Ghrelin expression of endometrium hyperplasia and endometrioid carcinoma.

BACKGROUND: Endometrium carcinoma ranks fourth among female carcinomas. Therefore, early diagnosis of endometrium pre-malignant lesions is emphasised, and attempts are made to identify the risk factors. Since hyperplasias, particularly those with atypia, are held responsible for the development of the most common endometrium carcinomas, it is important to definitely distinguish between well-differentiated carcinomas and hyperplasia with atypia. In the present study, we aimed to explore whether ghrelin expression had a role in distinguishing between benign, pre-malignant and malignant lesions of endometrium. METHODS: Tissue ghrelin expressions of a total of 60 cases, who were diagnosed in the Pathology Department Laboratory of Firat University Medical School, and of whom 10 were in the proliferation phase, 10 had simple hyperplasia without atypia, 10 had simple hyperplasia with atypia, 10 had complex hyperplasia without atypia, 10 had complex hyperplasia with atypia and 10 had endometrioid carcinoma cases, were examined using immunohistochemical method. Additionally, tissue samples were homogenised to analyse tissue ghrelin levels in the supernatants according to RIA method. Samples from the parotid glands were used as positive control for ghrelin. Cells that exhibited cytoplasmic staining with ghrelin antibody were evaluated as positive. RESULTS: Immunohistochemical examination showed that ghrelin expression increased markedly in the proliferation phase, relative to hyperplasias and carcinoma. These results were parallel to ghrelin levels in tissue supernatants. Immunohistochemical and RIA analysis results indicate that ghrelin expression either markedly decreases or is entirely depleted in endometrial carcinomas. CONCLUSIONS: Therefore, we think that ghrelin expression can be useful in differentiating not only endometrium carcinomas from benign lesions but also complex hyperplasias with atypia, which pose diagnostic difficulties.

Ghrelin and obestatin expression in oral squamous cell carcinoma: an immunohistochemical and biochemical study.

The underlying molecular mechanism of carcinogenesis in oral squamous cell carcinoma (OSCC) is poorly understood and appears to be controlled on many genetic, environmental, and hormonal factors. Obestatin and ghrelin, two recently discovered hormones, are co-expressed in endocrine cells. The purpose of this investigation was to examine the immunohistochemical features of OSCCs in relation to the tissue concentration of ghrelin and obestatin. The association between OSCC and Epstein Barr Virus (EBV) status was also explored. The expression of ghrelin and obestatin was examined by immunohistochemistry and immunoassay in oral biopsy specimens: 10 benign squamous epithelial cell samples, 10 microinvasive squamous cell carcinomas, and seven well-differentiated and seven poorly differentiated OSCCs. The presence of EBV was evaluated in these samples using immunohistochemistry. The concentrations of ghrelin and obestatin in tissue homogenates were measured by RIA and ELISA, respectively. Squamous cell carcinomas and benign tissue samples were positive for anti-EBV antibody, and obestatin and ghrelin were shown to be co-expressed in all stratified squamous epithelium samples. Expression of ghrelin and obestatin was decreased or absent in OSCCs in relation to the invasiveness of the carcinoma; ghrelin and obestatin levels in cancerous tissue homogenates were lower than in benign tissue homogenates. These results indicate that the concentrations and distribution of immunoreactive obestatin and ghrelin might be helpful in distinguishing OSCC from benign tumors. Maintaining normal levels of these hormones might be required for regulation of normal cell division. However, detailed studies will be required for better understanding of the complex mechanism of carcinogenesis relating to OSCCs.

Ghrelin expression in normal kidney tissue and renal carcinomas.

Ghrelin expression in cancers is either reduced/absent or increased depending on the organs involved. The aims of this study were to investigate: (i) whether there are differences in ghrelin peptide expression between kidney tissues from a series of renal cell carcinoma cases, oncocytomas, and normal controls; (ii) whether there are correlations between tissue ghrelin levels in a series of renal carcinoma cases and normal controls; and (iii) how normal is kidney ghrelin expression per mg tissue as compared with the normal stomach tissue ghrelin level. We studied 7 normal stomach and 7 normal kidney samples, 21 clear cell renal carcinomas, 7 chromophobe type renal cell carcinomas (RCC), 7 papillary type RCC, and 7 oncocytoma samples. Tissue ghrelin expression was measured by RIA and immunohistochemistry. Grades 1-3 clear renal cell carcinomas, chromophobe type RCC, papillary type RCC, and oncocytomas expressed 88%, 94%, 95%, 51%, 75%, and 48% less ghrelin than the normal kidney, respectively. Overall, we concluded that ghrelin expression in renal cell carcinoma tissues is always lower than that in normal kidney or is absent. This low level or lack of ghrelin may play a role in the etiopathogenesis and progression of cancer.