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Dive into the research topics where Johannes Kornfehl is active.

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Featured researches published by Johannes Kornfehl.


Acta Oto-laryngologica | 2001

1,25(OH)2 vitamin D3 induces elevated expression of the cell cycle-regulating genes P21 and P27 in squamous carcinoma cell lines of the head and neck.

Gudrun Hager; Michael Formanek; Claudia Gedlicka; Dietmar Thurnher; Birgit Knerer; Johannes Kornfehl

The biologically active form of vitamin D3, 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], inhibits proliferation and induces differentiation for various malignant cells, including squamous cell carcinoma cell lines of the head and neck (SCCHN). These effects are due to an arrest of cells in the G0/G1 phase of the cell cycle and are predominantly mediated by the vitamin D receptor. To further explore the molecular mechanisms of the antiproliferative activity in SCCHN we studied the influence of 1,25(OH)2D3 on the expression of the G1 phase-regulating proteins cyclin D1, p21 and p27. Furthermore, as a direct target of G1 protein complexes, we investigated the phosphorylation status of the retinoblastoma protein (pRb). Synchronized cells of 2 SCCHN cell lines [JPPA (laryngeal carcinoma) and SCC 9 (tongue carcinoma)] and human immortalized keratinocytes (HaCaT) were cultured for 96 h in the presence or absence (ethanol as control) of 1,25(OH)2D3 (10(-7) M). At various time intervals the cell cycle status was detected by fluorescence-activated cell sorting (FACS) analysis and in parallel the expression of cell cycle-regulating proteins was determined at the protein and mRNA levels. In all cell lines tested 1,25(OH)2D3 caused an arrest of cells in the G0/G1 phase of the cell cycle and markedly induced the expression of the inhibitors p21 and p27. No influence was detectable on the expression of cyclin D1. Induction of p21 and p27 mRNA revealed transcriptional regulation by the vitamin D receptor. Simultaneously, hyperphosphorylated pRb was transformed to the hypophosphorylated form. Our results demonstrate that the biologically active form of vitamin D3 directly regulates the expression of p21 and p27, inducing a G0/G1 phase arrest: one mechanism by which 1,25(OH)2D3 controls cell proliferation inSCCHN.The biologically active form of vitamin D3, 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], inhibits proliferation and induces differentiation for various malignant cells, including squamous cell carcinoma cell lines of the head and neck (SCCHN). These effects are due to an arrest of cells in the G0/G1 phase of the cell cycle and are predominantly mediated by the vitamin D receptor. To further explore the molecular mechanisms of the antiproliferative activity in SCCHN we studied the influence of 1,25(OH)2D3 on the expression of the G1 phase-regulating proteins cyclin D1, p21 and p27. Furthermore, as a direct target of G1 protein complexes, we investigated the phosphorylation status of the retinoblastoma protein (pRb). Synchronized cells of 2 SCCHN cell lines [JPPA (laryngeal carcinoma) and SCC 9 (tongue carcinoma)] and human immortalized keratinocytes (HaCaT) were cultured for 96 h in the presence or absence (ethanol as control) of 1,25(OH)2D3 (10-7 M). At various time intervals the cell cycle status was detected by fluorescence-activated cell sorting (FACS) analysis and in parallel the expression of cell cycle-regulating proteins was determined at the protein and mRNA levels. In all cell lines tested 1,25(OH)2D3 caused an arrest of cells in the G0/G1 phase of the cell cycle and markedly induced the expression of the inhibitors p21 and p27. No influence was detectable on the expression of cyclin D1. Induction of p21 and p27 mRNA revealed transcriptional regulation by the vitamin D receptor. Simultaneously, hyperphosphorylated pRb was transformed to the hypophosphorylated form. Our results demonstrate that the biologically active form of vitamin D3 directly regulates the expression of p21 and p27, inducing a G0/G1 phase arrest: one mechanism by which 1,25(OH)2D3 controls cell proliferation in SCCHN.


Acta Oto-laryngologica | 2001

Non-steroidal anti-inflammatory drugs induce apoptosis in head and neck cancer cell lines.

