Membranous CD24 drives the epithelial phenotype of pancreatic cancer.

Surface CD24 has previously been described, together with CD44 and ESA, for the characterization of putative cancer stem cells in pancreatic ductal adenocarcinoma (PDAC), the most fatal of all solid tumors. CD24 has a variety of biological functions including the regulation of invasiveness and cell proliferation, depending on the tumor entity and subcellular localization. Genetically engineered mouse models (GEMM) expressing oncogenic KrasG12D recapitulate the human disease and develop PDAC. In this study we investigate the function of CD24 using GEMM of endogenous PDAC and a model of cerulein-induced acute pancreatitis. We found that (i) CD24 expression was upregulated in murine and human PDAC and during acute pancreatitis (ii) CD24 was expressed exclusively in differentiated PDAC, whereas CD24 absence was associated with undifferentiated tumors and (iii) membranous CD24 expression determines tumor subpopulations with an epithelial phenotype in grafted models. In addition, we show that CD24 protein is stabilized in response to WNT activation and that overexpression of CD24 in pancreatic cancer cells upregulated ß-catenin expression augmenting an epithelial, non-metastatic signature. Our results support a positive feedback model according to which (i) WNT activation and subsequent ß-catenin dephosphorylation stabilize CD24 protein expression, and (ii) sustained CD24 expression upregulates ß-catenin expression. Eventually, membranous CD24 augments the epithelial phenotype of pancreatic tumors. Thus we link the WNT/ß-catenin pathway with the regulation of CD24 in the context of PDAC differentiation.

Clinicopathologic characterization of visceral gout of various internal organs--a study of 2 cases from a venom and toxin research center.

BACKGROUND: Gout is a metabolic disorder that results in hyperuricemia and the deposition of positively birefringent monosodium urate crystals in various parts of the body. The purpose of this study was to characterize the incidence and diagnostic features of visceral gout found at necropsy in two patients. CASE PRESENTATION: The authors present an unusual report of untreated gout leading to major structure destructions in visceral organs. Gross post-mortem examination revealed a white powdery substance and display needle-like crystalline symmetry under the macroscopic on the visceral surfaces. Microscopically, the presence of crystalline deposits (urate tophi) were detected in visceral organs, such as; kidney, liver, lung and mesentery. Irrespective of its location, gout was observed, by H&E, as intracellular and extracellular eosinophilic deposits that compressed surrounding tissues. Moreover, numerous necrotizing granulomas of multifarious sizes were observed that were compounded by large aggregations of eosinophilic material (gout), surrounded by epithelioid macrophages, lymphoplasmacytic cells, foreign body multinucleated giant cells, fibrosis, fibroplasia and few edema. On the other hand, our results revealed that granulomatous nodules in the mesentery and kidney contained large numbers of gout foci compared with lung and liver. Furthermore, the immediate cause of death in these cases were not identified, but appeared to result from multiple factors, including the visceral gout due to unsuitable environmental conditions. CONCLUSION: In summary, we have identified a valid histopathologic damage index for use in laboratory studies of visceral gout. This system provides a feasible method of representing visceral damage in gout, and may allow for better understanding of the natural history, pathophysiology and the management of acute attacks of gouty visceral in this disease. Finally, to the best of our knowledge, understanding of the distribution of monosodium urate crystals within the body can aid clinical diagnosis and further understanding of the resulting pathology. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1293547351151638 .

Apoptotic and proliferative activity of mouse gastric mucosa following oral administration of fumonisin B1.

OBJECTIVES: Fumonisins are a group of toxic and carcinogenic mycotoxins, which contaminate the grains and their products. The aim of this study was to examine the apoptotic and proliferative activity of mouse gastric mucosa following administration of fumonisin B1 (FB1). MATERIALS AND METHODS: Twenty-nine female mice divided into treatment (n=15) and control (n=14) groups. The treatment group received FB1 (150 mg/kg diet) for 16 weeks. The gastric atrophy was allocated using grading criteria modeled on the updated Sydney System. Immunohistochemistry studies were performed for evaluation of apoptosis and proliferative activity in gastric mucosa. RESULTS: Mild to moderate gastric atrophy were observed in microscopic findings of the gastric mucosa in treated animals (P<0.05). Number of parietal cells significantly decreased in the treatment group in comparison with the control (P<0.05). Treatment with FB1 for 16 weeks significantly reduced both gastric mucosa height and mitotic index in the gastric glands (P<0.05). TUNEL- and Bax-labeled positive cell numbers significantly increased in the FB1-treated group compared to the control (P<0.05). In addition, proliferative activity of gastric glands in the treated group was significantly lower than the control (P<0.05). CONCLUSION: Oral administration of FB1 caused atrophy in gastric mucosa both via increasing of apoptosis and suppressing the mitotic activity of these cells.

