Enhanced intratumoral expression of RNF2 is a favorable prognostic factor for patients with cutaneous melanoma?

Recent studies involving melanoma cell lines suggest that enhanced expression of epigenetic regulator RNF2 supports proliferation and promotes metastasis. However, it is not clear to what extent those data apply to disease progression and prognosis for melanoma patients. Therefore the aim of the present study was to assess the prognostic power of RNF2 intratumoral expression by melanoma cells.

Prognostic significance of RBP2-H1 variant of JARID1B in melanoma.

Background: Histone demethylase JARID1B plays several context dependent roles in epigenetic regulation of cellular differentiation in normal development and is highly expressed in multiple human cancers. The protein is a strong transcriptional repressor capable of downregulating numerous genes. There are three splicing isoforms of JARID1B, however the links between the protein structure and function are not clear.

Intratumoral expression of cyclooxygenase-2 (COX-2) is a negative prognostic marker for patients with cutaneous melanoma.

Because of the well-known heterogeneity of melanomas, prognosis of the disease is often difficult to assess even for lesions classified in similar stages. The aim of this study was to assess the usefulness of COX-2 as a melanoma prognostic marker and to establish an optimum algorithm for analysis of COX-2 expression levels in lesions of interest. Expression of COX-2 was detected immunohistochemically in standard sections of formalin-fixed paraffin-embedded tissue samples of 85 primary melanomas, 36 lymph node metastases, and five skin metastases including 39 cases of paired primary and metastatic lesions obtained from the same patient.

Altered Splicing of JARID1B in Development of Human Cutaneous Melanoma?

Upregulated expression of histone H3K4 demethylase JARID1B has been found in several types of human cancer, but the expression pattern of this protein in benign naevi and human cutaneous melanomas seems to differ from that described for other tumors. We demonstrate that the apparent contradiction may be because of the fact that the malignant transformation of melanocytes is associated not so much with a general enhancement of a total expression of JARID1B but rather with a change in relative expression levels of individual splicing variants of the protein. Our data indicate that parallel immunohistochemical assays of the expression levels of all the isoforms and of the RBP2-H1 variant of JARID1B may be an efficient technique of differentiating between benign naevi and melanomas.

Stromal, rather than epithelial cyclooxygenase-2 (COX-2) expression is associated with overall survival of breast cancer patients.

Background: Prognostic value of enhanced COX-2 expression in breast cancer has been controversial for a long time. The opinions vary widely between studies. Moreover, significant majority of studies considered only COX-2 expression in cancer epithelial cells.

Different detectability of cyclooxygenase-2 (COX-2) protein in standard paraffin sections and tissue microarrays of human melanomas and naevi - comparative study.

Cyclooxygenase-2 (COX-2), overexpressed in many types of human cancer, may be a valuable marker for human melanoma. However, there are discrepancies between expression levels detected by different groups. The majority of the studies were carried out using standard paraffin sections.

JARID1B expression in human melanoma and benign melanocytic skin lesions.

It has been suggested that dynamically regulated expression of the JARID1B protein is required for the continuous growth of tumors and at the same time downregulated in melanoma. The majority of the data on a role of JARID1B in maintaining tumor growth has come from in-vitro and xenografting experiments, with only one immunohistochemical study involving human tissues. We compared JARID1B expression levels in human melanomas and benign nevi and analyzed patterns of spatial distributions of positive cells among different skin layers of the lesions.

The value of cyclooxygenase-2 expression in differentiating between early melanomas and histopathologically difficult types of benign human skin lesions.

Early cutaneous melanomas may present a substantial diagnostic challenge. We have already reported that expression of cyclooxygenase-2 (COX-2) may be useful for differentiating between cutaneous melanomas and naevi. The purpose of this study was to examine the value of COX-2 in a challenging task of differential diagnosis of early melanomas and melanocytic naevi considered by histopathologists as morphologically difficult to unequivocally diagnose as benign lesions.

Different expression of cyclooxygenase-2 (COX-2) in selected nonmelanocytic human cutaneous lesions.

The aim of our study was to elucidate the possible involvement of COX-2 in the development and/or progression of nonmelanocytic skin lesions. To evaluate the usefulness of that enzyme as a potential molecular marker, we examined the intensity and spatial distribution of COX-2 expression in selected types of such tumors using the same immunohistochemical procedure as in our earlier studies of melanocytic cancers. We examined 20 benign epithelial lesions, 11 precancerous lesions, 21 basal cell carcinomas (BCC), 14 squamous cell carcinomas (SCC) and eight fibromas.

Quantitative measurements of formalin-induced fluorescence for differential diagnostics of melanomas and lesions of human skin.

The usefulness of formaldehyde-induced fluorescence (FIF) for detection of melanoma cells has been suggested by several investigators during the last 40 years. FIF can be easily excited and observed in microscopic sections of formalin-fixed paraffin-embedded skin samples. However, such an approach has never been widely used in melanoma diagnostics for reasons including lack of clear diagnostic criteria, considerable inconsistencies in both the protocols used and qualitatively analysed results reported by different groups.

Cyclin-dependent kinase 2 (CDK-2) expression in nonmelanocytic human cutaneous lesions.