Dietmar Thurnher; Maia Bakroeva; Gertraud Schütz; Martina Pelzmann; Michael Formanek; Birgit Knerer; Johannes Kornfehl

Non-steroidal anti-inflammatory drugs (NSAIDs) can inhibit tumorigenesis in colorectal cancer due to the induction of apoptosis. Disturbances of cellular pathways ultimately leading to apoptosis may contribute to the process of neoplastic transformation and immortalization. In this study we wanted to determine the influence of different NSAIDs (indomethacin, ibuprofen and sodium salicylate) and hydrocortisone on Bcl-2 expression and the apoptotic behavior of head and neck tumor cell lines and normal oral keratinocytes. Bcl-2 expression was determined by monoclonal antibody staining and fluorescence-activated cell-sorting measurement. Apoptotic cells were visualized with a epifluorescence microscope after staining with CytoDeath M30 antibody. Indomethacin (1 mM) and ibuprofen (1 mM) significantly reduced Bcl-2 expression in the cancer cell lines tested and might be thought responsible for the observed increase in apoptosis. At all concentrations tested the influence of sodium salicylate and hydrocortisone on Bcl-2 expression was not significant. In contrast, the NSAIDs tested had only a minor influence on normal oral keratinocytes. Our results demonstrate a significant reduction in growth and an increase in apoptosis, possibly due to a reduction in Bcl-2 expression. after exposure to indomethacin and ibuprofen in the head and neck cancer cell lines tested.Non-steroidal anti-inflammatory drugs (NSAIDs) can inhibit tumorigenesis in colorectal cancer due to the induction of apoptosis. Disturbances of cellular pathways ultimately leading to apoptosis may contribute to the process of neoplastic transformation and immortalization. In this study we wanted to determine the influence of different NSAIDs (indomethacin, ibuprofen and sodium salicylate) and hydrocortisone on Bcl-2 expression and the apoptotic behavior of head and neck tumor cell lines and normal oral keratinocytes. Bcl-2 expression was determined by monoclonal antibody staining and fluorescence-activated cell-sorting measurement. Apoptotic cells were visualized with a epifluorescence microscope after staining with CytoDeath M30 antibody. Indomethacin (1 mM) and ibuprofen (1 mM) significantly reduced Bcl-2 expression in the cancer cell lines tested and might be thought responsible for the observed increase in apoptosis. At all concentrations tested the influence of sodium salicylate and hydrocortisone on Bcl-2 expression was not significant. In contrast, the NSAIDs tested had only a minor influence on normal oral keratinocytes. Our results demonstrate a significant reduction in growth and an increase in apoptosis, possibly due to a reduction in Bcl-2 expression, after exposure to indomethacin and ibuprofen in the head and neck cancer cell lines tested.


Anti-Cancer Drugs | 2002

Mitoxantrone and cisplatin in recurrent and/or metastatic salivary gland malignancies.

Claudia Gedlicka; Birgit Schüll; Michael Formanek; Johannes Kornfehl; Martin Burian; Birgit Knerer; Edgar Selzer; Werner Scheithauer; Gabriela Kornek

A phase II study was performed to assess the safety and efficacy of mitoxantrone and cisplatin in locally recurrent and/or metastatic carcinomas of the salivary glands. Between May 1997 and March 2001, a total of 14 patients were entered on this trial. All of them had previously undergone radical resection and 10 were subsequently treated with adjuvant radiation therapy with (n =3) or without (n =7) concomitant chemotherapy. Therapy according to the study protocol consisted of mitoxantrone given as i.v. bolus on day 1 at a dose of 12 mg/m2 and cisplatin given as 90-min infusion at a dose of 30 mg/m2 on days 1–3. We observed two partial responses (14.3%) and stabilization of disease in nine patients (64.3%); progression during therapy was noted in only three cases (21.4%). The median time to progression was 15 months (range 2–36) and the median survival time was 27 months (range 4–54). Myelosuppression was commonly observed. Leukocytopenia occurred in all patients, and was grade 3 or 4 in three (21%) and four (29%) patients. WHO grade 3 thrombocytopenia and anemia was seen in three (21%) and four (29%) patients, respectively. Non-hematologic toxicity was in general mild to moderate except for two cases (14%) of grade 3 nausea and vomiting; overall incidence rates were nausea and vomiting (n =14), stomatitis (n =6), diarrhea (n =3), alopecia (n =11), infection (n =7), increase of serum creatinine (n =3), and peripheral neuropathy (n =3). The combination of mitoxantrone and cisplatin seems to be an active and fairly well-tolerated regimen for the treatment of advanced salivary gland cancers. According to the observed high rate of abrogating progressive disease for a long duration, and the resulting promising progression-free and overall survival time, further investigation seems warranted.


