Expression and prognostic values of Id-1 and Id-3 in gastric adenocarcinoma.

BACKGROUND: Id (inhibitor of differentiation/DNA binding)-1 and -3 are involved in neoangiogenesis; they antagonize basic helix-loop-helix proteins, inhibit differentiation, and enhance cell proliferation. The aim of this study was to investigate Id-1 and -3 expression in gastric tumors and their clinical relevance in gastric cancer. MATERIALS AND METHODS: We investigated Id-1 and Id-3 expression in gastric cancer samples by immunohistochemistry and Western blotting, and further analyzed the relationship between expression of Id-1 and Id-3 and clinicopathologic characteristics. RESULTS: Expression of Id-1 and -3 was found significantly more often in gastric cancers than in matched adjacent nonmalignant tissues. Cancer samples with poor or moderate histologic differentiation showed significantly stronger Id-1 and -3 expression than cancer samples with high differentiation. In cancer samples, strong or moderate expression of Id-3, but not Id-1, was a strong independent predictor for shorter overall survival in multivariate analysis. CONCLUSIONS: The level of Id-1 and -3 protein expression was associated with the malignant potential of gastric tumors. In cancer samples, stronger Id-1 and -3 expression is associated with poor differentiation and more aggressive behavior of tumor cells, resulting in poor clinical outcome. Consequently, Id-3 might be used to independently predict survival of patients with gastric cancer.

Protective treatments and their target retinal ganglion cells in diabetic retinopathy.

Diabetic retinopathy(DR)is one of the complications of diabetes which could cause severe vision loss. Retinal ganglion cell(RGC)injury has been confirmed prior to micro-vascular damage. Over the past few decades, a number of animal and clinical studies have confirmed that RGC impairment leads to an early deterioration of vision in DR. Inhibition of aldose reductase (AR), advanced glycation end product (AGE), oxidative stress, glutamate toxicity, and an inflammatory response may play important roles in protecting RGCs in DR. Furthermore, nicotinamide mononucleotide adenylyl transferase-1 (Nmnat1), neurotrophins and neurotrophic factors may become new therapeutic targets. Photobiomodulation (PBM) may be used as adjunctive therapy in protective treatment of RGCs. In this review, we highlight and discuss protective treatments and their targets which have shown great promise for treatment of RGC injury in DR.

Function of obestatin in the digestive system.

Physical health has a direct relationship with digestive function. Any abnormalities in the link may cause malnutrition, endocrine disorders, and the decline of organ functions. Obestatin, a biologically active peptide, is encoded by the ghrelin gene. Most studies suggest that obestatin is a pleiotropic peptide, which acts by suppressing the motility of the gastrointestinal tract, regulating the secretion of insulin, reducing inflammation and apoptosis, and promoting proliferation. These characteristics suggest that obestatin may represent an efficient way to prevent the occurrence and development of some digestive diseases. However, the functions of obestatin are not clear, and even appear to be contradictory. The aim of this review was to discuss the close relationship between obestatin and the digestive system, and to provide a unique perspective for the future development of obestatin relative to digestive diseases.

Hepcidin and iron metabolism in non-diabetic obese and type 2 diabetic rats.

The aim of this study was to investigate the changes of iron levels and hepatic regulatory molecules expression involved in iron metabolism in non-diabetic obese/type 2 diabetic rat models. Male Wistar rats were divided into 3 groups: control group, non-diabetic obese group and type 2 diabetic group (n=20 each). The rats were evaluated physiologically and biochemically. The hepatic histopathological changes were observed using haematoxylin and eosin (HE) staining. The mRNA expression patterns of hepcidin, interleukin-6 (IL-6), hypoxia-inducible factor (HIF) and ferroportin (Fpn) in the rat liver in control group, non-diabetic obese group and type 2 diabetic group were analyzed by real-time RT-PCR. The protein expression patterns of hepcidin in liver of each group were further analyzed by immunohistochemistry and Western blotting. As compared with control group, the ferritin in non-diabetic obese group and type 2 diabetic group was increased significantly (P<0.001). However, there was no significant difference in soluble transferring receptor (sTfR):ferritin ratio among the three groups (P>0.05). The real-time RT-PCR, immunohistochemistry and Western blotting results all revealed that the expression levels of hepcidin in non-diabetic obese group and type 2 diabetic group were elevated significantly as compared with those in control group (P<0.001). The expression levels of hepcidin mRNA between non-diabetic obese group and type 2 diabetic group showed no significant difference (P>0.05). However, the protein expression levels of hepcidin in type 2 diabetic group were significantly higher than those in non-diabetic obese group (P<0.05). Compared to control group, the expression levels of IL-6 mRNA in non-diabetic obese group and type 2 diabetic group were increased significantly and the expression levels of Fpn mRNA decreased (P<0.05). However, the expression levels of HIF mRNA had no significant difference among three groups. It is suggested that iron metabolism is substantially disturbed in non-diabetic obese and type 2 diabetic rats probably by the abnormal expression of hepcidin in chronic inflammatory status. The increased hepcidin may restrain the iron release from the cells by affecting the expression of Fpn, which probably associates with the development of diabetic complication.

