Pathological alterations of renal function in insulindependent diabetes have been attributed to numerous factors, including adenosine. This study examined the expression levels of adenosine receptors (ARs) in the kidney of the streptozotocin-induced diabetic rat. In the diabetic kidney A1-AR mRNA levels increased 1.7-and 2.8-fold in cortex and medulla, respectively. This was accompanied by increased A1-AR protein levels in membranes of kidney cortex (1.5-fold) and medulla (threefold). A1-AR immunoreactivity increased strongly along medullar tubules especially in the collecting duct. The levels of A2a-AR mRNA increased twofold in diabetic kidney cortex but remained unchanged in medulla; however, A2a-AR protein levels increased more than threefold in cortex. Immunohistochemistry showed increased A2a-AR immunoreactivity in luminal membranes of cortical collecting ducts and in epithelial cells of preglomerular vessels. There were no significant changes in A2b-AR expression in diabetic kidney except in medullar membranes, where the receptor protein content decreased by 60%. A3-AR mRNA levels in diabetic kidney remained unchanged, but membrane-associated A3-AR protein levels increased by 70% in diabetic kidney cortex and decreased by 80% in medulla. These changes in ARs genes expression, receptor protein content, and cellular and tissue distribution, correspond to abnormalities characteristic of the diabetic kidney, suggesting involvement in pathogenesis of diabetic nephropathy. Kidney disease is one of the leading hallmarks of human diabetes. It is characterized by persistent proteinuria, hypertension, and progressive loss of renal function. 1These changes are preceded by glomerular hyperfiltration, which is an early symptom in the development of diabetic nephropathy.2,3 Pathological changes of renal function in insulin-dependent diabetes have been attributed to numerous factors, including impaired action of angiotensin II, NO, prostaglandins, and adenosine. 4 -7 Adenosine in the kidney plays a broad regulatory role including modulation of renal blood flow, glomerular filtration rate, hormone and neurotransmitter release, transport function, and urine flow.8 Therefore, any changes in its action may significantly affect function of this organ.Adenosine is formed both in the extra-and intracellular space and exerts its physiological effect by coupling to cell-surface receptors, namely A1, A2a, A2b, and A3. The affinity for adenosine varies between receptors; thus its activation depends on adenosine concentration. The level of adenosine depends on its metabolism and transport across plasma membranes. Our previous studies showed that, except for ENT2, the expression level of nucleoside transporters in kidney of diabetic rats was not altered. 10 Moreover, the expression level of adenosine kinase in the diabetic kidney was greatly reduced, suggesting that the turnover of the adenosine-AMP metabolic cycle might be impaired under diabetic conditions. 11
A soluble complement inhibitor factor H (FH) and its splice variant factor H-like protein (FHL) have been recently discovered to play a major role in malignant cell escape from complement-mediated cytotoxicity in lung-, ovarian-and glia-derived neoplasms. The role of FH in colon cancer has not yet been examined. Here, we studied immunocytochemically FH/FHL expression in tumor samples derived from 40 patients, with both primary colon adenocarcinoma and metastatic foci in the liver. FH/FHL immunoreactivity was present in stroma of both primary and metastatic tumors, in virtually all patients. The cellular immunoreactivity was observed infrequently. Importantly, when analyzed quantitatively, FH/FHL immunoreactivity was significantly increased in liver metastases when compared with the primary sites. In addition, we have analyzed FH and FHL expression in 5 colon cancer cell lines: SW480, SW620, HCT116, HT-29 and Lovo. FH mRNA and FH secretion were observed in SW620 and HT-29 cells, whereas FHL was produced only by HT-29 cell-line. By confocal and electron microscopy, FH immunoreactivity was associated with the plasma membrane and intracellular vesicular structures. Finally, we have analyzed the role of FH in the susceptibility of SW620 colon cancer cells to complement-mediated damage. When FH function was blocked, using specific antibody, the cells became more susceptible to lysis. Taken together, our results suggest an important role of FH/FHL in colon cancer cells defense against complement-mediated cytotoxicity, and in metastatic process. ' 2008 Wiley-Liss, Inc.Key words: factor H; colon cancer; metastasis; immunotherapy; complement Although recent years have brought many advances in clinical oncology, colon cancer is still a serious problem. Surgical resection remains as the most efficient treatment, but its results are often not satisfactory. Sixty percent of patients with colon cancer develop liver metastases, which, for a third of those, is the main and only metastatic site. About 25% of the patients have potentially resectable hepatic metastases, but at least half of them have recurrence after surgery. 1 Unfortunately, for a large group of patients, radical surgery is impossible. For about 60% of such patients, advanced chemo-and radiotherapy allows for a 5-year survival, however a major objection to this kind of treatment is severe side effects. 2 To improve disease-free survival, overall survival and to prevent formation of metastases, new strategies for effective treatment should be considered.