Acta Oto-laryngologica | 1998

Non-radioactive Semiquantitative Testing for Expression Levels of Telomerase Activity in Head and Neck Squamous Cell Carcinomas may be Indicative for Biological Tumour Behaviour

Dietmar Thurnher; Birgit Knerer; Michael Formanek; Johannes Kornfehl

Head and neck cancer arises and progresses through specific genetic alterations which lead to an invasive immortal phenotype. The process of immortalization is associated with the activation of the enzyme telomerase, a ribonucleoprotein with reverse transcriptase activity which is capable of synthesizing telomeric repeats at the end of chromosomes. This enzyme is expressed in nearly all neoplasms and germline cells and is absent in most normal human somatic cells. Because of this expression pattern testing for telomerase activity may deliver useful diagnostic and/or prognostic information about clinical tumour behaviour. Telomerase activity was therefore analysed in 16 primary lesions of head and neck squamous cell carcinomas (HNSCC) using the polymerase chain reaction-based telomeric repeat amplification protocol (TRAP). For a sensitive semiquantitative analysis of telomerase activity TRAP products were mixed with Pico Green I and the fluorescence emission intensities were measured. All 16 samples tested positive. When the Pico Green I data were compared with clinical parameters, it was obvious that N0 necks revealed significantly (p < 0.05) lower emission intensities (i.e. telomerase activity) than N + necks. Our results indicate that a high telomerase activity in HNSCC may facilitate lymph node metastasis and that the estimation of telomerase activity is a useful diagnostic tool which could influence treatment modalities.


Acta Oto-laryngologica | 1998

Different KGF Expression in Squamous Cell Carcinomas of the Head and Neck and in Normal Mucosa

Birgit Knerer; Michael Formanek; Bettina Schickinger; Helga Martinek; Johannes Kornfehl

Fibroblast growth factors (FGFs) are major factors mediating epithelial-mesenchymal interactions in the epidermis and mucosa. In this study the expression of the FGFs keratinocyte growth factor (KGF), acidic FGF (aFGF) and basic FGF (bFGF) was examined in tumour tissue specimens from 14 patients with advanced-stage squamous cell carcinoma of the head and neck (SCCHN) and 3 SCC cell lines by reverse-transcribed polymerase chain reaction (RT-PCR) and immunohistochemistry. None of the SCC cell lines was positive for KGF mRNA, whereas all cell lines were highly positive for aFGF and bFGF. In SCCHN tissue samples the level of KGF mRNA expression was significantly lower than in normal mucosa. Tumour stroma and the submucosal areas of normal mucosa stained intensely with anti-KGF antibody in immunohistochemical slides, whereas tumour cell nests were negative. Exposure of SCC cells to KGF thus differs from normal mucosa both quantitatively and regarding spatial distribution. This fact and the overexpression of aFGF and bFGF by tumour cells potentially promote tumour growth, invasion and metastasis. Since these growth factors and their receptors are well characterized, these observations could lead to new therapeutic strategies in SCCHN, for instance by blocking their receptors or antisense targeting.


Laryngo-rhino-otologie | 1993

Funktionelle und kanzerologische Aspekte bei der Verwendung von Jejunum im HNO-Bereich

M. Ch. Grasl; K. Ehrenberger; Johannes Kornfehl; H. Piza-Katzer; Rudolf Roka

Wir berichten uber die Erfahrung bei 76 Patienten, deren Defekte nach Resektion von ausgedehnten Tumoren im Kopf-Halsbereich mit frei transplantiertem, mikrovaskular anastomosiertem Jejunum zur funktionellen Rehabilitation rekonstruiert wurden.


Immunobiology | 1992

Autotransplanted Jejunum in Patients with Carcinomas of the Head and Neck: Transport of Immunosurveillance against Tumor Cells?