Expression and prognostic value of ING3 in human primary hepatocellular carcinoma.

The tumor-suppressor ING3 has been shown to be involved in tumor transcriptional regulation, apoptosis and the cell cycle. Some studies have demonstrated that ING3 is dysregulated in several types of cancers. However, the expression and function of ING3 in human hepatocellular carcinoma (HCC) remains unclear. The aim of this study is to investigate ING3 expression in hepatic tumors and its clinical relevance in hepatic cancer. The expression of ING3 protein was examined in 120 dissected HCC tissues and 47 liver tissues adjacent to the tumor by immunohistochemical assays and confirmed by Western blot analysis in 20 paired frozen tumor and non-tumor liver tissues. The relationship between ING3 staining and clinico-pathological characteristics of HCC was further analyzed. The mRNA expression of ING3 in the dissected tissues was also analyzed by reverse transcriptase polymerase chain reaction (RT-PCR) and realtime PCR. Both mRNA and protein concentrations of ING3 were found to be downregulated in the majority of HCC tumors in comparison with matched non-tumor hepatic tissues. Analysis of the relationship between ING3 staining and clinico-pathological characteristics of HCC showed that the low expression of ING3 protein is correlated with more aggressive behavior of the tumor. Kaplan-Meier curves demonstrated that patients with a low expression of ING3 have a significantly increased risk of shortened survival time. In addition, multivariate analysis suggested that the level of ING3 expression may be an independent prognostic factor. Our findings indicate that ING3 may be an important marker for human hepatocellular carcinoma progression and prognosis, as well as a potential therapeutic target.

Relationship between down-regulation of HIC1 and PTEN genes and dysfunction of pancreatic islet cells in diabetic rats.

The aim of the study was to investigate the protein expression of hypermethylated in cancer 1 (HIC1 ) and phosphatase and tensin homologue (PTEN) genes and to study their mRNA expressions in normal and diabetic pancreatic islet cells in rats in order to try and identify the functions of these genes in the development and advancement of diabetes. We further aimed to analyze the expression of mammalian target of rapamycin (mTOR), which is regulated by PTEN and to investigate the possible mechanism of PTEN affecting the function of diabetic islet cells. The expressions of HIC1, PTEN and mTOR genes were examined in the pancreatic islets of 20 normal male Wistar rats and 47 diabetic male Wistar rats by immunohistochemistry, Western blot, RT-PCR and real-time RT-PCR. Results showed that expressions of HIC1 and PTEN in protein and mRNA levels were lower in pancreatic islets of diabetic rats than in normal rats. Expressions of mTOR in protein and mRNA levels were higher in pancreatic islets of diabetic rats than in the normal rats. Marked apoptosis of pancreatic islet cells was observed in 29 cases (29/47, 61.7%) in diabetic rats, but not in the remaining 18 (18/47, 38.3%) diabetic rats. The down-regulation of HIC1 and PTEN and up-regulation of mTOR in protein and mRNA level are positively correlated with functional impairment of islet cells in diabetic rats. From this study we conclude that HIC1, PTEN and mTOR cannot be recognized as the key influencing factors promoting pancreatic islet cells apoptosis of diabetic rats; however, lower expressions of HIC1 and PTEN and higher expression of mTOR may affect the function of the pancreatic islet cells in diabetic rats.

Expression and prognostic value of Id protein family in human breast carcinoma.

Inhibitors of DNA binding/inhibitors of differentiation (Id) protein family (Id-1, -2, -3 and -4) of helix-loop-helix proteins have been shown to be involved in carcinogenesis and are regarded as prognostic markers in several types of human cancers. However, the roles of Id proteins during breast carcinoma progression remain unclear. The objective was to study the effects of Id proteins in breast cancer. The expression of Id-1, Id-2, Id-3 and Id-4 proteins was examined in 122 dissected female human breast carcinoma tissues and 22 normal female breast specimens by immunohistochemical assay and the relationship between Id staining and clinical pathological characteristics of breast cancer was also analyzed. The over-expressed Id-1 and down-regulated Id-4 proteins were found both correlated with poorer differentiation and more aggressive behavior of the tumor. Id-1 protein could be termed as a negative prognostic marker while Id-4 protein as a positive marker for patients with breast carcinoma. Although the differentially expressed Id-2 and -3 may be correlated with some clinical parameters, they could not be used as independent prognostic factors in human breast cancer.