Analytical Cellular Pathology - Volume 30, issue 6 - Journals

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Tumour-associated transcripts and EGFR deletion variants in colorectal cancer in primary tumour, metastases and circulating tumour cells

Article Type: Research Article

Abstract: The clinical relevance of circulating tumour cells (CTC) in peripheral blood of patients with colorectal cancer (CRC) has been described as an independent prognostic factor useful to monitor drug effects and clinical status. The aim of the present study was to compare the epidermal growth factor receptor (EGFR) status of primary tumour, related metastases and CTC of patients with CRC. Therefore, in addition to EGFR, the tumour-associated transcripts gastrointestinal tumour-associated antigen 733-2 (GA733-2) and carcinoembryonic antigen (CEA) were analyzed in a multiplex RT-PCR to characterize CTC. 55% patients were positive for CTC. EGFR expression was detected in 18% of these …patients. EGFR was expressed more frequently in metastatic and primary tumour tissues as revealed by immunohistochemistry. Besides, detailed expression profiling of EGFR variants in various colorectal and glioma cell lines has been performed to generate positive controls, resulting in the discovery of two new transcript deletion variations (cEX12_15del, cEX12_14del) located on the extracellular domain of the EGFR. Show more

Keywords: Circulating tumour cells (CTC), colorectal cancer, RT-PCR, immunomagnetic enrichment, EGFR, EGFR variants

DOI: 10.3233/CLO-2008-0432

Citation: Analytical Cellular Pathology, vol. 30, no. 6, pp. 463-471, 2008

Price: EUR 27.50

Immunohistochemical detection and localization of somatostatin receptor subtypes in prostate tissue from patients with bladder outlet obstruction

Article Type: Research Article

Abstract: Background and aim of the study: Scant information on the cellular distribution of the five somatostatin receptor (SSTR) subtypes in the normal prostate and in neoplasms of the prostate has been reported in very few studies in which techniques, such as in situ hybridization histochemistry, autoradiography, and more recently immunohistochemistry, have been applied. The aim of the study was to examine immunohistochemically the distribution and localization of these 5 subtypes in the various tissue components in normal prostate. Materials: The study was conducted in 14 surgical specimens of normal prostate tissue from adenomectomy specimens from patients with bladder outlet …obstruction. The distribution and localization of the 5 somatostatin receptor (SSTR) subtypes was investigated with an immunohistochemical technique. Specificity of the antibodies against the 5 receptor subtypes was preliminarily investigated. Results: Close to 90% of secretory cells showed a weak positivity in the cytoplasm, the proportion ranging from 86.3% (SSTR4) to 89.9% (SSTR5). Strong immunoreactivity was seen in a small proportion of cells, ranging from 0.8% (SSTR3) to 3.2% (SSTR1). For the subtypes 1 and 3 the greatest proportion of basal cells showed a moderate intensity (42.5 and 41.4%, respectively), strong immunoreactivity being observed only in 18.1 and 15.8% of cells, respectively. For the subtypes 2, 4 and 5, the majority of cells showed a weak intensity (72.3, 65.7 and 65.1%, respectively). Subtype 1 showed a strong immunoreactivity in the cytoplasm in 60% of the smooth muscle cells. With subtypes 2, 3 and 4 the greatest proportion of cells showed a weak intensity (63.4, 89.8 and 81.7%, respectively). With the subtype 5 the majority of cells (59.8%) were negative. Subtype 1 showed a strong immunoreactivity in the cytoplasm in 98.6% of the endothelial cells. With subtypes 3 and 4 the greatest proportion of cells showed a weak intensity (73.5 and 56.4%, respectively). With the subtype 2 and 5 the majority of cells were negative (59.1 and 50.7%, respectively). Show more

DOI: 10.3233/CLO-2008-0433

Citation: Analytical Cellular Pathology, vol. 30, no. 6, pp. 473-482, 2008

Price: EUR 27.50

Relationship between dyskerin expression and telomerase activity in human breast cancer

Article Type: Research Article

Abstract: The nucleolar protein dyskerin is involved in the modification of specific uridine residues to pseudouridine on ribosomal and small nuclear RNAs and in the stabilization of the telomerase RNA component (TERC). In this study we investigated for the first time the relationship between dyskerin expression and telomerase activity in a series of 61 primary breast carcinomas. We found that when dyskerin mRNA values were very low the telomerase activity was markedly reduced, independently of the expression of other important components of the telomerase complex such as telomerase reverse transcriptase (TERT). In vitro experiments showed that reduction of dyskerin expression affect …telomerase activity through the reduction of TERC. Only when TERC levels were strongly reduced telomerase activity was hindered. Retroviral mediated over-expression of TERC abolished the telomerase impairment due to dyskerin knock down. In conclusion, our results indicated that, beside its effect on ribosome biogenesis, the levels of dyskerin in cancer cells modulate telomerase activity through the regulation of TERC levels, independently of TERT expression. This should be taken into consideration when utilizing TERT expression as a surrogate indicator of telomerase activity in tumour pathology. Show more

Keywords: Breast carcinomas, dyskerin, telomerase, TERC, TERT

DOI: 10.3233/CLO-2008-0436

Citation: Analytical Cellular Pathology, vol. 30, no. 6, pp. 483-490, 2008

Price: EUR 27.50

The doppel (Dpl) protein influences in vitro migration capability in astrocytoma-derived cells

Article Type: Research Article

Abstract: Doppel (Dpl) protein is the paralogue of the cellular prion (PrPC ) protein. In humans, Dpl is expressed almost exclusively in testis where it is involved in spermatogenesis. Recently, the protein has been described to be ectopically expressed in astrocytomas and its potential association to the brain tumor malignancy progression has been advanced. In this study, we aimed to investigate in vitro the potential involvement of Dpl in the tumor cell migration: to this purpose, Dpl expression was reduced in the IPDDC-A2 astrocytoma-derived cell line, by means of antisense and siRNA approaches; migration rates were then evaluated by means of …a scratch wound healing assay. As a result, the cellular migration was sensibly reduced after Dpl silencing. Following a complementary approach, in HeLa cells, showing very low endogenous Dpl expression, the protein expression was induced by transfection and stabilization of an eukaryotic expression vector containing the doppel gene coding sequence. These stably Dpl-overexpressing cells revealed a significant increase in the migration rate, compared to untreated and control cells. In addition, Dpl-forced expression induced substantial changes in the cell morphology. Of note, in these cells, viability examination by means of tetrazolium-based assay did not reveal differences in the proliferation; on the contrary, a variation in density-dependent growth, leading to an increase of cell contact inhibition was highlighted. These results, in conclusion, might suggest a potential and functional role for Dpl in tumor cells migratory and morphological behaviours and address to future gene-targeted therapeutic interventions. Show more

Keywords: Prion-like proteins, glial tumor, IPDDC-A2, HeLa, siRNA, antisense oligonucleotide, gene-silencing, migration scratch assay

DOI: 10.3233/CLO-2008-0437

Citation: Analytical Cellular Pathology, vol. 30, no. 6, pp. 491-501, 2008

Price: EUR 27.50