-
Peter Balla,
Linda Moskovszky,
Zoltan Sapi,
Ramses Forsyth,
Helen Knowles,
Nick A Athanasou,
Miklos Szendroi, Laszlo Kopper,
Hajnalka Rajnai,
Ferenc Pinter,
Istvan Petak,
Maria Serena Benassi,
Piero Picci,
Amalia Conti,
Tibor Krenacs
[show abstract]
[hide abstract]
ABSTRACT: Epidermal growth factor receptor (EGFR) is implicated in bone remodelling. The aim was to determine whether EGFR protein expression contributes to the aggressiveness and recurrence potential of giant cell tumour of bone (GCTB), an osteolytic primary bone tumour that can exhibit markedly variable clinical behaviour.
Immunohistochemical analysis on tissue microarrays (TMA) of 231 primary, 97 recurrent, 17 metastatic and 26 malignant GCTBs was performed using TMA analysis software and whole digital slides allowing validated scoring. EGFR expression was restricted to neoplastic stromal cells and was significantly more frequent in recurrent (71 of 92; 77%) than in non-recurrent GCTBs (86 of 162; 53%) (P = 0.002); and in clinicoradiologically aggressive (31 of 43; 72%) than latent (27 of 54; 50%) cases (P = 0.034). Detecting phosphotyrosine epitopes pY1068 and -pY1173 indicated active EGFR signalling, and finding EGFR ligands EGF and transforming growth factor-α restricted to cells of the monocytic lineage suggested paracrine EGFR activation in stromal cells. In functional studies EGF supported proliferation of GCTB stromal cells, and the addition of EGF and macrophage-colony stimulating factor promoted osteoclastogenesis.
In GCTB, EGFR signalling in neoplastic stromal cells may contribute to disease progression through promoting stromal cell proliferation and osteoclastogenesis.
Histopathology 09/2011; 59(3):376-89. · 3.08 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Collagen XVII/BP180, a hemidesmosomal adhesion protein, is lost during normal keratinocyte maturation; however, it may be reexpressed upon malignant transformation. In this work, highly sensitive monoclonal antibodies 6D1 and 9G2 were produced, characterized, and used for the detection of collagen XVII in a tissue microarray series of archived samples of nonmelanocytic epithelial neoplasias, including 5 verruca vulgaris, 14 seborrheic keratosis, 38 actinic keratosis, 38 basal cell carcinoma (BCC), 15 basosquamous carcinoma, 58 squamous cell carcinoma (SCC), and 9 normal skin. Digital microscopy and a new tissue microarray software linking image and patient data allowed easy and validated evaluation and quality archiving of stained samples. In normal skin and benign epidermal lesions, collagen XVII protein was restricted to basal keratinocytes. However, possibly as a sign of undifferentiated/transformed state, it was widely expressed in SCC showing elevated levels around invasive tumor fronts with some staining in tumor adjacent stroma, endothelium, and histiocytes. Collagen XVII immunostaining of atypical keratinocytes in most actinic/solar keratosis supports the view of their malignancy and common origin with SCC. Squamous component of basosquamous carcinoma showed moderate reaction, whereas islets of BCC were mainly negative reflecting the diverse genotype and phenotype, and pathogenesis of SCC and BCC. These results suggest that collagen XVII neoexpression may be associated with early atypia/malignant transformation of keratinocytes. Further investigations are under way to analyze the potential of these antibodies for tracing progression and metastatic potential of skin tumors.
