostate cancers. In this study we determined the prevalence of malignant neoplasms in patients with acromegaly. METHODS: Cancer risk was evaluated in a cohort of 110 patients (M/F 48/62, age 58.63±13.8 years, range 30-86) with acromegaly. Mean age at diagnosis of acromegaly was 46.37±13.11 years. Mean period of time since diagnosis of acromegaly was 12.26+9.6 years. RESULTS: From 110 patients, cancer was diagnosed in 26 (23.6%) patients. Thyroid cancer was the most common cancer and was diagnosed in 13 patients (11.8%); other cancers encountered were gastric cancer (N=2), endometrial cancer (N-2), and breast cancer, colon cancer, prostate cancer (N-2), myelodysplastic syndrome, renal cell carcinoma, lung cancer and pancreatic carcinoma, one case each. Age, gender, age at the time of diagnosis of acromegaly, tumor size of pituitary adenoma and duration of disease were not associated with cancer development. CONCLUSIONS: This study suggests that patients with acromegaly have an increased risk of thyroid cancer and therefore they should undergo regular screening with hormonal and ultrasound evaluation of the thyroid and FNAB when required.

Vitamin D in acutely ill patients.

Objective To investigate 25(OH)D3 levels and their relationship to survival in a cohort of acutely ill patients on admission to an intensive care unit. Methods This study enrolled acutely ill patients at admission to an intensive care unit and a group of sex- and age-matched healthy control subjects. The 25(OH)D3 levels were measured using an enzyme immunoassay. C-reactive protein and procalcitonin levels were also measured using immunoassays. Results A total of 50 acutely ill patients and 50 healthy control subjects were enrolled in the study. The mean ± SEM 25(OH)D3 levels were significantly lower in the acutely ill patients compared with the control group (11.74 ± 0.88 ng/ml versus 24.66 ± 1.60 ng/ml, respectively). The 25(OH)D3 levels were not related to survival. An inverse relationship was observed between 25(OH)D3 levels and C-reactive protein levels. A weak inverse relationship was also observed between 25(OH)D3 levels and procalcitonin levels. Conclusions The 25(OH)D3 levels were decreased in acutely ill patients admitted to an intensive care unit compared with healthy control subjects. 25(OH)D3 levels may be inversely related to C-reactive protein and procalcitonin levels.

Induction of protective cellular immune responses against experimental visceral leishmaniasis mediated by dendritic cells pulsed with the N-terminal domain of Leishmania infantum elongation factor-2 and CpG oligodeoxynucleotides.

Leishmania elongation factor 2 (EF-2) has been previously identified as a TH1-stimulatory protein. In this study, we assayed the protective potential of the N-terminal domain of EF-2 (N-LiEF-2, 1-357 aa) that has been predicted to contain several overlapping MHC class I and II-restricted epitopes injected in the form of dendritic cell (DC)-based vaccine. Ex vivo pulsing of DCs with the recombinant N-LiEF-2 domain along with CpG oligodeoxynucleotides (ODNs) resulted in their functional differentiation. BALB/c vaccinated with CpG-triggered DCs pulsed with N-LiEF-2 were found to be the most immune-reactive in terms of induction of DTH responses, increased T cell proliferation and IL-2 production. Moreover, vaccination induced antigen-specific TH1 type immune response as evidenced by increased IFN-γ and TNFα levels followed by a significant increase of nitrite (NO) and reactive oxygen species (ROS) in splenocyte cultures. Vaccinated mice showed a pronounced decrease in parasite load in spleen and liver when challenged with L. infantum, increased expression of Stat1 and Tbx21 mRNA transcripts versus reduced expression of Foxp3 transcripts and were able to produce significantly elevated levels of IL-2, IFN-γ and TNFα but not IL-10 compared to non-vaccinated mice. Both antigen and parasite-specific CD4+ T and CD8+ T cells contributed to the IFN-γ production indicating that both subtypes contribute to the resistance to infection and correlated with robust nitrite generation, critical in controlling Leishmania infection. Together, these findings demonstrated the immunogenic as well as protective potential of the N-terminal domain of Leishmania EF-2 when given with CpG-triggered DCs representing a basis for the development of rationalized vaccine against leishmaniasis.

GLI2 Is a Regulator of ß-Catenin and Is Associated with Loss of E-Cadherin, Cell Invasiveness, and Long-Term Epidermal Regeneration.

Uncontrolled hedgehog (HH)/glioma-associated oncogene (GLI) and WNT/ß-catenin signaling are important events in the genesis of many cancers including skin cancer and are often implicated in tumor progression, invasion, and metastasis. However, because of the complexity and context dependency of both pathways, little is known about HH and WNT interactions in human carcinogenesis. In the current study, we provide evidence of HH/glioma-associated oncogene family zinc finger 2 (GLI2)-WNT/ß-catenin signaling crosstalk in human keratinocytes. Overexpression of GLI2ΔN in human keratinocytes resulted in cytoplasmic accumulation and nuclear relocalization of ß-catenin in vitro and in 3D organotypic cultures, accompanied by upregulation of WNT genes. Induction of GLI2ΔN enhanced the ß-catenin-dependent transcriptional activation and the subsequent activation of ß-catenin target genes including cyclin-D1. Additionally, GLI2 overexpression was associated with decreased E-cadherin protein levels; increased expression of SNAIL, matrix metalloproteinase 2, and integrin ß1; and increased cell invasion in 3D organotypic cultures. Invasion was reduced by WNT inhibition, thus unveiling the direct role of GLI2/WNT crosstalk in cell invasion. We show that GLI2 overexpression supported long-term epidermal regeneration in 3D organotypic cultures, and resulted in the manifestation of an undifferentiated basal/stem cell-associated phenotype in human keratinocytes. Both these observations are consistent with the role of ß-catenin and SNAIL in epidermal stem cell maintenance. This work suggests that GLI2 is a regulator of ß-catenin and provides insights into its role in tumorigenesis.

Role for WNT16B in human epidermal keratinocyte proliferation and differentiation.

WNT signalling regulates a variety of cell functions including cell fate, polarity, and differentiation via the canonical or beta-catenin stabilisation pathway and/or the planar cell polarity or non-canonical pathway. We have previously demonstrated that two isoforms (A and B) from the WNT16 locus have differential expression in various adult human tissues. In this study we show that WNT16B but not WNT16A isoform was upregulated in basal cell carcinomas compared with normal skin. We further investigated the cellular and molecular functions of WNT16B in primary human epidermal keratinocytes and a keratinocyte cell line. Cellular expression of WNT16B neither stabilised beta-catenin nor activated the lymphoid enhancer factor or T-cell factor transcriptional reporter in primary keratinocytes. WNT16B activated the Jun-N-terminal kinase cascade suggesting the activation of a non-canonical WNT signalling pathway. Constitutive expression of WNT16B significantly enhanced the rate of cell proliferation and prolonged clonogenicity in primary keratinocytes. Silencing WNT16B by RNA interference reduced keratinocyte proliferation. Furthermore, overexpression of WNT16B induced a hyperproliferation phenotype in an organotypical culture system. This work presents the first evidence that WNT16B activates human keratinocyte proliferation possibly via a beta-catenin-independent non-canonical WNT transduction pathway.