Johannes Kornfehl; Csilla Neuchrist; Matthäus Grasl; Hildegunde Piza; Rudolf Roka; K. Ehrenberger; Clemens Sorg; Dietrich Kraft; Otto Scheiner

Autologous jejunum, transplanted as a functional replacement immediately after radical dissection of advanced stages of squamous cell carcinomas of the head and neck and subsequently irradiated, was examined by immunohistochemistry (APAAP/PAP-technique). Biopsies from 9 patients were taken at the time of transplantation and up to 24 months thereafter (group 1) and from 5 patients only once after transplantation (group 2). Twenty-six monoclonal antibodies (mAbs) were used as surface markers to give an overview about phenotypical changes with respect to T-, B- and M phi-antigens. 1) B cells: a general increase of CR2+ (CD21, p less than 0.01) could be noticed after transplantation, immunoglobulin positive cells remained unchanged expect for a significant decrease of IgM+ (p less than 0.01) and IgA1+ (p less than 0.01) cells. 2) The number of T cells (CD3+) showed no significant differences although TcR gamma/delta+ cells decreased (p less than 0.01) in the autotransplant. ICAM-1 (CD54) and IL-2R (CD25) were found on a significant (p less than 0.01) higher number of cells after transplantation. 3) Cells with M/M phi morphology showed increased expression of the Fc gamma receptors (CD64, p less than 0.001; CD32, n.s.; CD16, p less than 0.001), of the complement receptors CR1 (CD35, (p less than 0.001) and CR3 (CD11b, p less than 0.02), of HLA-DQ (p less than 0.01), and of the antigens 25F9 (mature M phi; p less than 0.01) and CD4 (p less than 0.02). Correlation analyses of data obtained from the biopsies of the 14 autotransplanted jejunum cases revealed a CD35+ and a 25F9+ subpopulation of M/M phi. Our findings indicate that despite irradiation autotransplanted jejunum contained cells with immunological capacities. Therefore, the replacement of larynx by autologous jejunum may facilitate not only mechanical but also immunological functions.


Anti-Cancer Drugs | 2001

Ifosfamide and mitoxantrone in the treatment of recurrent and/or metastatic squamous cell carcinoma of the head and neck.

Dietmar Thurnher; Johannes Kornfehl; Martin Burian; Claudia Gedlicka; Edgar Selzer; Christian Quint; Csilla Neuchrist; Gabriela Kornek

A phase II study was performed to assess the safety and efficacy of ifosfamide and mitoxantrone in recurrent and/or metastatic squamous cell carcinomas of the head and neck. Treatment consisted of ifosfamide 1500 mg/m2 in 1000 ml saline, infused over 60 min and mesna 20% of the total dose of ifosfamide in three doses for 3 days combined with mitoxantrone 12 mg/m2 given as a short infusion on day 1. Treatment courses were repeated every 4 weeks until a total of six cycles. Twenty-two patients entered this trial, 13 of whom had received chemo- and radiation therapy, and nine patients who underwent radiation therapy with or without prior surgery. We observed no objective response, with the exception of two patients who experienced minor response (reduction of tumor size of 25%). The dose-limiting toxicity was myelosuppression with grade 3/4 leukocytopenia in seven patients (32%) and grade 3/4 neutropenia in 15 (68%). Severe organ toxicity except alopecia (91%) was not observed. Ifosfamide combined with mitoxantrone does not improve the therapeutic armentarium in recurrent squamous cell carcinoma of the head and neck.


Oto-rhino-laryngologia Nova | 1994

Kultivierung humaner oraler Keratinozyten

Johannes Kornfehl; Michael Formanek; Werner Millesi; Otto Scheiner

Die Deckung von Schleimhautdefekten des oberen aerodigestiven Traktes ist eines der Hauptprobleme sowohl der Tumor- als auch der prAprothetischen Chirurgie. Eine autologe in vitro kultivierte Sch


Journal of Oral Pathology & Medicine | 2007

Oral keratinocytes derived from the peritonsillar mucosa express the proinflammatory cytokine IL‐6 without prior stimulation

Michael Formanek; Birgit Knerer; Andreas F. P. Temmel; Dietmar Thurnher; Werner Millesi; Johannes Kornfehl

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Dietmar Thurnher

Medical University of Graz

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Claudia Gedlicka

Medical University of Vienna

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Edgar Selzer

Medical University of Vienna

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