Lesions originating from different types of skin cells differ significantly with respect to their pathologic importance. The aim of this work was to examine as to what extent the differences in the origin are reflected in expression levels of CDK-2 and to investigate whether CDK-2 expression might be considered as potential marker useful for diagnostics and assessment of invasiveness of human nonmelanocytic lesions. We conducted comparative immunohistochemical studies of expression of cyclin-dependent kinase 2 (CDK-2) in 16 benign epithelial skin lesions, 11 precancerous lesions, 19 cases of basal cell carcinoma (first such study), 14 squamous cell carcinomas (SCCs), and 7 fibromas.

Porcine skin as a model system for studies of adverse effects of narrow-band UVB pulses on human skin.

Ultraviolet (UV) radiation has been widely used in medicine, and in recent years there has been a growing interest in narrow-band UVB therapies, especially those employing pulses of the 308-nm line of XeCl excimer lasers. Comparative studies in several skin pathologies showed that narrow-band UVB was more effective than classical broad-band UVB radiation. Simultaneously, UVB is carcinogenic and there is a need for data to establish the risk associated with phototherapies involving irradiations of human skin with different doses of narrow- and broad-band UVA and/or UVB radiation.

Cyclooxygenase-2 immunohistochemistry in human melanoma: differences between results obtained with different antibodies.

Several groups have reported that cyclooxygenase-2 (COX-2) expression is significantly enhanced in human melanomas, and that the expression of this protein may be useful as diagnostic and prognostic marker for the disease. At the same time, collective analysis of immunohistochemical data on the COX-2 expression in melanomas, presented by different researchers, shows a clear lack of consistency of reported results commonly assigned to differences in protocols used for the staining. This paper describes a study involving the parallel use of three different primary anti-COX-2 antibodies targeting different COX-2 epitopes.

Skin layer-specific Melan-A expression during progression of human cutaneous melanoma: implications for diagnostic applications of the marker.

Melan-A is widely used in the diagnostics of human melanoma. The immunogenicity of this glycoprotein makes it a potential target in immunotherapy and several authors have suggested its potential as a prognostic factor. Up to now there has been no clear direct evidence of changes of Melan-A expression during the progression of melanoma.

Cyclooxygenase-2 (COX-2): first immunohistochemical marker distinguishing early cutaneous melanomas from benign melanocytic skin tumours.

We have reported recently that changes in expression level of COX-2 are correlated with development and progression of human melanoma. In this study, we investigated whether the COX-2 expression level might be a useful immunohistochemical marker for distinguishing cutaneous melanomas from benign melanocytic lesions. Up to now, immunohistochemical markers have not ensured satisfactory sensitivity and specificity of differential pathologic diagnosis of melanoma.

Cyclin-dependent kinase 2 expression in human melanomas and benign melanocytic skin lesions.

Cyclin-dependent kinase 2 (CDK-2) is strongly involved in regulating the progression of the cell cycle through G1/S checkpoint and S phase. Numerous studies demonstrated increased levels of CDK-2 (and also of its regulatory cyclins E and/or A) in different types of human tumours. Correlations found between the expression of those cell cycle regulators and progression and/or invasiveness of some tumours indicated the importance of CDK-2 as a potential prognostic marker.

Porcine skin as a model system for studies of ultraviolet a effects in human skin.

The range of diagnostic and therapeutic applications of ultraviolet A (UVA) radiation has been continuously expanding. UVA radiation is a well-known mutagenic factor capable of damaging both cells and tissues. At the same time there is a very limited information on long-term consequences of irradiating the skin with different doses of UVA and long-wavelength ultraviolet B (UVB) radiation used in therapies of skin disorders.

Different expression of lysosome-associated membrane protein-1 in human melanomas and benign melanocytic lesions.

Lysosome-associated membrane protein-1 is a protein with a significant content of beta1,6-branched N-glycans. It is thought that enhanced expression of lysosome-associated membrane protein-1 in tumour cells may promote invasion by influencing both adhesion to extracellular matrix and perhaps also binding to endothelial cells. The present study was aimed at examining levels of lysosome-associated membrane protein-1 in human melanomas and benign pigmented lesions to evaluate whether this protein might be considered a potential molecular marker of melanoma progression.

Expression of cyclooxygenase-2 in benign naevi and during human cutaneous melanoma progression.

Cyclooxygenase-2 (COX-2) is an enzyme that plays an important role in the production of prostaglandins. Numerous studies have demonstrated increased levels of COX-2 in human cancers of different types. It is thought that COX-2 may be involved in the development and progression of malignant tumours.

Different susceptibility of cells of porcine skin and internal organs to ultraviolet A-induced breaking of nuclear DNA.

There is a continuously growing interest in medical applications of ultraviolet radiation (UV-A and long-wavelength UV-B) especially for laser surgery, phototherapy and photodiagnostics of human internal organs. UV-B and UV-A radiation is potentially mutagenic, however, there has been very little information published to date concerning the significance of possible deleterious action of such photons on cells of internal tissues. The aim of this study is to compare the sensitivities of skin cells to those of internal organs upon exposure to UV-A.

Variability of spectra of laser-induced fluorescence of colonic mucosa: its significance for fluorescence detection of colonic neoplasia.

To determine the extent of a natural variability of the spectra of the autofluorescence and its significance for a reproducibility of different approaches typically used in studies on fluorescence detection of colonic lesions. Two independent series of experiments have been conducted during three years in the same laboratory. Macroscopic tissue specimens obtained during operations of patients with colonic cancers were studied in vitro.