NH4Cl Treatment Prevents Tissue Calcification in Klotho Deficiency.

Klotho, a cofactor in suppressing 1,25(OH)2D3 formation, is a powerful regulator of mineral metabolism. Klotho-hypomorphic mice (kl/kl) exhibit excessive plasma 1,25(OH)2D3, Ca(2+), and phosphate concentrations, severe tissue calcification, volume depletion with hyperaldosteronism, and early death. Calcification is paralleled by overexpression of osteoinductive transcription factor Runx2/Cbfa1, Alpl, and senescence-associated molecules Tgfb1, Pai-1, p21, and Glb1. Here, we show that NH4Cl treatment in drinking water (0.28 M) prevented soft tissue and vascular calcification and increased the life span of kl/kl mice >12-fold in males and >4-fold in females without significantly affecting extracellular pH or plasma concentrations of 1,25(OH)2D3, Ca(2+), and phosphate. NH4Cl treatment significantly decreased plasma aldosterone and antidiuretic hormone concentrations and reversed the increase of Runx2/Cbfa1, Alpl, Tgfb1, Pai-1, p21, and Glb1 expression in aorta of kl/kl mice. Similarly, in primary human aortic smooth muscle cells (HAoSMCs), NH4Cl treatment reduced phosphate-induced mRNA expression of RUNX2/CBFA1, ALPL, and senescence-associated molecules. In both kl/kl mice and phosphate-treated HAoSMCs, levels of osmosensitive transcription factor NFAT5 and NFAT5-downstream mediator SOX9 were higher than in controls and decreased after NH4Cl treatment. Overexpression of NFAT5 in HAoSMCs mimicked the effect of phosphate and abrogated the effect of NH4Cl on SOX9, RUNX2/CBFA1, and ALPL mRNA expression. TGFB1 treatment of HAoSMCs upregulated NFAT5 expression and prevented the decrease of phosphate-induced NFAT5 expression after NH4Cl treatment. In conclusion, NH4Cl treatment prevents tissue calcification, reduces vascular senescence, and extends survival of klotho-hypomorphic mice. The effects of NH4Cl on vascular osteoinduction involve decrease of TGFB1 and inhibition of NFAT5-dependent osteochondrogenic signaling.

Urinary parameters predictive and electrolyte disturbances of cisplatin-induced acute renal associated with cancer as a critical target of the chemotherapeutic agent in patients with solid tumors.

Cisplatin (CP) is a remarkably effective Pt-based anticancer drug, but it also exhibits severe toxic side effects, including nephrotoxicity and ototoxicity, and CP nephrotoxicity is a major constraint for the treatment of solid tumors. This study was designed to evaluate the electrolyte and biochemical changes in dogs with acute kidney injury (acute renal failure) following administration of CP as a chemotherapeutic agent to exhibit broad efficacy in solid tumors. A total of 10 adult male dogs were selected (treated dogs = 7 and control dogs = 3). Cisplatin-treated animals were received 0.75 mg/kg via intravenous for 5 consecutive days. Urine and blood samples on days 0 (pre-dosing), 1, 2, 3, 4, 7, 10, 14, and 28 (post-dosing) were collected. For tracking the signs of toxicity with cisplatin, clinical examination was performed for 2 times a day. Serum samples were assayed urea, creatinine, sodium, chloride, potassium, calcium, phosphorus, and urine samples were used to measure creatinine. Serum creatinine levels indicating renal function (glomerular filtration rate) was 0.66 and 0.94 mg/dL in day 0, respectively, in treatment and control animals. After day 2, a significant change in creatinine was observed in treatment animals. On the end day of the study control and treatments, creatinine was measured with mean of 1.35 and 1.00 mg/dL, respectively. Electrolyte disturbances were observed after several days of cisplatin administration including changes in levels of sodium, potassium, phosphorus, calcium, and chloride. Clinical observations also identified CP toxicity. This study for the first time showed that compensation electrolyte abnormalities in dogs following administration of cisplatin is essential to prevent deaths by daily monitoring and measurement of electrolytes in patients. This may be advantageous if repetitive cycles of chemotherapy or subsequent administration of high dose chemotherapy were planned.