Epidermal growth factor receptor (EGFR) status in chordoma.

Chordoma is a rare tumour arising from the embryonal remnants of a notochord occurring most commonly in the sacrococcygeal as well as head and neck locations. Current treatment includes surgery and/or proton beam radiotherapy. In several cases especially in the head and neck location, surgery is not advised. Proton beam therapy is not always effective enough to eradicate the tumour. Additional modes of therapy are needed. One of the current therapeutic approaches in various tumours is targeted therapy and one of the targets is EGFR. The aim of this study was to evaluate EGFR expression and EGFR gene status of chordoma. Twenty-one cases of chordoma were retrieved from the in-house and consultation files of the Maria Sklodowska-Curie Memorial Cancer Centre and Institute of Oncology in Warsaw. Immunohistochemistry with an anti-EGFR antibody and FISH was performed on slides obtained from representative archival paraffin blocks. In our study 81% of cases of chordoma showed low to high EGFR expression in immunohistochemistry. In six cases (26.6%) the FISH results for EGFR were classified as positive (an average EGFR copy number > or = 4 per cell). There was one case of chromosome 7 aneuploidy reported.

Her2, EGFR and TOPIIA gene amplification and protein expression in synovial sarcoma before and after combined treatment.

Synovial sarcoma (SyS) occurs mostly in young adults and is characterized by an aggressive course. Combined treatment including chemotherapy, radiotherapy and surgical excision of the tumour is still not satisfactory, with mean 5-year survival of 30-50%. New targeted treatment options have appeared recently, e.g. HER2 and EGFR antagonists. Initial studies have revealed immunohistochemical overexpression of the EGFR in SyS; therefore trials with EGFR antagonist therapy have commenced. The aim of our study was to evaluate the status of HER2, EGFR and TOPIIA in SyS before and after combined therapy. Immunohistochemistry and FISH tests were performed. Significant discrepancies between protein expression and gene status were found. The authors discuss the potential reasons for that phenomenon.

Intracellular second messengers involved in melatonin signal transduction in chicken splenocytes in vitro.

The pineal hormone melatonin exhibits immunomodulatory activity well documented in mammals and birds. The mechanism of melatonin action within the immune system is, however, poorly understood. In mammalian immune cells in vitro, melatonin acts mainly as an antiapoptotic, oncostatic and antiproliferative agent, and these effects are exerted via specific receptors or are related to its free radical scavenging activity. In previous studies we have found that in short-term chicken splenocyte cultures in vitro melatonin stimulated basil proliferation and inhibited that stimulated with phytohemagglutinin, a T-cell mitogen. This paper is devoted to the involvement of membrane receptors, previously characterised by us as MT2 (Mel(1b)) and Mel(1c) subtypes, in the above mentioned melatonin effects in chicken splenocyte cultures. For this purpose, in present study a nonselective melatonin receptor antagonist, luzindole, and the selective MT2 blocker, 4P-PDOT, were used. The effect of melatonin on second messengers, cyclic adenosine-3',5'-monophosphate (cAMP) and inositol-1,4,5-trisphosphate (IP(3)), involved in the regulation of proliferation, was examined. We have found that the stimulation of proliferation occurs via Mel(1c) receptor and is associated with the changes in intracellular second messengers concentration: a decrease in cAMP and an increase in IP(3). In contrast, in mitogen-activated splenocytes, melatonin-induced inhibition of proliferation is mediated by MT2 receptors and is related to cAMP accumulation, as well as a decrease in IP(3). In conclusion, we have demonstrated that the stimulatory and inhibitory effect of melatonin on chicken splenocytes in vitro, dependent on the magnitude of cell stimulation, resulted from two different subtypes of membrane receptors.

HER2 status in breast cancer determined by IHC and FISH: comparison of the results.

HER2 (human epidermal growth factor receptor 2) status became an important prognostic and predictive factor in breast carcinoma clinical management. There are two main techniques of evaluation of HER2 status: immunohistochemistry (IHC) for the protein expression and fluorescence in situ hybridization (FISH) for amplification of HER2 gene. The aim of the study was to compare the results obtained by IHC and FISH methods in determination of HER2 status in breast cancer. Three hundred and sixty breast cancer specimens were examined. Patients were operated in the Oncology Centre in Warsaw. IHC and FISH were performed in every case. IHC was performed with DAKO HercepTest and FISH with Oncor-QBiogene reagents. IHC results were classed into 4 groups, accordingly to the four-tier DAKO criteria system (0, 1+, 2+, 3+). FISH results were divided into three main categories: NA--no amplification, LA--low amplification and HA--high amplification. The number of copies of chromosome 17 was also assessed. Over 90% of cases described by IHC as 3+ exhibited amplification of HER2/neu gene. Remaining cases were positive with IHC, but presented no gene amplification. This might be due to the subjective assessment of the membrane staining. Another possibility is that overexpression of the protein was caused by mRNA stability or disorders in receptor degradation. The majority of cases classed by IHC as 2+ were also negative by FISH (80%). One fifth of IHC 2+ tumours were found to exhibit gene amplification. Remaining cases showed no amplification of HER2/neu gene, combined with aneuploidy of chromosome 17. All cases described by IHC as 0/1+ were also HER2-negative by FISH. IHC is well-established method of assessing HER2 status in breast cancer. Nonetheless, a group of cases described as 2+ should be additionally examined using FISH. The results obtained by the latter method are more reliable. In order to improve accuracy and gain the highest quality of HER2 status evaluation, in 2+ cases both methods should be applied.

Influence of melatonin on chicken lymphocytes in vitro: involvement of membrane receptors.

OBJECTIVES: Time-dependent melatonin effects on chicken lymphocyte proliferation in vitro and the involvement of cAMP in melatonin signal transduction were examined. MATERIALS AND METHODS: Splenocytes and peripheral blood mononuclear cells (PBMC) were cultured in vitro in the presence of melatonin, phytohemagglutinin, luzindole, dibutyrylcAMP (dbcAMP), forskolin and vasoactive intestine peptide (VIP). Proliferation was measured by [(3)H]-thymidine incorporation in cultures carried out for 24, 36, 48 and 72 h. Cyclic AMP formation was assessed by radioimmunoassay in cells incubated for 30 min. or 24 h. RESULTS: Melatonin stimulated the spontaneous proliferation in short-term (36 and 48 h) splenocyte cultures and had no effect in 72 h cultures. It inhibited mitogen-stimulated proliferation already in 24 h cultures and this effect was observed regardless of the time of the culture. Both melatonin effects were antagonized by luzindole - membrane-bound melatonin receptor antagonist. Forskolin and dbcAMP caused a significant inhibition of proliferation of splenocytes and PBMC cultured for 24 or 72 h, respectively. Melatonin inhibited the cAMP formation (30 min. of incubation) stimulated by adenosine cyclase activators - forskolin and VIP, but added alone failed to affect the cAMP concentration. In mitogen-stimulated splenocytes cultured for 24 h Mel caused an increase in cAMP correlated with the inhibition of cell proliferation. CONCLUSIONS: Melatonin effects on chicken splenocytes appears time- and activation-dependent: in short-term cultures it stimulates spontaneous and inhibits mitogen-activated proliferation, probably via membrane-bound, luzindole-sensitive melatonin receptors. Incubation with melatonin for 30 min. inhibits cAMP formation, but in 24 h cultures it increases cAMP concentration leading to inhibition of proliferation.