Applied immunohistochemistry & molecular morphology: AIMM / official publication of the Society for Applied Immunohistochemistry 10/2008; 16(5):433-41. · 1.63 Impact Factor
-
Ferenc Pinter,
Judit Papay,
Andrea Almasi,
Zoltan Sapi,
Edit Szabo,
Melinda Kanya,
Anna Tamasi,
Balazs Jori,
Edit Varkondi,
Judit Moldvay,
Klara Szondy,
Gyorgy Keri,
Massimo Dominici,
Pierfranco Conte,
Sandor Eckhardt, Laszlo Kopper,
Richard Schwab,
Istvan Petak
[show abstract]
[hide abstract]
ABSTRACT: The purpose of this study was to investigate whether detectable protein biomarker overexpression is a prerequisite for the presence of increased gene copy number or activating mutations and responsiveness to the epidermal growth factor receptor (EGFR) inhibitors gefitinib and erlotinib in patients with lung adenocarcinomas. EGFR status was prospectively analyzed in tumor biopsy samples by three methods: protein expression (n = 117) by standardized immunohistochemistry (IHC), gene copy number (n = 97) by fluorescent in situ hybridization (FISH), and mutation analysis by sequencing (n = 126). Fifty-nine percent of the samples were positive by IHC, 40% were positive by FISH, and 13.5% contained activating kinase domain mutations. Thirty-four percent of the FISH-positive and 27% of the mutant samples were also IHC-negative. All EGFR mutant patients had major clinical responses (five complete response and five partial response) to gefitinib or erlotinib treatment, although three of these tumors were IHC-negative and four were FISH-negative. In a retrospective analysis of samples from nine patients with excellent therapeutic responses (three complete response, five partial response, one stable disease) to erlotinib or gefitinib, mutations were identified in eight cases, but IHC was negative in four of these tumors. These results indicate that molecular diagnostic methods appear to be most important for the identification of lung adenocarcinoma patients who may benefit from EGFR inhibitor treatments.
Journal of Molecular Diagnostics 04/2008; 10(2):160-8. · 3.58 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: This study, using tissue microarrays, aimed at the immunomorphologic profiling of nonsmall cell lung cancer (NSCLC) cases to reveal clinically relevant disease groups and biomarkers associated with patients' survival and tumor progression including brain metastatic potential. Donor tissue blocks were form 59 patients, including 33 primary tumors without distant metastasis and 26 brain metastatic primary tumors as well as the brain metastases. Sections were immunostained for 29 markers targeting molecules of cell adhesion, cell growth, cell cycle, and apoptosis regulation. beta-Catenin expression was the only independent prognostic marker associated with better outcome. Elevated expression of collagen XVII, CD44v6, and caspase-9, and the reduced production of beta-catenin and cellular apoptosis susceptibility protein were significantly associated with the metastatic potential of primary NSCLC. Expression of positive cell cycle regulators cyclin D1 and cyclin D3 was also increased in metastatic primary tumors. Metastatic tumor progression into the brain was accompanied by prominent p16, syndecan-1, p53 (DO7), and caspase-3 protein levels. Hierarchical clustering of complex immunoprofiles based on the differentially expressed markers grouped NSCLCs of the poorest outcome with high correlation including 2/3 of brain metastases of mixed histology. The brain metastatic potential of NSCLCs may be linked to the elevated levels of cyclinD1, cyclinD3, p16, p53, caspase-3, caspase-9, CD44v6, and collagen XVII and the down-regulation of beta-catenin and cellular apoptosis susceptibility protein. Unsupervised immunoprofiles based on differentially expressed biomarkers may help selecting lung cancers with aggressive behavior.
Applied immunohistochemistry & molecular morphology: AIMM / official publication of the Society for Applied Immunohistochemistry 04/2007; 15(1):19-30. · 1.63 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Suppression of cell death (most often apoptosis) by survival signals, or by defects in cell death signal transduction pathways, is considered one of the obligate hallmarks of malignant transformation. However, molecular survival strategies to evade cell death only have relevance in the presence of pro-death signals. Discovery of the apoptotic properties of oncogenes responsible for increased tumor cell proliferation (e.g. c-Myc) provided the most important example for such signals and led to the concept of synthetic lethal targeting as a strategy of identifying cancer specific drug target molecules. Besides growth signal autonomy, other hallmarks of oncogenesis (insensitivity to anti-growth signals, limitless replicative potential, invasion and metastasis, angiogenesis and increased genomic instability) are also challenged by increased susceptibility to various forms of cell death. Therefore, cancer cells must acquire survival strategies to suppress these cell death/apoptosis mechanisms. Novel signal transduction therapies can target molecules involved in these strategies to trigger tumor specific cell death.