The assessment of NDRG1 expression offers valuable prognostic information for patients with colorectal cancer, especially for those with stage II disease. We propose that NDRG1 expression level could be used to select patients with stage II disease who are at increased risk of unfavorable outcome, and who may benefit from adjuvant therapy.
Abstract. Estimation of HER2 membranous expression is routinely used in breast and gastric cancers, as both a prognostic and a predictive factor. To date there is no evidence for similar application of HER2 expression in colorectal cancer (CRC) cells. In CRC, HER2 is sometimes overexpressed in the cell membrane and very often in the cytoplasm. This study was conducted to determine possible correlations between both membranous and cytoplasmatic expression of HER2 in CRC cells and the outcome of the disease. The prognostic significance of combined staining intensity in the cell membrane and cytoplasm in the entire CRC cell was also investigated. HER2 expression in resectable colorectal adenocarcinoma cells was evaluated by immunohistochemistry in specimens taken from 202 patients. The percentage of cancer cells with membranous or cytoplasmatic reactions and the staining intensity of the reaction in the whole cell were recorded. A membranous reaction was present in 27% of cases, and cytoplasmatic reaction in 66% of cases. The total staining intensity in the entire cell was evaluated as moderate (2+) in 32% of cases and strong (3+) staining in 15%. There was no correlation found between either membranous or cytoplasmatic HER2 expression and survival. Furthermore combined staining intensity did not provide any prognostic information. We conclude that HER2 expression in CRC does not correlate with prognosis.
Nonalcoholic steatohepatitis (NASH), which is the most severe histologic form of nonalcoholic fatty liver disease (NAFLD), is emerging as the most common clinically important form of liver disease in obese patients. The prevalence of NASH may increase with the rise in the rate of obesity and metabolic syndrome in affluent communities. The aim of this work is to describe clinical and histopathologic findings and correlate liver tissue damage to the length of duration of the obesity in the group of patients who underwent surgery as obesity treatment. Eighty-seven severely or morbidly obese patients underwent gastroplasty. Each patient was evaluated with complete clinical and laboratory medical assessment together with wedge liver biopsy taken from 59 unselected patients during the surgery. Patients were followed up for 41 months. Repeat liver biopsy was taken from 10 patients. Pathologic analysis recorded the presence and degree of steatosis, portal and lobular inflammation and fibrosis. Age, body mass index (BMI), and laboratory assessment correlated with pathologic data. Male patients showed more pronounced metabolic syndrome and fatty liver damage. Patients who become obese in childhood or as teenagers showed no differences in metabolic syndrome and NAFLD in mature age. There was statistically significant association between BMA, elevated transaminases, NAFLD, and fibrosis. Significant weight reduction was observed within first year after surgery, was slower in the second year, and stabilized within third year. Remarkable improvement followed in biological markers of metabolic syndrome. Ninety-six percent of initial liver biopsies had steatosis; 16% developed steatohepatitis and mild perivenular fibrosis. Significant improvement of the degenerative and inflammatory hepatic lesions in repeated biopsies and liver function readings was noted within 8 months after surgery. Obesity is a major and independent risk factor for the metabolic syndrome, NAFLD, NASH, and fibrosis. Surgical treatment improves metabolic abnormalities and hepatic lesions in long-term observations.
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