Current Signal Transduction Therapy 12/2005; 1(1):113-131. · 0.50 Impact Factor
-
Richard Schwab,
Ferenc Pinter,
Judit Moldavy,
Judi Papay,
Janos Strausz, Laszlo Kopper,
Gyorgy Keri,
Akos Pap,
Istvan Petak,
Karoly Oreskovich,
Laszlo Mangel
Journal of Clinical Oncology 11/2005; 23(30):7736-8. · 18.37 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Granzyme M (GM) is a novel serine protease whose expression is highly restricted to natural killer (NK) cells, CD3(+)CD56(+) T cells, and gamma delta T cells. Using a GM-specific monoclonal antibody, we analyzed the expression of GM in 214 mature T-cell and NK-cell lymphomas. GM was preferentially expressed in nasal NK/T-cell lymphomas (100%), gamma delta T-cell lymphomas (100%), and intestinal T-cell lymphomas (85%). In contrast, GM expression was present at low prevalence in mycosis fungoides/Sézary syndrome (3%), anaplastic large-cell lymphoma (6%), panniculitis-like T-cell lymphoma (11%), and angioimmunoblastic T-cell lymphoma (0%) cases. Peripheral T-cell lymphomas of unspecified subtype showed an intermediate frequency (37%) of GM expression, consistent with their heterogeneous origin. We conclude that GM expression is a distinctive feature of the nasal NK/T-cell, gamma delta T-cell, and intestinal T-cell lymphomas, and suggest that these tumors develop from lymphocytes involved in innate immunity.
Blood 06/2003; 101(9):3590-3. · 9.90 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Anti-microtubule drugs and proteasome inhibitors are currently among the most intensively studied anti-tumor agents, however little is known about their pharmacological interactions at the cellular level.
The human promyelocytic leukemia cell line, HL-60, was exposed to nocodazole or etoposide in combination with proteasome or caspase inhibitors. Apoptotic cell death was detected by flow cytometry as sub-G1 population. Caspase and proteasome activities were monitored by the fluorogenic substrates Ac-DEVD-AMC and Suc-LLVY-AMC, respectively, in cell lysate. Heat shock protein 70 (HSP70) expression was determined by Western blotting.
Nocodazole, a microtubule inhibitor, induced caspase-dependent apoptosis in the HL-60 cell line. At sub-cytotoxic concentrations, proteasome inhibitors, including MG-132 or clasto-beta-lactone, decreased nocodazole-induced apoptotic DNA fragmentation without affecting the induction of caspase-3 activity. In contrast, MG-132 decreased both DNA fragmentation and caspase activation induced by etoposide, a topoisomerase-II inhibitor. HSP70 had previously been found to inhibit apoptosis independently from caspase activation. In this study, MG-132 up-regulated HSP70 protein expression, both in the presence or absence of nocodazole.
Proteasome inhibitors decreased anti-microtubule agent-induced apoptotic DNA fragmentation downstream of caspase-3 activation, possibly due to increased HSP70 expression. The results indicate that combination treatment with these novel anti-tumor agents in leukemia requires careful evaluation of their molecular interaction at the level of apoptosis induction.
Anticancer research 25(5):3321-6. · 1.73 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: It is a known paradox that many TGF beta 1-producing tumor cells are resistant to this, otherwise, inhibitory cytokine. In a lymphoma of B-cell origin exogenous TGF beta 1 was able to induce apoptosis, suggesting that the apoptosis program can be switched on. The apoptosis induction was independent of the death receptors but dependent on mitochondrial pathway and caspase-3. Probably due to the weak starting signal, caspase-3 further activated caspase-8 which, through the Bid cleavage and Bax translocation into the mitochondria, provided an autocatalytic support for the apoptotic program. There is a time-gat between the early activation of Smad-dependent TIEG and the accumulation of ROS, therefore other participants that start the increase in mitochondrial membrane permeability should be identified.
Anticancer research 22(6C):3867-72. · 1.73 Impact Factor
